Fig. 4

Evaluation of candidate vascular cells for TGF-β1 expression. All immunofluorescence images are from PAD patients who present with tissue loss and are representative of all diseased patients in our study. a TGF-β1 labeling (green) does not co-localize with CD163 positive macrophages (red) present at relatively high density in the adventitia of microvessels. High magnification of the boxed region reveals cellular labeling of CD163 around DAPI stained nuclei (blue). b TGF-β1 labeling (green) does not co-localize with CD3 positive T cells (red) that are located typically around myofibers near microvessels. High magnification of the boxed region reveals cellular labeling of CD3 around DAPI stained nuclei (blue). c TGF-β1 labeling (green) does not co-localize with CD31 positive endothelial cells (red) that are characteristically located in the intima of microvessels. d TGF-β1 labeling (green) does not co-localize with TE-7 positive fibroblasts (red). e TGF-β1 labeling (green) co-localizes with high molecular weight caldesmon (h-Caldesmon) a specific marker of smooth muscle cells (red). Arrows point to rhomboidal morphology characteristic of secretory SMC. f The proliferation marker Ki-67 (green) is expressed in nuclei (blue) of h-Caldesmon positive SMC (red) that highly express TGF-β1 as determined with a neighboring tissue section