1
|
Icer Baykal PB, Lara J, Khudyakov Y, Zelikovsky A, Skums P. Quantitative differences between intra-host HCV populations from persons with recently established and persistent infections. Virus Evol 2020; 7:veaa103. [PMID: 33505710 PMCID: PMC7816669 DOI: 10.1093/ve/veaa103] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Detection of incident hepatitis C virus (HCV) infections is crucial for identification of outbreaks and development of public health interventions. However, there is no single diagnostic assay for distinguishing recent and persistent HCV infections. HCV exists in each infected host as a heterogeneous population of genomic variants, whose evolutionary dynamics remain incompletely understood. Genetic analysis of such viral populations can be applied to the detection of incident HCV infections and used to understand intra-host viral evolution. We studied intra-host HCV populations sampled using next-generation sequencing from 98 recently and 256 persistently infected individuals. Genetic structure of the populations was evaluated using 245,878 viral sequences from these individuals and a set of selected features measuring their diversity, topological structure, complexity, strength of selection, epistasis, evolutionary dynamics, and physico-chemical properties. Distributions of the viral population features differ significantly between recent and persistent infections. A general increase in viral genetic diversity from recent to persistent infections is frequently accompanied by decline in genomic complexity and increase in structuredness of the HCV population, likely reflecting a high level of intra-host adaptation at later stages of infection. Using these findings, we developed a machine learning classifier for the infection staging, which yielded a detection accuracy of 95.22 per cent, thus providing a higher accuracy than other genomic-based models. The detection of a strong association between several HCV genetic factors and stages of infection suggests that intra-host HCV population develops in a complex but regular and predictable manner in the course of infection. The proposed models may serve as a foundation of cyber-molecular assays for staging infection, which could potentially complement and/or substitute standard laboratory assays.
Collapse
Affiliation(s)
- Pelin B Icer Baykal
- Department of Computer Science, Georgia State University, 25 Park Place, Atlanta, GA 30302, USA
| | - James Lara
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, 1600 Clifton Rd., Atlanta, GA 30329, USA
| | - Yury Khudyakov
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, 1600 Clifton Rd., Atlanta, GA 30329, USA
| | - Alex Zelikovsky
- Department of Computer Science, Georgia State University, 25 Park Place, Atlanta, GA 30302, USA
| | - Pavel Skums
- Department of Computer Science, Georgia State University, 25 Park Place, Atlanta, GA 30302, USA
| |
Collapse
|
2
|
Diversity of the hepatitis C virus NS5B gene during HIV co-infection. PLoS One 2020; 15:e0237162. [PMID: 32750098 PMCID: PMC7402467 DOI: 10.1371/journal.pone.0237162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 07/20/2020] [Indexed: 01/06/2023] Open
Abstract
Viral diversity is an important feature of hepatitis C virus (HCV) infection and an important predictor of disease progression and treatment response. HIV/HCV co-infection is associated with enhanced HCV replication, increased fibrosis, and the development of liver disease. HIV also increases quasispecies diversity of HCV structural genes, although limited data are available regarding the impact of HIV on non-structural genes of HCV, particularly in the absence of direct-acting therapies. The genetic diversity and presence of drug resistance mutations within the RNA-dependent RNA polymerase (NS5B) gene were examined in 3 groups of women with HCV genotype 1a infection, including those with HCV mono-infection, antiretroviral (ART)-naïve women with HIV/HCV co-infection and CD4 cell count <350 cells/mm3, and ART-naïve women with HIV/HCV co-infection and CD4 cell count ≥350 cells/mm3. None had ever been treated for HCV infection. There was evidence of significant diversity across the entire NS5B gene in all women. There were several nucleotides and amino acids with distinct distributions across the three study groups, although no obvious clustering of NS5B sequences was observed based on HIV co-infection or CD4 cell count. Polymorphisms at amino acid positions associated with resistance to dasabuvir and sofosbuvir were limited, although the Q309R variant associated with ribavirin resistance was present in 12 individuals with HCV mono-infection, 8 HIV/HCV co-infected individuals with CD4 <350 cells/mm3, and 12 HIV/HCV co-infected individuals with CD4 ≥350 cells/mm3. Previously reported fitness altering mutations were rare. CD8+ T cell responses against the human leukocyte antigen (HLA) B57-restricted epitopes NS5B2629-2637 and NS5B2936-2944 are critical for HCV control and were completely conserved in 44 (51.8%) and 70 (82.4%) study participants. These data demonstrate extensive variation across the NS5B gene. Genotypic variation may have a profound impact on HCV replication and pathogenesis and deserves careful evaluation.
Collapse
|
3
|
Robins WP, Mekalanos JJ. Protein covariance networks reveal interactions important to the emergence of SARS coronaviruses as human pathogens. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020. [PMID: 32577639 DOI: 10.1101/2020.06.05.136887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
SARS-CoV-2 is one of three recognized coronaviruses (CoVs) that have caused epidemics or pandemics in the 21 st century and that have likely emerged from animal reservoirs based on genomic similarities to bat and other animal viruses. Here we report the analysis of conserved interactions between amino acid residues in proteins encoded by SARS-CoV-related viruses. We identified pairs and networks of residue variants that exhibited statistically high frequencies of covariance with each other. While these interactions are likely key to both protein structure and other protein-protein interactions, we have also found that they can be used to provide a new computational approach (CoVariance-based Phylogeny Analysis) for understanding viral evolution and adaptation. Our data provide evidence that the evolutionary processes that converted a bat virus into human pathogen occurred through recombination with other viruses in combination with new adaptive mutations important for entry into human cells.
Collapse
|
4
|
Factors Influencing the Prevalence of Resistance-Associated Substitutions in NS5A Protein in Treatment-Naive Patients with Chronic Hepatitis C. Biomedicines 2020; 8:biomedicines8040080. [PMID: 32272736 PMCID: PMC7235841 DOI: 10.3390/biomedicines8040080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/24/2020] [Accepted: 04/05/2020] [Indexed: 12/12/2022] Open
Abstract
Direct-acting antivirals (DAAs) revolutionized treatment of hepatitis C virus (HCV) infection. Resistance-associated substitutions (RASs) present at the baseline impair response to DAA due to rapid selection of resistant HCV strains. NS5A is indispensable target of the current DAA treatment regimens. We evaluated prevalence of RASs in NS5A in DAA-naïve patients infected with HCV 1a (n = 19), 1b (n = 93), and 3a (n = 90) before systematic DAA application in the territory of the Russian Federation. Total proportion of strains carrying at least one RAS constituted 35.1% (71/202). In HCV 1a we detected only M28V (57.9%) attributed to a founder effect. Common RASs in HCV 1b were R30Q (7.5%), L31M (5.4%), P58S (4.4%), and Y93H (5.4%); in HCV 3a, A30S (31.0%), A30K (5.7%), S62L (8.9%), and Y93H (2.2%). Prevalence of RASs in NS5A of HCV 1b and 3a was similar to that worldwide, including countries practicing massive DAA application, i.e., it was not related to treatment. NS5A with and without RASs exhibited different co-variance networks, which could be attributed to the necessity to preserve viral fitness. Majority of RASs were localized in polymorphic regions subjected to immune pressure, with selected substitutions allowing immune escape. Altogether, this explains high prevalence of RAS in NS5A and low barrier for their appearance in DAA-inexperienced population.
Collapse
|
5
|
Statistical characteristics of amino acid covariance as possible descriptors of viral genomic complexity. Sci Rep 2019; 9:18410. [PMID: 31804522 PMCID: PMC6895170 DOI: 10.1038/s41598-019-54720-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 07/08/2019] [Indexed: 12/25/2022] Open
Abstract
At the sequence level it is hard to describe the complexity of viruses which allows them to challenge host immune system, some for a few weeks and others up to a complete compromise. Paradoxically, viral genomes are both complex and simple. Complex because amino acid mutation rates are very high, and yet viruses remain functional. Simple because they have barely around 10 types of proteins, so viral protein-protein interaction networks are not insightful. In this work we use fine-grained amino acid level information and their evolutionary characteristics obtained from large-scale genomic data to develop a statistical panel, towards the goal of developing quantitative descriptors for the biological complexity of viruses. Networks were constructed from pairwise covariation of amino acids and were statistically analyzed. Three differentiating factors arise: predominantly intra- vs inter-protein covariance relations, the nature of the node degree distribution and network density. Interestingly, the covariance relations were primarily intra-protein in avian influenza and inter-protein in HIV. The degree distributions showed two universality classes: a power-law with exponent −1 in HIV and avian-influenza, random behavior in human flu and dengue. The calculated covariance network density correlates well with the mortality strengths of viruses on the viral-Richter scale. These observations suggest the potential utility of the statistical metrics for describing the covariance patterns in viruses. Our host-virus interaction analysis point to the possibility that host proteins which can interact with multiple viral proteins may be responsible for shaping the inter-protein covariance relations. With the available data, it appears that network density might be a surrogate for the virus Richter scale, however the hypothesis needs a re-examination when large scale complete genome data for more viruses becomes available.
