Biology subjects

Wolff, D.

Publications and source records attributed to Wolff, D..

7 recordsLinked to original sources

bioRxiv2026

Timed STING Inhibition Mitigates Gastrointestinal GvHD While Preserving Graft-versus-Leukemia Activity After Allo-HSCT

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is curative for hematological malignancies but limited by graft-versus-host disease (GvHD), in which donor T cells damage host tissues. Current prophylaxis broadly suppresses donor immunity, often compromising the beneficial graft-versus-leukemia (GvL) response, highlighting the need for strategies that uncouple GvHD from GvL. The cGAS-STING pathway can be strongly activated during conditioning-induced tissue damage and represents a potential therapeutic target. However, its context-dependent roles in inflammation and homeostasis have constrained its clinical translation. Here, we show that "timed" administration of the covalent STING inhibitor H151 before conditioning reduced GvHD-associated mortality without impairing GvL in murine allo-BMT models. Donor T cell activation and effector function were preserved, indicating that the protective effect operates at the level of GvHD target tissues rather than through systemic immunosuppression. Timed STING inhibition protected the intestinal epithelium by limiting apoptosis, preserving intestinal stem cell function, and sustaining metabolic fitness during conditioning-induced injury, independently of type I interferon (IFN-I) signaling. In allo-HSCT patients, low intestinal STING expression is associated with reduced transplant-related mortality. Together, these findings identify timed STING inhibition as a tissue-protective prophylactic strategy that could be incorporated into existing conditioning regimens to enhance efficacy while minimizing toxicity.

immunology↗

bioRxiv2026

Targeting phosphodiesterase 10A disrupts MAPK signaling pathways in the tumor microenvironment to unleash antitumor immunity

Phosphodiesterase 10A (PDE10A), a cyclic nucleotide-degrading enzyme, is overexpressed in various human cancers. While PDE10A inhibition using small-molecule inhibitors or gene silencing suppresses tumor growth in xenograft models, its precise mechanism of action and immunological impact remain unclear. Here, we report that ADT-030, a novel PDE10A inhibitor, exhibits potent cytotoxicity against a broad range of murine tumor cell lines. ADT-030 is orally bioavailable and effectively suppresses tumor growth across multiple syngeneic mouse models. Notably, its efficacy is diminished in immunodeficient mice or upon CD8+ T cell depletion, highlighting a critical dependence on host immunity. The immunostimulatory properties of ADT-030 are further supported by its ability to induce immunogenic tumor cell death and promote dendritic cell (DC) maturation, its reliance on Batf3-expressing DCs to elicit antitumor CD8+ T cell response, and its synergy with anti-PD-1 therapy. Comprehensive immune profiling in the 4T1 breast cancer model, both in orthotopic and metastatic settings, revealed that ADT-030 selectively reduces myeloid-derived suppressor cells (MDSCs) while normalizing the immune landscape within the tumor. Mechanistically, ADT-030 disrupts multiple components of the mitogen-activated protein kinase (MAPK) signaling network in both tumor cells and MDSCs, leading to induction of apoptosis in these populations. These findings highlight the multi-faceted impact of PDE10A inhibition as a therapeutic strategy that not only disrupts tumor-intrinsic oncogenic signaling to inhibit tumor progression but also reshapes the tumor immune microenvironment to unleash antitumor immunity.

immunology↗

bioRxiv2026

Indomethacin exerts both cyclooxygenase inhibition-dependent and independent mechanisms to enhance chemo-immunotherapy in mice

