Abstract P1113: Patient-derived Cardiac Assembloids Enable Therapeutic Verification Of Regenerative Reagent Bio

Abstract

Background: Preclinical study is a prerequisite for drug developments, and yet animal models are poor predictors in humans. We previously reported GSK3β inhibitor BIO (6-Bromoindirubin-3’-oxime) induced cardiac regeneration in zebrafish and rat models. Methods and Results: For further development of BIO in the models with human features, we generated human pluripotent stem cells (h-iPSCs) to get the cells which are components of heart. H-iPSCs were derived from blood mononuclear cells, or generated from fibroblasts isolated from the heart tissues of recipients after transplantation or from heart samples during autopsy. After confirming the cell markers, h-iPSCs were differentiated into cardiomyocytes (CM), cardiac myofibroblasts (MF), and macrophages (Mac). Decellularized extracellular matrix (dcECM) were extracted from hearts, and we developed spheroids with various combinations. Since CM hardly proliferate and excessive MF is accumulated in damaged heart, cardiac regeneration is challenged by reversal them. Firstly, the effective dosage of BIO was 0.5uM on human cells, while was 5uM on cardiac cells of mice and rats. On BIO treatment with 0.5μM for 3 days, the numbers of total CM and EdU-or Ki67-positive CM were higher in the BIO-treated CM spheroids. Conversely, viability, migration and collagen gel contraction activities of MF were substantially inhibited by BIO treatment. Conclusions: Because tremendous trials for regeneration have failed in clinical applications, it should be validated in realistic study designs with human cells. Here, we successfully reproduced the effects of BIO on human cardiac cells, and suggest the reciprocal regulation of CM and MF by BIO could be attractive therapeutic to heart diseases. More targeted approaches using human cardiac cells and dcECM might allow specific targeting of cardiovascular disease thus optimize regenerative therapy.