Activation of Src contributes to phosphorylation and internalization of vascular endothelial cadherin (VE‐Cadherin) which loosens the tight junctions and contributes to vascular leakage exacerbating the diabetic retinopathy (Figure 8).[183, 184] Hence, Sema4d sets a nice example of how the crosstalk between retinal glial cells and the pericytes holds critical function to maintain a healthy vasculature in the eye. This evidence concerns the gene CDH5 and diabetic retinopathy.