TJP1 and colitis: Sun et al., with RT-PCR studies on Rag1−/− DSS colitis mice (which lack T and B cells) treated with liraglutide, demonstrated the significant upregulation of the following IL-22-dependent genes: Ltbr, Il18, and RegIIIβ, while the expression of Glp1r, Tjp1 (encoding the tight junction protein ZO-1), and Il23 remained unchanged.