| Description |
The purpose of this investigation was to determine the effect of decellularized extracellular porcine heart matrix (ECM) on the transcriptional and structural properties of cardiac cells in culture. This was motivated by the need of having a physiologically relevant cardiac model for understanding and treating cardiac diseases. We also sought to address two major aims of cardiac in vitro models, namely, improving individual cell morphology, and fiber-like formation of plated cells. To this end, cardiomyocytes (CMs) and fibroblasts from induced Pluripotent Stem (iPS) cells were plated at a progenitor and differentiated state onto an ECM. These cells would dive into the ECM upon plating and would therefore develop within it. The cells plated cultured within the ECM were compared against a monolayer control condition grown on vitronectin-coated plates. The structural differences between all three conditions was carried out using confocal microscopy. The monolayer condition was shown to have random structure of CMs with fibroblasts sporadically dispersed throughout the sample. Progenitor plated cells at Day-30 revealed CMs that formed fiber-like structures with specific directionality and interweaved with fibroblasts throughout. Differentiated plated cells at Day-30 showed three-dimensional structure of CMs, with a general directionality, however this did not show directed growth, nor close interaction with fibroblasts. Further comparison was performed between the monolayer plated condition and the progenitor plated ECM condition through use of single-cell RNA sequencing. Upregulated gene pathways of CMs plated on the ECM contrasted with those from the monolayer condition were related to cardiac structure and contraction. Fibroblasts cultured within the ECM showed upregulation of genes related to sustaining CM function when compared to fibroblasts from the monolayer control, thereby coinciding with one of their main purposes within the heart. Through these modes of analysis, it is evident that progenitor plated cells on ECM produce superior results than the other culturing conditions. The fiber-like structures of CMs and upregulation of pathways related to native CM and fibroblast function in the heart allow for an improved cardiac model that can be used to study and treat diseases. |
