Growth of Newcastle disease virus in a HVJ carrier culture of HeLa cells

Abstract

Growth of Newcastle disease virus (NDV) in a HVJ carrier culture of HeLa cells (HeLa HVJ) was investigated. Although most of the cells of the carrier culture contained HVJ antigen, its presence did not interfere with the growth of superinfecting NDV. When HeLa HVJ cells were infected with NDV at a low multiplicity of infection, the yield of progeny virus was higher, and the cytopathic changes were more extensive than those in normal HeLa cells. Plaques produced by NDV on HeLav HVJ cell monolayers were clearer and larger than those on HeLa cells. HeLa HVJ cells could be distinguished from normal HeLa cells both with respect to production of interferon and sensitivity to its action. Production of interferon which normally appeared in HeLa cell culture infected with NDV could not be demonstrated in HeLa HVJ cell culture. The cells of HeLa HVJ were less susceptible to the antiviral action of interferon than normal HeLa cells.