Collapse
|
6
|
Bayurova E, Jansons J, Skrastina D, Smirnova O, Mezale D, Kostyusheva A, Kostyushev D, Petkov S, Podschwadt P, Valuev-Elliston V, Sasinovich S, Korolev S, Warholm P, Latanova A, Starodubova E, Tukhvatulin A, Latyshev O, Selimov R, Metalnikov P, Komarov A, Ivanova O, Gorodnicheva T, Kochetkov S, Gottikh M, Strumfa I, Ivanov A, Gordeychuk I, Isaguliants M. HIV-1 Reverse Transcriptase Promotes Tumor Growth and Metastasis Formation via ROS-Dependent Upregulation of Twist. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:6016278. [PMID: 31885806 PMCID: PMC6915010 DOI: 10.1155/2019/6016278] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 11/01/2019] [Accepted: 11/05/2019] [Indexed: 12/15/2022]
Abstract
HIV-induced immune suppression results in the high prevalence of HIV/AIDS-associated malignancies including Kaposi sarcoma, non-Hodgkin lymphoma, and cervical cancer. HIV-infected people are also at an increased risk of "non-AIDS-defining" malignancies not directly linked to immune suppression but associated with viral infections. Their incidence is increasing despite successful antiretroviral therapy. The mechanism behind this phenomenon remains unclear. Here, we obtained daughter clones of murine mammary gland adenocarcinoma 4T1luc2 cells expressing consensus reverse transcriptase of HIV-1 subtype A FSU_A strain (RT_A) with and without primary mutations of drug resistance. In in vitro tests, mutations of resistance to nucleoside inhibitors K65R/M184V reduced the polymerase, and to nonnucleoside inhibitors K103N/G190S, the RNase H activities of RT_A. Expression of these RT_A variants in 4T1luc2 cells led to increased production of the reactive oxygen species (ROS), lipid peroxidation, enhanced cell motility in the wound healing assay, and upregulation of expression of Vimentin and Twist. These properties, particularly, the expression of Twist, correlated with the levels of expression RT_A and/or the production of ROS. When implanted into syngeneic BALB/C mice, 4T1luc2 cells expressing nonmutated RT_A demonstrated enhanced rate of tumor growth and increased metastatic activity, dependent on the level of expression of RT_A and Twist. No enhancement was observed for the clones expressing mutated RT_A variants. Plausible mechanisms are discussed involving differential interactions of mutated and nonmutated RTs with its cellular partners involved in the regulation of ROS. This study establishes links between the expression of HIV-1 RT, production of ROS, induction of EMT, and enhanced propagation of RT-expressing tumor cells. Such scenario can be proposed as one of the mechanisms of HIV-induced/enhanced carcinogenesis not associated with immune suppression.
Collapse
Affiliation(s)
- Ekaterina Bayurova
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
- Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, Moscow, Russia
| | - Juris Jansons
- Department of Pathology, Riga Stradins University, Riga, Latvia
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Dace Skrastina
- Department of Pathology, Riga Stradins University, Riga, Latvia
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Olga Smirnova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Dzeina Mezale
- Department of Pathology, Riga Stradins University, Riga, Latvia
| | - Anastasia Kostyusheva
- National Medical Research Center for Tuberculosis and Infectious Diseases, Moscow, Russia
| | - Dmitry Kostyushev
- National Medical Research Center for Tuberculosis and Infectious Diseases, Moscow, Russia
| | - Stefan Petkov
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Philip Podschwadt
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | | | - Sviataslau Sasinovich
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Sergey Korolev
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Per Warholm
- Science for Life Laboratory, Stockholm University, Stockholm, Sweden
| | - Anastasia Latanova
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Elizaveta Starodubova
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Amir Tukhvatulin
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
| | - Oleg Latyshev
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
| | - Renat Selimov
- Russian State Center for Quality and Standardization of Veterinary Drugs and Feed (VGNKI), Moscow, Russia
| | - Pavel Metalnikov
- Russian State Center for Quality and Standardization of Veterinary Drugs and Feed (VGNKI), Moscow, Russia
| | - Alexander Komarov
- Russian State Center for Quality and Standardization of Veterinary Drugs and Feed (VGNKI), Moscow, Russia
| | - Olga Ivanova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Sergey Kochetkov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Marina Gottikh
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Ilze Strumfa
- Department of Pathology, Riga Stradins University, Riga, Latvia
| | - Alexander Ivanov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Ilya Gordeychuk
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
- Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, Moscow, Russia
- Sechenov First Moscow State Medical University, Moscow, Russia
| | - Maria Isaguliants
- NF Gamaleya Research Center of Epidemiology and Microbiology, Moscow, Russia
- Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, Moscow, Russia
- Department of Pathology, Riga Stradins University, Riga, Latvia
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
7
|
Pathogenicity of the H1N1 influenza virus enhanced by functional synergy between the NPV100I and NAD248N pair. PLoS One 2019; 14:e0217691. [PMID: 31150476 PMCID: PMC6544299 DOI: 10.1371/journal.pone.0217691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 05/16/2019] [Indexed: 11/20/2022] Open
Abstract
By comparing and measuring covariations of viral protein sequences from isolates of the 2009 pH1N1 influenza A virus (IAV), specific substitutions that co-occur in the NP-NA pair were identified. To investigate the effect of these co-occurring substitution pairs, the V100I substitution in NP and the D248N substitution in NA were introduced into laboratory-adapted WSN IAVs. The recombinant WSN with the covarying NPV100I-NAD248N pair exhibited enhanced pathogenicity, as characterized by increased viral production, increased death and inflammation of host cells, and high mortality in infected mice. Although direct interactions between the NPV100I and NAD248N proteins were not detected, the RNA-binding ability of NPV100I was increased, which was further strengthened by NAD248N, in expression-plasmid-transfected cells. Additionally, the NAD248N protein was frequently recruited within lipid rafts, indirectly affecting the RNA-binding ability of NP as well as viral release. Altogether, our data indicate that the covarying NPV100I-NAD248N pair obtained from 2009 pH1N1 IAV sequence information function together to synergistically augment viral assembly and release, which may explain the observed enhanced viral pathogenicity.
Collapse
|
8
|
Abstract
Amino acid mutations in proteins are random and those mutations which are beneficial or neutral survive during the course of evolution. Conservation or co-evolution analyses are performed on the multiple sequence alignment of homologous proteins to understand how important different amino acids or groups of them are. However, these traditional analyses do not explore the directed influence of amino acid mutations, such as compensatory effects. In this work we develop a method to capture the directed evolutionary impact of one amino acid on all other amino acids, and provide a visual network representation for it. The method developed for these directed networks of inter- and intra-protein evolutionary interactions can also be used for noting the differences in amino acid evolution between the control and experimental groups. The analysis is illustrated with a few examples, where the method identifies several directed interactions of functionally critical amino acids. The impact of an amino acid is quantified as the number of amino acids that are influenced as a consequence of its mutation, and it is intended to summarize the compensatory mutations in large evolutionary sequence data sets as well as to rationally identify targets for mutagenesis when their functional significance can not be assessed using structure or conservation.
Collapse
|
9
|
Frequency of Interferon-Resistance Conferring Substitutions in Amino Acid Positions 70 and 91 of Core Protein of the Russian HCV 1b Isolates Analyzed in the T-Cell Epitopic Context. J Immunol Res 2018; 2018:7685371. [PMID: 29577052 PMCID: PMC5821972 DOI: 10.1155/2018/7685371] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/29/2017] [Indexed: 12/17/2022] Open
Abstract
Amino acid substitutions R70Q/H and L91M in HCV subtype 1b core protein can affect the response to interferon and are associated with the development of hepatocellular carcinoma. We found that the rate of R70Q/H in HCV 1b from Russia was 31.2%, similar to that in HCV strains from Asia (34.0%), higher than that in the European (18.0%, p = 0.0010), but lower than that in the US HCV 1b strains (62.8%, p < 0.0001). Substitution L91M was found in 80.4% of the Russian HCV 1b isolates, higher than in Asian isolates (43.8%, p < 0.0001). Thus, a significant proportion of Russian HCV 1b isolates carry the unfavorable R70Q/H and/or L91M substitution. In silico analysis of the epitopic structure of the regions of substitutions revealed that both harbor clusters of T-cell epitopes. Peptides encompassing these regions were predicted to bind to a panel of HLA class I molecules, with substitutions impairing peptide recognition by HLA I molecules of the alleles prevalent in Russia. This indicates that HCV 1b with R70Q/H and L91M substitutions may have evolved as the immune escape variants. Impairment of T-cell recognition may play a part in the negative effect of these substitutions on the response to IFN treatment.
Collapse
|
10
|
Li Z, Chen ZW, Li H, Ren H, Hu P. Prevalence of hepatitis C virus-resistant association substitutions to direct-acting antiviral agents in treatment-naïve hepatitis C genotype 1b-infected patients in western China. Infect Drug Resist 2017; 10:377-392. [PMID: 29184422 PMCID: PMC5673042 DOI: 10.2147/idr.s146595] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background Direct-acting antivirals (DAAs) against hepatitis C virus (HCV) are potent and highly efficacious. However, resistance-associated substitutions (RASs) relevant to DAAs can impair treatment effectiveness even at baseline. Moreover, the prevalence of baseline RASs in HCV genotype 1b-infected patients in western China is still unclear. Materials and methods Direct sequencing of the HCV NS3, NS5A, and NS5B regions was performed in baseline serum samples of 70 DAAs treatment-naïve HCV 1b-infected patients in western China. The sequences were analyzed with MEGA version 5.05 software. Evolutionary patterns of RASs and amino-acid covariance patterns in the NS3, NS5A, and NS5B genes were analyzed by MEGA and Cytoscape (version 3.2.1), respectively. Results The presence of at least one RAS in the NS3 region (C16S, T54S, Q80R/L, A87T, R117H, S122G, V132I, V170I) was observed in 85.48% (53 of 62) of patients, RASs in the NS5A region (L28M, R30Q, Q54H, P58S/T, Q62H/R, Y93H) were observed in 42.42% (28 of 66) of patients, and RASs in the NS5B region (N142S, A300T, C316N, A338V, S365A, L392I, M414L, I424V, A442T, V499A, S556G) were observed in 100% (44 of 44) of patients. Evolutionary patterns of RASs and amino-acid covariance patterns for the NS3, NS5A, and NS5B genes are reported. Conclusion The prevalence of RASs relevant to DAAs detected in the NS3, NS5A, and NS5B regions of HCV 1b from DAA treatment-naïve patients is high. Therefore, more attention should be paid to RASs associated with DAAs in the upcoming DAA-treatment era in China.
