Suicide Gene-Mediated Sequencing Ablation Revealed the Potential Therapeutic Mechanism of Induced Pluripotent Stem Cell-Derived Cardiovascular Cell Patch Post-Myocardial Infarction

Abstract

Aims: This study is designed to assess the protective cardiac effects after myocardial infarction (MI) of (i) cardiovascular progenitor cells (PC) differentiated directly into cardiomyocytes (CM) and endothelial cells (ECs) at the injury site, as separable from the effects of (ii) paracrine factors released from PC. Results: In vivo: bi-cell patch containing induced pluripotent stem cell (iPSC)-derived CM and EC (BIC) was transplanted onto the infarcted heart. BIC were transduced with herpes simplex virus thymidine kinase ''suicide'' gene driven by cardiac NCX1 or endothelial vascular endothelium-cadherin promoter. IGF-1a and VEGF levels released from ischemic tissues were significantly enhanced in the BIC patch treatment group. Heart function, infarction size, and vessel density were significantly improved after BIC patch treatment. These effects were completely abolished in the group given ganciclovir (GCV) at week 1 as a suicide gene activator, and partially abolished in the group given GCV at week 3 as compared with the untreated cell patch group. Innovation: This study was designed to distinguish between cell-based and noncell-based therapeutic effects of PC lineages after MI. PCs derived from iPSC were genetically modified to express ''suicide'' gene. iPSC-derived CM and EC were then ablated in situ at week 1 and 3 by intraperitoneal administration of GCV. This enabled direct assessment of the effects of iPSC transplantation on myocardial function and tissue regeneration potential. Conclusions: Data support a mechanism in which iPSC-derived cardiovascular lineages contribute directly to improved cardiac performance and attenuated remodeling. Paracrine factors provide additional support to the restoration of heart function. Antioxid. Redox Signal. 21, 2177-2191.

Electrical Stimulation Enhances Cardiac Differentiation of Human Induced Pluripotent Stem Cells for Myocardial Infarction Therapy

“…In addition, cell engraftment can minimize the adverse scar growth, ultimately reducing adverse remodeling (23,25,43). Although other effects such as angiogenesis or antiapoptosis (by paracrine factors) cannot be excluded, our previous studies have demonstrated cell engraftment of implanted CMs as the primary contributor to the cardiac functional restoration by using a specific cell suicide approach (61). Thus, EleS appears as an important preconditioning approach for CM generation from hiPSCs in the design of cell-based therapies for infarcted heart.…”

“…The cell maintenance and differentiation approaches were performed according to the manufacturer's instructions. The differentiation protocol of hiPSCs through EB formation was modified according to our previous report (61). Briefly, hiPSCs were maintained in Essential 8Ô culture medium on culture dishes coated with vitronectin (0.5 lg/cm 2 ) at 37°C in a humid atmosphere of 5% CO 2 and expanded for 3-4 days.…”

“…Total RNA was isolated from various treatment groups of cells using the RNeasy Mini kit (Qiagen), and cDNA was prepared using the Omniscript-RT kit (Qiagen). Each PCR was performed with specific primers, and the QuantiTect SYBR green PCR kit (Qiagen) was used with BIO-RAD-iQ5 optical module as previously described (61). The mRNA level was standardized to internal control (GAPDH) and expressed as fold changes.…”

“…As previously described (61), single-cell suspensions of differentiated iPSCs were trypsinized 20 days after differentiation. About 10 6 cells were fixed on ice with 4% paraformaldehyde for 30 min and permeabilized in 0.1% saponin for 30 min, followed by 1% FBS on ice for 30 min.…”

Circulating IgGs in Type 2 Diabetes with Atrial Fibrillation Induce IP3-Mediated Calcium Elevation in Cardiomyocytes

“…To test whether IgG autoantibodies purified from patients with T2DM with AF (T2DM/AF) (Table 1) could alter intracellular calcium homeostasis in cardiomyocytes, human induced pluripotent stem cells (iPSCs) were differentiated into cardiomyocytes (Wang et al, 2014). These cells were loaded with fluorescent calcium indicator Fura-2-acetoxymethyl ester (Fura-2, AM) and intracellular calcium level (presented as F 350nm /F 385nm ) was monitored using live cell imaging.…”