GRANULOCYTE FUNCTIONS IN CHILDREN WITH CANCER ARE DIFFERENTIALLY SENSITIVE TO THE TOXIC EFFECT OF CHEMOTHERAPY

To analyze the toxicity associated to chemotherapy upon granulocytes, different functional assays were performed, within days of drug exposu re and at time of bone marrow recovery, on polymorphonuclear neutrophi ls (PMN) from children with cancer. There were no significant postchem otherapy changes in the expression of the different receptors studied nor in the phagocytosis of Staphylococcus aureus 42D. By contrast, a s ignificant decrease was observed in H2O2 production in PMN recently ex posed to chemotherapy with both cytofluorometric and chemiluminescence assays. There was also a decrease in the production of O-2(radical an ion) and in chemotaxis; finally, the intracellular killing of S. aureu s 42D and Escherichia coli was reduced. In patients having recovered f rom drug-induced bone marrow aplasia, PMN functions were found to be n ormal except for bactericidal activity which was still defective. Thes e observations indicate that, in patients exposed to chemotherapy, som e PMN functions are transiently altered, whereas microorganism cell ki lling is continuously impaired.