Biology subjects

Gottschalk, S.

Publications and source records attributed to Gottschalk, S..

7 recordsLinked to original sources

bioRxiv2026

Reprogramming CAR T-Cells with designed bioPROTACs

Gene editing has been used to enhance CAR T-cell function by disrupting negative regulators but has limitations. Here we show that de novo-designed generated targeted degraders (bioPROTACs) provide an alternative approach. Expression of bioPROTACs in CAR T-cells targeting DNMT3A, a key regulator of T-cell exhaustion, phenocopied gene knockout. Our reversible, non-gene editing approach provides a tunable strategy to reprogram T-cell fate which should be broadly applicable for next-generation cell therapies.

immunology↗

bioRxiv2026

Mining single-cell transcriptomic data reveals distinct T-cell population in pediatric B-ALL and AML at diagnosis

Immunotherapy represents a promising strategy to improve outcomes in pediatric leukemia; however, its efficacy remains considerably lower in acute myeloid leukemia (AML) compared with B-cell acute lymphoblastic leukemia (B-ALL). To characterize T-cell subsets in AML and B-ALL at diagnosis, we took advantage of existing data sets and performed an integrated single-cell RNA sequencing (scRNA-seq) analysis of T cells present in the bone marrow of pediatric patients with B-ALL (n=89) and AML (n=26), and healthy donors (n=9). In total, 47,610 T cells were analyzed, revealing 17 transcriptionally distinct subsets. Comparative analysis identified T-cell subsets distinguishing B-ALL from AML, such as proliferative, naive CD4, and progenitor exhausted, and naive or resting CD4 regulatory T cells. We identified a rare T-cell subset expressing hemoglobin genes, which was enriched in B-ALL and characterized by upregulation of heme metabolism and chronic hypoxia-associated pathways, and its abundance was associated with better outcomes. Collectively, our findings delineate the transcriptional and functional heterogeneity of T cells in pediatric B-ALL and AML and provide insights that may inform future T-cell-based immunotherapeutic strategies.

immunology↗

bioRxiv2025

Targeting Regnase-1 unleashes CAR T cell antitumor activity for osteosarcoma and creates a proinflammatory tumor microenvironment

Negative regulators of T cell function represent promising targets to enhance the intrinsic antitumor activity of CAR T cells against solid tumors. However, the endogenous immune ecosystem in solid tumors often represents an immunosuppressive therapeutic barrier to CAR T cell therapy, and it is currently unknown whether deletion of negative regulators in CAR T cells reshapes the endogenous immune landscape. To address this knowledge gap, we developed CAR T cells targeting B7-H3 in immune-competent osteosarcoma models and evaluated the intrinsic and extrinsic effects of deleting a potent negative regulator called Regnase-1 (Reg-1). Deletion of Reg-1 not only improved the effector function of B7-H3-CAR T cells but also endowed them with the ability to create a proinflammatory landscape characterized by an influx of IFN{gamma}-producing endogenous T cells and NK cells and a reduction of inhibitory myeloid cells, including M2 macrophages. Thus, deleting negative regulators in CAR T cells enforces a non-cell-autonomous state by creating a proinflammatory tumor microenvironment.

immunology↗

bioRxiv2023

Longevity interventions in Titan mice attenuate frailty and senescence accumulation

Wild-type murine models for aging research have lifespans of several years, which results in long experimental duration and late output. Here we explore the short-lived non-inbred Titan mouse as a mouse model to test longevity interventions. We show that Titan mice exhibit increased frailty and cellular senescence at an early age. Dietary intervention attenuates the frailty progression of Titan mice. Additionally, cyclic administration of the senolytic drug Navitoclax at early age increases the lifespan and reduces cellular senescence. Our data suggests that Titan mice can serve as a cost-effective and timely model for longevity interventions in mammals.

systems biology↗

bioRxiv2022

Augmenting CAR NK cell Anti-tumor Activity by Synapse Tuning

Introductory ParagraphChimeric antigen receptor (CAR) technologies have been clinically implemented for the treatment of hematological malignancies; however, solid tumors remain resilient to CAR therapeutics1-3. Natural Killer (NK) cells may provide an optimal class of immune cells for CAR-based approaches due to their inherent anti-tumor functionality. We sought to tune CAR synapses in NK cells by adding an intracellular scaffolding protein binding site to the CAR. We employed a PDZ binding motif (PDZbm) that specifically binds Scribble4 resulting in additional scaffolding crosslinking to enhance synapse formation and cell polarization5,6. Combined effects of this novel CAR design resulted in increased effector cell functionality in vitro and in vivo. Synapse-tuned CAR-NK cells exhibited amplified synaptic strength, number and abundance of secreted cytokines, enhanced killing of tumor cells, and prolonged survival with tumor clearance in two solid tumor models. Thus, synapse tuning has the potential to improve the efficacy of CAR-based cell therapeutics.

immunology↗

bioRxiv2022

Latent human herpesvirus 6 is reactivated in chimeric antigen receptor T cells

Cell therapies have yielded durable clinical benefits for patients with cancer, but the risks associated with the development of therapies from manipulated human cells are still being understood. For example, we currently lack a comprehensive understanding of the mechanisms of neurotoxicity observed in patients receiving T cell therapies, including recent reports of encephalitis caused by human herpesvirus 6 (HHV-6) reactivation1. Here, via petabase-scale viral RNA data mining, we examine the landscape of human latent viral reactivation and demonstrate that HHV-6B can become reactivated in human CD4+ T cells in standard in vitro cultures. Using single-cell sequencing, we identify a rare population of HHV-6 super-expressors (~1 in 300-10,000 cells) that possess high viral transcriptional activity in chimeric antigen receptor (CAR) T cell culture before spreading to infect other cells in vitro. Through the analysis of single-cell sequencing data from patients receiving cell therapy products that are FDA-approved2 or used in clinical studies3,4, we identify the presence of CAR+, HHV-6 super-expressor T cells in vivo. Together, our study implicates cell therapy products as a source of lytic HHV-6 reported in clinical trials1,5-7 and has broad implications for the design, production, and monitoring of cell therapies.

immunology↗

bioRxiv2018

Intravital optoacoustic ultrasound bio-microscopy reveals radiation-induced skull vasculopathy

Angiogenesis is critical in bone development and growth. Dense, large-scale, and multi-layered vascular networks formed by thin-walled sinusoidal vessels perfuse the plate bones and play an important role in bone repair. Yet, the intricate functional morphology of skull microvasculature remains poorly understood as it is difficult to visualize using existing intravital microscopy techniques. Here we introduced an intravital fully-transcranial imaging approach based on hybrid optoacoustic and ultrasound bio-microscopy, allowing for large-scale observations and quantitative analysis of the vascular morphology, angiogenesis, vessel remodeling, and subsurface roughness in murine skulls. Our approach also enabled high-throughput physiological studies to understand radiation-inhibited angiogenesis in the skull bone. We observed previously undocumented sinusoidal vascular networks spanning the entire skullcap, thus opening new vistas for studying the complex interactions between calvarian, pial, and cortical vascular systems.

bioengineering↗