Release of nitric oxide during the T cell-independent pathway of macrophage activation. Its role in resistance to Listeria monocytogenes.

摘要: Immunodeficient mice are remarkably resistant to Listeria monocytogenes (LM) infection. We examined the role that nitric oxide (NO.) plays in CB-17/lcr SCID (SCID) response LM. spleen cells produced large quantities of NO. (as measured by nitrite formation) when incubated presence heat-killed production was dependent on release IFN-gamma NK cells. When tested directly, macrophages LM, but only IFN-gamma. The induced LM not affected neutralizing antibodies TNF or IL-1. inhibited addition either two inhibitors NO.synthase, NG-monomethyl arginine, aminoguanidine. In a different situation, were stimulated and products did produce NO.. Macrophages cultured with killed live This increased killing significantly amino-guanidine. vivo, administration aminoguanidine resulted marked increase mortality bacterial loads LM-infected immunocompetent control mice. conclude is critical effector molecule T cell-independent natural resistance as studied mouse, NO.-mediated essential for both host survive after