Posterior heart field and epicardium in cardiac development : PDGFRα and EMT

The processes of heart development, in which a primitive heart tube transforms into a specialized organ with two atria and ventricles divided by septa, are not only important for the understanding of congenital heart defects. These processes also give more insight for the development of heart regeneration therapies. The aim of this thesis was two fold. In the first part, we described the expression pattern of PDGF-A, -C and their receptor PDGFR-_ in the avian heart. Additionally, we studied mouse embryos in which the Pdgfr_ gene was mutated. These data show new insights into the role of PDGFR in a gene regulatory network which supports the development of cardiac structures. The second part of this thesis focused on the process of EMT in human adult EPDC and the role of the EPDC in the differentiation of cardiomyocytes. We gained more insight into the factors involved in EMT of the adult epicardium and showed that EPDCs are indispensible for proper integration of cardiomyocytes into a synchronously beating syncythium. These results might be beneficial for endogenous regulated cell-based cardiac repair.Nederlandse Hartstichting, Jurriaanse Stichting, Lead Pharma Holding BVUBL - phd migration 201