Clinical-scale in vitro expansion preserves biological characteristics of cardiac atrial appendage stem cells

• Published in: Cell proliferation Vol. 48; no. 2; pp. 175 - 186
• Main Authors: Windmolders, S., Willems, L., Daniëls, A., Linsen, L., Fanton, Y., Hendrikx, M., Koninckx, R., Rummens, J.-L., Hensen, K.
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.04.2015; John Wiley and Sons Inc
• Subjects: Aged; Atrial Appendage - cytology; Blood Platelets - metabolism; Cell Culture Techniques - methods; Cell Cycle; Cell Differentiation; Cell Proliferation; Cells, Cultured; Female; Humans; Immunophenotyping; Male; Myocardial Infarction - therapy; Original; Regeneration; Stem Cells - cytology; Telomerase - analysis; Telomere Shortening; Ventricular Remodeling - physiology
• ISSN: 0960-7722; 1365-2184
• DOI: 10.1111/cpr.12166

Objectives Cardiac atrial appendage stem cells (CASCs) have recently emerged as an attractive candidate for cardiac regeneration after myocardial infarction. As with other cardiac stem cells, CASCs have to be expanded ex vivo to obtain clinically relevant cell numbers. However, foetal calf serum (FCS), which is routinely used for cell culturing, is unsuitable for clinical purposes, and influence of long‐term in vitro culture on CASC behaviour is unknown. Materials and methods We examined effects on CASC biology of prolonged expansion, and evaluated a culture protocol suitable for human use. Results In FCS‐supplemented medium, CASCs could be kept in culture for 55.75 ± 3.63 days, before reaching senescence. Despite a small reduction in numbers of proliferating CASCs (1.37 ± 0.52% per passage) and signs of progressive telomere shortening (0.04 ± 0.02 kb per passage), their immunophenotype and myocardial differentiation potential remained unaffected during the entire culture period. The cells were successfully expanded in human platelet plasma supernatant, while maintaining their biological properties. Conclusions We successfully developed a protocol for long‐term culture, to obtain clinically relevant CASC numbers, while retaining their cardiogenic potential. These insights in CASC biology and optimization of a humanized platelet‐based culture method are an important step towards clinical application of CASCs for cardiac regenerative medicine.