Figure 3.

EndMT in COL4A3-deficient mice. (A) Kidneys of COL4A3 KO mice, a mouse model for Alport syndrome, were analyzed at the age of 22 wk. The pictures display representative photomicrographs of MTS-stained kidney sections at an original magnification of ×10 (left) and ×60 (middle). Fibrosis was digitally quantified and is shown as the percentage of MTS-stained blue area in both normal and COL4A3 KO kidneys (right). (B, left) FSP1 and CD31 double labeling. Kidney sections were double stained with antibodies to FSP1 (green) and CD31 (red). DAPI was used as a nuclear stain (blue). The panels display representative images that were obtained from COL4A3 KO kidneys (top) and normal kidneys (bottom). The arrows in the merged panel point to CD31⁺FSP1⁺ cells. (B, right) α-SMA and CD31 double labeling. The pictures display representative photomicrographs of kidneys that were labeled with antibodies to α-SMA (green) and CD31 (red). DAPI was used for labeling of nuclei (blue). Yellow color in the merged panel indicates coexpression of α-SMA and CD31. (C) Quantification of fibroblasts. The bar graphs summarize average number of FSP1⁺ fibroblasts, CD31⁺FSP1⁺ cells, α-SMA⁺ fibroblasts, and CD31⁺α-SMA⁺ cells per visual field in both normal and Alport kidneys at a magnification of ×63 (n = 3 mice per group, 10 hpf per mouse, 30 hpf total). Magnification, ×63 in B.