Pathogenesis of K papovavirus infection in athymic nude mice.

The fatal outcome of K virus infection in infant mice and cytoxan-treated adult mice is related to their inability to mount a prompt antibody response to the virus. Athymic nude mice infected with K virus exhibited no clinical illness and no detectable virus-specific immunoglobulin G (IgG) response, but they did exhibit a low level of virus-specific immunoglobulin M response. Transfer of spleen cells from K virus-primed nude mice to infected infant mice conferred complete protection against K virus-induced mortality. This protection was diminished by the depletion of B cells but not by the depletion of adherent cells from the primed spleen cells. B cell response is therefore important in the recovery of nude mice from K virus infection.