Flow cytometry and microscopy analysis of rat adipose-derived mesenchymal stem cells and histopathological scoring of renal injury. Flow cytometric analysis and microscopy findings of rat adipose-derived mesenchymal stem cells (ADMSCs) (n = 6) and histopathological scoring of acute kidney ischemia–reperfusion (IR) injury at 72 hours after the IR procedure (n = 8). Upper panel: (A) Flow cytometric results of rat ADMSCs and endothelial progenitor cells (EPC) on day 14 after cell culturing showed that CD90+ cells contributed the highest population of stem cells (n = 6). (B) Spindle-shaped morphology of stem cells illustrated in the lower right corner (200×). (C) Percentage of ADMSCs and EPC shown was the mean value of n = 6. Lower panel: (A) to (D), (G) to (K) H & E staining (200× in (A) to (E), and 400× in (G) to (K)) of kidney sections in sham control, IR, IR + cyclosporine (CsA), IR + ADMSCs and IR + CsA + ADMSCs, showing significantly higher degree of loss of brush border in renal tubules (yellow arrowheads), cast formation (green asterisk), tubular dilatation (blue asterisk), tubular necrosis (green arrows), and dilatation of Bowman’s capsule (blue arrows) in the IR without treatment group than in other groups at 72 hours after IR procedure. (F) *P <0.0001 vs. other groups with different symbols; † vs. ‡ vs. ¶ vs. §, all P <0.05 for inter-group comparisons. All statistical analyses were with one-way analysis of variance followed by Bonferroni multiple comparison post-hoc test. Different symbols (*, †, ‡, ¶, §) among different groups indicate significance (at 0.05 level). Scale bars in right lower corner = 50 μm.