Search for: All records

Cardiac fibrosis is a pathological hallmark of almost all forms of heart disease, characterized by excessive deposition of extracellular matrix (ECM) proteins by activated fibroblasts, leading to cardiomyocyte hypertrophy, arrhythmias, and heart failure. Current treatments, predominantly pharmacological, target signaling pathways involved in fibroblast activation but often come with side effects such as cardiac toxicities. There is a critical need for therapies that specifically target activated cardiac fibroblasts to mitigate these adverse effects. Recent advances have shown that chimeric antigen receptor (CAR)-T cells targeting fibroblast activation protein (FAP), expressed by activated fibroblasts, can significantly reduce fibrosis and improve cardiac function in mouse models. However, CAR-T cell therapies face challenges such as the requirement for large quantities of healthy primary immune cells, lengthy process, and the high cost of personalized treatments. To address these issues, we propose an innovative strategy using off-the-shelf CAR-neutrophils derived from human pluripotent stem cells (hPSCs). We hypothesize that hPSC-derived CAR-neutrophils engineered to target FAP will effectively reduce cardiac fibrosis and improve cardiac function post-injury due to their potent cytotoxic effects and ability to infiltrate infarct regions. To test this hypothesis, anti-FAP CAR hPSCs were generated by CRISPR/Cas9 genome editing and differentiated into neutrophils. The differentiated anti-FAP CAR hPSC-neutrophils exhibited molecular characteristics comparable to unmodified hPSC-neutrophils. We also established an in vitro cardiac fibrosis model utilizing a previously reported protocol for the generation of hPSC-derived epicardial fibroblasts. Importantly, our anti-FAP hPSC-neutrophils exhibited significant cytotoxicity against activated epicardial fibroblasts, while unmodified hPSC-neutrophils showed no/minimal killing efficiency. This study suggests a proof-of-concept therapeutic approach against cardiac fibrosis utilizing FAP-targeting CAR-neutrophils. This strategy can potentially be adapted to treat fibrosis in other organs, thereby having a broad and significant impact on the treatment of various fibrotic diseases, ultimately contributing to longer, healthier human lives. 

Abstract Extracellular vesicles (EVs) secreted by human brain cells have great potential as cell‐free therapies in various diseases, including stroke. However, because of the significant amount of EVs needed in preclinical and clinical trials, EV application is still challenging. Vertical‐Wheel Bioreactors (VWBRs) have designed features that allow for scaling up the generation of human forebrain spheroid EVs under low shear stress. In this study, EV secretion by human forebrain spheroids derived from induced pluripotent stem cells as 3D aggregates and on Synthemax II microcarriers in VWBRs were investigated with static aggregate culture as a control. The spheroids were characterized by metabolite and transcriptome analysis. The isolated EVs were characterized by nanoparticle tracking analysis, electron microscopy, and Western blot. The EV cargo was analyzed using proteomics and miRNA sequencing. The in vitro functional assays of an oxygen and glucose‐deprived stroke model were conducted. Proof of concept in vivo study was performed, too. Human forebrain spheroid differentiated on microcarriers showed a higher growth rate than 3D aggregates. Microcarrier culture had lower glucose consumption per million cells and lower glycolysis gene expression but higher EV biogenesis genes. EVs from the three culture conditions showed no differences in size, but the yields from high to low were microcarrier cultures, dynamic aggregates, and static aggregates. The cargo is enriched with proteins (proteomics) and miRNAs (miRNA‐seq), promoting axon guidance, reducing apoptosis, scavenging reactive oxygen species, and regulating immune responses. Human forebrain spheroid EVs demonstrated the ability to improve recovery in an in vitro stroke model and in vivo. Human forebrain spheroid differentiation in VWBR significantly increased the EV yields (up to 240–750 fold) and EV biogenesis compared to static differentiation due to the dynamic microenvironment and metabolism change. The biomanufactured EVs from VWBRs have exosomal characteristics and more therapeutic cargo and are functional in in vitro assays, which paves the way for future in vivo stroke studies. 

The past decade has witnessed significant advances in cancer immunotherapy, particularly through the adoptive transfer of engineered T cells in treating advanced leukemias and lymphomas. Despite these excitements, challenges remain with scale, cost, and ensuring quality control of engineered immune cells, including chimeric antigen receptor T, natural killer cells, and macrophages. The advent of human pluripotent stem cells (hPSCs), including human embryonic stem cells and induced pluripotent stem cells, has transformed immunotherapy by providing a scalable, off-the-shelf source of any desired immune cells for basic research, translational studies, and clinical interventions. The tractability of hPSCs for gene editing could also generate homogenous, universal cellular products with custom functionality for individual or combinatory therapeutic applications. This review will explore various immune cell types whose directed differentiation from hPSCs has been achieved and recently adapted for translational immunotherapy and feature forward-looking bioengineering techniques shaping the future of the stem cell field. 

Immunotherapy is a powerful technique where immune cells are modified to improve cytotoxicity against cancerous cells to treat cancers that do not respond to surgery, chemotherapy, or radiotherapy. Expressing chimeric antigen receptor (CAR) in immune cells, typically T lymphocytes, is a practical modification that drives an immune response against cancerous tissue. CAR-T efficacy is suboptimal in solid tumors due to the tumor microenvironment (TME) that limits T lymphocyte cytotoxicity. In this study, we demonstrate that neutrophils differentiated from human pluripotent stem cells modified with AAVS1-inserted CAR constructs showed a robust cytotoxic effect against prostate-specific membrane antigen (PSMA) expressing LNCaP cells as a model for prostate cancer in vitro. Our results suggest that engineered CAR can significantly enhance the neutrophil anti-tumor effect, providing a new avenue in treating prostate cancers.