Autoimmunity and Neoplasia: The Possible Role of C-type Viruses

Abstract

Viruses have been implicated in autoimmune disease in animals and man. C-type RNA tumor viruses induce neoplasia in a variety of animals, but their role in human malignancy is unknown. An unusual C-type virus has been isolated from New Zealand black mice which have an inherited disease syndrome consisting of both autoimmune phenomena and neoplasia. This virus cannot be propagated in mouse cells but does grow in cells foreign to the host species. For this reason, it has been termed a xenotropic murine leukemia virus. Similar viruses have been detected at less frequency and lower titers in NIH Swiss and other mouse strains. Since horizontal infection in the host is unlikely, this xenotropic virus must represent an endogenous virus of mice. Because of its prevalence in NZB mice, particularly during embryonic life, its role in causing both autoimmune disease and malignancy is proposed. The possibility of a human xenotropic virus is also discussed.