Nonsteroidal anti-inflammatory drugs (NSAIDs) primarily act by inhibiting cyclooxygenases (COX1 and COX2), thereby reducing production of the proinflammatory mediator prostaglandin E2 (PGE2). Because PGE2 is a critical driver of cancer progression and tumor immune evasion, this has motivated interest in combining NSAIDs with chemotherapy or immunotherapy for cancer treatment. However, since COX and PGE2 levels vary across tumor types, it remains unclear whether tumor PGE2 abundance solely dictates tumor response to NSAID-based therapies. Here, we investigated the therapeutic potential of indomethacin (Indo), a prototypical NSAID, in combination with cyclophosphamide (CTX), a widely used chemotherapeutic agent with immunostimulatory properties. Metronomic administration of Indo significantly enhanced the antitumor efficacy of CTX in multiple murine tumor models exhibiting variable COX2 and PGE2 levels, including CT26, MC38, 4T1 and A20. The antitumor effects of CTX+Indo required CD8 T cells and T-cell trafficking from tumor-draining lymph nodes and were further potentiated by anti-PD-1 blockade. Single-cell RNA sequencing (scRNA-seq) revealed that responsive CT26 tumors exhibited a reprogrammed tumor immune microenvironment (TIME), marked by increased effector CD8 T-cell infiltration, reduced immunosuppressive myeloid populations, and enhanced interferon signaling in tumor cells. Importantly, Indo retained therapeutic benefit following CTX even in tumors incapable of producing PGE2, demonstrating a critical contribution of COX-independent mechanisms, particularly inhibition of tumor-intrinsic oncogenic RAS signaling, to the enhanced efficacy of the CTX+Indo combination. Collectively, our results provide strong preclinical rationale for leveraging the COX/PGE2 and RAS dual inhibitory capacities of NSAIDs to enhance the efficacy of chemotherapy and immunotherapy.

immunology↗

bioRxiv2025

A microbial metabolite protects against graft-versus-host disease via mTORC1 and STING-dependent intestinal regeneration

Changes in the intestinal microbiome and microbiota-derived metabolites predict clinical outcomes after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Here, we report that desaminotyrosine (DAT), a product of bacterial flavonoid metabolism, correlates with improved overall survival and reduced relapse rates in allo-HSCT patients. In preclinical mouse models, treatment with synthetic DAT prevents graft-versus-host disease by protecting the intestinal barrier and promoting intestinal regeneration and contributes to graft-vs.-leukemia responses. DATs beneficial effects on intestinal regeneration remain effective despite broad-spectrum antibiotics-induced dysbiosis, also when administered by fecal microbiota transfer with flavonoid-degrading F. plautii. Mechanistically, DAT promotes mTORC1-dependent activation and proliferation of intestinal stem cells, with concomitant engagement of the innate immune receptor STING required to mitigate metabolic stress and maintain an undifferentiated stem cell state independently of type-I interferon responses. Additionally, DAT can skew T cells towards an effector phenotype to modulate graft-versus-leukemia responses. Our data uncover DATs dual, tissue- and immune-modulating properties and underscore its potential in precision microbiome-based therapies to improve tissue regeneration and minimize immune-mediated side effects.

immunology↗

bioRxiv2024

De novo designed pMHC binders facilitate T cell induced killing of cancer cells

The recognition of intracellular antigens by CD8+ T cells through T-cell receptors (TCRs) is central to adaptive immunity, enabling responses against infections and cancer. The recent approval of TCR-gene-edited T cells for cancer therapy demonstrates the therapeutic advantage of using pMHC recognition to eliminate cancer. However, identification and selection of TCRs from patient material is complex and influenced by the TCR repertoire of the donors used. To overcome these limitations, we here present a rapid and robust de novo binder design platform leveraging state-of-the-art generative models, including RFdiffusion, ProteinMPNN, and AlphaFold2, to engineer minibinders (miBds) targeting the cancer-associated pMHC complex, NY-ESO-1(157-165)/HLA-A*02:01. By incorporating in silico cross-panning and molecular dynamics simulations, we enhanced specificity screening to minimise off-target interactions. We identified a miBd that exhibited high specificity for the NY-ESO-1-derived peptide SLLMWITQC in complex with HLA-A*02:01 and minimal cross-reactivity in mammalian display assays. We further demonstrate the therapeutic potential of this miBd by integrating it into a chimeric antigen receptor, as de novo Binders for Immune-mediated Killing Engagers (BIKEs). BIKE-transduced T cells selectively and effectively killed NY-ESO-1+ melanoma cells compared to non-transduced controls, demonstrating the promise of this approach in precision cancer immunotherapy. Our findings underscore the transformative potential of generative protein design for accelerating the discovery of high-specificity pMHC-targeting therapeutics. Beyond CAR-T applications, our workflow establishes a foundation for developing miBds as versatile tools, heralding a new era of precision immunotherapy.

