Biogenesis of poxviruses: Transitory expression of Molluscum contagiosum early functions

Inoculation of primate cells with Molluscum contagiosum (MC) produces extreme cell rounding, aggregation, and surface convolutions termed cytopathic effect (CPE). The CPE is transitory, completely reversible, and temporally connected with formation of virus-specified RNA and antigen. The early functions are expressed from the inoculum virus cores which are released into the host cytoplasm but never become uncoated. Although cores persist for at least 10 days, the cells are completely viable, regain their normal form, and remain susceptible to reinfection with MC. Attempts at rescuing MC uncoating by means of coinfection with vaccinia, Yaba, and Shope fibroma viruses or inoculation of differentiating keratinocytes from explants of human epidermis, were unsuccessful. It is, therefore, most likely that MC replication is blocked in vitro because the agent is unable to pass through the uncoating phase.