Inhibition of vesicular stomatitis virus in cells constitutively expressing an antisense RNA targeted against the virus RNA polymerase gene.

To study the effect of virus-specific antisense RNA expression on vesicular stomatitis virus (VSV) infectivity in cultured cells, a HeLaS3 cell line constitutively expressing antisense RNA complimentary to a portion of the VSV large RNA-dependent RNA polymerase gene (L) was established (HeAntiL). At an m.o.i. of 0.01 or 0.1, the HeAntiL cell line was able to reduce virus titre and delay virus-induced cell death by 9 or 5 h, respectively, when compared to a HeLa cell line stably transfected with the expression vector devoid of antisense sequence. Ribonuclease protection experiments showed a 10-20-fold reduction of hybridizable virus L mRNA in infected HeAntiL cells compared to infected control cells at various times before cell death. These results indicate that the antisense RNA approach can significantly reduce VSV mRNA transcription and virus production for a reasonable period of time. The robust growth rate of VSV eventually overwhelms the available antisense RNA and leads to delayed cell death.