Fig. 4

Histopathology analysis of tissues from rhesus macaques. Pathological changes were observed under a light microscope (a) and transmission electron microscope (b). Normal rhesus macaque glomerulus and tubes (a, f, k, p, and u); rhesus macaques with DN before normal saline infusion (b, g, l, q, and v) or MSC transplantation (d, i, n, s, and x). Further expanded mesangial matrix and progressive peritubular interstitial fibrosis after normal saline infusion (c, h, m, r, and w), and ameliorated glomerular basement membranes, mesangial matrix, and peritubular interstitial fibrosis after MSC transplantation (e, j, o, t, and y). The arrows and red asterisks represent pathological areas. c–g Quantified renal histological indices before and 1 month after NS or MSC transplantation. GBM: glomerular basement membrane; NS: normal saline; MSCs: mesenchymal stem cells. Scale bar of pictures in a: 50 μm; magnification of TEM: 1.2 k. Each bar represents the mean ± s.e.m. Four fields of each section, four sections per rhesus macaque were observed and quantified, and the number of rhesus macaques was analyzed in each group: Normal (n = 3), DN + NS (n = 4), DN + MSCs (n = 6). *p < 0.05, **p < 0.01: before versus after in DN + MSC group. #p < 0.05, ##p < 0.01, ###p < 0.001: DN + NS group versus DN + MSC group after NS or MSC transplantation