Collapse
Affiliation(s)
- Zhao Li
- Department of Infectious Diseases, Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, Chinese Ministry of Education, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhi-Wei Chen
- Department of Infectious Diseases, Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, Chinese Ministry of Education, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hu Li
- Department of Infectious Diseases, Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, Chinese Ministry of Education, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hong Ren
- Department of Infectious Diseases, Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, Chinese Ministry of Education, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Peng Hu
- Department of Infectious Diseases, Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, Chinese Ministry of Education, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
11
|
Murray JM, Maher S, Mota T, Suzuki K, Kelleher AD, Center RJ, Purcell D. Differentiating founder and chronic HIV envelope sequences. PLoS One 2017; 12:e0171572. [PMID: 28187204 PMCID: PMC5302377 DOI: 10.1371/journal.pone.0171572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 01/23/2017] [Indexed: 11/27/2022] Open
Abstract
Significant progress has been made in characterizing broadly neutralizing antibodies against the HIV envelope glycoprotein Env, but an effective vaccine has proven elusive. Vaccine development would be facilitated if common features of early founder virus required for transmission could be identified. Here we employ a combination of bioinformatic and operations research methods to determine the most prevalent features that distinguish 78 subtype B and 55 subtype C founder Env sequences from an equal number of chronic sequences. There were a number of equivalent optimal networks (based on the fewest covarying amino acid (AA) pairs or a measure of maximal covariance) that separated founders from chronics: 13 pairs for subtype B and 75 for subtype C. Every subtype B optimal solution contained the founder pairs 178–346 Asn-Val, 232–236 Thr-Ser, 240–340 Lys-Lys, 279–315 Asp-Lys, 291–792 Ala-Ile, 322–347 Asp-Thr, 535–620 Leu-Asp, 742–837 Arg-Phe, and 750–836 Asp-Ile; the most common optimal pairs for subtype C were 644–781 Lys-Ala (74 of 75 networks), 133–287 Ala-Gln (73/75) and 307–337 Ile-Gln (73/75). No pair was present in all optimal subtype C solutions highlighting the difficulty in targeting transmission with a single vaccine strain. Relative to the size of its domain (0.35% of Env), the α4β7 binding site occurred most frequently among optimal pairs, especially for subtype C: 4.2% of optimal pairs (1.2% for subtype B). Early sequences from 5 subtype B pre-seroconverters each exhibited at least one clone containing an optimal feature 553–624 (Ser-Asn), 724–747 (Arg-Arg), or 46–293 (Arg-Glu).
Collapse
Affiliation(s)
- John M. Murray
- School of Mathematics and Statistics, UNSW Sydney, Sydney, New South Wales, Australia
- * E-mail:
| | - Stephen Maher
- School of Mathematics and Statistics, UNSW Sydney, Sydney, New South Wales, Australia
- Zuse Institute Berlin, Berlin, Germany
| | - Talia Mota
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Kazuo Suzuki
- The Kirby Institute, UNSW Sydney, Sydney, New South Wales, Australia
| | | | - Rob J. Center
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Damian Purcell
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| |
Collapse
|
12
|
Counts CJ, Ho PS, Donlin MJ, Tavis JE, Chen C. A Functional Interplay between Human Immunodeficiency Virus Type 1 Protease Residues 77 and 93 Involved in Differential Regulation of Precursor Autoprocessing and Mature Protease Activity. PLoS One 2015; 10:e0123561. [PMID: 25893662 PMCID: PMC4404164 DOI: 10.1371/journal.pone.0123561] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 03/04/2015] [Indexed: 11/18/2022] Open
Abstract
HIV-1 protease (PR) is a viral enzyme vital to the production of infectious virions. It is initially synthesized as part of the Gag-Pol polyprotein precursor in the infected cell. The free mature PR is liberated as a result of precursor autoprocessing upon virion release. We previously described a model system to examine autoprocessing in transfected mammalian cells. Here, we report that a covariance analysis of miniprecursor (p6*-PR) sequences derived from drug naïve patients identified a series of amino acid pairs that vary together across independent viral isolates. These covariance pairs were used to build the first topology map of the miniprecursor that suggests high levels of interaction between the p6* peptide and the mature PR. Additionally, several PR-PR covariance pairs are located far from each other (>12 Å Cα to Cα) relative to their positions in the mature PR structure. Biochemical characterization of one such covariance pair (77-93) revealed that each residue shows distinct preference for one of three alkyl amino acids (V, I, and L) and that a polar or charged amino acid at either of these two positions abolishes precursor autoprocessing. The most commonly observed 77V is preferred by the most commonly observed 93I, but the 77I variant is preferred by other 93 variances (L, V, or M) in supporting precursor autoprocessing. Furthermore, the 77I93V covariant enhanced precursor autoprocessing and Gag polyprotein processing but decreased the mature PR activity. Therefore, both covariance and biochemical analyses support a functional association between residues 77 and 93, which are spatially distant from each other in the mature PR structure. Our data also suggests that these covariance pairs differentially regulate precursor autoprocessing and the mature protease activity.
Collapse
Affiliation(s)
- Christopher J. Counts
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - P. Shing Ho
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Maureen J. Donlin
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Saint Louis University Liver Center, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - John E. Tavis
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Saint Louis University Liver Center, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - Chaoping Chen
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, United States of America
| |
Collapse
|
13
|
HCV genome-wide genetic analyses in context of disease progression and hepatocellular carcinoma. PLoS One 2014; 9:e103748. [PMID: 25079603 PMCID: PMC4117537 DOI: 10.1371/journal.pone.0103748] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 07/01/2014] [Indexed: 12/20/2022] Open
Abstract
Hepatitis C virus (HCV) is a major cause of hepatitis and hepatocellular carcinoma (HCC) world-wide. Most HCV patients have relatively stable disease, but approximately 25% have progressive disease that often terminates in liver failure or HCC. HCV is highly variable genetically, with seven genotypes and multiple subtypes per genotype. This variation affects HCV's sensitivity to antiviral therapy and has been implicated to contribute to differences in disease. We sequenced the complete viral coding capacity for 107 HCV genotype 1 isolates to determine whether genetic variation between independent HCV isolates is associated with the rate of disease progression or development of HCC. Consensus sequences were determined by sequencing RT-PCR products from serum or plasma. Positions of amino acid conservation, amino acid diversity patterns, selection pressures, and genome-wide patterns of amino acid covariance were assessed in context of the clinical phenotypes. A few positions were found where the amino acid distributions or degree of positive selection differed between in the HCC and cirrhotic sequences. All other assessments of viral genetic variation and HCC failed to yield significant associations. Sequences from patients with slow disease progression were under a greater degree of positive selection than sequences from rapid progressors, but all other analyses comparing HCV from rapid and slow disease progressors were statistically insignificant. The failure to observe distinct sequence differences associated with disease progression or HCC employing methods that previously revealed strong associations with the outcome of interferon α-based therapy implies that variable ability of HCV to modulate interferon responses is not a dominant cause for differential pathology among HCV patients. This lack of significant associations also implies that host and/or environmental factors are the major causes of differential disease presentation in HCV patients.
Collapse
|
14
|
A bioinformatics pipeline for the analyses of viral escape dynamics and host immune responses during an infection. BIOMED RESEARCH INTERNATIONAL 2014; 2014:264519. [PMID: 25013771 PMCID: PMC4072169 DOI: 10.1155/2014/264519] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 05/08/2014] [Indexed: 01/21/2023]
Abstract
Rapidly mutating viruses, such as hepatitis C virus (HCV) and HIV, have adopted evolutionary strategies that allow escape from the host immune response via genomic mutations. Recent advances in high-throughput sequencing are reshaping the field of immuno-virology of viral infections, as these allow fast and cheap generation of genomic data. However, due to the large volumes of data generated, a thorough understanding of the biological and immunological significance of such information is often difficult. This paper proposes a pipeline that allows visualization and statistical analysis of viral mutations that are associated with immune escape. Taking next generation sequencing data from longitudinal analysis of HCV viral genomes during a single HCV infection, along with antigen specific T-cell responses detected from the same subject, we demonstrate the applicability of these tools in the context of primary HCV infection. We provide a statistical and visual explanation of the relationship between cooccurring mutations on the viral genome and the parallel adaptive immune response against HCV.
Collapse
|
15
|
Lara J, Purdy MA, Khudyakov YE. Genetic host specificity of hepatitis E virus. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2014; 24:127-39. [PMID: 24667049 PMCID: PMC5745802 DOI: 10.1016/j.meegid.2014.03.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 02/24/2014] [Accepted: 03/16/2014] [Indexed: 01/06/2023]
Abstract
Hepatitis E virus (HEV) causes epidemic and sporadic cases of hepatitis worldwide. HEV genotypes 3 (HEV3) and 4 (HEV4) infect humans and animals, with swine being the primary reservoir. The relevance of HEV genetic diversity to host adaptation is poorly understood. We employed a Bayesian network (BN) analysis of HEV3 and HEV4 to detect epistatic connectivity among protein sites and its association with the host specificity in each genotype. The data imply coevolution among ∼70% of polymorphic sites from all HEV proteins and association of numerous coevolving sites with adaptation to swine or humans. BN models for individual proteins and domains of the nonstructural polyprotein detected the host origin of HEV strains with accuracy of 74-93% and 63-87%, respectively. These findings, taken together with lack of phylogenetic association to host, suggest that the HEV host specificity is a heritable and convergent phenotypic trait achievable through variety of genetic pathways (abundance), and explain a broad host range for HEV3 and HEV4.
