Sa. Dryga et al., CONSTRUCTION AND INVESTIGATION OF RECOMBI NANT STRAINS OF VENEZUELAN EQUINE ENCEPHALOMYELITIS VIRUS EXPRESSING PRES(2)-S GENE OF HEPATITIS-B VIRUS, Voprosy virusologii, 41(3), 1996, pp. 100-104
Venezuelan equine encephalomyelitis (VEE) virus-based vectors for expr
ession of heterologous genes have been constructed using full-length c
DNA copy of the interstrain recombinant virus (Trinidad Donkey and 230
strain). Gene cassettes carrying the subgenomic mRNA promoter of VE v
irus and the pre(2)-S gene of hepatitis B virus (HBV) were inserted be
fore or after the genes of structural viral proteins. Live virus stock
s were obtained by transfection of chick embryo fibroblasts with in vi
tro transcribed full-length RNA. Insertions of gene cassettes before t
he structural region resulted in expression of HBsAg (VEHB-25 and VEHB
-361 viruses), whereas insertions ill the 3' region did not. recombina
nt virus VEHB-25 expressed HBsAg during 5 passages in Vero cells. VEHB
-25 stimulated immune response to HBsAg and was less virulent than the
parental virus.