Abstract: The present invention relates to the discovery of a novel retroviral particle associated with autoimmune disease. New methods of diagnosis and treatment of autoimmune disease, novel cell lines comprising the new retrovirus, assay systems that may be used in the development of antiretroviral pharmaceuticals, and model systems for the study of autoimmune diseases and acquired immunodeficiency syndrome (AIDS) are provided by the present invention.

Abstract: The present invention relates to purified preparations of a novel retrovirus, to methods of diagnosis and treatment of Sjogren's syndrome, novel cell lines, and model systems for the study of autoimmune diseases and AIDS. It is based, in part, on the discovery of a novel retrovirus which is antigenically similar to human immunodeficiency virus but which appears to comprise a functionally distinct reverse transcriptase.According to the present invention, Sjogren's syndrome as well as other autoimmune diseases, may be diagnosed, and their clinical course may be monitored, by demonstrating the presence of anti-retroviral antibodies and/or measuring the levels of such antibodies. Alternatively, Sjogren's syndrome or other autoimmune diseases may be diagnosed or monitored by directly or indirectly demonstrating vital particles in the cells of a patient.