Functionally Competent Cardiac Stem Cells Can Be Isolated From Endomyocardial Biopsies of Patients With Advanced Cardiomyopathies

Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Circulation Research (Impact Factor: 11.02). 02/2011; 108(7):857-61. DOI: 10.1161/CIRCRESAHA.111.241380
Source: PubMed


Two categories of cardiac stem cells (CSCs) with predominantly myogenic (mCSC) and vasculogenic (vCSC) properties have been characterized in the human heart. However, it is unknown whether functionally competent CSCs of both classes are present in the myocardium of patients affected by end-stage cardiac failure, and whether these cells can be harvested from relatively small myocardial samples.
To establish whether a clinically relevant number of mCSCs and vCSCs can be isolated and expanded from endomyocardial biopsies of patients undergoing cardiac transplantation or left ventricular assist device implantation.
Endomyocardial biopsies were collected with a bioptome from the right side of the septum of explanted hearts or the apical LV core at the time of left ventricular assist device implantation. Two to 5 biopsies from each patient were enzymatically dissociated, and, after expansion, cells were sorted for c-kit (mCSCs) or c-kit and KDR (vCSCs) and characterized. mCSCs and vCSCs constituted 97% and 3% of the c-kit population, respectively. Population doubling time averaged 27 hours in mCSCs and vCSCs; 5×10(6) mCSCs and vCSCs were obtained in 28 and 41 days, respectively. Both CSC classes possessed significant growth reserve as documented by high telomerase activity and relatively long telomeres. mCSCs formed mostly cardiomyocytes, and vCSCs endothelial and smooth muscle cells.
The growth properties of mCSCs and vCSCs isolated from endomyocardial biopsies from patients with advanced heart failure were comparable to those obtained previously from larger myocardial samples of patients undergoing elective cardiac surgery.

Download full-text


Available from: Claudia Fiorini,
  • Source
    • "The increased number of c-Kit+ cells in these three pediatric cases may be caused by the inflammation processes occurring in heart’s tissue. Some literature data suggest the existence of two classes of c-Kit+ cells: c-Kit+KDR+ and c-Kit+KDR−, lacking CD105, CD90, CD45, CD133, and CD34 markers [2, 6]. The c-Kit+ cells isolated by us did not show the presence of KDR marker. "
    [Show abstract] [Hide abstract]
    ABSTRACT: According to literature data, self-renewing, multipotent, and clonogenic cardiac c-Kit(+) progenitor cells occur within human myocardium. The aim of this study was to isolate and characterize c-Kit(+) progenitor cells from explanted human hearts. Experimental material was obtained from 19 adult and 7 pediatric patients. Successful isolation and culture was achieved for 95 samples (84.1 %) derived from five different regions of the heart: right and left ventricles, atrium, intraventricular septum, and apex. The average percentage of c-Kit(+) cells, as assessed by FACS, ranged between 0.7 and 0.9 %. In contrast to published data we do not observed statistically significant differences in the number of c-Kit(+) cells between disease-specific groups, parts of the heart or sexes. Nevertheless, c-Kit(+) cells were present in significant numbers (11-24 %) in samples derived from three explanted pediatric hearts. c-Kit(+) cells were also positive for CD105 and a majority of them was positive for CD31 and CD34 (83.7 ± 8.6 and 75.7 ± 11.4 %, respectively). Immunohistochemical analysis of the heart tissue revealed that most cells possessing the c-Kit antigen were also positive for tryptase, a specific mast cell marker. However, flow cytometry analysis has shown cultured c-Kit(+) cells to be negative for hematopoietic marker CD45 and mast cell marker CD33. Isolated c-Kit(+) cells display mesenchymal stem cell features and are thought to differentiate into endothelial cells.
    Clinical Research in Cardiology 04/2014; 103(9). DOI:10.1007/s00392-014-0705-3 · 4.56 Impact Factor
  • Source
    • "On the other hand, it has been suggested that C-kit+ cells in the adult heart are heterogeneous in regard of differentiation potential rather than truly multipotent. When C-kit+ cells were divided based on FLK-1 expression, the FLK-1+ cells showed endothelial differential potential whereas the FLK-1À cells could be induced to cardiac differentiation both in vitro and in vivo [5] [6]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: C-kit expressing cardiac stem cells have been described as multipotent. We have previously identified human cardiac C-kit+CD45- cells, but only found evidence of endothelial commitment. A small cardiac committed subpopulation within the C-kit+CD45- population might however be present. To investigate this at single-cell level, right and left atrial biopsies were dissociated and analyzed by FACS. Only right atrial biopsies contained a clearly distinguishable C-kit+CD45- population, which was single-cell sorted for qPCR. A minor portion of the sorted cells (1.1%) expressed early cardiac gene NKX2.5 while most of the cells (81%) expressed late endothelial gene VWF. VWF- cells were analyzed for a wider panel of genes. One group of these cells expressed endothelial genes (FLK-1, CD31) while another group expressed late cardiac genes (TNNT2, ACTC1). In conclusion, human C-kit+CD45- cells were predominantly localized to the right atrium. While most of these cells expressed endothelial genes, a minor portion expressed cardiac genes.
    Biochemical and Biophysical Research Communications 12/2013; 443(1). DOI:10.1016/j.bbrc.2013.11.086 · 2.30 Impact Factor
  • Source
    • "The human embryonic stem cell line hES-3 was cultured as previously published [54]. Cardiac progenitor cell clones were differentiated both by treatment with 5-azacytidine followed by ascorbic acid and TGF-β to induce cardiomyogenic differentiation [12] and by treatment with 10 nM dexamethasone in DMEM/F12 media supplemented with 10% fetal bovine serum to induce differentiation into all three cardiovascular lineages [13]. Cardiomyogenic differentiation was confirmed by measuring the induction of mature cardiac-specific transcripts by RT-PCR. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Although clinical benefit can be achieved after cardiac transplantation of adult c-kit+ or cardiosphere-derived cells for myocardial repair, these stem cells lack the regenerative capacity unique to neonatal cardiovascular stem cells. Unraveling the molecular basis for this age-related discrepancy in function could potentially transform cardiovascular stem cell transplantation. In this report, clonal populations of human neonatal and adult cardiovascular progenitor cells were isolated and characterized, revealing the existence of a novel subpopulation of endogenous cardiovascular stem cells that persist throughout life and co-express both c-kit and isl1. Epigenetic profiling identified 41 microRNAs whose expression was significantly altered with age in phenotypically-matched clones. These differences were correlated with reduced proliferation and a limited capacity to invade in response to growth factor stimulation, despite high levels of growth factor receptor on progenitors isolated from adults. Further understanding of these differences may provide novel therapeutic targets to enhance cardiovascular regenerative capacity.
    PLoS ONE 10/2013; 8(10):e77464. DOI:10.1371/journal.pone.0077464 · 3.23 Impact Factor
Show more