GROWTH OF MOLLUSCUM CONTAGIOSUM VIRUS IN A HUMAN FORESKIN XENOGRAFT MODEL

Molluscum contagiosum virus (MCV) is a common pathogen causing a troub lesome skin condition in many immunocompetent individuals and a widesp read, disfiguring affliction in many patients with AIDS. We have succe ssfully infected human foreskin fragments with a patient-derived isola te of MCV. This was demonstrated by exposing the foreskin pieces to a patient lesion extract and implanting the tissue under the renal capsu le of athymic mice. Light and electron microscopic examination or infe cted implants showed the presence of cytoplasmic inclusions containing typical poxvirus particles within 2-3 weeks or implantation. Replicat ion of MCV was established by demonstrating that viable virus was requ ired to produce the cytopathologic effects, and viral DNA replication was demonstrated by incorporation of bromodeoxyuridine into cytoplasmi c inclusions. Four additional patient extracts (representing both desc ribed MCV types) were also used to successfully infect foreskin implan ts. A limited number of attempts to pass virus from one infected impla nt to another were not successful. This system is the most rapid and r eproducible for growing MCV that has been reported to date. (C) 1996 A cademic Press, Inc.