title: Attempts to characterize the mechanisms involved in the growth inhibition of Mycobacterium microti in interferon-gamma or tumor necrosis factor-alpha activated J774A.1 cells.
abstract: The growth of Mycobacterium microti was inhibited within J774A.1 macrophage cells activated with either interferon-gamma or tumor necrosis factor-alpha. Activation with interferon-gamma or tumor necrosis factor-alpha alone did not stimulate the production of nitrite in J774A.1 cells. Interferon-gamma but not tumor necrosis factor-alpha increased the production of hydrogen peroxide in a concentration dependent manner but scavengers of reactive oxygen species did not influence the growth inhibiting effect of interferon-gamma within J774A.1 cells. Both interferon-gamma and tumor necrosis factor-alpha enhanced the fusion of M. microti containing phagosomes with lysosomes and the ultimate degradation of bacteria. Our results showed that growth inhibition of M. microti within interferon-gamma or tumor necrosis factor-alpha stimulated J774A.1 cells was independent of reactive oxygen intermediate and reactive nitrogen intermediate production.
authors.affiliation: Institute of Microbial Technology (CSIR), Chandigarh, India.
authors.forename: R
authors.initials: R
authors.lastname: Gupta
authors.forename: N
authors.initials: N
authors.lastname: Dogra
authors.forename: M
authors.initials: M
authors.lastname: Raje
authors.forename: S
authors.initials: S
authors.lastname: Majumder
mesh_terms: D000818:Animals; D002455:Cell Division; D002460:Cell Line; D007371:Interferon-gamma / Q000494:pharmacology*; D008247:Lysosomes / Q000382:microbiology / Q000648:ultrastructure; D008262:Macrophage Activation / Q000276:immunology* / Q000502:physiology; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D008561:Membrane Fusion; D051379:Mice; D008854:Microscopy, Electron; D009161:Mycobacterium / Q000254:growth & development* / Q000276:immunology* / Q000472:pathogenicity; D009584:Nitrogen / Q000378:metabolism; D010588:Phagosomes / Q000382:microbiology / Q000648:ultrastructure; D017382:Reactive Oxygen Species / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D009584:Nitrogen