Aberrant vessel projection in CAGp-ephrin-B2 Tg mice.

Embryonic vasculature in the head region of an E11 wild-type littermate (A), a CAGp-ephrin-B2 Tg/+ embryo (B), a CAGp-ephrin-B2 Tg/Tg embryo (C), and a Tie-2p-ephrin-B2 Tg embryo (H) was visualized by whole-mount immunohistochemistry with the anti–PECAM-1 antibody. (A) Wild-type embryo showing well-developed vascular networks of branches from the ICA (arrowheads) and branches of the ACV (arrows). Note disorganization of the ACV (arrow in B and C) and large-diameter vessels (arrowheads in B and C) in the head of the CAGp-ephrin-B2 Tg mouse. (G) Hemorrhage (arrows) was observed in Tie-2p-ephrin-B2 Tg mice. (H) No disorganization of the ACV and large-diameter vessels in the head of Tie-2p-ephrin-B2 Tg mice. Intersomitic vessels of the trunk at lumbar levels were visualized with the PECAM-1 antibody (D-F, I). A wild-type embryo showing a segmental pattern of intersomitic vessels (arrowheads in D). CAGp-ephrin-B2 Tg mice show the abnormal vessel sprouts penetrating into somites (arrows in E and F), while Tie-2p-ephrin-B2 Tg mice show a normal segmental pattern of intersomitic vessels (arrowheads in I). Top in panels D-F and I is the ventral side. Bars indicate 50 μm.