peptidic factors may at least partially explain why Sb has pleiotropic effects on intestinal mucosa and therapeutic effects on such a wide variety of gastrointestinal disorders [9,38,39]. Some of the yet unidentified molecules may interfere with host cell signaling pathways and thereby modulate host cell behavior [38]. Indeed, Sb has been shown to secrete polyamines that are implicated in intestinal cell maturation, enzyme expression and membrane transport mechanisms [38]. In addition, Sb produces other factors that reduce inflammation by blocking NF-kB activation [21,40] and enhancing PPAR-c expression [41]. The motogenic molecule(s) secreted by Sb remain to be elucidated. However, our preliminary data suggest that the motogenic factor(s) secreted by Sb is (are) an heat instable molecule(s) (result not shown). Further studies are now needed to explore the molecular mechanisms by which supernatant of Sb alters cell migration. 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PLoS ONE | www.plosone.org 11 March 2011 | Volume 6 | Issue 3 | e18427