Acquired immunodeficiency syndrome in a colony of macaque monkeys.

Abstract

A naturally occurring immunodeficiency syndrome was seen in a captive colony of macaque monkeys. This syndrome was seen primarily in the species Macaca cyclopis. Affected animals died with lymphomas (a rare disease in macques) or such opportunistic infections as Pneumocystis carinii and noma (necrotizing gingivitis). These M. cyclopis exhibited anemia, neutropenia and a circulating bizarre immature monocyte. Liver functions tests suggested hepatitis. Pokeweed mitogen-, concanavalin A- and xenogeneic cell-stimulated proliferative responses by lymphocytes of animals with the syndrome were dramatically diminished. The T4 (helper, inducer)/T8 (suppressor, cytotoxic) ratio in the peripheral blood mononuclear T-cell populations of M. cyclopis in this colony are decreased when compared with those from either M. mulatta in the same colony or normal humans. Epidemiologic evidence implicates a common source agent in this syndrome. The similarity of this syndrome in macaques to human acquired immunodeficiency syndrome suggests that it may provide an important model for studying the human syndrome.