Abstract
Spatiotemporally controlled presentation of morphogens and elaborate modulation of signaling pathways elicit pattern formation during development. Though this process is critical for proper organogenesis, unraveling the mechanisms of developmental biology have been restricted by challenges associated with studying human embryos. Human pluripotent stem cells (hPSCs) have been used to model development in vitro, however difficulties in precise spatiotemporal control of the cellular microenvironment have limited the utility of this model in exploring mechanisms of pattern formation. Here, a simple and versatile method is presented to spatially pattern hPSC differentiation in 2-dimensional culture via localized morphogen adsorption on substrates. Morphogens including bone morphogenetic protein 4 (BMP4), activin A, and WNT3a are patterned to induce localized mesendoderm, endoderm, cardiomyocyte (CM), and epicardial cell (EpiC) differentiation from hPSCs and hPSC-derived progenitors. Patterned CM and EpiC co-differentiation allows investigation of intercellular interactions in a spatially controlled manner and demonstrate improved alignment of CMs in proximity to EpiCs. This approach provides a platform for the controlled and systematic study of early pattern formation. Moreover, this study provides a facile approach to generate 2D patterned hPSC-derived tissue structures for modeling disease and drug interactions.