Modulation of neutrophil-mediated activity against the pseudohyphal form of Candida albicans by granulocyte colony-stimulating factor (G-CSF) administered in vivo

Renewed interest in neutrophil transfusions has emerged with the developmen t and clinical use of granulocyte colony-stimulating factor (G-CSF). G-CSF not only increases neutrophil (polymorphonuclear leukocyte, PMNL) productio n but also modulates various physiological properties of PMNL. The effects of G-CSF on PMNL-mediated fungicidal activity were evaluated by administrat ion of G-CSF (300 mu g/day subcutaneously) to 5 healthy volunteers for 6 da ys. G-CSF significantly enhanced PMNL-mediated damage of Candida albicans p seudohyphae by 33% (P = .007) on day 2 and by 44% (P = .04) on day 6 at a 1 0:1 effector:target ratio. In contrast, the ability of PMNL to induce damag e of hyphae from either Fusarium solani or Aspergillus fumigatus did not si gnificantly change during the study period, These data demonstrate that G-C SF administered in vivo modulates PMNL-mediated fungicidal activity against the pseudohyphal form of C. albicans, thereby suggesting potential utility of G-CSF as a biologic response-modifying therapy in some opportunistic fu ngal infections.