Collapse
Affiliation(s)
- James Lara
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Michael A Purdy
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Yury E Khudyakov
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, GA, USA
| |
Collapse
|
16
|
Statistical linkage analysis of substitutions in patient-derived sequences of genotype 1a hepatitis C virus nonstructural protein 3 exposes targets for immunogen design. J Virol 2014; 88:7628-44. [PMID: 24760894 DOI: 10.1128/jvi.03812-13] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
UNLABELLED Chronic hepatitis C virus (HCV) infection is one of the leading causes of liver failure and liver cancer, affecting around 3% of the world's population. The extreme sequence variability of the virus resulting from error-prone replication has thwarted the discovery of a universal prophylactic vaccine. It is known that vigorous and multispecific cellular immune responses, involving both helper CD4(+) and cytotoxic CD8(+) T cells, are associated with the spontaneous clearance of acute HCV infection. Escape mutations in viral epitopes can, however, abrogate protective T-cell responses, leading to viral persistence and associated pathologies. Despite the propensity of the virus to mutate, there might still exist substitutions that incur a fitness cost. In this paper, we identify groups of coevolving residues within HCV nonstructural protein 3 (NS3) by analyzing diverse sequences of this protein using ideas from random matrix theory and associated methods. Our analyses indicate that one of these groups comprises a large percentage of residues for which HCV appears to resist multiple simultaneous substitutions. Targeting multiple residues in this group through vaccine-induced immune responses should either lead to viral recognition or elicit escape substitutions that compromise viral fitness. Our predictions are supported by published clinical data, which suggested that immune genotypes associated with spontaneous clearance of HCV preferentially recognized and targeted this vulnerable group of residues. Moreover, mapping the sites of this group onto the available protein structure provided insight into its functional significance. An epitope-based immunogen is proposed as an alternative to the NS3 epitopes in the peptide-based vaccine IC41. IMPORTANCE Despite much experimental work on HCV, a thorough statistical study of the HCV sequences for the purpose of immunogen design was missing in the literature. Such a study is vital to identify epistatic couplings among residues that can provide useful insights for designing a potent vaccine. In this work, ideas from random matrix theory were applied to characterize the statistics of substitutions within the diverse publicly available sequences of the genotype 1a HCV NS3 protein, leading to a group of sites for which HCV appears to resist simultaneous substitutions possibly due to deleterious effect on viral fitness. Our analysis leads to completely novel immunogen designs for HCV. In addition, the NS3 epitopes used in the recently proposed peptide-based vaccine IC41 were analyzed in the context of our framework. Our analysis predicts that alternative NS3 epitopes may be worth exploring as they might be more efficacious.
Collapse
|
17
|
Murray JM, Moenne-Loccoz R, Velay A, Habersetzer F, Doffoël M, Gut JP, Fofana I, Zeisel MB, Stoll-Keller F, Baumert TF, Schvoerer E. Genotype 1 hepatitis C virus envelope features that determine antiviral response assessed through optimal covariance networks. PLoS One 2013; 8:e67254. [PMID: 23840641 PMCID: PMC3688619 DOI: 10.1371/journal.pone.0067254] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Accepted: 05/14/2013] [Indexed: 01/25/2023] Open
Abstract
The poor response to the combined antiviral therapy of pegylated alfa-interferon and ribavarin for hepatitis C virus (HCV) infection may be linked to mutations in the viral envelope gene E1E2 (env), which can result in escape from the immune response and higher efficacy of viral entry. Mutations that result in failure of therapy most likely require compensatory mutations to achieve sufficient change in envelope structure and function. Compensatory mutations were investigated by determining positions in the E1E2 gene where amino acids (aa) covaried across groups of individuals. We assessed networks of covarying positions in E1E2 sequences that differentiated sustained virological response (SVR) from non-response (NR) in 43 genotype 1a (17 SVR), and 49 genotype 1b (25 SVR) chronically HCV-infected individuals. Binary integer programming over covariance networks was used to extract aa combinations that differed between response groups. Genotype 1a E1E2 sequences exhibited higher degrees of covariance and clustered into 3 main groups while 1b sequences exhibited no clustering. Between 5 and 9 aa pairs were required to separate SVR from NR in each genotype. aa in hypervariable region 1 were 6 times more likely than chance to occur in the optimal networks. The pair 531-626 (EI) appeared frequently in the optimal networks and was present in 6 of 9 NR in one of the 1a clusters. The most frequent pairs representing SVR were 431-481 (EE), 500-522 (QA) in 1a, and 407-434 (AQ) in 1b. Optimal networks based on covarying aa pairs in HCV envelope can indicate features that are associated with failure or success to antiviral therapy.
Collapse
Affiliation(s)
- John M Murray
- School of Mathematics and Statistics, University of New South Wales, Sydney, NSW, Australia.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Jeulin H, Velay A, Murray J, Schvoerer E. Clinical impact of hepatitis B and C virus envelope glycoproteins. World J Gastroenterol 2013; 19:654-664. [PMID: 23429668 PMCID: PMC3574591 DOI: 10.3748/wjg.v19.i5.654] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 12/17/2012] [Indexed: 02/06/2023] Open
Abstract
Chronic infection by either hepatitis B virus (HBV) or hepatitis C virus (HCV) share epidemiological characteristics with risks for development of severe complications such as liver cirrhosis and hepatocellular carcinoma. HBV and HCV also share a high genetic variability. Among highly variable regions, viral genes encoding surface proteins (hepatitis B surface antigen, E1/E2 HCV glycoproteins) play key roles in the stimulation of the host-related immune response and viral entry into hepatocytes. Specific segments of HBV envelope proteins (preS1, “a” determinant) are crucial in the entry process into permissive cells. HCV entry is a complex multistep process involving multiple cell cofactors (glycosaminoglycans, low density lipoprotein receptor, SR-B1, CD81, claudin-1, occludin, EGFR, EphA2) in the interaction with HCV E1/E2 envelope glycoproteins. In vitro both viruses can be controlled by antibody-mediated neutralization targeting viral envelope, also essential in preventing HBV infection in vivo as observed through successful vaccination using HBs antigen. But preventive vaccination and/or therapeutic pressure can influence HBV and HCV variability. For HBV, the patterns of antiviral drug resistance in chronic hepatitis are complex and the original pol/S gene overlap has to be taken into account. Treatment-induced HBV mutations in pol could indeed generate S mutants with subsequent modified antigenicity or increased cancer induction. Variability of HBV and HCV envelope proteins combining high exposure to selective pressures and crucial functional roles require investigation in the context of diagnostic, vaccination and treatment tools. In this editorial a synthesis is performed of HBV and HCV envelope properties at the entry step and as antigenic proteins, and the subsequent clinical impact.
Collapse
MESH Headings
- Animals
- Antiviral Agents/therapeutic use
- Drug Resistance, Viral
- Genotype
- Hepacivirus/drug effects
- Hepacivirus/genetics
- Hepacivirus/immunology
- Hepacivirus/metabolism
- Hepacivirus/pathogenicity
- Hepatitis B Vaccines
- Hepatitis B virus/drug effects
- Hepatitis B virus/genetics
- Hepatitis B virus/immunology
- Hepatitis B virus/metabolism
- Hepatitis B virus/pathogenicity
- Hepatitis B, Chronic/diagnosis
- Hepatitis B, Chronic/drug therapy
- Hepatitis B, Chronic/immunology
- Hepatitis B, Chronic/prevention & control
- Hepatitis B, Chronic/virology
- Hepatitis C, Chronic/diagnosis
- Hepatitis C, Chronic/drug therapy
- Hepatitis C, Chronic/immunology
- Hepatitis C, Chronic/prevention & control
- Hepatitis C, Chronic/virology
- Host-Pathogen Interactions
- Humans
- Phenotype
- Prognosis
- Viral Envelope Proteins/genetics
- Viral Envelope Proteins/metabolism
Collapse
|
19
|
Abozaid SM, Shoukri M, Al-Qahtani A, Al-Ahdal MN. Prevailing genotypes of hepatitis C virus in Saudi Arabia: a systematic analysis of evidence. Ann Saudi Med 2013; 33:1-5. [PMID: 23458931 PMCID: PMC6078584 DOI: 10.5144/0256-4947.2013.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND AND OBJECTIVES Although hepatitis C virus (HCV) genotype 4 has been reported to be prevalent in some countries of the Middle East, the genotype distribution in some geographical areas is not conclusive. We aimed to perform a meta-analysis on available literature on this issue in an attempt to identify or confirm the prevailing HCV genotypes in Saudi Arabia. METHODS We searched for reports describing genotypes in Saudi Arabia. A meta-analysis was performed on the samples in 18 studies, published between 1995 and 2011, in which HCV genotypes were identified. RESULTS A total of 2277 specimens from 18 studies showed that 617, 82, 119 and 1198 subjects were HCV-positive for genotypes 1, 2, 3 and 4, respectively. The meta-analyses showed that there is a great deal of heterogeneity in estimated prevalence among the studies. The highest prevalence was found in genotype HCV-4, followed by HCV-1, HCV-3, and HCV-2. CONCLUSION Our meta-analysei emphasizes that HCV genotype 4 is the most prevalent, followed by genotype 1. Further studies on genotype determination and subtype distribution are warranted.
