Biology subjects

Spranger, S.

Publications and source records attributed to Spranger, S..

16 recordsLinked to original sources

bioRxiv2026

Radiation therapy synergizes with mRNA vaccination to overcome microglia-mediated suppression of dendritic cell migration and T cell priming in glioblastoma

Glioblastomas (GBMs) are uniformly fatal brain tumors resistant to immunotherapy, yet the mechanisms driving immune dysfunction remain poorly understood. Here we identify a tissue-specific mechanism of dendritic cell (DC) dysfunction contributing to GBM immune evasion. We demonstrate that while systemic immunity depends on type 1 conventional DCs (cDC1s), GBMs preferentially accumulate cDC2s with impaired antigen-presenting capacity. Further, microglia-derived GAS6 and PROS1 signaling through the AXL receptor on DCs suppresses DC activation and, critically, migration to tumor-draining lymph nodes. Pharmacologic AXL inhibition enhances DC migration and consequently anti-tumor immunity. Importantly, radiation therapy activates cDC1-mediated endogenous immune responses, which synergizes with mRNA vaccination to promote complete and durable immune-mediated tumor regression. These findings establish DC-mediated immunity as a therapeutic target in brain tumors and reveal a synergistic mechanism for combining radiation with personalized cancer vaccines.

cancer biology↗

bioRxiv2026

Modeling lung adenocarcinoma using layer-by-layer nanoparticles mitigates innate immune cell activation

Lung adenocarcinoma, driven frequently by KRAS and p53 mutations, remains a leading cause of cancer mortality. Current state-of-the-art genetically engineered mouse models often rely on viral delivery of recombinases, such as Cre recombinase, to initiate transformation. However, viral particles can infect and activate innate immune cells, thus potentially impacting studies of tumor-immune dynamics. Here, we develop a layer-by-layer (LbL) polyplex platform using poly({beta}-aminoester) (PBAE) polymers layered with poly-L-aspartic acid (PLD) to deliver Cre mRNA to lungs while avoiding immune cell transfection and activation. PLD-coated nanoparticles (PLD-NPs) exhibit stable mRNA encapsulation and efficient transfection in vitro, even after lyophilization and long-term storage. In KrasLSL-G12D/+;p53flox/flox (KP) mice, PLD-NPs initiate lung adenocarcinomas that mirror human histopathology without infecting or activating dendritic cells and alveolar macrophages, unlike lentiviral (LV) or adenoviral delivery methods. Single-cell transcriptional profiling revealed that LV administration drives long-term upregulation of antigen presentation and costimulatory machinery in lung-resident myeloid populations. This persistent immune activation is avoided by NP delivery. By uncoupling tumor initiation from innate immune activation, this platform enables the high-fidelity interrogation of tumor-immune dynamics, especially for non-inflammation-driven lung cancer.

immunology↗

bioRxiv2026

immgenT CD4: a reference landscape of mouse CD4+ T cell

CD4+ T cells are orchestrators of the immune system with diverse effector functions. Their full molecular diversity remains unclear due to the lack of a unified framework. Within the immgenT project, we profiled RNA, surface markers, and TCR clonotypes in conventional CD4+ T cells across >700 samples. Integration with a joint RNA-protein deep generative model revealed an ensemble of 20 CD4 states that account for all cells across tissues and challenges. Small, highly polarized clusters ("tips") that evoke Th1, Th2, Th17, and Tfh states co-exist with a majority of activated cells with mixed programs occupying "midland" states. Unlike CD8+ T cells, memory CD4+ cells largely mapped to the same states as effectors. Resting states proved quite diverse, and we uncovered unexpected similarities between Tfh and chronically stimulated states. Together, immgenT provides a unified molecular reference for CD4+ T cell diversity.

immunology↗

bioRxiv2026

Analysis of tumor-derived and cross-presented peptide antigens defines improved immunotherapeutic strategies

