Neovascularization and α_v integrin expression are features of human GvHD. (A) Representative sections of the IT are shown for patients with or without GvHD. The panels show red immunohistochemical staining for CD31 in the microvasculature. (B) The immunohistochemical analysis for CD31 in the IT of healthy and GvHD patients is shown. CD31 expression is increased in patients with GvHD III°-IV° compared with GvHD I°-II° (P = .001) or patients without GvHD (P = .0001). (C) Histopathological analysis for α_v integrin in the IT of patients with or without GvHD. α_v Integrin expression is preferentially found in ECs of patients with GvHD with brown immunohistochemical staining for α_v integrin in the microvasculature. Representative sections of the IT are shown for healthy and GvHD patients. (D) The immunohistochemical analysis for α_v integrin in the IT of healthy and GvHD patients is shown with an increase of α_v integrin expression in patients with GvHD III°-IV° compared with GvHD I°-II° (P < .001) or patients without GvHD (P < .0001).