![Figure 4. Integrin β3 is required for VSMC coverage in developmental angiogenesis. (A) Representative images of retinas undergoing early postnatal retinal developmental angiogenesis at 3 different time points: P3, P5, and P7. Mice with deficient downstream αvβ3 signaling (DiYF) have less arterial VSMC coverage at each time point than age-matched wild-type (C57BL/6) controls. Retinas were immunostained with isolectin GS-IB4 from Griffonia simplificonia (lectin, red) to label the endothelium and αSMA to label VSMCs (green). (B) VSMC coverage was measured along each artery as a percentage of the outgrowth of the vascular plexus (dotted lines). Arterial coverage is reduced by 30% at p3, 22% at p5, and 14% at P7. (C-D) Intravitreal injection of blocking Abs against integrin β3 (D) reduces arterial αSMA staining compared with control (C). (E) The β3 function-blocking Ab reduced arterial VSMC coverage by 74% (P = .01). Values represent means ± SEM. C57BL/6 (n = 12 [P3], n = 23 [P5], n = 19 [P7]), DiYF (n = 15 [P3], n = 23 [P5], n = 21 [P7]), isotype control-injected, n = 5; anti-β3 injected, n = 6, where n is the number of retinas analyzed. For the DiYF time course, P = 1.4 × 10−4 (P3), P = 7.5 × 10−9 (P5), P = 1.0 × 10−3 (P7). Scale bars: (A) 150 μm (P3), 300 μm (P5), 600 μm (P7); and (C-D) 50 μm.](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/119/9/10.1182_blood-2011-04-348706/4/zh89991185040004.jpeg?Expires=1735505982&Signature=j-I-z2GBrjreqM3NaheNyp~Y30jyXCgyvvwwDw7QaNOmCt0mWBFJdh6r4V0fBEOs~r~z5hBpCEAvErIh7s-9kXzNOWP2Ia08EMsuGxPejdWrQC-927SH1M50Ce1OV4W1gOQvV6431zwU3LDZ-jZw3fxtLqhQyLKEV7jcEhTgVGgl~qixT7nbfqbR0KMqgOUTuEo~W-b7PS6zsWhBK-EpgctIPSz4sXChXsG-VFEBBnKjOoiF6ZdjFzPFiAdhvgRvjRHjuTUtkkjy9MCk4uNVJkhr1AJ46EB-ji7~A8RPxLLr1TY~6bggGids4DU3s~vHXV5ct07hbd6gMwxloLYmWg__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Integrin β3 is required for VSMC coverage in developmental angiogenesis. (A) Representative images of retinas undergoing early postnatal retinal developmental angiogenesis at 3 different time points: P3, P5, and P7. Mice with deficient downstream αvβ3 signaling (DiYF) have less arterial VSMC coverage at each time point than age-matched wild-type (C57BL/6) controls. Retinas were immunostained with isolectin GS-IB4 from Griffonia simplificonia (lectin, red) to label the endothelium and αSMA to label VSMCs (green). (B) VSMC coverage was measured along each artery as a percentage of the outgrowth of the vascular plexus (dotted lines). Arterial coverage is reduced by 30% at p3, 22% at p5, and 14% at P7. (C-D) Intravitreal injection of blocking Abs against integrin β3 (D) reduces arterial αSMA staining compared with control (C). (E) The β3 function-blocking Ab reduced arterial VSMC coverage by 74% (P = .01). Values represent means ± SEM. C57BL/6 (n = 12 [P3], n = 23 [P5], n = 19 [P7]), DiYF (n = 15 [P3], n = 23 [P5], n = 21 [P7]), isotype control-injected, n = 5; anti-β3 injected, n = 6, where n is the number of retinas analyzed. For the DiYF time course, P = 1.4 × 10−4 (P3), P = 7.5 × 10−9 (P5), P = 1.0 × 10−3 (P7). Scale bars: (A) 150 μm (P3), 300 μm (P5), 600 μm (P7); and (C-D) 50 μm.
