Fig. 8

HA-iMSC-EVs increases blood vessel density and improves left ventricular remodeling after I/R injury. a, b Immunohistochemical staining for Cardiac Troponin T (TNNT2, green) and CD31 (red) in the border zone (upper) and infarct zone (lower) (a) and quantification of capillary density and a number of cardiomyocytes (b). c, d Representative images from the four experimental groups showing cardiac fibrosis after staining with Masson’s trichrome in the hearts harvested 5 weeks after I/R injury (purple and blue, scar tissue; red, viable myocardium, c) and quantification of the viable myocardium area and fibrosis area (d). n = 4–5 animals per group. * p < 0.05, compared to the PBS treatment group; † p < 0.05, compared to the 2 times 10 mg injection group by one-way ANOVA. Error bars show means ± SEM. n = 4–5 animals per group