ACTA1 and colitis: The interstitial myofibroblast with positive α-SMA immune expression was detected in the submucosa of the UC group and lamina propria and submucosa of CO and PCL@CS + ALG groups (hardly detected in the mucosa of the colitis group as the colitis group exhibited extensive and diffused mucosal ulceration with loss of the entire thickness of surface epithelium and crypts.