BackgroundCross-presentation of tumor antigens by antigen-presenting cells (APCs) is essential for initiating effective anti-tumor T cell immunity. The presence of cross-presenting immune cells across multiple solid tumors correlates with improved clinical outcomes. Despite the importance of this process, the identities and characteristics of tumor-derived MHC-I antigens that are cross-presented by APCs remain largely undefined, limiting rational design of targeted immunotherapies. MethodsWe performed an immunopeptidomic analysis of cross-presented glioblastoma (GBM) antigens on APCs, including bone marrow-derived macrophages, bone marrow-derived dendritic cells, and splenic dendritic cells, using SILAC labeling and in vitro co-culture systems. Additionally, we also profiled endogenous APC and tumor antigen repertoires. We made selected cross-presented antigen targets into mRNA vaccines and evaluated their immunogenicity in comparison to tumor endogenous antigens in vivo. ResultsWe identified over one thousand putative cross-presented GBM antigens. Comparative analysis of endogenous APC and tumor antigen repertoires revealed that cross-presented antigens possess distinct features and are predominantly shaped by intrinsic antigen processing and presentation pathways within APCs, resulting in limited cross-presentation of tumor-specific epitopes. Two doses of mRNA encoding cross-presented tumor-specific epitopes delayed tumor growth and elicited robust antigen-specific T cell responses. ConclusionOur findings define the landscape and constraints of tumor antigen cross-presentation in GBM and establish a framework for improved antigen selection in the development of next-generation GBM immunotherapies.

immunology↗

bioRxiv2026

Lymph node resident memory T cells retain effector capabilities by evading lung resident memory dysfunction.

Resident memory T cells (TRM) mediate localized immunity in barrier tissues while central memory T cells (TCM) recirculate through lymphoid organs to surveil for reinfection. Although TRM are classically associated with peripheral non-lymphoid tissues, they have also been identified within lymph nodes (LNRM) where the mechanisms guiding their formation and functional differences remain poorly understood. Here we used longitudinal antibody labeling to track the migratory history of memory T cells after influenza infection and demonstrate that CD69+CD103+ T cells are resident in the lymph node. LNRM accumulate evenly throughout the lung-draining lymph node and are present within all analyzed LN compartments including, the sub capsular sinus, T cell zone and germinal centers. Epigenetic and transcriptional profiling reveal that LNRM are uniquely poised for cytotoxicity whereas TRM in the lung (LungRM) resemble exhausted cells with elevated expression of inhibitory receptors and increased chromatin accessibility at the Pdcd1 locus. Regulatory network analysis of transcription factors, combined with target gene expression and chromatin accessibility, identified key regulons differentiating TCM, LNRM and LungRM states. Upon antigen re-encounter, LNRM are more proliferative, cytotoxic, and produce more IFN{gamma} compared to LungRM. Notably, we find that LNRM represent the most prevalent subset of memory T cells in human thoracic lymph nodes. These findings highlight functional heterogeneity in TRM and establish LNRM as a distinct and durable memory T cell population bridging features of circulating and tissue-resident cells.

immunology↗

bioRxiv2026

The CD8 immgenT framework as a universal reference of mouse CD8 Tαβ cell differentiation states

Mouse CD8+ T cell differentiation has been studied extensively in models of infections and tumors, yet no unified framework spans the full spectrum of immunological contexts. Within the immgenT project, we profiled RNA, surface markers, and TCR clonotypes in conventional CD8+ T cells across >600 samples, spanning multiple perturbations, tissues, and timepoints. Twenty-one clusters across naive, effector, circulating memory, tissue-resident memory, progenitor-exhausted, and terminally-exhausted CD8+ T cell compartments emerged, with striking molecular convergence across acute and chronic infections, tumors, autoimmunity, aging, and homeostasis, illustrating that shared transcriptional states support protective or dysfunctional outcomes depending on developmental history and microenvironment. We validate immgenT as a comprehensive reference by integrating external datasets from conditions not represented in immgenT and by defining a flow cytometry panel spanning the CD8+ T cell landscape. Thus, immgenT-CD8 provides a molecular framework for harmonizing CD8+ T cell literature and clarifies relationships across diverse immune challenges.

immunology↗

bioRxiv2025

PD-1 blockade during T cell priming enhances long-term protection against metastatic tumors by epigenetically tuning T cell exhaustion

