EPHB4 and colitis: Given the increased levels of ephrin-B2 mRNA in the gut mucosal lesions of CD patients (Hafner et al., 2005), we then asked whether similar changes in the expression of ephrin-B2 ligand and of its preferential binding protein, the EphB4 receptor, occurred in TNBS-induced colitis: as a result, comparable levels of EphB4 mRNA and protein were detected in the colon of normal and colitic mice.