The “Natural Selection” of Muscle for Cardiac Repair by Paul Riley Circulation Research Volume 106(1):4-6 January 8, 2010 Copyright © American Heart Association, Inc. All rights reserved.

Figure. Enrichment of ESC-derived cardiomyocytes. Figure. Enrichment of ESC-derived cardiomyocytes. Traditionally, cardiac progenitors are selected and enriched from heterogeneous ESC cultures based on either transgenic (mouse; mESCs) or (lenti-)viral (human; hESCs) introduction of reporter cassettes under the control of cardiac-specific promoters (Nkx2.5 or αMHC), followed by flow cytometry and selectable drug resistance. The end result is a population of genetically modified cardiomyocytes (A). The identification of specific cell surface markers, Prp in combination with PDGFRα, concomitant with ESC cardiac specification, enables selection of unmodified, “natural” cardiomyocytes (PRa+) as a more optimal approach, both for the study of cardiac differentiation and extrapolation toward cell transplantation therapy (B). Paul Riley Circ Res. 2010;106:4-6 Copyright © American Heart Association, Inc. All rights reserved.