DEFECTIVE POLYMORPHONUCLEAR LEUKOCYTE FUNCTIONS IN CHILDREN RECEIVINGCHEMOTHERAPY FOR CANCER ARE PARTIALLY RESTORED BY RECOMBINANT HUMAN GRANULOCYTE-COLONY-STIMULATING FACTOR IN-VITRO

Granulocyte colony-stimulating factor (G-CSF) has important direct and priming effects on different functions of normal mature polymorphonuc lear leukocytes (PMNL). Previous study has shown an alteration in resp iratory burst and bactericidal activities of PMNL harvested from child ren with cancer treated with chemotherapy. The present study evaluates the possibility that recombinant human (rh) G-CSF could correct these defective functions in vitro, Free radical formation in defective PMN L was enhanced by rhG-CSF to a level similar to that found in normal P MNL primed by rhG-CSF. The defective bactericidal activity against Esc herichia coli and Staphylococcus aureus was also corrected. This bacte ricidal activity was not different from that observed in normal PMNL p rimed by rhG-CSF. In conclusion, correction of the altered free radica l-formation pathway by rhG-CSF in these cells contributed to the resto ration of normal bactericidal activity against both gram-positive and gram-negative microorganisms.