Anti-CD36 autoantibodies in thrombotic thrombocytopenic purpura and other thrombotic disorders: identification of an 85 kD form of CD36 as a target antigen
Dr. Schultz et al., Anti-CD36 autoantibodies in thrombotic thrombocytopenic purpura and other thrombotic disorders: identification of an 85 kD form of CD36 as a target antigen, BR J HAEM, 103(3), 1998, pp. 849-857
The presence of anti-CD36 antibodies in plasma of patients with thrombotic
thrombocytopenic purpura (TTP), idiopathic thrombocytopenic purpura (ITP),
and heparin-induced thrombocytopenia without/with thrombosis (HIT/HITT) has
been examined by immunoblots, and a monoclonal antibody capture assay, the
platelet-associated IgG characterization assay (PAICA). Results with PAICA
showed that 73% (8/11) of patients with TTP were positive, and 71% (10/14)
by immunoblots. With ITP, 20% (6/30) were positive by PAICA and 19% (3/16)
by immunoblots; HIT, 30% (3/10) were positive by PAICA and 60% (6/10) by i
mmunoblot; HITT. 50% (2/4) by PAICA and 100% (4/4) by immunoblot. Purificat
ion of CD36 by fast protein liquid chromatography (FPLC) from Triton X-100
extracts of normal platelet membranes resulted in the isolation of two diff
erent forms: the classic 88 kD form, and a second, lighter 85 kD form. Our
data indicated that the patients' plasma autoantibodies reacted strongly wi
th the 85 kD form. Conventional monoclonal and polyclonal antisera produced
to the 88 kD form reacted strongly with the 88 kD form but weakly with the
85 kD form. These results confirm the possible importance of anti-CD36 ant
ibodies in the pathophysiology of TTP and other thrombocytopenias and demon
strate the presence of a previously unrecognized target antigen for these a
ntibodies.