Collapse
Affiliation(s)
- Suhair M Abozaid
- Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | | | | | | |
Collapse
|
20
|
Lara J, Khudyakov Y. Epistatic connectivity among HCV genomic sites as a genetic marker of interferon resistance. Antivir Ther 2012; 17:1471-5. [PMID: 23321567 PMCID: PMC5762110 DOI: 10.3851/imp2478] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2012] [Indexed: 12/24/2022]
Abstract
Until recently, the standard-of-care therapy of patients with HCV infection involves treatment with interferon (IFN) and ribavirin (RBV). Host demographic and genetic factors as well as HCV genetic heterogeneity have been shown to be associated with outcomes of therapy. Although resistance to IFN/RBV remains an important clinical and public health problem, there are no reliable genetic markers for the prediction of the therapy outcomes. Recently, it was shown that adaptation to IFN, a major constituent of the host innate immunity, is reflected in the HCV genetic composition and epistatic connectivity among polymorphic genomic sites, thus providing novel genetic markers of IFN resistance. Consideration of coordinated evolution among HCV genomic sites allows for identification of these genetic markers from short regions of the HCV genome and for accurate prediction of therapeutic outcomes. HCV genomic co-evolution offers a general framework for the detection of predisposition to IFN resistance, and possibly to resistance to direct-acting antivirals.
Collapse
Affiliation(s)
- James Lara
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | | |
Collapse
|
21
|
Li X, Zhang Z, Song J. Computational enzyme design approaches with significant biological outcomes: progress and challenges. Comput Struct Biotechnol J 2012; 2:e201209007. [PMID: 24688648 PMCID: PMC3962085 DOI: 10.5936/csbj.201209007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/27/2012] [Accepted: 10/04/2012] [Indexed: 11/29/2022] Open
Abstract
Enzymes are powerful biocatalysts, however, so far there is still a large gap between the number of enzyme-based practical applications and that of naturally occurring enzymes. Multiple experimental approaches have been applied to generate nearly all possible mutations of target enzymes, allowing the identification of desirable variants with improved properties to meet the practical needs. Meanwhile, an increasing number of computational methods have been developed to assist in the modification of enzymes during the past few decades. With the development of bioinformatic algorithms, computational approaches are now able to provide more precise guidance for enzyme engineering and make it more efficient and less laborious. In this review, we summarize the recent advances of method development with significant biological outcomes to provide important insights into successful computational protein designs. We also discuss the limitations and challenges of existing methods and the future directions that should improve them.
Collapse
Affiliation(s)
- Xiaoman Li
- National Engineering Laboratory for Industrial Enzymes and Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, Tianjin 300308, China
| | - Ziding Zhang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Jiangning Song
- National Engineering Laboratory for Industrial Enzymes and Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, Tianjin 300308, China ; Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Melbourne, VIC 3800, Australia
| |
Collapse
|
22
|
Molenaar-de Backer MWA, Lukashov VV, van Binnendijk RS, Boot HJ, Zaaijer HL. Global co-existence of two evolutionary lineages of parvovirus B19 1a, different in genome-wide synonymous positions. PLoS One 2012; 7:e43206. [PMID: 22912828 PMCID: PMC3418230 DOI: 10.1371/journal.pone.0043206] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 07/18/2012] [Indexed: 11/18/2022] Open
Abstract
Parvovirus B19 (B19V) can cause infection in humans. To date, three genotypes of B19V, with subtypes, are known, of which genotype 1a is the most prevalent genotype in the Western world. We sequenced the genome of B19V strains of 65 asymptomatic, recently infected Dutch blood donors, to investigate the spatio-temporal distribution of B19V strains, in the years 2003-2009. The sequences were compared to B19V sequences from Dutch patients with fifth disease, and to global B19V sequences as available from GenBank. All Dutch B19V strains belonged to genotype 1a. Phylogenetic analysis of the strains from Dutch blood donors showed that two groups of genotype 1a co-exist. A clear-cut division into the two groups was also found among the B19V strains from Dutch patients, and among the B19V sequences in GenBank. The two groups of genotype 1a co-exist around the world and do not appear to differ in their ability to cause disease. Strikingly, the two groups of B19V predominantly differ in synonymous mutations, distributed throughout the entire genome of B19V. We propose to call the two groups of B19V genotype 1a respectively subtype 1a1 and 1a2.
Collapse
|
23
|
Abstract
Coordinated variation among positions in amino acid sequence alignments can reveal genetic dependencies at noncontiguous positions, but methods to assess these interactions are incompletely developed. Previously, we found genome-wide networks of covarying residue positions in the hepatitis C virus genome (R. Aurora, M. J. Donlin, N. A. Cannon, and J. E. Tavis, J. Clin. Invest. 119:225-236, 2009). Here, we asked whether such networks are present in a diverse set of viruses and, if so, what they may imply about viral biology. Viral sequences were obtained for 16 viruses in 13 species from 9 families. The entire viral coding potential for each virus was aligned, all possible amino acid covariances were identified using the observed-minus-expected-squared algorithm at a false-discovery rate of ≤1%, and networks of covariances were assessed using standard methods. Covariances that spanned the viral coding potential were common in all viruses. In all cases, the covariances formed a single network that contained essentially all of the covariances. The hepatitis C virus networks had hub-and-spoke topologies, but all other networks had random topologies with an unusually large number of highly connected nodes. These results indicate that genome-wide networks of genetic associations and the coordinated evolution they imply are very common in viral genomes, that the networks rarely have the hub-and-spoke topology that dominates other biological networks, and that network topologies can vary substantially even within a given viral group. Five examples with hepatitis B virus and poliovirus are presented to illustrate how covariance network analysis can lead to inferences about viral biology.
Collapse
|
24
|
Novel nucleotide and amino acid covariation between the 5'UTR and the NS2/NS3 proteins of hepatitis C virus: bioinformatic and functional analyses. PLoS One 2011; 6:e25530. [PMID: 21980483 PMCID: PMC3182228 DOI: 10.1371/journal.pone.0025530] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 09/06/2011] [Indexed: 01/02/2023] Open
Abstract
Molecular covariation of highly polymorphic viruses is thought to have crucial effects on viral replication and fitness. This study employs association rule data mining of hepatitis C virus (HCV) sequences to search for specific evolutionary covariation and then tests functional relevance on HCV replication. Data mining is performed between nucleotides in the untranslated regions 5′ and 3′UTR, and the amino acid residues in the non-structural proteins NS2, NS3 and NS5B. Results indicate covariance of the 243rd nucleotide of the 5′UTR with the 14th, 41st, 76th, 110th, 211th and 212th residues of NS2 and with the 71st, 175th and 621st residues of NS3. Real-time experiments using an HCV subgenomic system to quantify viral replication confirm replication regulation for each covariant pair between 5′UTR243 and NS2-41, -76, -110, -211, and NS3-71, -175. The HCV subgenomic system with/without the NS2 region shows that regulatory effects vanish without NS2, so replicative modulation mediated by HCV 5′UTR243 depends on NS2. Strong binding of the NS2 variants to HCV RNA correlates with reduced HCV replication whereas weak binding correlates with restoration of HCV replication efficiency, as determined by RNA-protein immunoprecipitation assay band intensity. The dominant haplotype 5′UTR243-NS2-41-76-110-211-NS3-71-175 differs according to the HCV genotype: G-Ile-Ile-Ile-Gly-Ile-Met for genotype 1b and A-Leu-Val-Leu-Ser-Val-Leu for genotypes 1a, 2a and 2b. In conclusion, 5′UTR243 co-varies with specific NS2/3 protein amino acid residues, which may have significant structural and functional consequences for HCV replication. This unreported mechanism involving HCV replication possibly can be exploited in the development of advanced anti-HCV medication.
Collapse
|
25
|
Ramachandran S, Zhai X, Thai H, Campo DS, Xia G, Ganova-Raeva LM, Drobeniuc J, Khudyakov YE. Evaluation of intra-host variants of the entire hepatitis B virus genome. PLoS One 2011; 6:e25232. [PMID: 21949887 PMCID: PMC3176825 DOI: 10.1371/journal.pone.0025232] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 08/30/2011] [Indexed: 02/07/2023] Open
Abstract
Genetic analysis of hepatitis B virus (HBV) frequently involves study of intra-host variants, identification of which is commonly achieved using short regions of the HBV genome. However, the use of short sequences significantly limits evaluation of genetic relatedness among HBV strains. Although analysis of HBV complete genomes using genetic cloning has been developed, its application is highly labor intensive and practiced only infrequently. We describe here a novel approach to whole genome (WG) HBV quasispecies analysis based on end-point, limiting-dilution real-time PCR (EPLD-PCR) for amplification of single HBV genome variants, and their subsequent sequencing. EPLD-PCR was used to analyze WG quasispecies from serum samples of patients (n = 38) infected with HBV genotypes A, B, C, D, E and G. Phylogenetic analysis of the EPLD-isolated HBV-WG quasispecies showed the presence of mixed genotypes, recombinant variants and sub-populations of the virus. A critical observation was that HBV-WG consensus sequences obtained by direct sequencing of PCR fragments without EPLD are genetically close, but not always identical to the major HBV variants in the intra-host population, thus indicating that consensus sequences should be judiciously used in genetic analysis. Sequence-based studies of HBV WG quasispecies should afford a more accurate assessment of HBV evolution in various clinical and epidemiological settings.
Collapse
Affiliation(s)
- Sumathi Ramachandran
- Molecular Epidemiology and Bioinformatics Laboratory, Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Fonseca-Coronado S, Vaughan G, Cruz-Rivera MY, Carpio-Pedroza JC, Ruiz-Tovar K, Ruiz-Pacheco JA, Escobar-Gutiérrez A. Interleukin-28B genotyping by melt-mismatch amplification mutation assay PCR analysis using single nucleotide polymorphisms rs12979860 and rs8099917, a useful tool for prediction of therapy response in hepatitis C patients. J Clin Microbiol 2011; 49:2706-2710. [PMID: 21613433 PMCID: PMC3147879 DOI: 10.1128/jcm.00877-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 05/12/2011] [Indexed: 02/07/2023] Open
Abstract
Several studies have identified associations between single nucleotide polymorphisms (SNPs) occurring near the interleukin-28B (IL-28B) gene and response to antiviral treatment among hepatitis C virus (HCV) patients. Here, we describe a reliable melt-mismatch amplification mutation assay (melt-MAMA) PCR-based genotyping method for IL-28B which can be used in the management of HCV patients, helping to better define the course of therapy.
