Role of superoxide anion in the fungicidal activity of murine peritoneal exudate macrophages against Penicillium marneffei.

摘要: Penicillium marneffei is an important opportunistic fungal pathogen. The mechanisms of host defense against P. are not fully understood. In the present study, we, for first time, investigated role superoxide anion (O2−) in killing two forms marneffei, yeast cells and conidia, this mediator fungicidal activity IFN-γ-stimulated murine peritoneal macrophages. were susceptible to effect activated macrophages chemically generated O2−, while conidia not. These results suggested that O2− played some However, oxygen radical scavenger, dismutase (SOD), did suppress, but rather enhanced cells. This inconsistency was explained by release insufficient concentrations as compared with amount necessary cells, which predicted a chemical generating system. On other hand, SOD production nitric oxide (NO) IFN-γ-activated macrophages, their increased significantly inhibited NG-monomethyl-l-arginine (l-NMMA), competitive inhibitor NO synthase. Our does function plays regulation NO-mediated system suppressing production.