The differential growth of virulent and avirulent strains of rinderpest virus in bovine lymphocytes and macrophages.

Rinderpest virus (RV) grew readily in cultures of purified bovine peripheral blood lymphocytes and udder macrophages. The growth of three strains of RV was compared and there appeared to be a relationship between increasing virulence and increased ability to infect lymphocytes and macrophages. The proportion of infected cells as determined by the presence of virus antigens was a better indicator of affinity between a strain and cell type than production of new infectious virus. RV grew better in populations of predominantly T lymphocytes than in T-depleted cultures. Although RV could infect 100% of cells in macrophage monolayers, it did not appear to infect more than about 30% of cells in lymphocyte cultures. Virulent RV grew more readily in bovine than caprine or ovine lymphocytes, whereas virulent peste des petits ruminants virus (PPRV) grew better in lymphocytes from sheep and goats. There was no marked difference in the growth of either virus in lymphocytes from uninfected or recently convalescent animals.