title: Genetic lineage tracing identifies in situ Kit-expressing cardiomyocytes.
abstract: Cardiac cells marked by c-Kit or Kit, dubbed cardiac stem cells (CSCs), are in clinical trials to investigate their ability to stimulate cardiac regeneration and repair. These studies were initially motivated by the purported cardiogenic activity of these cells. Recent lineage tracing studies using Kit promoter to drive expression of the inducible Cre recombinase showed that these CSCs had highly limited cardiogenic activity, inadequate to support efficient cardiac repair. Here we reassess the lineage tracing data by investigating the identity of cells immediately after Cre labeling. Our instant lineage tracing approach identifies Kit-expressing cardiomyocytes, which are labeled immediately after tamoxifen induction. In combination with long-term lineage tracing experiments, these data reveal that the large majority of long-term labeled cardiomyocytes are pre-existing Kit-expressing cardiomyocytes rather than cardiomyocytes formed de novo from CSCs. This study presents a new interpretation for the contribution of Kit(+) cells to cardiomyocytes and shows that Kit genetic lineage tracing over-estimates the cardiogenic activity of Kit(+) CSCs.
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Qiaozhen
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Yang
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Xiuzhen
authors.initials: X
authors.lastname: Huang
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Lingjuan
authors.initials: L
authors.lastname: He
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Libo
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Xueying
authors.initials: X
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Nie
authors.affiliation: State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
authors.forename: Shengshou
authors.initials: S
authors.lastname: Hu
authors.affiliation: Zhongshan Hospital, Fudan University, Shanghai 200032, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, Zhejiang 310003, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Cardiovascular Medicine, Southern Medical University Affiliated Fengxian Hospital, Shanghai 201499, China.
authors.forename: Zengyong
authors.initials: Z
authors.lastname: Qiao
authors.affiliation: Cardiovascular and Metabolic Diseases Innovative Medicines, AstraZeneca, Mölndal 43183, Sweden.
authors.forename: Qing-Dong
authors.initials: QD
authors.lastname: Wang
authors.affiliation: Department of Chemical Pathology, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR 999077, China.
authors.forename: Kathy O
authors.initials: KO
authors.lastname: Lui
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.|Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.|ShanghaiTech University, Shanghai 201210, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
mesh_terms: D000818:Animals; D019070:Cell Lineage; D002478:Cells, Cultured; D015870:Gene Expression; D006321:Heart / Q000502:physiology*; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000166:cytology; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis* / Q000235:genetics; D012038:Regeneration; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism
chemical_list: D019009:Proto-Oncogene Proteins c-kit