Concurrent Isolation of Three Distinct Cardiac Stem Cell Populations from a Single Human Heart Biopsy
Rationale: The relative actions and synergism between distinct myocardial-derived stem cell populations remains obscure. Ongoing debates regarding optimal cell population(s) for treatment of heart failure prompted implementation of a protocol for isolation of multiple stem cell populations from a single myocardial tissue sample to develop new insights for achieving myocardial regeneration.
Objective: Establish a robust cardiac stem cell isolation and culture protocol to consistently generate three distinct stem cell populations from a single human heart biopsy.
Methods and Results: Isolation of three endogenous cardiac stem cell populations was performed from human heart samples routinely discarded during implantation of a left ventricular assist device (LVAD). Tissue explants were mechanically minced into 1 mm3 pieces to minimize time exposure to collagenase digestion and preserve cell viability. Centrifugation removes large cardiomyocytes (CMs) and tissue debris producing a single cell suspension that is sorted using magnetic-activated cell sorting (MACS) technology. Initial sorting is based upon c-Kit expression that enriches for two c-kit+ cell populations yielding a mixture of cardiac progenitor cells (CPCs) and endothelial progenitor cells (EPCs). Flow through c-Kit- mesenchymal stem cells (MSCs) are positively selected by surface expression of markers CD90 and CD105. After one week of culture the c-Kit+ population is further enriched by selection for a CD133+ EPC population. Persistence of respective cell surface markers in vitro is confirmed both by flow cytometry and immunocytochemistry.
Conclusions: Three distinct cardiac cell populations with individualized phenotypic properties consistent with CPCs, EPCs and MSCs can be successfully concurrently isolated and expanded from a single tissue sample derived from human heart failure patients.
- Received December 16, 2016.
- Revision received April 19, 2017.
- Accepted April 25, 2017.