In cancer, CD8+ T cell responses are dominated by exhausted T cells, which can be reinvigorated using immune checkpoint blockade therapy and can control large tumors. However, it remains unclear which T cell fate best supports long-term immunity following tumor regression or clearance and a period of minimal antigen load. This question is particularly relevant following surgical tumor resection, when tuning the immune system could prevent recurrence. To determine which T cell fate provides durable protection following surgery and metastatic rechallenge, we modulated T cell priming using anti-PD-1, IFN-{beta} or agonistic anti-CD40 and assessed effects on CD8+ T cell differentiation and overall survival. IFN-{beta} and anti-CD40 promoted effector and memory-like T cell states, respectively, whereas anti-PD-1 did not markedly alter T cell differentiation, yet conferred the greatest survival benefit against metastatic tumors. Notably, anti-PD-1 induced epigenetic remodeling, which was detectable upon metastatic recall, consistent with the maintenance of a circulatory intermediate-exhausted T cell state. Thus, while effector and memory precursor-like T cells could be generated with IFN-{beta} and agonistic anti-CD40, only the intermediate-exhausted T cell state driven by anti-PD-1 supported durable anti-tumor immunity. SummaryThis study shows that PD-1 blockade during T cell priming promotes a circulatory intermediate-exhausted CD8 T cell state that uniquely supports durable anti-tumor immunity after surgical resection and metastatic challenge, outperforming effector or memory-like T cell responses generated by IFN-{beta} or CD40 agonist treatment, respectively.

immunology↗

bioRxiv2024

Bimodal cell mass distribution separates CD8+ T cells into two distinct types with divergentdifferentiation dynamics

T cells are central to immune defense, yet existing molecular and phenotypic assays do not fully capture a cells intrinsic immune potential. Here we show that a single physical property, buoyant mass, reveals hidden heterogeneity within phenotypically similar, resting CD8+ T cells. Using suspended microchannel resonator measurements, we identify two distinct populations: "light" cells, enriched for mitochondrial content but prone to delayed activation and exhaustion, and "heavy" cells, biosynthetically poised for proliferation and memory formation. In patients with melanoma receiving immune checkpoint blockade, pre-treatment buoyant mass profiling of circulating T cells predicted therapeutic response with an accuracy comparable with standard tumor-derived biomarkers. Our findings establish buoyant mass as a label-free, stimulation-independent measure of systemic T cell fitness, providing a rapid and broadly applicable framework for immune profiling and response prediction in cancer and beyond.

biophysics↗

bioRxiv2024

Mutant p53 Exploits Enhancers to Elevate Immunosuppressive Chemokine Expression and Impair Immune Checkpoint Inhibitors in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer without effective treatments. It is characterized by activating KRAS mutations and p53 alterations. However, how these mutations dysregulate cancer-cell-intrinsic gene programs to influence the immune landscape of the tumor microenvironment (TME) remains poorly understood. Here, we show that p53R172H establishes an immunosuppressive TME, diminishes the efficacy of immune checkpoint inhibitors (ICIs), and enhances tumor growth. Our findings reveal that the upregulation of the immunosuppressive chemokine Cxcl1 mediates these pro-tumorigenic functions of p53R172H. Mechanistically, we show that p53R172H associates with the distal enhancers of the Cxcl1 gene, increasing enhancer activity and Cxcl1 expression. p53R172H occupies these enhancers in an NF-{kappa}B-pathway-dependent manner, suggesting NF-{kappa}Bs role in recruiting p53R172H to the Cxcl1 enhancers. Our work uncovers how a common mutation in a tumor-suppressor transcription factor appropriates enhancers, stimulating chemokine expression and establishing an immunosuppressive TME that diminishes ICI efficacy in PDAC. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/609802v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@b2354dorg.highwire.dtl.DTLVardef@1c96300org.highwire.dtl.DTLVardef@829f26org.highwire.dtl.DTLVardef@19e7d2e_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2023

Lung cancer-intrinsic SOX2 expression mediates resistance to checkpoint blockade therapy by inducing Treg-dependent CD8+ T cell exclusion

