Polymyositis in an immunodeficiency disease in monkeys induced by a type D retrovirus.

Fifty percent of primates with acquired immunodeficiency caused by a well-characterized type D retrovirus (SAIDS D) developed clinical, laboratory, and histologic features of polymyositis. By use of specific antisera and immunochemical techniques, we found the virus in the lymphoid cells surrounding muscle fibers and invading the endomysia septa. SAIDS D virus was isolated from the involved muscles and infected myotubes of normal muscle in tissue culture. These results suggest that retroviruses, a group of viruses increasingly associated with human diseases, can cause polymyositis with immunodeficiency in nonhuman primates and could play a role in human polymyositis.