T1717 Gender Influences Intestinal Toll-Like Receptor Expression Under Normal and Inflammatory Conditions

Abstract

the gut lumen and through engulfment by professional (e.g. macrophages) phagocytes. The potential role of non-professional phagocytes, e.g. epithelial cells, fibroblasts, etc., has not been examined within the context of cellular clearance in CD. Work from our laboratory and others have identified a group of molecules shared by both professional and nonprofessional phagocytes as being critical in engulfment of apoptotic targets. These include the phosphatidyl recognition receptor BAI1 and its downstream signaling module ELMO/ Dock180/CrkII/Rac, as well as a second module involving LRP1/GULP/ABCA1. Our microarray data show gene expression of key engulfment molecules in purified murine intestinal epithelial cells (IEC), and protein levels in three human IEC lines. Engulfment assays using apoptotic thymocytes indicate the ability of IECs to engulf In Vitro. This, coupled with their numerical abundance, may represent an important homeostatic mechanism, especially in CD. Furthermore, stimulation of IECs with apoptotic cells results in the active production of the immunosuppressive cytokine TGF-β.