In regard to the fact that both intestinal mucosa and PBMC lnc-ITSN1-2 are found to be closely correlated with risk, severity, and inflammation response of IBD in our study, and CD4+ T cell activation, proliferation and differentiation are key bioprocesses of IBD development and progression, we hypothesized that lnc-ITSN1-2 might regulate IBD CD4+ T cell functions. Here, ITSN1 is linked to inflammatory bowel disease.