Year 3

Overall, we have been able to complete the milestones proposed for our grant. We have generated a unique panel of control and ARVC hiPSC lines using integration-free methods. We provide evidence of our method to generate robust numbers of hiPSC derived cardiac cells that express key components of the cardiac muscle cell-cell junction include mechanical junctions and electrical junctions. We show that our ARVC hiPSC lines display disease symptom-specific features (adipogenic and arrhythmic), which phenocopy the striking and differential diagnosis observed in our ARVC donor hearts and provide a platform to study the varying disease features underlying ARVC. We uncover novel and classic molecular and ultrastructural defects underlying the arrhythmogenic defects in our ARVC hiPSC lines that mimic the gradation in disease severity observed in ARVC donor hearts. We exploit conventional ARVC drugs to determine their impact on arrhythmogenic behavior and reversibility of phenotypes in our cells. We have published 4 articles in the field of cell-cell junction remodeling, protein turnover and stem cell approaches that further our understanding of this field in cardiac muscle cells as well as filed a provisional patent application on the use of a novel drug discovery system for fat arrhythmogenic disorders that exploit the genetic diversity and clinical features observed in our ARVC lines.