Gene therapy for liver regeneration: Experimental studies and prospects for clinical trials

Table 1 General characteristics of most commonly used vectors

System	Size of insert (kb)	Infect non-dividing cell	Genomic integration	Duration of expression	Immune response
Adenovirus
1st generation	5	Yes	No	3-4 wk	High
2nd generation	8	Yes	No	Longer with Immuno-supression	High
Gutless	35	Yes	No		Less
Adeno-associated virus	< 4.8	Yes	Yes and episomal	Long-term	Low
Herpes simplex virus 1	35	Yes	No	Long	High
Retrovirus	≤ 8	No	Yes, random	Long-term	Low
Lentivirus	≤ 8	Yes	Yes, into active genes	Long-term	Low
Baculovirus	> 20	Yes	No	Transient	Low
Plasmid-naked	Large	Yes	No	Short	Low
Plasmid-polymer	Large	Yes	No	Short	Low
Plasmid-lipid (liposomes)	Large	Yes	No	Short	Low