TLR4 and colitis: Importantly, this phenomenon was not observed after passive transfer of LPS-primed Gal-3−/−DCs, indicating a crucial importance of Gal-3 for TLR-4-dependent activation of IDO-1/KYN pathway in DCs and for DCs-induced expansion of colon-infiltrated Tregs during the alleviation of DSS-induced colitis.