Neutrophil surface markers in patients with acute leukemia

The presence of complement and Fc receptors on neutrophils from patients with acute leukemia was investigated at different stages of the leukemic process. Both Fc receptors (Fc-H and Fc-R) and one complement receptor (C3d) were normal when patients were studied at diagnosis, in relapse, and in remission. In contrast, the C3b receptor was significantly reduced on te neutrophils at the time of diagnosis, but returned to normal levels when patients entered remission. Variable amounts of C3b activity were observed in patients relapse, with approximately one-half of the patients showing decreased C3b activity. To determine whether the reduction inC3b receptors was specific for patients at diagnosis, three patients were studied at different times during their diseases. Normal receptor levels were detected in these patients during remission, but the C3b receptor was markedly reduced at diagnosis and at relapse.