Vascular occlusion and vasculopathy underlie much of the morbidity in patients with sickle
cell anemia. Platelets may play a role in this vasculopathy. Samples from 12 adult patients
with sickle cell anemia were examined for evidence of platelet activation and formation of
platelet-erythrocyte aggregates (PEA) using fluorescent-labeled monoclonal antibodies and
flow cytometry. We noted an increased expression of activation-dependent antigens on the
platelets from patients with sickle cell anemia compared with those from both white and …