MODULATION BY TUMOR NECROSIS FACTOR OF INFLAMMATORY MOLECULES IN LPS-STIMULATED MURINE MACROPHAGES

JERÉZ M B, ; MAYORDOMO A C; ARIAS JL; JURIAYUB M ; DI GENARO M S

Estancia Grande, San Luis

Congreso; XXXII Reunión annual de la Sociedad de Biología de Cuyo; 2014

ociedad de Biología de Cuyo

Tumor necrosis factor (TNF) is a pleiotropic cytokine primary synthesized by macrophages. TNF acts through two transmembrane receptors: TNFRp55 and TNFRp75. We previously demonstrated increased interleukin (IL)-6 and nitric oxide (NO) production after stimulation with LPS of TNFRp55 deficient macrophages compared with wild-type C57BL/6 macrophages. The purpose was to analyze the molecular mechanisms by which TNF might regulate these inflammatory mediators using murine macrophage cell line RAW 264.7. Since this cell line was established in BALB/c mice, we added IFN-d in the cellular culture and analyzed the effect of TNF on the production of IL-6 and NO by stimulation with LPS. We found that IFN-g or LPS stimulation triggers TNF production, and that simultaneous IFN-g and LPS stimulation did not change this effect. Moreover, we observed that IL-6 and NO was induced by IFN-g (10 ng/ml) plus LPS (100 ng/ml). To analyze the effect of TNF, the cells were pre-incubated at different concentrations and incubation time with human TNF which has demonstrated to be specific for murine TNFRp55. We found that in contrast with NO, 30 and 90 ng of TNF reduced the IL-6 production induced by stimulation with LPS/IFN-g. We conclude that the cell line RAW 264.7 may be used to analyze the molecular mechanisms involved in a possible regulatory role of TNF on other inflammatory molecules produced by murine macrophages.