TGFB1 and colitis: The IMP-administered WT mice were weakly responsive to TNBS-induced colitis and intestinal fibrosis compared with the controls, displaying reduced weight loss, colonic shortening, inflammation-associated histological scores, Sirius red staining, and downregulated colonic expression of Collagen I, α-SMA, p-Smad2/3, TGFβ1, IL-1β, and TNFα, as well as decreased immunofluorescence staining of Collagen I and α-SMA in the colons (Figure 4B–M).