Lianbo Shao1, Yu Zhang1, Xiangbin Pan2, Bin Liu3, Chun Liang4, Yuqing Zhang1, Yanli Wang1, Bing Yan1, Wenping Xie1, Yi Sun5, Zhenya Shen1, Xi-Yong Yu6, Yangxin Li7. 1. Institute for Cardiovascular Science and Department of Cardiovascular Surgery, First Affiliated Hospital of Soochow University, Suzhou, 215123, Jiangsu, People's Republic of China. 2. Department of Cardiac Surgery, Fuwai Hospital, Beijing, 100037, People's Republic of China. 3. Department of Cardiology, The First Hospital of Jilin University, Changchun, 130041, Jilin, People's Republic of China. 4. Department of Cardiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China. 5. Fuwai Yunnan Cardiovascular Hospital, Kunming, 650302, Yunnan, People's Republic of China. 6. Guangzhou Medical University, Guangzhou, 510080, Guangdong, People's Republic of China. 7. 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.
Abstract
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 β2-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-γ. 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.
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 β2-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-γ. 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.
Authors: Bas Molenaar; Louk T Timmer; Marjolein Droog; Ilaria Perini; Danielle Versteeg; Lieneke Kooijman; Jantine Monshouwer-Kloots; Hesther de Ruiter; Monika M Gladka; Eva van Rooij Journal: Commun Biol Date: 2021-01-29
Authors: Ricardo Cerqueira de Abreu; Hugo Fernandes; Paula A da Costa Martins; Susmita Sahoo; Costanza Emanueli; Lino Ferreira Journal: Nat Rev Cardiol Date: 2020-06-01 Impact factor: 32.419