IL17A and colitis: Our results show that TNF-ɑ and IL-17A protein levels are significantly increased during the inflammatory process, and HA-PLGABilirubin hydrogels can significantly reduce the expression of these two proteins (Figure S15), indicating that HA-PLGABilirubin hydrogel may repair DSS-induced colitis by negatively regulating the TNF and IL-17 signaling pathways.