New approach methodologies: drug screening platform to identify antifibrotic compounds

Fibrosis is characterized by excessive deposition of extracellular matrix, leading to organ stiffening and progressive dysfunction. Cardiac fibrosis, in particular, is a common feature in ischemic heart failure, genetic cardiomyopathies, diabetes mellitus and aging, which exacerbates cardiac dysfunction and ultimately contributes to increased morbidity and mortality. Despite its clinical burden and importance, there are currently no US Food and Drug Administration-approved drugs that specifically target cardiac fibrosis. This gap is largely due to the lack of reliable translational drug discovery platforms. To address this unmet clinical need, we present our new approach methodology drug screening platform for identifying novel compounds to treat cardiac fibrosis. This high-throughput screening system uses human reporter induced pluripotent stem (iPS) cell-derived cardiac fibroblasts to identify initial hits with potential antifibrotic effects, followed by counter-screening using iPS cell-derived cardiomyocytes to exclude compounds with potential cardiotoxicity. Compared to traditional primary cell-based approaches, our iPS cell-based workflow is robust, scalable and capable of screening ~5,000 compounds within 6–8 weeks. This protocol provides a versatile and efficient platform for phenotypic drug discovery with broad potential for translational applications in medicine.