Gamma interferon cooperates with lipopolysaccharide to activate mouse splenic macrophages to an antihistoplasma state.
AUTOR(ES)
Lane, T E
RESUMO
Inhibition of the intracellular growth of Histoplasma capsulatum by murine resident red pulp splenic macrophages was examined. Splenic macrophages, unlike resident peritoneal macrophages, required a prolonged preincubation (18 h) with recombinant murine gamma interferon (rMuIFN-gamma) for activation. To be fully activated, the splenic macrophages required incubation with rMuIFN-gamma in combination with 0.1 microgram of lipopolysaccharide (LPS) per ml. Splenic macrophages stimulated with rMuIFN-gamma, LPS, or rMuIFN-gamma and LPS produced tumor necrosis factor alpha (TNF-alpha), but recombinant murine TNF-alpha (rMuTNF-alpha) did not activate macrophages when used alone or as a second signal with rMuIFN-gamma. Anti-TNF-alpha antibody did not block IFN-gamma-LPS activation of splenic macrophages to any significant extent. One hundred micromolar ferrous sulfate antagonized IFN-gamma-LPS activation of splenic macrophages, indicating that iron was involved in the fungistatic activity of cytokine-stimulated phagocytes. Our results indicate that (i) splenic macrophages differ significantly from peritoneal macrophages in their requirements for activation and (ii) the mechanism by which splenic macrophages exert their antifungal effects involves iron.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=281387Documentos Relacionados
- Iron limitation and the gamma interferon-mediated antihistoplasma state of murine macrophages.
- Antihistoplasma effect of activated mouse splenic macrophages involves production of reactive nitrogen intermediates.
- Transforming growth factor beta 1 and gamma interferon provide opposing signals to lipopolysaccharide-activated mouse macrophages.
- Capacity of recombinant gamma interferon to activate macrophages for Salmonella-killing activity.
- Kinase-negative mutants of JAK1 can sustain interferon-gamma-inducible gene expression but not an antiviral state.