Administration of SEW2871 improves VEGF-driven angiogenesis in vivo. Mice were treated daily with SEW2871, beginning on day 2 after implantation of the VEGF165-transfected cells in Matrigel. (A) As shown grossly at day 7, SEW2871 improved formation of neovessels (scale bar = 450 μm). In addition, as viewed in cross-sections stained for CD31, neovessels with well-developed lumens were most abundant in the SEW2871 group. S indicates skeletal muscle layer; V, vessels, M, Matrigel; scale bar = 25 μm. (B) Quantification of vascular parameters (n > 20 for all groups). From gross images: relative neovascularization, (ie, percentage of relative area occupied by neovessels in flat mount, P < .001). From CD31-stained cross-sections: quantification of ECs per 0.01 mm2 relative total lumen area (P < .001), numbers of neovessels per 0.015 mm2 and average internal neovessel diameter (P < .001).