Tumor-intrinsic signaling pathways can drastically affect the tumor immune microenvironment (TME), promoting tumor progression and resistance to immunotherapy by excluding immune cell populations from the tumor. Several tumor-cell intrinsic pathways have been reported to affect myeloid cell infiltration and downstream T cell infiltration. Clinical evidence suggests that the exclusion of cytotoxic T cells from the tumor core likewise mediates resistance. Here, we find that tumor cell-intrinsic SOX2 expression induces the exclusion of cytotoxic T cells from the tumor core and promotes resistance to checkpoint blockade therapy. CD8+ T cell exclusion was dependent on regulatory T cell-mediated suppression of tumor vasculature. Depleting tumor-infiltrating regulatory T cells via Glucocorticoid-Induced TNFR-Related (GITR) restored CD8+ T cell infiltration and reduced tumor growth in combination with checkpoint blockade therapy. SignificanceWe identified tumor cell-intrinsic SOX2 expression in lung cancer as a mechanism of resistance to immunotherapy. SOX2 expression increases regulatory T cell populations in the TME, negatively affecting the tumor vasculature and blunting CD8+ T cell infiltration into the tumor core. This effect could be reverted by targeting regulatory T cells with anti-GITR therapy.

immunology↗

bioRxiv2023

Differentiation and Expansion of Tumor-Infiltrating T Cell Clonotypes Occurs in the Spleen Following Immune Checkpoint Blockade

Immune checkpoint blockade (ICB) enhances tumor-reactive T cell responses against cancer, leading to long-term tumor control and survival in a fraction of patients. Given the increasingly recognized complexity of T cell differentiation that occurs in response to chronic antigen stimulation, it remains unclear precisely which T cell differentiation states are critical for the response to ICB, as well as the anatomic sites at which ICB-mediated reinvigoration of these T cells occurs. We used paired single-cell RNA and T cell receptor (TCR) sequencing to profile endogenous, tumor-reactive CD8+ T cells isolated from tumors, tumor-draining lymph nodes, and spleens of mice treated with ICB. We identified an intermediate-exhausted population of T cells in the spleen which underwent the greatest expansion in response to ICB and gave rise to the majority of tumor-infiltrating clonotypes. Increasing concentrations of antigen in the spleen perturbed the differentiation of this phenotype towards a divergent exhausted_KLR state, resulting in reduced numbers of tumor-infiltrating T cells and blunted ICB efficacy. Likewise, an analogous population of exhausted_KLR CD8+ T cells in matched human tumor and blood samples and exhibited diminished tumor-trafficking ability. These data demonstrate that the spleen is a critical anatomic site for coordinating the differentiation of tumor-infiltrating clonotypes and their expansion in response to ICB.

immunology↗

bioRxiv2022

Decoupled neoantigen cross-presentation in tumors with high intratumor heterogeneity reduces dendritic cell activation to limit anti-tumor immunity

Cancer immunotherapies, in particular checkpoint blockade immunotherapy (CBT), can induce control of cancer growth, with a fraction of patients experiencing durable responses. However, the majority of patients currently do not respond to CBT and the molecular determinants of resistance have not been fully elucidated. Mounting clinical evidence suggests that the clonal status of neoantigens (NeoAg) impacts the anti-tumor T cell response. High intratumor heterogeneity (ITH), where the majority of NeoAgs are expressed subclonally, is correlated with poor clinical response to CBT and poor infiltration with tumor-reactive T cells. However, the mechanism by which ITH blunts tumor-reactive T cells is unclear. We developed a transplantable murine lung cancer model to characterize the immune response against a defined set of NeoAgs expressed either clonally or subclonally to model low or high ITH, respectively. Here we show that clonal expression of a weakly immunogenic NeoAg with a relatively strong NeoAg increased the immunogenicity of tumors with low but not high ITH. Mechanistically we determined that clonal NeoAg expression allowed cross-presenting dendritic cells to acquire and present both NeoAgs. Dual NeoAg presentation by dendritic cells was associated with a more mature DC phenotype and a higher stimulatory capacity. These data suggest that clonal NeoAg expression can induce more potent anti-tumor responses due to more stimulatory dendritic cell: T cell interactions. Therapeutic vaccination targeting subclonally expressed NeoAgs could be used to boost anti-tumor T cell responses.

immunology↗

bioRxiv2021

Deciphering the tumor-specific immunopeptidome in vivo with genetically engineered mouse models

