butaprost and Arthritis

Interleukin-23, a recently described cytokine produced by activated antigen-presenting cells, including dendritic cells, is a p19/p40 heterodimer. The p40 subunit is shared with IL-12, the major Th1-driving cytokine, while p19 is distantly related to IL-12 p35. IL-23 has pro-inflammatory actions, inducing IL-17 secretion from activated CD4+ T cells, and stimulating the proliferation of memory CD4+ T cells. Here, we examined the effects of PGE2, a well-known immunomodulator, on the production of IL-23 by bone marrow- derived dendritic cells (BM-DCs). Our results indicate that PGE2 increases the production of functional IL-23 from immature BM-DCs in a time- and dose-dependent manner. PGE2 induces both the expression of p19 and p40, without affecting p35 expression. The effect of PGE2 is mediated through the specific receptors EP2/4 and is mimicked by cAMP-inducing agents, such as forskolin and dbcAMP. Although PGE2 also induces IL-1beta and IL-6 expression in non-stimulated DCs, the stimulatory effect of PGE2 on IL-23 production is not mediated through IL-1beta or IL-6. GM-CSF, the pro-inflammatory cytokine required for the generation of BM-DCs, amplifies the IL-23 inducing activity of PGE2 in a synergistic manner. Recent studies described both pro- and anti-inflammatory effects of PGE2, and our results suggest an additional mechanism for its pro-inflammatory role, particularly significant for autoimmune diseases, such as rheumatoid arthritis.

Topics: Alprostadil; Animals; Arthritis; Bone Marrow Cells; Bucladesine; CD4-Positive T-Lymphocytes; Cell Line, Tumor; Cells, Cultured; Colforsin; Culture Media, Conditioned; Cyclic AMP; Dendritic Cells; Dinoprostone; Gene Expression Regulation; Inflammation; Interleukin-12; Interleukin-12 Subunit p35; Interleukin-12 Subunit p40; Interleukin-17; Interleukin-23; Interleukin-23 Subunit p19; Interleukins; Lipopolysaccharides; Male; Mice; Misoprostol; Plasmacytoma; Prostaglandin Antagonists; Protein Subunits; Receptors, Cell Surface; Second Messenger Systems; Specific Pathogen-Free Organisms; Toll-Like Receptor 2; Toll-Like Receptor 4