IL21 and inflammatory bowel disease: Salzer, E.; Kansu, A.; Sic, H.; Májek, P.; Ikincioğullari, A.; Dogu, F.E.; Prengemann, N.K.; Santos-Valente, E.; Pickl, W.F.; Bilic, I.; Ban, S.A.; Kuloğlu, Z.; Demir, A.M.; Ensari, A.; Colinge, J.; Rizzi, M.; Eibel, H.; Boztug, K. Early-onset inflammatory bowel disease and common variable immunodeficiency-like disease caused by IL-21 deficiency.