TLR-9 activation has been shown to prevent development of mucosal inflammation and promote wound healing in several models of experimental colitis; however, there was also some controversy in the beginning because some authors proposed a CpG-dependent contribution to the perpetuation of chronic intestinal inflammation.9,12–16 In UC patients, a positive correlation between the severity of endoscopic and histological inflammation and TLR-9 expression could be found.13,17. Here, TLR9 is linked to gastroenteritis.