immunology↗

bioRxiv2024

Tissue-adapted Tregs harness inflammatory signals to promote intestinal repair from therapy-related injury

Intestinal stem cells (ISC) promote tissue repair after genotoxic or immune-mediated injury. However, ISCs are particularly sensitive to various stressors and primary targets of overwhelming immune responses such as interferon-{gamma} (IFN{gamma})-mediated killing. In mouse models of gut damage and biopsies from patients having undergone allo-hematopoietic stem cell transplantation, we observed IFNy expression by intestinal Treg cells. Treg cells leverage combined IFN{gamma} and interleukin 10 (IL-10) stimulation of ISCs to nurture the growth of intestinal organoids through the activation of the mTORC1 and Myc pathways. Similarly, Treg cells or the combined addition of recombinant IFN{gamma} and IL-10 promote the regeneration of organoids after irradiation. Exposure of organoids to Wnt- or EGF-free culture conditions revealed distinct growth factor-like properties of IFN{gamma} and IL-10. While IFN{gamma} induced epithelial proliferation and differentiation, combined addition of IFN{gamma} and IL-10 led to balanced proliferation, ensuring ISC maintenance. Our results uncover a context-dependent role of inflammatory signaling in ISC, through which Treg cells promote epithelial repair.

immunology↗

bioRxiv2021

Biomass, microbial composition and functions are responsible for the differential removal of trace organic chemicals in biofiltration systems

Biofiltration processes help to remove trace organic chemicals (TOrCs) both in wastewater and drinking water treatment systems. However, the detailed TOrCs biotransformation mechanisms as well as the underlying drivers behind the variability of site specific transformation processes remain elusive. In this study, we used laboratory batch incubations to investigate the biotransformation of 51 TOrCs in eight bioactive filter materials of different origins treating a range of waters, from wastewater effluents to drinking water. Microscopy, 16S rRNA amplicon and whole metagenome sequencing for assessing associations between the biotransformation rate constants, microbial composition and genetic potential complemented chemical analysis. We observed strong differences in the mean global removal of TOrCs between the individual sand filters (-1.4% to 58%), which were mirrored in overall biomass, microbial community composition, and enzyme encoding genes. From the six investigated biomass markers, ATP turned out to be a major predictor of the mean global biotransformation rate, while compound specific biotransformations were correlated with the microbial community composition. High biomass ecosystems were indicated in our systems by a dominance of Nitrospirae, but individual TOrC biotransformation was statistically connected to rare taxa (< 2%) such as Hydrogenophaga, or indiviudal functions such as the enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase encoding genes. In general, this study provides new insights into so far rarely addressed variability of TOrCs biotransformation. We propose novel biological indicators for the removal performance of TOrCs in biofiltration systems, highlighting the role of living biomass in predicting and normalizing the global transformation, and the role of the microbial community for the individual transformation of TOrCs in engineered and natural systems. Contribution to the Field StatementTrace organic chemicals (TOrCs) are an emerging problem in the aquatic environment that has attracted global attention over the last decade. Recent research efforts on this topic have increased our knowledge on the transformation of TOrCs and various technologies have been developed to improve their removal. In this study, we investigated a wide range of biotransformation of TOrCs by eight sand filter materials from wastewater and water treatment plants. Biotransformation rate constants were calculated using first-order kinetics to evaluate TOrC removal performance. We reevaluated the role of biomass and could thus explain a greater part of the global TOrC removal performance. The remaining variation in removal rates of individual compounds correlated with the microbiome of the biofilter. Rare biosphere lineages and specific enzyme categories genes were correlated with the removal of certain compounds. In summary, our research identified future indicators for successful biotransformation of TOrCs in biofilter systems.

microbiology↗