title: Analysis of the antimicrobial responses of primary phagocytes of the goldfish (Carassius auratus L.) against Mycobacterium marinum.
abstract: The slow growth rate of Mycobacterium spp. that infect humans coupled with a lack of reliable in vitro infection model systems has hindered the progress of research in host cell-mycobacteria interactions. Recent studies have utilized the relatively fast growing Mycobacterium marinum to examine the host-pathogen interface in natural fish hosts. Here we describe the use of primary goldfish monocyte and mature macrophage cultures to investigate the immune cell-M. marinum interactions. Live and heat-killed M. marinum abrogated the recombinant goldfish (rg)TNFα2 and rgIFNγ-induced monocyte reactive oxygen production. Live but not heat-killed M. marinum also ablated rgIFNγrel and rg-TNFα2 induced macrophage nitric oxide production. M. marinum induced significant changes in gene expression of select NADPH oxidase components and inflammatory cytokine receptors and up-regulated the expression of immunosuppressive genes IL-10, TGFβ1 and SOCS-3. The exposure of monocytes and mature macrophages to M. marinum caused an increase in the mRNA levels of several pro-inflammatory genes. Stimulation of monocytes and macrophages with rgTNFα2, rgIFNγ, or rgIFNγrel reduced the survival of intracellular mycobacteria. The characterization of the interaction between M. marinum and natural host-derived primary phagocyte cultures will enable future studies on the host-pathogen interactions in mycobacterial infections.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Leon
authors.initials: L
authors.lastname: Grayfer
authors.forename: Jordan W
authors.initials: JW
authors.lastname: Hodgkinson
authors.forename: Miodrag
authors.initials: M
authors.lastname: Belosevic
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D006054:Goldfish / Q000276:immunology* / Q000382:microbiology; D054884:Host-Pathogen Interactions; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology; D016753:Interleukin-10 / Q000096:biosynthesis; D008264:Macrophages / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D019910:Mycobacterium marinum / Q000276:immunology*; D019255:NADPH Oxidases / Q000096:biosynthesis; D009569:Nitric Oxide / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism; D018121:Receptors, Cytokine / Q000096:biosynthesis; D050826:Suppressor of Cytokine Signaling Proteins / Q000096:biosynthesis; D053773:Transforming Growth Factor beta1 / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology
chemical_list: D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D018121:Receptors, Cytokine; D050826:Suppressor of Cytokine Signaling Proteins; D053773:Transforming Growth Factor beta1; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D009569:Nitric Oxide; D007371:Interferon-gamma; D019255:NADPH Oxidases