Purpose To determine whether ephrin B2plays a role in ocular angiogenesis,we investigated the expression of ephrinB2and EphB receptors on retin al fibroproliferative membranes.Design Experimental stu dy of the express...Purpose To determine whether ephrin B2plays a role in ocular angiogenesis,we investigated the expression of ephrinB2and EphB receptors on retin al fibroproliferative membranes.Design Experimental stu dy of the expression of ephrinB2and EphB receptors within f ibroproliferative membranes in patients with ocular an giogenic diseases collected during vitrectomy.Methods Fibroproliferative membranes were obtained at the time o f vitrectomy from 20patients with proliferative diabetic retinopathy(PDR)and from 40patients who had stage 5retin opathy of prematu-rity.Specimens were investigated w ith immunohistochem-istry using polyclonal antibodies d irected against ephrinB2and the EphB2,EphB3,and EphB4recep tors.Im-munoreactivity for von Willebrand f actor(factor VIII)andα-smooth muscle actin(α-SMA)was also determined to confirm the identity of the target va scular endothelial cells.Results Positive staining for ephrinB2was observed on fibroproliferative membranes that were obtained from pa-tients with PDR(65.0%)and retinopathy of prematurity(25.0%).Specifically,ephrinB2was found t o be present on endothelial cells,as confirmed b y its colocalization with factor VIII andα-SMA staining.EphB2and EphB3ex-pression was observed on fibroproliferative membranes that were harvested from patients with PD R(EphB2,90.0%;EphB3,70.0%)and retinopathy of prematurity(EphB2,35.0%;EphB3,45.0%).However,EphB4expression was not observed in any of the membran es derived from patients with PDR or retinopathy of prematurity.The rate of ephrinB2expression in patients with PDR was significantly higher than that seen in patients with retinopathy of pre-maturity,which probably reflected differences in the vas-cular density of their fibroprolife rative membranes.Con-clusion These data suggest that the e phrinB2-EphB2/B3system may play an important role in o cular angiogenesis.展开更多
文摘Purpose To determine whether ephrin B2plays a role in ocular angiogenesis,we investigated the expression of ephrinB2and EphB receptors on retin al fibroproliferative membranes.Design Experimental stu dy of the expression of ephrinB2and EphB receptors within f ibroproliferative membranes in patients with ocular an giogenic diseases collected during vitrectomy.Methods Fibroproliferative membranes were obtained at the time o f vitrectomy from 20patients with proliferative diabetic retinopathy(PDR)and from 40patients who had stage 5retin opathy of prematu-rity.Specimens were investigated w ith immunohistochem-istry using polyclonal antibodies d irected against ephrinB2and the EphB2,EphB3,and EphB4recep tors.Im-munoreactivity for von Willebrand f actor(factor VIII)andα-smooth muscle actin(α-SMA)was also determined to confirm the identity of the target va scular endothelial cells.Results Positive staining for ephrinB2was observed on fibroproliferative membranes that were obtained from pa-tients with PDR(65.0%)and retinopathy of prematurity(25.0%).Specifically,ephrinB2was found t o be present on endothelial cells,as confirmed b y its colocalization with factor VIII andα-SMA staining.EphB2and EphB3ex-pression was observed on fibroproliferative membranes that were harvested from patients with PD R(EphB2,90.0%;EphB3,70.0%)and retinopathy of prematurity(EphB2,35.0%;EphB3,45.0%).However,EphB4expression was not observed in any of the membran es derived from patients with PDR or retinopathy of prematurity.The rate of ephrinB2expression in patients with PDR was significantly higher than that seen in patients with retinopathy of pre-maturity,which probably reflected differences in the vas-cular density of their fibroprolife rative membranes.Con-clusion These data suggest that the e phrinB2-EphB2/B3system may play an important role in o cular angiogenesis.
