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Name:	Shanthi Sitaraman
Position:	Associate Professor of Medicine Associate Professor of Pathology and Laboratory Medicine
Degree:	M.D., University of Toronto, 1992 Ph.D., University of Toronto, 1989 F.R.C.P., University of Toronto, 1995
Programs:	BCDB, Full Member MSP, Full Member
Phone:	404-727-2430
Address:	205F Whitehead Research Bldg, 615 Michael St, 1941/001/1AK
Email:	ssitar2@emory.edu
Research Descriptions:
Short:	Pathogenesis of Inflammatory Bowel Disease; mechanisms of diarrhea in IBD.
Long:	Our laboratory is interested in both the basic science and clinical aspects of IBD. Our research focuses on the understanding of the pathogenesis of IBD, particularly the mechanisms of diarrhea in IBD. Many intestinal disorders, particularly the acute flare of IBD, are characterized by migration of neutrophils across the intestinal epithelium into the lumen to form ¿crypt abscess¿. Crypt abscesses are pathognomic of active IBD as well as infectious colitis and correlates with the severity of disease as well as clinical symptoms. Our earlier studies have shown that when neutrophils migrate into the intestinal lumen during inflammation, they release 5¿AMP which has been identified as the major secretogogue that induces chloride secretion in intestinal cells. 5¿AMP-induced chloride secretion is mediated by adenosine which is released into the intestinal lumen upon conversion of 5¿AMP to adenosine by apically located 5¿ectonucleotidase. We have shown that adenosine acts through adenosine 2b receptor, a G-protein coupled receptor, which when activated increases intracellular cAMP and subsequently activates CFTR to induce vectorial chloride secretion. This forms the basis of secretory diarrhea that is seen during intestinal inflammation. Adenosine also induces polarized IL-6 secretion and IL-6, in turn, activates neutrophils. Since adenosine plays a central role in orchestrating chloride secretion in response to neutrophil transmigration, the general goal of our work is to characterize the biology of the adenosine receptor and the direct neutrophil-epithelial interaction mediated by adenosine. Our research involves characterization of the adenosine 2b receptor and its signaling pathways and development of novel approaches to the treatment of IBD. We also have animal models of IBD in which we test potential therapeutic agents for IBD.