Effects of prostaglandin E-2 and nitric oxide inhibitors on the expressionof interleukin-10, interleukin-12 and MHC class-II molecules in Mycobacterium microti-infected and interferon-gamma-treated mouse peritoneal macrophages

Mycobacterium microti-infected mouse peritoneal macrophages produced high a mounts of prostaglandin E-2 (PGE(2)) and nitric oxide (NO) when activated w ith interferon-gamma (IFN-gamma), In order to understand the relation betwe en PGE(2) and NO production and the expression of interleukin-12 (IL-12), i nterleukin-10 (IL-10) and MHC class-11 (Ia) molecules by M. microti-infecte d and IFN-gamma -stimulated macrophages, we analyzed the level of these mol ecules in the presence or absence of PGE(2) and NO inhibitors. Addition of N-G-methyl-L-arginine (L-NMA) and indomethacin (IM) caused a significant in crease in IL-12 level (2.6- and 1.9-fold, respectively) whereas IL-10 level decreased by 88 and 56%, respectively. relative to M. microti-infected and IFN-gamma -treated control macrophages, Enhanced PGE(2) and NO upregulated IL-10 expression and down-regulated IL-12 and MHC class-II (Ia) expression in W. microti-infected and IFN-gamma -treated mouse peritoneal macrophages .