Autoimmune diseases in humans, e.g. autoimmune rheumatic diseases

In spite of increasing evidence that viruses and especially retroviruses could act as etiologic factors in autoimmune and especially autoimmune rheumatic diseases, clear-cut evidence for an involvement of these agents is still missing. Findings, which, for example, indirectly support the hypothesis that retroviruses might play a part, are the demonstration of antibodies to the gp24 in SLE and Sjögren's patients as well as the description of retroviral antigens in the inflamed synovium of rheumatoid arthritis patients. Furthermore, evidence comes from animal models that viruses, such as the Visna or Caprine arthritis encephalitis virus, induced chronic inflammatory diseases in sheep and goats. More recently, a mouse model for rheumatoid arthritis and Sjögren's syndrome was reported in mice transgenic for HTLV-1tax. It is hoped that, especially from the experimental animal models, the possible role of retroviruses as etiological factors in autoimmune rheumatic diseases can be clarified.