Platelet antibodies in serum of patients with human immunodeficiency virus (HIV) infection.

Between 10 and 15% of human immunodeficiency virus (HIV) seropositive individuals develop an immune thrombocytopenic purpura; however, the mechanism involved in platelet destruction is not yet established. In the present work, we have analyzed 208 sera from HIV seropositive individuals, including 85 thrombocytopenic patients, for the presence of autoantibodies against platelet proteins by using the Western blot technique. Our results indicate that: (1) antibodies against platelet proteins were found in 8 of 123 (6.5%) nonthrombocytopenic patients, as compared with 17 of 85 (20%) of thrombocytopenic patients (p less than 0.03); (2) these antibodies appeared to be more frequently found in advanced stages of disease (p less than 0.02); (3) the reactivity of positive sera with antigenic determinants implicated several distinct platelet proteins; (4) antigens thus recognized are unrelated to the major membrane glycoproteins IIb and IIIa, as well as absent in vero cells and trypsin-sensitive cells. Such results underscore the difficulties in establishing the mechanisms involved in platelet destruction during HIV infection.