Nitric oxide production by TNFRp55-/- macrophages after Yersina outer membrane or recombinant OmpC porin stimulation.

PARAPUÑO F; ELICABE RJ; JURI AYUB M; DI GENARO MS

Mendoza

Congreso; XXVIII Reunion de la Sociedad de Biologia de Cuyo; 2010

Sociedad de biología de Cuyo

Nitric oxide (NO) is associated with chronic inflammation. We previously demonstrated that TNFRp55-/- mice develop Yersinia enterocolitica-induced arthritis, and outer membrane (OM) is the relevant fraction triggering this arthritis. Porins are the major OM proteins. The objectives were to obtain a recombinant Yersinia porin, OmpC, and to compare NO production by TNFRp55-/- and wild-type macrophages after OM or OmpC stimulation. OmpC was obtained by transforming Escherichia coli BL21(DE3)pLysS cells with a recombinant plasmid containing ompC gene. Hexa-histidine tagged recombinant OmpC was expressed and purified by affinity chromatography. Peritoneal macrophages from wild-type and TNFRp55-/- C57BL/6 mice were stimulated with OM (1 ƒÝg/ml) or OmpC (2 or 4 ug/ml). Supernatant NO was measured by Griess reaction. Recombinant OmpC was characterized as a protein of 38 kDa. OM induced significant higher levels of NO in TNFRp55-/- compared with wild-type macrophages (p<0.05).  In contract, OmpC induced decreased NO levels in TNFRp55-/- macrophages (p<0.05). We concluded that TNFRp55 signaling influences NO production induced by Yersinia OM components.