Studies on the interaction between coxsackievirus A9 and HeLa cells. II. Mode of growth of coxsackievirus A9 in HeLa cell cultures and the effect of sulfated polysaccharide on plaque formation.

For the purpose of clarifying the mechanism of plaque formation in HeLa cell cultures by coxsackievirus A9, which does not show definite CPE in fluid cultures, we investigated the growth pattern of the virus in HeLa cells, comparing plaque (HeLA)-forming and non-plaque (HeLa)-forming viruses. It was revealed that the yield of both viruses per cell was nearly the same, but non- plaque (HeLa)-forming virus was far less efficient in infecting HeLa cells. Dextran sulfate was effective in releasing more virus from cells, when HeLa cell cultures were infected with plaque (HeLa)-forming virus, but not in cultures infected with non-plaque (HeLa)-forming virus. From these experimental results, the mechanism by which plaques are formed in HeLa cell cultures by coxsackievirus A9 was discussed.