Jongseon Choe
Kangwon National University, South Korea
Title: Opposing roles of TGF-β in prostaglandin production by human follicular dendritic cell-like cells
Biography
Biography: Jongseon Choe
Abstract
Prostaglandins (PGs) are recognized as important immune regulators. Using human follicular dendritic cell (FDC)-like HK cells, we have investigated the immunoregulatory role of PGs and their production mechanisms. The present study was aimed at determining the role of TGF-β in IL-1β-induced cyclooxygenase-2 (COX-2) expression by immuno-blotting. COX-2 is the key enzyme responsible for PG production in HK cells. TGF-β, when added simultaneously with IL-1β, gave an additive effect on COX-2 expression in a dose-dependent manner. However, TGF-β inhibited IL-1β-stimulated COX-2 expression when it was added at least 12 hours before IL-1β addition. The inhibitory effect of TGF-β was specific to IL-1β-induced COX-2 expression in HK cells. The stimulating and inhibitory effects of TGF-β were reproduced in IL-1β-stimulated PG production. Based on our previous results of the essential requirement of ERK and p38 MAPKs in TGF-β-induced COX-2 expression, we examined whether the differential activation of these MAPKs would underlie the opposing activities of TGF-β. The phosphorylation of ERK and p38 MAPKs was indeed enhanced or suppressed by the simultaneous treatment or pre-treatment, respectively. These results suggest that TGF-β exerts opposing effects on IL-1β-induced COX-2 expression in HK cells by differentially regulating activation of ERK and p38 MAPKs.
Figure 1: TGF-β has an opposite effect on IL-1β-induced COX-2 expression by controlling phosphorylation levels of ERK and p38 MAPK depending on the treatment time.
References:
1. Jongseon Choe (2016) Opposing roles of TGF-β in prostaglandin production by human follicular dendritic cell-like cells. Molecular Immunology 76:41-48.