Cardiac tissue engineering using tissue printing technology and human cardiac progenitor cells.

Tissue engineering is emerging as a potential therapeutic approach to overcome limitations of cell therapy, like cell retention and survival, as well as to mechanically support the ventricular wall and thereby prevent dilation. Tissue printing technology (TP) offers the possibility to deliver, in a defined and organized manner, scaffolding materials and living cells. The aim of our study was to evaluate the combination of TP, human cardiac-derived cardiomyocyte progenitor cells (hCMPCs) and biomaterials to obtain a construct with cardiogenic potential for in vitro use or in vivo application. With this approach, we were able to generate an in vitro tissue with homogenous distribution of cells in the scaffold. Cell viability was determined after printing and showed that 92% and 89% of cells were viable at 1 and 7 days of culturing, respectively. Moreover, we demonstrated that printed hCMPCs retained their commitment for the cardiac lineage. In particular, we showed that 3D culture enhanced gene expression of the early cardiac transcription factors Nkx2.5, Gata-4 and Mef-2c as well as the sarcomeric protein TroponinT. Printed cells were also able to migrate from the alginate matrix and colonize a matrigel layer, thereby forming tubular-like structures. This indicated that printing can be used for defined cell delivery, while retaining functional properties.