Multi-lineage heart-chip models drug cardiotoxicity and enhances maturation of human stem cell-derived cardiovascular cells.

Cardiovascular toxicity causes adverse drug reactions and may lead to drug removal from the pharmaceutical market. Cancer therapies can induce life-threatening cardiovascular side effects such as arrhythmias, muscle cell death, or vascular dysfunction. New technologies have enabled cardiotoxic compounds to be identified earlier in drug development. Human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs) and vascular endothelial cells (ECs) can screen for drug-induced alterations in cardiovascular cell function and survival. However, most existing hiPSC models for cardiovascular drug toxicity utilize two-dimensional, immature cells grown in static culture. Improved in vitro models to mechanistically interrogate cardiotoxicity would utilize more adult-like, mature hiPSC-derived cells in an integrated system whereby toxic drugs and protective agents can flow between hiPSC-ECs that represent systemic vasculature and hiPSC-CMs that represent heart muscle (myocardium). Such models would be useful for testing the multi-lineage cardiotoxicities of chemotherapeutic drugs such as VEGFR2/PDGFR-inhibiting tyrosine kinase inhibitors (VPTKIs). Here, we develop a multi-lineage, fully-integrated, cardiovascular organ-chip that can enhance hiPSC-EC and hiPSC-CM functional and genetic maturity, model endothelial barrier permeability, and demonstrate long-term functional stability. This microfluidic organ-chip harbors hiPSC-CMs and hiPSC-ECs on separate channels that can be subjected to active fluid flow and rhythmic biomechanical stretch. We demonstrate the utility of this cardiovascular organ-chip as a predictive platform for evaluating multi-lineage VPTKI toxicity. This study may lead to the development of new modalities for the evaluation and prevention of cancer therapy-induced cardiotoxicity.

Protein-encapsulated doxorubicin reduces cardiotoxicity in hiPSC-cardiomyocytes and cardiac spheroids while maintaining anticancer efficacy.

The chemotherapeutic doxorubicin (DOX) detrimentally impacts the heart during cancer treatment. This necessitates development of non-cardiotoxic delivery systems that retain DOX anticancer efficacy. We used human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), endothelial cells (hiPSC-ECs), cardiac fibroblasts (hiPSC-CFs), multi-lineage cardiac spheroids (hiPSC-CSs), patient-specific hiPSCs, and multiple human cancer cell lines to compare the anticancer efficacy and reduced cardiotoxicity of single protein encapsulated DOX (SPEDOX-6), to standard unformulated (UF) DOX. Cell viability assays and immunostaining in human cancer cells, hiPSC-ECs, and hiPSC-CFs revealed robust uptake of SPEDOX-6 and efficacy in killing these proliferative cell types. In contrast, hiPSC-CMs and hiPSC-CSs exhibited substantially lower cytotoxicity during SPEDOX-6 treatment compared with UF DOX. SPEDOX-6-treated hiPSC-CMs and hiPSC-CSs maintained their functionality, as indicated by sarcomere contractility assessment, calcium imaging, multielectrode arrays, and RNA sequencing. This study demonstrates the potential of SPEDOX-6 to alleviate cardiotoxic side effects associated with UF DOX, while maintaining its anticancer potency.

Chemically Defined Production of Tri-Lineage Human iPSC-Derived Cardiac Spheroids.

Cardiac spheroids derived from human induced pluripotent stem cells (hiPSC-cardiac spheroids) represent a powerful three-dimensional (3D) model for examining cardiac physiology and for drug toxicity screening. Recent advances with self-organizing, multicellular cardiac organoids highlight the capability of directed stem cell differentiation approaches to recapitulate the composition of the human heart in vitro. Using hiPSC-derived cardiomyocytes (hiPSC-CMs), hiPSC-derived endothelial cells (hiPSC-ECs), and hiPSC-derived cardiac fibroblasts (hiPSC-CFs) is advantageous for enabling tri-cellular crosstalk within a multilineage system and for generating patient-specific models. Chemically defined medium containing factors needed to simultaneously maintain hiPSC-CMs, hiPSC-ECs, and hiPSC-CFs is used to produce the spheroid system. In this article, we present protocols to illustrate the methods for conducting small-molecule-mediated differentiations of hiPSCs into cardiomyocytes, endothelial cells, and cardiac fibroblasts, as well as to assemble the fully integrated cardiac spheroids. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Maintenance and expansion of hiPSCs Basic Protocol 2: Differentiation of hiPSCs into cardiomyocytes Basic Protocol 3: Differentiation of hiPSCs into vascular endothelial cells Basic Protocol 4: Differentiation of hiPSCs into cardiac fibroblasts Basic Protocol 5: Production of hiPSC-derived cardiac spheroids.