Short report: Inhibition by tumor necrosis factor-alpha-activated macrophages of the transition of Paracoccidioides brasiliensis conidia to yeast cells through a mechanism independent of nitric oxide.
It is known that peritoneal murine macrophages activated with interferon-gamma exert a fungicidal effect against Paracoccidioides brasiliensis conidia by a nitric oxide (NO)-mediated mechanism. This NO-mediated effect can also be induced by other cytokines such as tumor necrosis factor-alpha (TNF-alpha). The aim of this study was to determine if TNF-alpha-activated peritoneal murine macrophages infected with P. brasiliensis were able to show fungistatic/fungicidal effects mediated by NO. The results indicated that although macrophage activation with TNF-alpha did not result in NO production, these cells played an important role in inhibiting the conidia from becoming yeast cells. In vivo, the NO-independent inhibitory effect would prove of importance for the establishment of P. brasiliensis in host tissues.
Gonzalez
Angel
A
Medical and Experimental Mycology Group, Corporación para Investigaciones Biológicas, Medellín, Colombia. agonzalezm@cib.org.co
Aristizábal
Beatriz H
BH
Gómez
Erika Caro
EC
Restrepo
Angela
A
Cano
Luz E
LE
D000818:Animals; D008018:Life Cycle Stages; D008262:Macrophage Activation / Q000276:immunology*; D017737:Macrophages, Peritoneal / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000378:metabolism; D010228:Paracoccidioides / Q000254:growth & development / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology*
D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide