title: Co-culture with cardiomyocytes enhanced the myogenic conversion of mesenchymal stromal cells in a dose-dependent manner.
abstract: To increase the accessibility of myogenic cells for cell therapy in the infarcted heart, we identified conditions to improve the reproducible conversion of bone marrow mesenchymal stromal cells (BMSCs) into myogenic cells. Such cells may permit functional regeneration following a myocardial infarction. BMSCs derived from green fluorescent protein (GFP) transgenic rats were co-cultured with neonatal rat cardiomyocytes (1:1, 1:10, 1:20, and 1:40 ratios) for 7 days. Some BMSCs contracted synchronously with the neonatal cardiomyocytes, and exhibited action potentials that were confirmed with current clamp recordings. The myogenic phenotype of the BMSCs was confirmed by immunohistochemical staining and flow cytometry (antibodies against cardiac specific alpha-sarcomeric actinin, Troponin I, MEF-2C). An increase in the number of BMSCs expressing cardiac markers correlated with increasing numbers of neonatal cardiomyocytes in the culture. When BMSCs were co-cultured with DiI-labeled neonatal cardiomyocytes, a small percentage of GFP/DiI/Troponin I triple-positive cells were observed after 7 days. This type of myogenic conversion increased nearly twofold when BMSCs were co-cultured with apoptotic (TNF-alpha-treated) cardiomyocytes. BMSCs co-cultured with cardiomyocytes acquired a functional myogenic phenotype in a dose-dependent manner. Myogenic conversion increased when the BMSCs were cultured with apoptotic cells.
authors.affiliation: Division of Cardiovascular Surgery and Department of Surgery, Toronto General Research Institute and University of Toronto, Toronto, ON, Canada.
authors.forename: Xiao-Qing
authors.initials: XQ
authors.lastname: He
authors.forename: Min-Sheng
authors.initials: MS
authors.lastname: Chen
authors.forename: Shu-Hong
authors.initials: SH
authors.lastname: Li
authors.forename: Shi-Ming
authors.initials: SM
authors.lastname: Liu
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhong
authors.forename: Heather Y
authors.initials: HY
authors.lastname: McDonald Kinkaid
authors.forename: Wei-Yang
authors.initials: WY
authors.lastname: Lu
authors.forename: Richard D
authors.initials: RD
authors.lastname: Weisel
authors.forename: Ren-Ke
authors.initials: RK
authors.lastname: Li
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D000831:Animals, Newborn; D017209:Apoptosis; D001854:Bone Marrow Cells / Q000378:metabolism*; D002454:Cell Differentiation; D002459:Cell Fusion; D002478:Cells, Cultured; D004594:Electrophysiology; D007124:Immunoenzyme Techniques; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D032383:Myocytes, Cardiac / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D017154:Stromal Cells / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D014409:Tumor Necrosis Factor-alpha