ANTIBODIES TO RETROVIRAL PROTEINS IN AUTOIMMUNE CONNECTIVE-TISSUE DISEASE - RELATION TO CLINICAL MANIFESTATIONS AND RIBONUCLEOPROTEIN AUTOANTIBODIES

Objective. To study the relationship between antibodies that recognize human retroviral proteins and the presence of clinical features and ribonucleoprotein antibodies in patients with autoimmune connective tissue diseases (CTDs). Methods. Antibodies against native human immunodeficiency virus type 1 (HIV-1) and human T cell leukemia/lymphoma virus type 1, recombinant HIV-1 Nef protein, and ribonucleoprotein antigens were determined by immunoblot of sera from 65 prospectively studied patients with definite or suspected CTDs of autoimmune type. Results. Antibodies to retroviral proteins (ARP), most frequently to HIV Gag proteins p55 and p24, were found in 64% of 22 patients with systemic lupus erythematosus (SLE), in 63% of 8 patients with discoid LE (DLE), in 75% of 8 patients with mixed connective tissue disease (MCTD), and in 26% of 19 individuals with chronic biologically false-positive (CBFP) seroreactions, but not in 8 patients with subacute cutaneous lupus erythematosus. No clear correlation of ARP with antibodies to any specific small nuclear RNP antigen was observed. The most striking finding was that recurrent infections, both in LE patients and in those with CBFP reactions and widespread, acral discoid skin lesions, occurred significantly more often in ARP-positive patients. Conclusion. The occurrence of antibodies reacting with human retroviral proteins is associated with severe skin lesions and recurrent infections in SLE, DLE, and MCTD patients, and with a disposition toward developing systemic disease in CBFP reactors.