technical-applications-microelectrode-array-patch-clamp-recordings-on

Technical Applications of Microelectrode Array and Patch Clamp Recordings on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Drug-induced cardiotoxicity is the leading cause of drug attrition and withdrawal from the market. Therefore, using appropriate preclinical cardiac safety ...

Stanford University School of Medicine

Activated fibroblasts are the major cell type that secretes excessive extracellular matrix in response to injury, contributing to pathological fibrosis and leading to organ failure. Effective anti-fibrotic therapeutic solutions, however, are not available due to the poorly defined characteristics and unavailability of tissue-specific fibroblasts. Recent advances in single-cell RNA-sequencing fill such gaps of knowledge by enabling delineation of the developmental trajectories and identification of regulatory pathways of tissue-specific fibroblasts among different organs.

Generation of Quiescent Cardiac Fibroblasts From Human Induced Pluripotent Stem Cells for In Vitro Modeling of Cardiac Fibrosis.

Aortic aneurysm is an asymptomatic disease with dire outcomes if undiagnosed. Aortic aneurysm rupture is a significant cause of death worldwide. To date, surgical repair or endovascular repair (EVAR) is the only effective treatment for aortic aneurysm, as no pharmacological treatment has been found effective. Aortic aneurysm, a focal dilation of the aorta, can be formed in the thoracic (TAA) or the abdominal (AAA) region; however, our understanding as to what determines the site of aneurysm formation remains quite limited. The extracellular matrix (ECM) is the noncellular component of the aortic wall, that in addition to providing structural support, regulates bioavailability of an array of growth factors and cytokines, thereby influencing cell function and behavior that ultimately determine physiological or pathological remodeling of the aortic wall. Here, we provide an overview of the ECM proteins that have been reported to be involved in aortic aneurysm formation in humans or animal models, and the experimental models for TAA and AAA and the link to ECM manipulations. We also provide a comparative analysis, where data available, between TAA and AAA, and how aberrant ECM proteolysis versus disrupted synthesis may determine the site of aneurysm formation.

Extracellular matrix, regional heterogeneity of the aorta, and aortic aneurysm.

Myocardial fibrosis is a hallmark of cardiac remodeling, which can progressively lead to heart failure, a leading cause of death worldwide. The effector cells of fibrosis in the heart are cardiac fibroblasts (CFs). There is currently no effective therapeutic strategy clinically available to specifically attenuate maladaptive responses of CFs. Large-scale applications such as high-throughput drug screening are difficult due to the limited availability of human primary CFs, thus limiting the development of future treatments. Here, we describe a robust induction protocol that can be used to generate a scalable, consistent, genetically defined source of quiescent CFs from human induced pluripotent stem cells for cardiac fibrosis modeling, drug discovery, and tissue engineering.

Generation of Quiescent Cardiac Fibroblasts Derived from Human Induced Pluripotent Stem Cells.

The developmental origin of vascular smooth muscle cells (VSMCs) has been increasingly recognized as a major determinant for regional susceptibility or resistance to vascular diseases. As a human material-based complement to animal models and human primary cultures, patient induced pluripotent stem cell iPSC-derived VSMCs have been leveraged to conduct basic research and develop therapeutic applications in vascular diseases. However, iPSC-VSMCs (induced pluripotent stem cell VSMCs) derived by most existing induction protocols are heterogeneous in developmental origins. In this review, we summarize signaling networks that govern in vivo cell fate decisions and in vitro derivation of distinct VSMC progenitors, as well as key regulators that terminally specify lineage-specific VSMCs. We then highlight the significance of leveraging patient-derived iPSC-VSMCs for vascular disease modeling, drug discovery, and vascular tissue engineering and discuss several obstacles that need to be circumvented to fully unleash the potential of induced pluripotent stem cells for precision vascular medicine.

Generation of Vascular Smooth Muscle Cells From Induced Pluripotent Stem Cells: Methods, Applications, and Considerations.

Hypertrophic cardiomyopathy (HCM) is a common inherited heart disease with a prevalence of about 0.2%. HCM is typically caused by mutations in genes encoding sarcomere or sarcomere-associated proteins. Here, we characterized induced pluripotent stem cell (iPSC) lines generated from the peripheral blood mononuclear cells of three HCM patients each carrying c.433C > T, c.610C > T, or c.235C > T mutation in the TNNI3 gene by non-integrated Sendai virus. All of the three lines exhibited normal morphology, expression of pluripotent markers, stable karyotype, and the potential of trilineage differentiation. The cardiomyocytes differentiated from these iPSC lines can serve as useful tools to model HCM in vitro.

Generation of three induced pluripotent stem cell lines from hypertrophic cardiomyopathy patients carrying TNNI3 mutations.

Vascular smooth muscle cells (VSMCs), a highly mosaic tissue, arise from multiple distinct embryonic origins and populate different regions of our vascular network with defined boundaries. Accumulating evidence has revealed that the heterogeneity of VSMC origins contributes to region-specific vascular diseases such as atherosclerosis and aortic aneurysm. These findings highlight the necessity of taking into account lineage-dependent responses of VSMCs to common vascular risk factors when studying vascular diseases. This chapter describes a reproducible, stepwise protocol for the generation of isogenic VSMC subtypes originated from proepicardium, second heart field, cardiac neural crest, and ventral somite using human induced pluripotent stem cells. By leveraging this robust induction protocol, patient-derived VSMC subtypes of desired embryonic origins can be generated for disease modeling as well as drug screening and development for vasculopathies with regional susceptibility.

Mengcheng Shen

Stanford Cardiovascular Institute,
Division of Cardiovascular Medicine,
Department of Medicine,
Division of Cardiovascular Medicine, Department of Medicine

Stanford University School of Medicine

Technical Applications of Microelectrode Array and Patch Clamp Recordings on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Mengcheng Shen

Stanford Cardiovascular Institute,Division of Cardiovascular Medicine,Department of Medicine,Division of Cardiovascular Medicine, Department of Medicine

Stanford University School of Medicine

Technical Applications of Microelectrode Array and Patch Clamp Recordings on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Stanford Cardiovascular Institute,
Division of Cardiovascular Medicine,
Department of Medicine,
Division of Cardiovascular Medicine, Department of Medicine