Rapid Communication Isolation of SV40 from the environment of a colony of cynomolgus monkeys naturally infected with the virus

AbstractThe presence of SV40 viral particles in the environment of cynomolgus monkeys naturally infected with this virus has been analyzed bytesting waste of the cage samples.SV40 was detected in 2/4 cages tested where mixed infection of SV40 and adenoviruses was observed after inoculation of virionsconcentrated from cage waste in CV-1 cells. The detected SV40 strains were identical in the regions studied to strain W17, isolated atNational Institute for Biological Standards and Control, UK (NIBSC) from a (1/19) monkey kidney biopsy and contains an archetypalregulatory region. The recovery of infectious SV40 virions from the cages provides information about the potential mechanism oftransmission of this virus.D 2004 Elsevier Inc. All rights reserved. Keywords: SV40; Environment; Cynomolgus; SV40 infection; SV40 stability; SV40 transmission IntroductionThe discovery of the polyomavirus SV40 is tied to thedevelopment and distribution of polio vaccines that wereinadvertently contaminated with the virus and distributedworldwide potentially exposing several millions of personsto the virus during 1955–1963 (Shah and Nathanson, 1976).SV40 naturally infects a few species of Asiatic macaques,especially Rhesus monkeys (revised in Shah et al., 1971). Inrhesus macaques, the virus multiplies readily producingviremia and a high-tittered antibody response. In the wild,only a small proportion of the juvenile macaques, but nearlyall adults, have SV40 antibodies (Meyers et al., 1962; Shahand Southwick, 1965). This infection appears to besubclinical, and the virus establishes a long-term latentchronic infection in the kidneys and is excreted in the urineproviding an opportunity for environmental contaminationand transmission to nonimmune monkeys although the exactmanner of transmission of SV40 is not known (Hull, 1968).Experimentally, nonimmune rhesus monkeys are readilyinfected by the oral, intranasal, and subcutaneous routeleading to viremia and viruria. In captivity, SV40 is readilytransmitted to other macaques in contact with infectedrhesus as is the case for cynomolgus macaques and Africangreen monkeys (Shah and Nathanson, 1976). The presenceof SV40 in the brain of immunodeficient monkeysdemonstrated that SV40 is neurotropic in addition to beingkidney tropic. A role for SV40 in the etiology of some braintumors and in the development of central nervous systemlesions distinct from PML has been suggested (Hurley et al.,1997; Simon et al., 1999). Recently, reports linking SV40and human tumors have accumulated, and the potential roleof SV40 in cancer etiology requires serious consideration.SV40 has been associated with mesotheliomas and differenttypes of brain tumors such as ependymomas and choroidplexus carcinomas. In addition to mesotheliomas and braintumors, SV40 has been associated with other human tumors