Fig. 4. Incorporation of cultured epidermal cells into the vasculature. Cultured epidermal progenitor cells (B) and transient amplifying cells (A) were labeled with CM-DiI (red fluorescent dye) and injected into a mouse ischemic hindlimb. Five weeks later, biopsies of ischemic muscles were immunostained for CD31 (to identify endothelial cells; green). CM-DiI-labeled (red) cells, co-labeled CM-DiI and anti-CD31 (yellow) cells can be seen in the vessels. No injected cells (red) could be seen in the vasculature (green) in the contralateral control muscle (C). Scale bars, 25 µm.