The roles of Nramp1 and Tnfa genes in nitric oxide production and their effect on the growth of Salmonella typhimurium in macrophages from Nramp1 congenic and tumor necrosis factor-alpha-/- mice.
The macrophages from Nramp1 congenic mice and tumor necrosis factor (TNF)-alpha(-/-) mice were used to examine the functions of Nramp1 and Tnfa genes in nitric oxide (NO) production and Salmonella typhimurium infection. It was confirmed that the level of inducible NO synthase (iNOS)-mediated NO production in Nramp1(r) peritoneal macrophages was generally higher than that of Nramp1(s) macrophages after stimulation by interferon-gamma (IFN-gamma), lipopolysaccharide (LPS), and tumor necrosis factor-alpha (TNF-alpha) alone or in combination. Nramp1 mRNA expression in both Nramp1 congenic macrophages was constitutive notwithstanding cytokine stimulation. During infection with S. typhimurium strain 6203, Nramp1(r) macrophages produced a lower amount of NO because of an initial strong reaction and unsustained iNOS gene expression as compared with Nramp1(s) macrophages. An inhibitory effect of the Nramp1(r) gene on bacterial replication was also observed during the early stage of S. typhimurium infection, whereas the effect of TNF-alpha occurred later. NO production and iNOS expression in TNF-alpha(-/-) macrophages were not detected from the start of the bacterial infection or at 24 h after infection. We also observed that S. typhimurium strain 6203 grew more profoundly without TNF-alpha, especially in Nramp1(s) macrophages. These data, therefore, demonstrate that there is cooperation of the Nramp1 and Tnfa genes in NO production and a growth inhibitory effect in response to S. typhimurium infection.
Ables
G P
GP
Laboratory of Experimental Animal Science, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
Takamatsu
D
D
Noma
H
H
El-Shazly
S
S
Jin
H K
HK
Taniguchi
T
T
Sekikawa
K
K
Watanabe
T
T
D000818:Animals; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology; D027682:Cation Transport Proteins; D003114:Colony-Forming Units Assay; D016207:Cytokines / Q000502:physiology; D008262:Macrophage Activation / Q000276:immunology; D017737:Macrophages, Peritoneal / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology; D051379:Mice; D020297:Mice, Congenic; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D018345:Mice, Knockout; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D012333:RNA, Messenger / Q000096:biosynthesis; D012486:Salmonella typhimurium / Q000254:growth & development* / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000172:deficiency* / Q000235:genetics*; D000099173:Natural Resistance-associated Macrophage Protein 1
D002352:Carrier Proteins; D027682:Cation Transport Proteins; D016207:Cytokines; D008565:Membrane Proteins; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D000099173:Natural Resistance-associated Macrophage Protein 1; C496317:Nos2 protein, mouse