A Dynamic and Three-Dimensional Human Model of Hypoplastic Left Heart Syndrome to Probe Compromised Cardiomyocyte Proliferation

The proposed study will utilize a 3D-bioprinted heart tube patterned into an endocardial layer (with iPSC-derived endothelial cells) and a myocardial layer (with iPSC-derived cardiomyocytes). The research will interrogate how dysregulated fluid-induced biomechanics and microenvironmental stiffness impede cardiac proliferation in-vitro. The central hypothesis is that aberrant biomechanical forces induce stress-related endocardial-myocardial signaling that ultimately impedes cardiomyocyte proliferation. This will be tested by (1) selectively varying endocardial stiffness within the disease-specific 3D model and assessing intercellular signaling that dysregulates cardiomyocyte proliferation, and (2) applying varying degrees of flow-induced shear stress to the endocardial layer and studying transcriptional shifts at the single-cell level. Successful completion is expected to provide novel etiological insights into HLHS and potential alternative treatment approaches.