DETECTION OF ANTIBODIES TO HIV-1 GP41-DERIVED AND HLA CLASS-II ANTIGEN-DERIVED PEPTIDES IN SLE PATIENTS

A role for viruses in the pathogenesis of human autoimmune diseases ha s long been suspected but has not yet been proven. Highly conserved ho mologous regions has been reported in the carboxy terminus of human im munodeficiency virus (HIV)-1 gp41 (amino acids 838-844) and the amino- terminal of the beta chain of all human HLA class II antigens (amino a cids 19-25). This molecular mimicry between HIV-1 and HLA class II ant igens may lead to the generation of autoantibodies and may contribute to the development of autoimmune phenomena in HIV infected patients. W e detected antibodies for these homologous peptides from HLA class II and HIV-1 gp41 in systemic lupus erythematosus (SLE) patients without HIV-I infection. Thirty-seven percent of the SLE patients had IgM anti bodies reacting with both HLA class II- and HIV-1 gp41-derived peptide s. These results suggest the possibility that a retrovirus may be one of the causative agents of SLE.