ABSTRACT
<p><b>OBJECTIVE</b>To study the inhibitory effect of dexamethasone (DEX) on myeloid differentiation factor 88 (MyD88) and tumor necrosis factor-alpha (TNF-alpha) expression in mouse peritoneal macrophages in innate immune response to Penicillium marneffei (PM).</p><p><b>METHODS</b>Mouse peritoneal macrophages were cultured in the presence of heat-inactivated yeast-phase PM with or without DEX, and the protein and mRNA expressions of MyD88 in the macrophages were detected using Western blotting and real-time PCR, respectively. TNF-alpha in the cell culture supernatant was measured with enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>DEX suppressed TNF-alpha production by the macrophages co-cultured with PM. The expressions of MyD88 were up-regulated by PM stimulation, whose effect was inhibited by the application of DEX.</p><p><b>CONCLUSION</b>The inhibitory effect of DEX on PM-induced proinflammatory responses of the macrophage is directly associated with the inhibition of MyD88 expression.</p>
Subject(s)
Animals , Male , Mice , Cells, Cultured , Dexamethasone , Pharmacology , Macrophages, Peritoneal , Cell Biology , Metabolism , Mice, Inbred BALB C , Myeloid Differentiation Factor 88 , Genetics , Metabolism , Penicillium , Tumor Necrosis Factor-alpha , Genetics , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the differential expression of isocitrate lyase in Penicillium marneffei phagocytized by nonstimulated and stimulated murine macrophages, and explore the role of glyoxylate pathway in pathogenesis of Penicilliosis marneffei.</p><p><b>METHODS</b>Penicillium marneffei conidia and Raw264.7 cells were incubated in 16 cultures, which were divided to 4 groups for treatment with N-monomethyl-L-arginine (LNMMA, CI group), murine interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS) (T group), IFN-gamma plus LPS and LNMMA (TI group), or the same volume of culture medium (C group). The transcriptional levels of isocitrate lyase were detected using real-time RT-PCR, and its expression levels detected biochemically.</p><p><b>RESULTS</b>The transcriptional levels of isocitrate lyase in C, CI, T, TI groups were 1.00, 1.42, 33.09, and 74.88 (P<0.05), while the expression levels were 0.06, 0.07, 0.18, and 0.93, respectively (P<0.05). The content of nitric oxide in T group was significantly higher than that in the other groups (P<0.01), but the CFU of T group was the lowest (P<0.01).</p><p><b>CONCLUSION</b>Reactive nitrogen intermediates induced by stimulated murine macrophages restrain the expression of isocitrate lyase of Penicillium marneffei and development of Penicillium marneffei, in which process the glyoxylate pathway may play an important role.</p>
Subject(s)
Animals , Mice , Cell Line , Fungal Proteins , Genetics , Gene Expression Profiling , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Fungal , Host-Pathogen Interactions , Interferon-gamma , Pharmacology , Isocitrate Lyase , Genetics , Lipopolysaccharides , Pharmacology , Macrophages , Allergy and Immunology , Microbiology , Nitric Oxide , Allergy and Immunology , Penicillium , Genetics , Allergy and Immunology , Physiology , Phagocytosis , Allergy and Immunology , Reverse Transcriptase Polymerase Chain Reaction , omega-N-Methylarginine , PharmacologyABSTRACT
Objective To investigate the dynamic distribution changes of fungi responsible for the deep infection and antifungal susceptibility to provide a basis for the empirical antifungal treatment.Methods Medical records were reviewed from cases suspectedof deep fungal infection at our hospital from January 1998 to December 2004.3122 isolates of 13 species were analyzed with SPSSll.0.Etest was used for the antifungal susceptibility test.Results Candida albicans was the most commonly isolated organism,while the prevalence of Candida albicans decreased(76.3% vs 66.8%,x~2=34.33,P
ABSTRACT
To assay the influence of dendritic cells(DCs)on the function of anti-infective immunity to Penicillium marneffei.DCs were generated from peripheral blood mononuclear cells(PBMC)and pulsed with Penicillium marneffei yeasts.DCs morphology was observed by the inverted microscope and cell surface markers of DCs were analyzed by flow cytometry.The concentrations of IL-12p70 were detected by ELISA. Mixed lymphocyte reaction was performed to assay the proliferation of T cells.The mRNA of CCR7 and CXCR4 were detected by the Real-time PCR quantifications.The acquired DCs exhibited irregular appearance and numerous long dendrites under light microscope.DCs and Penicillium marneffei yeasts were co-cultured for 24 h,numerous yeasts were observed inside the cells;an enhanced expression of the cell sur-face markers CD86、CD83、HLA-DR and CD40 were demonstrated;the expression of CCR7 and CXCR4 mRNA were also increased;the improved proliferation of T cells were observed in the mixed lymphocyte reaction.Yeasts-pulsed DCs secreted more IL-12p70 than that of non-pulsed,but less than that of LPS-pulsed DCs.DCs can engulf the Penicillium marneffei yeasts.When pulsed with Penicillium marneffei yeasts,DCs improved their expression of the co-stimulatory molecules and chemokine receptor CCR7、CXCR4,enhanced their capacity to process antigen.DCs play an important role in host defense against Penicillium marneffei infection.But the low level of the IL-12p70 production may lead to deficiency in the cell-mediated immunity against Penicillium marneffei.