Figure 2. Apln-CreER labels active angiogenesis in the ischaemic hindlimb.

(a) Schematic figure showing the experimental strategy for ligation of the left femoral artery and labelling of Apln⁺ cells in Apln-CreER;Rosa26^RFP/+ adult mice. (b) Whole mount picture of hindlimb 2 weeks after ligation or sham. (c) RFP and PECAM immunostaining of sections from ischaemic and sham-operated hindlimbs. White arrowheads indicate RFP⁺PECAM⁺ cells. (d) Percentage of RFP⁺ cells among PECAM⁺ vascular ECs. Analysis of variance was used to analyse differences between groups and values are shown as means±s.e.m.; *P<0.05, n=4. (e) Laser Doppler perfusion assay of ischaemic limbs. (f) Immunostaining of ESR shows Apln-CreER expression in hindlimbs. Scale bars, 1 mm (b); 100 μm (c,f).