Collapse
Affiliation(s)
- Salvador Fonseca-Coronado
- Unidad de Investigación Multidisciplinaria, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Gilberto Vaughan
- Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
| | - Mayra Yolanda Cruz-Rivera
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Juan Carlos Carpio-Pedroza
- Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
| | - Karina Ruiz-Tovar
- Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
| | - Juan Alberto Ruiz-Pacheco
- Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
| | - Alejandro Escobar-Gutiérrez
- Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
| |
Collapse
|
27
|
Cao F, Donlin MJ, Turner K, Cheng X, Tavis JE. Genetic and biochemical diversity in the HCV NS5B RNA polymerase in the context of interferon α plus ribavirin therapy. J Viral Hepat 2011; 18:349-57. [PMID: 20529202 PMCID: PMC3039702 DOI: 10.1111/j.1365-2893.2010.01316.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The hepatitis C virus (HCV) RNA polymerase (RdRp) may be a target of the drug ribavirin, and it is an object of drug development. Independent isolates of any HCV subtype differ genetically by approximately 10%, but the effects of this variation on enzymatic activity and drug sensitivity are poorly understood. We proposed that nucleotide use profiles (G/U ratio) among subtype 1b RdRps may reflect their use of ribavirin. Here, we characterized how subtype 1b genetic variation affects RNA polymerase activity and evaluated the G/U ratio as a surrogate for ribavirin use during pegylated interferon α and ribavirin therapy. Genetic and biochemical variation in the RdRp was compared between responders who would be largely sensitive to ribavirin and relapsers who would be mostly resistant. There were no consistent genetic differences between responder and relapser RdRps. RNA polymerization, RNA binding and primer usage varied widely among the RdRps, but these parameters did not differ significantly between the response groups. The G/U ratio among a set of subtype 1a RdRps increased rather than decreased following failed therapy, as would be expected if it reflected ribavirin use. Finally, RdRp activity was significantly associated with ALT levels. These data indicate that (i) current genetic approaches cannot predict RNA polymerase behaviour, (ii) the G/U ratio is not a surrogate for ribavirin use, (iii) RdRp activity may contribute to liver disease by modulating viral mRNA and antigen levels, and (iv) drug candidates should be tested against multiple patient-derived enzymes to ensure widespread efficacy even within a viral subtype.
Collapse
Affiliation(s)
- Feng Cao
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
| | - Maureen J. Donlin
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
- Saint Louis University Liver Center, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
| | - Kanika Turner
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
| | - Xiaohong Cheng
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
| | - John E. Tavis
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
- Saint Louis University Liver Center, Saint Louis University School of Medicine, 1100 S. Grand Blvd., Saint Louis, MO 63104 USA
| |
Collapse
|
28
|
Lara J, Xia G, Purdy M, Khudyakov Y. Coevolution of the hepatitis C virus polyprotein sites in patients on combined pegylated interferon and ribavirin therapy. J Virol 2011; 85:3649-63. [PMID: 21248044 PMCID: PMC3067842 DOI: 10.1128/jvi.02197-10] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 01/07/2011] [Indexed: 12/19/2022] Open
Abstract
Genotype-specific sensitivity of the hepatitis C virus (HCV) to interferon-ribavirin (IFN-RBV) combination therapy and reduced HCV response to IFN-RBV as infection progresses from acute to chronic infection suggest that HCV genetic factors and intrahost HCV evolution play important roles in therapy outcomes. HCV polyprotein sequences (n = 40) from 10 patients with unsustainable response (UR) (breakthrough and relapse) and 10 patients with no response (NR) following therapy were identified through the Virahep-C study. Bayesian networks (BNs) were constructed to relate interrelationships among HCV polymorphic sites to UR/NR outcomes. All models showed an extensive interdependence of HCV sites and strong connections (P ≤ 0.003) to therapy response. Although all HCV proteins contributed to the networks, the topological properties of sites differed among proteins. E2 and NS5A together contributed ∼40% of all sites and ∼62% of all links to the polyprotein BN. The NS5A BN and E2 BN predicted UR/NR outcomes with 85% and 97.5% accuracy, respectively, in 10-fold cross-validation experiments. The NS5A model constructed using physicochemical properties of only five sites was shown to predict the UR/NR outcomes with 83.3% accuracy for 6 UR and 12 NR cases of the HALT-C study. Thus, HCV adaptation to IFN-RBV is a complex trait encoded in the interrelationships among many sites along the entire HCV polyprotein. E2 and NS5A generate broad epistatic connectivity across the HCV polyprotein and essentially shape intrahost HCV evolution toward the IFN-RBV resistance. Both proteins can be used to accurately predict the outcomes of IFN-RBV therapy.
Collapse
Affiliation(s)
- James Lara
- Molecular Epidemiology & Bioinformatics Laboratory, Laboratory Branch, Division of Viral Hepatitis, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, Georgia 30333
| | - Guoliang Xia
- Molecular Epidemiology & Bioinformatics Laboratory, Laboratory Branch, Division of Viral Hepatitis, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, Georgia 30333
| | - Mike Purdy
- Molecular Epidemiology & Bioinformatics Laboratory, Laboratory Branch, Division of Viral Hepatitis, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, Georgia 30333
| | - Yury Khudyakov
- Molecular Epidemiology & Bioinformatics Laboratory, Laboratory Branch, Division of Viral Hepatitis, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, Georgia 30333
| |
Collapse
|
29
|
Tavis JE, Donlin MJ, Aurora R, Fan X, Di Bisceglie AM. Prospects for personalizing antiviral therapy for hepatitis C virus with pharmacogenetics. Genome Med 2011; 3:8. [PMID: 21345258 PMCID: PMC3092093 DOI: 10.1186/gm222] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Chronic hepatitis C virus (HCV) infection is a major cause of liver disease worldwide. HCV infection is currently treated with IFNα plus ribavirin for 24 to 48 weeks. This demanding therapy fails in up to 50% of patients, so the use of pharmacogenetic biomarkers to predict the outcome of treatment would reduce futile treatment of non-responders and help identify patients in whom therapy would be justified. Both IFNα and ribavirin primarily act by modulating the immune system of the patient, and HCV uses multiple mechanisms to counteract the antiviral effects stimulated by therapy. Therefore, response to therapy is influenced by variations in human genes governing the immune system and by differences in HCV genes that blunt antiviral immune responses. This article summarizes recent advances in understanding how host and viral genetic variation affect outcome of therapy. The most notable human associations are polymorphisms within the IL28B gene, but variations in human leukocyte antigen and cytokine genes have also been associated with treatment outcome. The most prominent viral genetic association with outcome of therapy is that HCV genotype 1 is much less sensitive to treatment than genotypes 2 and 3, but genetic differences below the genotype level also influence outcome of therapy, presumably by modulating the ability of viral genes to blunt antiviral immune responses. Pharmacogenetic prediction of the outcome of IFN-based therapy for HCV will require integrating the efficacies of the immunosuppressive mechanisms of a viral isolate, and then interpreting the viral resistance potential in context of the genetic profile of the patient at loci associated with outcome of therapy. Direct-acting inhibitors of HCV that will be used in combination with IFNα are nearing approval, so genetic prediction for anti-HCV therapy will soon need to incorporate viral genetic markers of viral resistance to the new drugs.
Collapse
Affiliation(s)
- John E Tavis
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA.
| | | | | | | | | |
Collapse
|
30
|
Margeridon-Thermet S, Shafer RW. Comparison of the Mechanisms of Drug Resistance among HIV, Hepatitis B, and Hepatitis C. Viruses 2010; 2:2696-739. [PMID: 21243082 PMCID: PMC3020796 DOI: 10.3390/v2122696] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2010] [Revised: 11/15/2010] [Accepted: 12/07/2010] [Indexed: 02/07/2023] Open
Abstract
Human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) are the most prevalent deadly chronic viral diseases. HIV is treated by small molecule inhibitors. HBV is treated by immunomodulation and small molecule inhibitors. HCV is currently treated primarily by immunomodulation but many small molecules are in clinical development. Although HIV is a retrovirus, HBV is a double-stranded DNA virus, and HCV is a single-stranded RNA virus, antiviral drug resistance complicates the development of drugs and the successful treatment of each of these viruses. Although their replication cycles, therapeutic targets, and evolutionary mechanisms are different, the fundamental approaches to identifying and characterizing HIV, HBV, and HCV drug resistance are similar. This review describes the evolution of HIV, HBV, and HCV within individuals and populations and the genetic mechanisms associated with drug resistance to each of the antiviral drug classes used for their treatment.
