Effects of antifungal agents on the function of human neutrophils in vitro

Abstract

Polymorphonuclear leukocytes (PMNs) are an important component of the host defense against fungi. We investigated the influence of five antifungal agents on PMN function and compared them with amphotericin B (AmB). The in vitro effects of AmB, flucytosine, ketoconazole, fluconazole, Sch-39304, and cilofungin (LY121019) on chemotaxis, phagocytosis, oxidative metabolism of PMN as reflected by superoxide anion (O2-) generation, and intracellular killing of Candida albicans blastoconidia were examined. With regard to chemotaxis in response to N-formylmethionyl-leucyl-phenylalanine, as measured by the multiwell chamber method, AmB induced a marked decrease (greater than or equal to 5 micrograms/ml), whereas ketoconazole at 5 micrograms/ml enhance it. Phagocytosis was significantly decreased after pretreatment of PMNs with AmB and Sch-39304 (greater than 5 and 1 to 10 micrograms/ml, respectively). O2- production after stimulation of PMNs with N-formylmethionyl-leucyl-phenyl-alanine was significantly decreased by AmB (greater than 5 micrograms/ml) and enhanced by Sch-39304 (1 to 5 micrograms/ml). In contrast, intracellular killing, as tested by methylene blue staining, was enhanced by ketoconazole (5 micrograms/ml) and Sch-39304 (1 to 5 micrograms/ml). Flucytosine, fluconazole, and cilofungin did not affect PMN function at therapeutic concentrations. The results of this comprehensive study indicate that AmB, flucytosine, cilofungin, and the newer azoles, at safely achievable concentrations, generally do not suppress PMN function at therapeutic enhance selective functions.