Lentiviral-mediated stable knockdown of VEGFR2 in hAR and mAR models. (A) Graph reports VEGFR2 expression in hAR-sprouted cells extracted from BME. hARs are transduced with lentiviruses carrying VEGFR2-targeted shRNA (shVEGFR2_87 and shVEGFR2_88) and scramble shRNA (shSRCL), or not infected (notINF). VEGFR2 mean fluorescence signals of VEGFR2-positive cells are shown and expressed as relative percentage of VEGFR2 levels of shSCRL hARs (*P < .05 vs shSCRL hARs; **P < .01). (B-C) Quantifications and representative micrographs of hARs transduced with lentiviruses carrying VEGFR2-targeted shRNA (shVEGFR2_87 and shVEGFR2_88) and scramble shRNA (shSRCL) or not infected (notINF). hARs were observed after 15 days of EGM-2 culture and are representative of 3 experiments, each from 6 umbilical cords. Values shown are box-and-whisker plots of sprout lengths normalized to the median of shSCRL hARs. Scale bar represents 200 µm (*P < .05 vs shSCRL hARs). (D) Graph showing VEGFR2 expression in mAR-sprouted cells extracted from BME. VEGFR2 mean fluorescence signals of VEGFR2-positive cells are shown and expressed as relative percentage of VEGFR2 levels of shSCRL mARs (*P < .05 vs shSCRL mARs). (E-F) Quantifications and representative micrograph of mARs transduced with lentiviruses carrying VEGFR2-targeted shRNA (shVEGFR2_69 and shVEGFR2_70) and scramble shRNA (shSCRL). mARs were observed after 5 days of EGM-2 culture and are representative of 3 experiments, each from 5 different mice. Values shown are box-and-whiskers plots of sprout lengths, normalized to the median of shSCRL mARs. Scale bar = 200 µm (*P < .05 vs shSCRL mARs).