Dil-Ac-LDL uptake by myoendothelial cells located in the interstitial spaces of leech skeletal muscle and recruited by VEGF injection.

(A–C) Cryosections of unlesioned (A) and injured (B, C) leeches injected with Dil-Ac-LDL. Samples were processed 1 week after treatment. Dil⁺ cells (red) are visible dispersed in the ECM surrounding the groups of muscle fibres (m) in control animal (A), close to the regenerating area (arrowhead in B) and in the lumen of vessels (v in C) in the injured leeches. (D–F) Cryosections of a VEGF/Dil-Ac-LDL injected leech. After one week from injection new vessels (D) and cells incorporating the vital colorant Dil-Ac-LDL (red in D, E) are visible under the epithelium (e) in the injected area. In control PBS/DIL injected areas, few Dil⁺ cells (red in F) are present under the epithelium (e). Nuclei are counterstained with DAPI (blue in A, B, D–F). Bars in A, B: 100 µm; Bar in D–F: 50 µm.