Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Methodol. Dec 26, 2015; 5(4): 230-237
Published online Dec 26, 2015. doi: 10.5662/wjm.v5.i4.230
Recombinant outer membrane protein F-B subunit of LT protein as a prophylactic measure against Pseudomonas aeruginosa burn infection in mice
Hassan Heydari Farsani, Iraj Rasooli, Seyed Latif Mousavi Gargari, Shahram Nazarian, Shakiba Darwish Alipour Astaneh
Hassan Heydari Farsani, Iraj Rasooli, Seyed Latif Mousavi Gargari, Department of Biology, Shahed University, Tehran-Qom Express Way, Opposite Imam Khomeini’s Shrine, Tehran 3319118651, Iran
Shakiba Darwish Alipour Astaneh, Faculty of Biotechnology, University of Semnan, Semnan 3513119111, Iran
Iraj Rasooli, Molecular Microbiology Research Center, Shahed University, Tehran 1417953836, Iran
Shahram Nazarian, Department of Biology, Faculty Of Science, Imam Hussein University, Tehran 1489684511, Iran
Author contributions: Rasooli I contributed to the conception and design of the study, or acquisition of data, or analysis and interpretation of data; Farsani HH carried out the experimental part of the project; Astaneh SDA supervised the experiments; Nazarian S drafted the article; Gargari SLM revised it critically for important intellectual content; final approval of the version to be submitted was made by Rasooli I.
Institutional review board statement: This work was carried out as a part of M.Sc thesis of Mr. Hassan Heydari Farsani at Shahed University. The thesis proposal was approved by postgraduate committee in Biology department of the aforementioned University.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of the Shahed University (IACUC protocol number: 917584001).
Conflict-of-interest statement: The authors declare no conflict of interests.
Data sharing statement: Technical details and dataset available from the corresponding author at rasooli@shahed.ac.ir. No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Iraj Rasooli, Professor, Department of Biology, Shahed University, Tehran-Qom Express Way, Opposite Imam Khomeini’s Shrine, Tehran 3319118651, Iran. rasooli@shahed.ac.ir
Telephone: +98-21-51212200 Fax: +98-21-51212201
Received: May 9, 2015
Peer-review started: May 11, 2015
First decision: July 6, 2015
Revised: November 10, 2015
Accepted: December 1, 2015
Article in press: December 2, 2015
Published online: December 26, 2015
Abstract

AIM: To study immunogenicity of outer membrane protein F (OprF) fused with B subunit of LT (LTB), against Pseudomonas aeruginosa (P. aeruginosa).

METHODS: The OprF, a major surface exposed outer membrane protein that is antigenically conserved in various strains of P. aeruginosa, is a promising immunogen against P. aeruginosa. In the present study recombinant OprF and OprF-LTB fusion gene was cloned, expressed and purified. BALB/c mice and rabbits were immunized using recombinant OprF and OprF-LTB and challenged at the burn site with P. aeruginosa lethal dose of 104 CFU. The protective efficacy of rabbit anti OprF IgG against P. aeruginosa burn infection was investigated by passive immunization.

RESULTS: It has been well established that the LTB is a powerful immunomodulator with strong adjuvant activity. LTB as a bacterial adjuvant enhanced immunogenicity of OprF and anti OprF IgG titer in serum was increased. Experimental findings showed significantly higher average survival rate in burned mice immunized with OprF-LTB than immunized with OprF or the control group. Rabbits anti OprF IgG brought about 75% survival of mice following challenge with P. aeruginosa. Post challenge hepatic and splenic tissues of mice group immunized with OprF-LTB had significantly lower bacterial load than those immunized with OprF or the control groups.

CONCLUSION: These results demonstrate that LTB-fused OprF might be a potential candidate protein for a prophylactic measure against P. aeruginosa in burn infection.

Keywords: Pseudomonas aeruginosa, Outer membrane protein F, B subunit of LT, Immunization, Burn

Core tip:Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen that infects hospitalized, burned and immunosuppressed patients. Vaccination of high-risk groups may reduce the incidence and spread of infection. In this study outer membrane protein F (OprF) and fusion genes containing OprF and B subunit of LT were cloned and expressed. The proteins were administered to the experimental mice challenged at the burn site with lethal dose of P. aeruginosa. Significant protection was noted in immunized animals.