PMID- 31312880 OWN - NLM STAT- MEDLINE DCOM- 20200318 LR - 20200318 IS - 1420-9071 (Electronic) IS - 1420-682X (Linking) VI - 77 IP - 5 DP - 2020 Mar TI - Knockout of beta-2 microglobulin enhances cardiac repair by modulating exosome imprinting and inhibiting stem cell-induced immune rejection. PG - 937-952 LID - 10.1007/s00018-019-03220-3 [doi] AB - BACKGROUND AND AIMS: Allogeneic human umbilical mesenchymal stem cells (alloUMSC) are convenient cell source for stem cell-based therapy. However, immune rejection is a major obstacle for clinical application of alloUMSC for cardiac repair after myocardial infarction (MI). The immune rejection is due to the presence of human leukocyte antigen (HLA) class I molecule which is increased during MI. The aim of this study was to knockout HLA light chain beta(2)-microglobulin (B2M) in UMSC to enhance stem cell engraftment and survival after transplantation. METHODS AND RESULTS: We developed an innovative strategy using CRISPR/Cas9 to generate UMSC with B2M deletion (B2M(-)UMSC). AlloUMSC injection induced CD8(+) T cell-mediated immune rejection in immune competent rats, whereas no CD8(+) T cell-mediated killing against B2M(-)UMSC was observed even when the cells were treated with IFN-gamma. Moreover, we demonstrate that UMSC-derived exosomes can inhibit cardiac fibrosis and restore cardiac function, and exosomes derived from B2M(-)UMSC are more efficient than those derived from UMSC, indicating that the beneficial effect of exosomes can be enhanced by modulating exosome's imprinting. Mechanistically, microRNA sequencing identifies miR-24 as a major component of the exosomes from B2M(-)UMSCs. Bioinformatics analysis identifies Bim as a putative target of miR-24. Loss-of-function studies at the cellular level and gain-of-function approaches in exosomes show that the beneficial effects of B2M(-)UMSCs are mediated by the exosome/miR-24/Bim pathway. CONCLUSION: Our findings demonstrate that modulation of exosome's imprinting via B2M knockout is an efficient strategy to prevent the immune rejection of alloUMSCs. This study paved the way to the development of new strategies for tissue repair and regeneration without the need for HLA matching. FAU - Shao, Lianbo AU - Shao L AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Zhang, Yu AU - Zhang Y AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Pan, Xiangbin AU - Pan X AD - Department of Cardiac Surgery, Fuwai Hospital, Beijing, 100037, People's Republic of China. FAU - Liu, Bin AU - Liu B AD - Department of Cardiology, The First Hospital of Jilin University, Changchun, 130041, Jilin, People's Republic of China. FAU - Liang, Chun AU - Liang C AD - Department of Cardiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China. FAU - Zhang, Yuqing AU - Zhang Y AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Wang, Yanli AU - Wang Y AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Yan, Bing AU - Yan B AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Xie, Wenping AU - Xie W AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Sun, Yi AU - Sun Y AD - Fuwai Yunnan Cardiovascular Hospital, Kunming, 650302, Yunnan, People's Republic of China. FAU - Shen, Zhenya AU - Shen Z AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. FAU - Yu, Xi-Yong AU - Yu XY AD - Guangzhou Medical University, Guangzhou, 510080, Guangdong, People's Republic of China. FAU - Li, Yangxin AU - Li Y AUID- ORCID: 0000-0002-2364-3207 AD - Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. yangxin_li@yahoo.com. LA - eng PT - Journal Article DEP - 20190716 PL - Switzerland TA - Cell Mol Life Sci JT - Cellular and molecular life sciences : CMLS JID - 9705402 RN - 0 (Bcl-2-Like Protein 11) RN - 0 (IFNG protein, human) RN - 0 (MIRN24 microRNA, human) RN - 0 (MicroRNAs) RN - 0 (beta 2-Microglobulin) RN - 82115-62-6 (Interferon-gamma) SB - IM MH - Animals MH - Bcl-2-Like Protein 11/metabolism MH - CD8-Positive T-Lymphocytes/immunology MH - CRISPR-Cas Systems/*genetics MH - Cells, Cultured MH - Exosomes/metabolism MH - Fibrosis/prevention & control MH - Human Umbilical Vein Endothelial Cells/cytology/transplantation MH - Humans MH - Interferon-gamma/pharmacology MH - Mesenchymal Stem Cell Transplantation/*methods MH - Mesenchymal Stem Cells/cytology/*immunology MH - MicroRNAs/genetics MH - Myocardial Infarction/*therapy MH - Rats MH - beta 2-Microglobulin/*genetics/metabolism OTO - NOTNLM OT - Cytotoxicity OT - Exosomal miRNA OT - Exosome OT - Exosome's imprinting OT - Myocardial infarction EDAT- 2019/07/18 06:00 MHDA- 2020/03/19 06:00 CRDT- 2019/07/18 06:00 PHST- 2019/01/30 00:00 [received] PHST- 2019/07/05 00:00 [accepted] PHST- 2019/06/26 00:00 [revised] PHST- 2019/07/18 06:00 [pubmed] PHST- 2020/03/19 06:00 [medline] PHST- 2019/07/18 06:00 [entrez] AID - 10.1007/s00018-019-03220-3 [pii] AID - 10.1007/s00018-019-03220-3 [doi] PST - ppublish SO - Cell Mol Life Sci. 2020 Mar;77(5):937-952. doi: 10.1007/s00018-019-03220-3. Epub 2019 Jul 16.