Detection and analysis of antibodies against retrovirus determinants in the sera of haematologic patients.

A panel of 11 retroviruses including animal retroviruses types B, C, D and human retroviruses HTLV-I and HTLV-III was used as antigen for detection of antibodies in 265 sera of patients suffering from haematologic and autoimmune diseases and in 98 control sera. In contrast to the control sera, the 39 patients sera contained antibodies against internal proteins of animal retroviruses types B and C. No antibodies against human retroviruses proteins or type D retrovirus core proteins were detected. The antibodies from positive sera immunoprecipitated the RNA from polyribosomal fraction of R-MuLV infected spleen cells which also showed positive hybridization with a specific cDNA probe. The antibodies in patients' sera were directed mainly against RNA-binding proteins p15 of type C or p14 type B virus. The retrovirus antigenic determinants were expressed also in human embryo haemopoietic cells. The possible interpretation of antibody formation against the determinants of animal retroviruses in humans is discussed.