Disparate regulation of LPS-induced MAPK signaling and IL-12p40 expression between different myeloid cell types with and without HIV infection.

Studies from our laboratory and those of others have implicated lipopolysaccharide (LPS)-induced MAPK signaling as an important pathway in the regulation of cytokine expression. In this article, the regulation of IL-12 expression in two different human myeloid cell populations was evaluated. In primary monocytes, the inhibition of p38 enhanced IL-12 production, whereas it downregulated IL-12 production in THP-1 cells.