Vasculature induced by Ad-VEGF-DΔNΔC in skin.

Focal areas of hypodermis taken from rat 1 week after subdermal injection with PBS (A, D, G), Ad-GFP (B, E, H), or Ad-VEGF-DΔNΔC (C, F, I). Hematoxylin and eosin–stained tissue sections are shown (A-C); ×20 objective. (A) Small tuft of vessels primarily composed of veins with surrounding monocytes, lymphocytes, and macrophages. (B) Irregular, small veins with some signs of inflammation. (C) Venous channels with extremely irregular branching, consistent with an area of vascular proliferation. Tissue sections were stained for laminin (D-F) or VEGFR-2 (G-I). Dramatic increase in the density of laminin and VEGFR-2–positive blood vessels as a result of Ad-VEGF-DΔNΔC injection is evident. Panels D-I, ×40 objective.