HUMAN ENDOGENOUS RETROVIRUSES - NATURE, OCCURRENCE, AND CLINICAL IMPLICATIONS IN HUMAN-DISEASE

Retroviral diagnostics have become standard in human laboratory medici ne. While current emphasis is placed on the human exogenous viruses (h uman immunodeficiency virus and human T-cell leukemia virus), Evidence implicating human endogenous retroviruses (HERVs) in various human di sease entities continues to mount. Literature on the occurrence of HER Vs in human tissues and cells was analyzed. Substantial Evidence docum ents that retrovirus particles were clearly demonstrable in various ti ssues and cells in both health and disease and were abundant in the pl acenta and that their occurrence could be implicated in some of the re productive diseases. The characteristics of HERVs are summarized, mech anisms of replication and regulation are outlined, and the consistent hormonal responsiveness of HERVs is noted. Clear evidence implicating HERV gene products as participants in glomerulonephritis in some cases of systemic lupus erythematosus is adduced. Data implicating HERVs as etiologic factors in reproductive diseases, in some of the autoimmune diseases, in some forms of rheumatoid arthritis and connective tissue disease, in psoriasis, and in some of the inflammatory neurologic dis eases are reviewed. The current major needs are to improve methods for HERV detection, to identify, the most appropriate HERV prototypes, an d to develop diagnostic reagents so that the putative biologic and pat hologic roles of HERVs can be better evaluated.