Abstract P2160: High-throughput Imaging Of Cardiomyocytes Using Biomimetic Tools Help Identify Therapeutic Targets

Abstract

Cardiovascular disease is a leading cause of death and continues to require novel forms of therapies. Mutations in sarcomeres, the basic contractile units of cardiac muscle, causing disarray and loss of function are causal in many genetic cardiomyopathies. Here, we model sarcomeric disarray in vitro by culturing human induced pluripotent stem cell-derived cardiomyocytes (human iPSC-CMs) on tissue culture plates with biomimetic patterned grooves designed to simulate extracellular matrix. This culture system models the natural structure and phenotypic development of human physiology. Next, we created an Adeno-associated virus open reading frame (AAV-ORF) library of ~100 heart failure associated genes of interest (GOI) identified using publicly available human genetic data. We developed a high throughput screening (HTS) process to test the effects of overexpression of these GOIs on sarcomere morphology. Images of human iPSC-CMs treated with overexpression libraries were run through a custom MATLAB HTS image processing script named ‘Tamarack’, developed for quantifying human iPSC-CM sarcomere morphology. Tamarack enables quantification of sarcomere count, length, and orientation. Analysis of sarcomeres from the Tamarack code in the biomimetic plates allows for enhanced quantification of sarcomere structures, in particular, alignment, a metric missing from standard 2D culture plates. We found that treating cells with siRBM20 induced a sarcomere misalignment phenotype which we looked to rescue with overexpression of our GOI. Genes that increased alignment in an RBM20 background were considered top hits and moved to further analysis.