DLL4 and cerebral cavernous malformation: To define the association of CCM3 and DLL4 expression in the endothelial layer of CCM covens, immunofluorescent staining of CCM3, DLL4 and vWF was simultaneously performed on adjacent sections from the CCM3-mutation carrier (Mu-CCM3; Fig. 3D–F) and from sporadic CCM (Sp-CCM; Fig. 3H–J).