Immunity-and-Matrix-Regulatory Cells Derived from Human Embryonic Stem Cells Safely and Effectively Treat Mouse Lung Injury and Fibrosis

Jun Wu; Dingyun Song; Zhongwen Li; Baojie Guo; Yani Xiao; Wenjing Liu; Lingmin Liang; Chunjing Feng; Tingting Gao; Zai Wang; Jianyan Wen; Shengnan Yang; Peipei Liu; Lei Wang; Yukai Wang; Liang Peng; Guihai Feng; Shiqiang Huang; Glyn Nigel Stacey; Wei Li; Yan Huo; Ronghua Jin; Qi Zhou; Liu Wang; Baoyang Hu; Huaping Dai; Jie Hao

Our scRNAseq results also indicated that more than 99% of IMRCs expressed MMP1 compared with 434 primary UCMSCs (<1%) (Fig. 4A) . Similarly, gene expression analysis by RT-qPCR showed that IMRCs 435 express much higher levels of MMP1 than hESCs, UCMSCs or human foreskin fibroblasts (HFF; Fig. 436 4B). MMP1 could be detected as a highly secreted protein in the conditioned media of IMRCs by ELISA 437 (Fig. 4C ). In addition, the secreted MMP1 was an enzymatically active and correctly processed isoform 438 (Fig. 4D, E) . To investigate the role of the IMRCs on fibrosis, the human epithelial cell line A549 was 439 used to establish an in vitro fibrosis model. The morphology of A549 cells became myofibroblast-like 440 after 48h treatment with 10 ng/mL TGF-β1 (Fig. 4F) . Consistent with the morphological changes, the 441 expression of myofibroblast markers such as ACTA2, Collagen I, Collagen II, Fibronectin and TGFB1 442 increased, while the expression of the epithelial identity marker CDH1 was extinguished, suggesting that 443 the A549 cells had undergone TGF-β1-induced myofibroblast transdifferentiation (Fig. 4G) . 444