Collapse
Affiliation(s)
| | - Robert W. Shafer
- Departments of Medicine and Pathology, Stanford University, Stanford, CA 94305, USA; E-Mails: (S.M.T.)
| |
Collapse
|
31
|
Baseline prediction of combination therapy outcome in hepatitis C virus 1b infected patients by discriminant analysis using viral and host factors. PLoS One 2010; 5:e14132. [PMID: 21152430 PMCID: PMC2994723 DOI: 10.1371/journal.pone.0014132] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 11/08/2010] [Indexed: 12/12/2022] Open
Abstract
Background Current treatment of chronic hepatitis C virus (HCV) infection has limited efficacy −especially among genotype 1 infected patients−, is costly, and involves severe side effects. Thus, predicting non-response is of major interest for both patient wellbeing and health care expense. At present, treatment cannot be individualized on the basis of any baseline predictor of response. We aimed to identify pre-treatment clinical and virological parameters associated with treatment failure, as well as to assess whether therapy outcome could be predicted at baseline. Methodology Forty-three HCV subtype 1b (HCV-1b) chronically infected patients treated with pegylated-interferon alpha plus ribavirin were retrospectively studied (21 responders and 22 non-responders). Host (gender, age, weight, transaminase levels, fibrosis stage, and source of infection) and viral-related factors (viral load, and genetic variability in the E1–E2 and Core regions) were assessed. Logistic regression and discriminant analyses were used to develop predictive models. A “leave-one-out” cross-validation method was used to assess the reliability of the discriminant models. Principal Findings Lower alanine transaminase levels (ALT, p = 0.009), a higher number of quasispecies variants in the E1–E2 region (number of haplotypes, nHap_E1–E2) (p = 0.003), and the absence of both amino acid arginine at position 70 and leucine at position 91 in the Core region (p = 0.039) were significantly associated with treatment failure. Therapy outcome was most accurately predicted by discriminant analysis (90.5% sensitivity and 95.5% specificity, 85.7% sensitivity and 81.8% specificity after cross-validation); the most significant variables included in the predictive model were the Core amino acid pattern, the nHap_E1–E2, and gamma-glutamyl transferase and ALT levels. Conclusions and Significance Discriminant analysis has been shown as a useful tool to predict treatment outcome using baseline HCV genetic variability and host characteristics. The discriminant models obtained in this study led to accurate predictions in our population of Spanish HCV-1b treatment naïve patients.
Collapse
|
32
|
TenCate V, Sainz B, Cotler SJ, Uprichard SL. Potential treatment options and future research to increase hepatitis C virus treatment response rate. Hepat Med 2010; 2010:125-145. [PMID: 21331152 PMCID: PMC3039485 DOI: 10.2147/hmer.s7193] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C virus (HCV) is a liver-tropic blood-borne pathogen that affects more than 170 million people worldwide. Although acute infections are usually asymptomatic, up to 90% of HCV infections persist with the possibility of long-term consequences such as liver fibrosis, cirrhosis, steatosis, insulin resistance, or hepatocellular carcinoma. As such, HCV-associated liver disease is a major public health concern. Although the currently available standard of care therapy of pegylated interferon α plus ribavirin successfully treats infection in a subset of patients, the development of more effective, less toxic HCV antivirals is a health care imperative. This review not only discusses the limitations of the current HCV standard of care but also evaluates upcoming HCV treatment options and how current research elucidating the viral life cycle is facilitating the development of HCV-specific therapeutics that promise to greatly improve treatment response rates both before and after liver transplantation.
Collapse
Affiliation(s)
- Veronica TenCate
- Department of Medicine, Section of Hepatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Bruno Sainz
- Department of Medicine, Section of Hepatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Scott J Cotler
- Department of Medicine, Section of Hepatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Susan L Uprichard
- Department of Medicine, Section of Hepatology, University of Illinois at Chicago, Chicago, IL, USA
| |
Collapse
|
33
|
Asselah T, Estrabaud E, Bieche I, Lapalus M, De Muynck S, Vidaud M, Saadoun D, Soumelis V, Marcellin P. Hepatitis C: viral and host factors associated with non-response to pegylated interferon plus ribavirin. Liver Int 2010; 30:1259-69. [PMID: 20633102 PMCID: PMC3071938 DOI: 10.1111/j.1478-3231.2010.02283.x] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Treatment for chronic hepatitis C virus (HCV) infection has evolved considerably in the last years. The standard of care (SOC) for HCV infection consists in the combination of pegylated interferon (PEG-IFN) plus ribavirin. However, it only induces a sustained virological response (SVR) in half of genotype 1-infected patients. Several viral and host factors have been associated with non-response: steatosis, obesity, insulin resistance, age, male sex, ethnicity and genotypes. Many studies have demonstrated that in non-responders, some interferon-stimulated genes were upregulated before treatment. Those findings associated to clinical, biochemical and histological data may help detect responders before starting any treatment. This is a very important issue because the standard treatment is physically and economically demanding. The future of HCV treatment would probably consist in the addition of specifically targeted antiviral therapy for HCV such as protease and/or polymerase inhibitors to the SOC. In genotype 1 patients, very promising results have been reported when the protease inhibitor telaprevir or boceprevir is added to the SOC. It increases the SVR rates from approximately 50% (PEG-IFN plus ribavirin) to 70% (for patients treated with a combination of PEG-IFN plus ribavirin plus telaprevir). Different elements are associated with non-response: (i) viral factors, (ii) host factors and (iii) molecular mechanisms induced by HCV proteins to inhibit the IFN signalling pathway. The goal of this review is to present the mechanisms of non-response, to overcome it and to identify factors that can help to predict the response to anti-HCV therapy.
Collapse
Affiliation(s)
- Tarik Asselah
- INSERM, U773, Centre de Recherche Bichat-Beaujon CRB3, Paris, France.
| | - Emilie Estrabaud
- INSERMU773, Centre de Recherche Bichat-Beaujon CRB3, Paris, France
| | - Ivan Bieche
- INSERMU745, Université René Descartes, Paris, France,Service de Biochimie, Hôpital BeaujonClichy, France
| | - Martine Lapalus
- INSERMU773, Centre de Recherche Bichat-Beaujon CRB3, Paris, France
| | - Simon De Muynck
- INSERMU773, Centre de Recherche Bichat-Beaujon CRB3, Paris, France
| | - Michel Vidaud
- INSERMU745, Université René Descartes, Paris, France,Service de Biochimie, Hôpital BeaujonClichy, France
| | - David Saadoun
- Service de Médecine Interne, Hôpital Pitié-SalpétrièreParis, France
| | | | - Patrick Marcellin
- INSERMU773, Centre de Recherche Bichat-Beaujon CRB3, Paris, France,Service d'hépatologie, Hôpital BeaujonClichy, France
| |
Collapse
|
34
|
Fafi-Kremer S, Fofana I, Soulier E, Carolla P, Meuleman P, Leroux-Roels G, Patel AH, Cosset FL, Pessaux P, Doffoël M, Wolf P, Stoll-Keller F, Baumert TF. Viral entry and escape from antibody-mediated neutralization influence hepatitis C virus reinfection in liver transplantation. J Exp Med 2010; 207:2019-31. [PMID: 20713596 PMCID: PMC2931157 DOI: 10.1084/jem.20090766] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Accepted: 07/08/2010] [Indexed: 12/12/2022] Open
Abstract
End-stage liver disease caused by chronic hepatitis C virus (HCV) infection is a leading cause for liver transplantation (LT). Due to viral evasion from host immune responses and the absence of preventive antiviral strategies, reinfection of the graft is universal. The mechanisms by which the virus evades host immunity to reinfect the liver graft are unknown. In a longitudinal analysis of six HCV-infected patients undergoing LT, we demonstrate that HCV variants reinfecting the liver graft were characterized by efficient entry and poor neutralization by antibodies present in pretransplant serum compared with variants not detected after transplantation. Monoclonal antibodies directed against HCV envelope glycoproteins or a cellular entry factor efficiently cross-neutralized infection of human hepatocytes by patient-derived viral isolates that were resistant to autologous host-neutralizing responses. These findings provide significant insights into the molecular mechanisms of viral evasion during HCV reinfection and suggest that viral entry is a viable target for prevention of HCV reinfection of the liver graft.
Collapse
Affiliation(s)
- Samira Fafi-Kremer
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
- Laboratoire de Virologie, Pôle des Pathologies Digestives, Hépatiques et Transplantation, and Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France
| | - Isabel Fofana
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
| | - Eric Soulier
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
| | - Patric Carolla
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
| | - Philip Meuleman
- Center for Vaccinology, Ghent University and Hospital, 9000 Ghent, Belgium
| | - Geert Leroux-Roels
- Center for Vaccinology, Ghent University and Hospital, 9000 Ghent, Belgium
| | - Arvind H. Patel
- Medical Research Council Centre for Virus Research, University of Glasgow, Glasgow G11 5JR, Scotland, UK
| | - François-Loïc Cosset
- Institut National de la Santé et de la Recherche Médicale, Unité 758, Institut Fédératif de Recherche 128, Ecole Normale Supérieure, Université Claude Bernard Lyon 1, Université de Lyon, F-69007 Lyon, France
| | - Patrick Pessaux
- Université de Strasbourg, F-67000 Strasbourg, France
- Laboratoire de Virologie, Pôle des Pathologies Digestives, Hépatiques et Transplantation, and Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France
| | - Michel Doffoël
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
- Laboratoire de Virologie, Pôle des Pathologies Digestives, Hépatiques et Transplantation, and Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France
| | - Philippe Wolf
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
- Laboratoire de Virologie, Pôle des Pathologies Digestives, Hépatiques et Transplantation, and Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France
| | - Françoise Stoll-Keller
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
- Laboratoire de Virologie, Pôle des Pathologies Digestives, Hépatiques et Transplantation, and Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France
| | - Thomas F. Baumert
- Institut National de la Santé et de la Recherche Médicale, Unité 748, F-67000 Strasbourg, France
- Université de Strasbourg, F-67000 Strasbourg, France
- Laboratoire de Virologie, Pôle des Pathologies Digestives, Hépatiques et Transplantation, and Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France
| |
Collapse
|
35
|
Donlin MJ, Cannon NA, Aurora R, Li J, Wahed AS, Di Bisceglie AM, Tavis JE, for the Virahep-C Study Group. Contribution of genome-wide HCV genetic differences to outcome of interferon-based therapy in Caucasian American and African American patients. PLoS One 2010; 5:e9032. [PMID: 20140258 PMCID: PMC2815788 DOI: 10.1371/journal.pone.0009032] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 01/11/2010] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Hepatitis C virus (HCV) has six major genotypes, and patients infected with genotype 1 respond less well to interferon-based therapy than other genotypes. African American patients respond to interferon alpha-based therapy at about half the rate of Caucasian Americans. The effect of HCV's genetic variation on treatment outcome in both racial groups is poorly understood. METHODOLOGY We determined the near full-length pre-therapy consensus sequences from 94 patients infected with HCV genotype 1a or 1b undergoing treatment with peginterferon alpha-2a and ribavirin through the Virahep-C study. The sequences were stratified by genotype, race and treatment outcome to identify HCV genetic differences associated with treatment efficacy. PRINCIPAL FINDINGS HCV sequences from patients who achieved sustained viral response were more diverse than sequences from non-responders. These inter-patient diversity differences were found primarily in the NS5A gene in genotype 1a and in core and NS2 in genotype 1b. These differences could not be explained by host selection pressures. Genotype 1b but not 1a African American patients had viral genetic differences that correlated with treatment outcome. CONCLUSIONS & SIGNIFICANCE Higher inter-patient viral genetic diversity correlated with successful treatment, implying that there are HCV genotype 1 strains with intrinsic differences in sensitivity to therapy. Core, NS3 and NS5A have interferon-suppressive activities detectable through in vitro assays, and hence these activities also appear to function in human patients. Both preferential infection with relatively resistant HCV variants and host-specific factors appear to contribute to the unusually poor response to therapy in African American patients.
