MADCAM1 and colitis: Neutralizing MAdCAM-1 abrogated the effects of optogenetic activation on the clinical symptoms of DSS-induced colitis in the ChR2/TH mice (weight loss: p = 0.0470 for isotype control group and p = 0.2939 for anti-MAdCAM-1 group; colon shortening: p = 0.0015 for isotype control group, and p = 0.1654 for anti-MAdCAM-1 group; histological score: p = 0.3761 for anti MAdCAM-1 group; Figures 5B–5E).