Biology subjects

Uhr, D.

Publications and source records attributed to Uhr, D..

3 recordsLinked to original sources

bioRxiv2026

Targeting integrin αvβ3 by chimeric antigen receptor neural stem cell (CAR-NSC) therapy for stroke

Stroke remains a leading cause of adult disability due to the brains limited regenerative capacity. Although stem cell therapies show favorable safety and feasibility profiles in early clinical trials, poor spatial retention and limited engagement with peri-infarct salvageable tissue constrain efficacy. Here, we engineered human induced pluripotent stem cell-derived neural stem cells (NSC) with a chimeric antigen receptor (CAR)-like architecture to enable targeted recognition of injury-associated cues. Specifically, cells were modified to express a membrane-anchored single chain variable fragment (scFv) targeting integrin v{beta}3, a receptor selectively upregulated in peri-infarct vasculature after stroke. Engineered CAR-NSC retained progenitor identity and selectively bound recombinant integrin v{beta}3 in vitro. Following focal transplantation into a photothrombotic stroke mouse model, CAR-NSC displayed broader dispersion within peri-infarct tissue and covered a greater proportion of the ischemic lesion compared to non-binding control-CAR-NSC. CAR-NSC grafts extended longer neurites that aligned more closely with the lesion border. In addition, CAR-NSC transplantation reduced microglial activation and was associated with increased vascular density and blood-brain barrier integrity in the peri-infarct zone. Together, these findings establish a CAR-like NSC strategy for stroke to direct the spatial distribution and tissue engagement of transplanted cells. Molecular targeting of injury-associated cues may improve the precision and regenerative efficacy of cell-based therapies for stroke and related neurological disorders.

neuroscience↗

bioRxiv2024

Human iPSC-derived cell grafts promote functional recovery by molecular interaction with stroke-injured brain

Stroke is a leading cause of disability and death due to the brains limited ability to regenerate damaged neural circuits. To date, stroke patients have only few therapeutic options and are often left with considerable disabilities. Induced pluripotent stem cell (iPSC)-based therapies are emerging as a promising therapeutic approach for stroke recovery. In this study, we demonstrate that local transplantation of iPSC-derived neural progenitor cells (NPCs) improves long-term brain tissue repair responses and reduces neurological deficits after cerebral ischemia in mice. Using in vivo bioluminescence imaging and post-mortem histology, we show long-term graft survival over the course of five weeks and preferential graft differentiation into mature neurons without signs of pluripotent residuals. Transplantation of NPCs led to a set of brain tissue repair responses including increased vascular sprouting and repair, improved blood-brain barrier integrity, reduced microglial activation, and increased neurogenesis compared to littermate control animals receiving sham transplantation. Employing deep learning-assisted behavior analysis, we found that NPC-treated mice displayed improved gait performance and complete fine-motor recovery in the horizontal ladder rung walk, five weeks post-injury. To dissect the molecular graft composition and identify graft-host interactions, single nucleus profiling of the cell transplants and host stroke tissue was performed. We identified graft differentiation preferentially towards neurons with GABAergic and glutamatergic phenotypes in similar proportions, with the remaining cells acquiring astrocyte and NPC-like phenotypes. Interaction between graft and host transcriptome indicated that GABAergic cell grafts were primarily involved in graft-host communication through the regeneration-associated neurexin (NRXN), neuregulin (NRG), neural cell adhesion molecule (NCAM) and SLIT signalling pathways. In conclusion, our study reveals that transplanted iPSC-derived NPCs primarily differentiate into GABAergic neurons contributing to long-term recovery and further delineates the regenerative interactions between the graft and the stroke-injured host tissue.

neuroscience↗

bioRxiv2022

Xeno-free induced pluripotent stem cell-derived neural progenitor cells for in vivo applications

Cell-based therapies are a promising treatment paradigm for neurodegenerative diseases and other brain injuries. Despite recent advances in stem cell technology, major concerns have been raised regarding the feasibility and safety of cell therapies for clinical applications. Here, we generate good manufacturing practice (GMP)-compatible neural progenitor cells (NPCs) from transgene- and xeno-free induced pluripotent stem cells (iPSCs) that can be smoothly adapted for clinical applications. The produced NPCs have a stable gene-expression over at least 15 passages and can be scaled for up to 1018 cells per initially seeded 106 cells. To ensure a pure NPC population for in vivo applications, we reduce risks of iPSC contamination using micro RNA-switch technology as a safety checkpoint. Using lentiviral transduction with a fluorescent and bioluminescent dual-reporter construct, combined with non-invasive in vivo bioluminescent imaging, we longitudinally tracked the grafted cells in healthy wild-type and genetically immunosuppressed mice as well as in a mouse model of ischemic stroke. Long term in-depth characterization revealed that transplanted cells have the capability to survive and spontaneously differentiate into functional and mature neurons throughout a time course of a month.

neuroscience↗