Collapse
Affiliation(s)
- Maureen J. Donlin
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Saint Louis University Liver Center, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - Nathan A. Cannon
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - Rajeev Aurora
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - Jia Li
- Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Abdus S. Wahed
- Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Adrian M. Di Bisceglie
- Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Saint Louis University Liver Center, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - John E. Tavis
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Saint Louis University Liver Center, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
| | | |
Collapse
|
36
|
Suppiah V, Moldovan M, Ahlenstiel G, Berg T, Weltman M, Abate ML, Bassendine M, Spengler U, Dore GJ, Powell E, Riordan S, Sheridan D, Smedile A, Fragomeli V, Müller T, Bahlo M, Stewart GJ, Booth DR, George J. IL28B is associated with response to chronic hepatitis C interferon-alpha and ribavirin therapy. Nat Genet 2009; 41:1100-4. [PMID: 19749758 DOI: 10.1038/ng.447] [Citation(s) in RCA: 1500] [Impact Index Per Article: 93.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Accepted: 08/14/2009] [Indexed: 12/11/2022]
Abstract
Hepatitis C virus (HCV) infects 3% of the world's population. Treatment of chronic HCV consists of a combination of PEGylated interferon-alpha (PEG-IFN-alpha) and ribavirin (RBV). To identify genetic variants associated with HCV treatment response, we conducted a genome-wide association study of sustained virological response (SVR) to PEG-IFN-alpha/RBV combination therapy in 293 Australian individuals with genotype 1 chronic hepatitis C, with validation in an independent replication cohort consisting of 555 individuals. We report an association to SVR within the gene region encoding interleukin 28B (IL28B, also called IFNlambda3; rs8099917 combined P = 9.25 x 10(-9), OR = 1.98, 95% CI = 1.57-2.52). IL28B contributes to viral resistance and is known to be upregulated by interferons and by RNA virus infection. These data suggest that host genetics may be useful for the prediction of drug response, and they also support the investigation of the role of IL28B in the treatment of HCV and in other diseases treated with IFN-alpha.
Collapse
|
37
|
Hepatitis C: recent successes and continuing challenges in the development of improved treatment modalities. Curr Opin Pharmacol 2009; 9:537-44. [PMID: 19762279 DOI: 10.1016/j.coph.2009.08.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Accepted: 08/21/2009] [Indexed: 01/11/2023]
Abstract
Dramatic progress is being made toward the development of less-toxic and simpler alternatives to the current standard-of-care therapy for chronic hepatitis C, which involves a combination of pegylated interferon (peg-IFN) and ribavirin (RBV). Several accessible viral targets have been identified and licensure of the most advanced clinical compounds can be anticipated within the next several years. However, the highly replicative nature of HCV infection, coupled with error-prone viral RNA synthesis and considerable genome diversity, pose extraordinary challenges to drug development. Peg-IFN is likely to remain a mainstay of therapy for the foreseeable future, or until such time that multiple direct-acting antiviral (STAT-C) inhibitors are available and shown to provide a sufficiently high barrier to resistance when used in combination.
Collapse
|
38
|
Pang PS, Planet PJ, Glenn JS. The evolution of the major hepatitis C genotypes correlates with clinical response to interferon therapy. PLoS One 2009; 4:e6579. [PMID: 19668364 PMCID: PMC2719056 DOI: 10.1371/journal.pone.0006579] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Accepted: 07/09/2009] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Patients chronically infected with hepatitis C virus (HCV) require significantly different durations of therapy and achieve substantially different sustained virologic response rates to interferon-based therapies, depending on the HCV genotype with which they are infected. There currently exists no systematic framework that explains these genotype-specific response rates. Since humans are the only known natural hosts for HCV-a virus that is at least hundreds of years old-one possibility is that over the time frame of this relationship, HCV accumulated adaptive mutations that confer increasing resistance to the human immune system. Given that interferon therapy functions by triggering an immune response, we hypothesized that clinical response rates are a reflection of viral evolutionary adaptations to the immune system. METHODS AND FINDINGS We have performed the first phylogenetic analysis to include all available full-length HCV genomic sequences (n = 345). This resulted in a new cladogram of HCV. This tree establishes for the first time the relative evolutionary ages of the major HCV genotypes. The outcome data from prospective clinical trials that studied interferon and ribavirin therapy was then mapped onto this new tree. This mapping revealed a correlation between genotype-specific responses to therapy and respective genotype age. This correlation allows us to predict that genotypes 5 and 6, for which there currently are no published prospective trials, will likely have intermediate response rates, similar to genotype 3. Ancestral protein sequence reconstruction was also performed, which identified the HCV proteins E2 and NS5A as potential determinants of genotype-specific clinical outcome. Biochemical studies have independently identified these same two proteins as having genotype-specific abilities to inhibit the innate immune factor double-stranded RNA-dependent protein kinase (PKR). CONCLUSION An evolutionary analysis of all available HCV genomes supports the hypothesis that immune selection was a significant driving force in the divergence of the major HCV genotypes and that viral factors that acquired the ability to inhibit the immune response may play a role in determining genotype-specific response rates to interferon therapy.
Collapse
Affiliation(s)
- Phillip S. Pang
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine and Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Palo Alto, California, United States of America
| | - Paul J. Planet
- Department of Pediatrics, Division of Infectious Diseases, Columbia Presbyterian Medical Center and, Sackler Institute of Comparative Genomics, American Museum of Natural History, New York, New York, United States of America
| | - Jeffrey S. Glenn
- Department of Medicine, Division of Gastroenterology and Hepatology, Stanford University School of Medicine and the Palo Alto Veterans Administration Medical Center, Palo Alto, California, United States of America
| |
Collapse
|
39
|
Selmi C, Podda M, Gershwin ME. Old and rising stars in the lymphoid liver. Semin Immunopathol 2009; 31:279-82. [PMID: 19603169 PMCID: PMC2758171 DOI: 10.1007/s00281-009-0175-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Accepted: 06/12/2009] [Indexed: 12/11/2022]
Affiliation(s)
- Carlo Selmi
- Department of Internal Medicine, IRCCS Istituto Clinico Humanitas, University of Milan, Milan, Italy
| | | | | |
Collapse
|
40
|
Abstract
Current treatment for chronic hepatitis C is expensive, is often accompanied by burdensome side effects, and, sadly, fails in almost half of cases. The ability to predict such failures prior to treatment could save a great deal of pain and expense for the patient with HCV. In this issue of the JCI, Aurora and colleagues describe the development of genetic markers predictive of treatment response based on a study of viral sequence variation (see the related article beginning on page 225). Genome-wide covariation analyses of pretreatment virus sequences from 94 patients showed distinct patterns of mutations strongly associated with the ultimate success or failure of treatment. Such analyses suggest markers predictive of response to therapy and may lead to new insights into the underlying biology of hepatitis C.
Collapse
Affiliation(s)
- Thomas S Oh
- Center for the Study of Hepatitis C, The Rockefeller University, New York, NY 10065, USA
| | | |
Collapse
|
41
|
Shapshak P, Somboonwit C, Drumright LN, Frost SDW, Commins D, Tellinghuisen TL, Scott WK, Duncan R, McCoy C, Page JB, Giunta B, Fernandez F, Singer E, Levine A, Minagar A, Oluwadara O, Kotila T, Chiappelli F, Sinnott JT. Molecular and contextual markers of hepatitis C virus and drug abuse. Mol Diagn Ther 2009; 13:153-79. [PMID: 19650670 PMCID: PMC4447498 DOI: 10.2165/01250444-200913030-00002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The spread of hepatitis C virus (HCV) infection involves a complex interplay of social risks, and molecular factors of both virus and host. Injection drug abuse is the most powerful risk factor for HCV infection, followed by sexual transmission and additional non-injection drug abuse factors such as co-infection with other viruses and barriers to treatment. It is clearly important to understand the wider context in which the factors related to HCV infection occur. This understanding is required for a comprehensive approach leading to the successful prevention, diagnosis, and treatment of HCV. An additional consideration is that current treatments and advanced molecular methods are generally unavailable to socially disadvantaged patients. Thus, the recognition of behavioral/social, viral, and host factors as components of an integrated approach to HCV is important to help this vulnerable group. Equally important, this approach is key to the development of personalized patient treatment - a significant goal in global healthcare. In this review, we discuss recent findings concerning the impact of drug abuse, epidemiology, social behavior, virology, immunopathology, and genetics on HCV infection and the course of disease.
Collapse
Affiliation(s)
- Paul Shapshak
- Division of Infectious Disease and International Medicine, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|