Effective immunosurveillance of cancer requires the presentation of peptide antigens on major histocompatibility complex Class I (MHC-I). Recent developments in proteomics have improved the identification of peptides that are naturally presented by MHC-I, collectively known as the "immunopeptidome". Current approaches to profile tumor immunopeptidomes have been limited to in vitro investigation, which fails to capture the in vivo repertoire of MHC-I peptides, or bulk tumor lysates, which are obscured by the lack of tumor-specific MHC-I isolation. To overcome these limitations, we report here the engineering of a Cre recombinase-inducible affinity tag into the endogenous mouse MHC-I gene and targeting of this allele to the KrasLSL-G12D/+; p53fl/fl (KP) mouse model (KP; KbStrep). This novel approach has allowed us to isolate tumor-specific MHC-I peptides from autochthonous pancreatic ductal adenocarcinoma (PDAC) and lung adenocarcinoma (LUAD) in vivo. With this powerful analytical tool, we were able to profile the evolution of the LUAD immunopeptidome through tumor progression and show that in vivo MHC-I presentation is shaped by post-translational mechanisms. We also uncovered novel, putative LUAD tumor associated antigens (TAAs). Many peptides that were recurrently presented in vivo exhibited very low expression of the cognate mRNA, provoking reconsideration of antigen prediction pipelines that triage peptides according to transcript abundance. Beyond cancer, the KbStrep allele is compatible with a broad range of Cre-driver lines to explore antigen presentation in vivo in the pursuit of understanding basic immunology, infectious disease, and autoimmunity.

cancer biology↗

bioRxiv2021

Cell lineage as a predictor of immune response in neuroblastoma

Immunotherapy for patients with neuroblastoma has met with limited success, partly due to an incomplete understanding of the mechanisms underlying immune responsiveness in this clinically and genetically heterogenic tumor. Here, we undertook an unbiased analysis using dimension reduction and UMAP visualization of transcriptional signatures derived from 498 primary neuroblastoma tumors. Four distinct clusters based on differentially expressed genes emerged, of which one, representing about 30% and comprising mainly of MYCN-nonamplified tumors, was notable for the high expression of genes associated with both immune response activation and suppression. This capacity to elicit a productive immune response resided exclusively in tumors with dominant populations of undifferentiated, neural crest-like or mesenchymal cells; by contrast, tumors comprising primarily of committed, adrenergic neuron-like cells were less immunogenic. Mesenchymal neuroblastoma cells were enriched for innate and adaptive immune gene signatures, demonstrated engagement with cytotoxic T and natural killer cells, and induced immune cell infiltration in an immunocompetent mouse model. Transcriptional or targeted therapy-induced reprogramming of adrenergic cells to the mesenchymal state led to reactivation of tumor cell-intrinsic immune genes. Key immune response genes in adrenergic tumor cells were found to be epigenetically silenced by the PRC2 complex, and such repression could be relieved by either mesenchymal cell state reprogramming or EZH2 inhibition, leading to increased activation of natural killer cells by the tumor cells. These data identify cell lineage as a major determinant of the immunogenic potential in neuroblastoma that could be used to stratify patients who are most likely to benefit from immunotherapy.

cancer biology↗

bioRxiv2020

Increased demand for NAD+ relative to ATP drives aerobic glycolysis

Aerobic glycolysis, or preferential fermentation of glucose-derived pyruvate to lactate despite available oxygen, is a hallmark of proliferative metabolism that is observed across many organisms and conditions. To better understand why aerobic glycolysis is associated with cell proliferation, we examined the metabolic consequence of activating the pyruvate dehydrogenase complex (PDH) to increase mitochondrial pyruvate oxidation at the expense of fermentation. We find that increasing PDH activity impairs cell proliferation by reducing the nicotinamide adenine dinucleotide cofactor ratio (NAD+/NADH). This change in NAD+/NADH ratio is caused by an increase in mitochondrial membrane potential that impairs mitochondrial electron transport and NAD+ regeneration. Uncoupling mitochondrial respiration from ATP synthesis or increasing ATP hydrolysis restores NAD+/NADH homeostasis and proliferation even when glucose oxidation is increased. These data suggest that when the demand for NAD+ to support oxidation reactions exceeds the demand for ATP consumption in cells, NAD+ regeneration by mitochondrial respiration becomes constrained, promoting fermentation despite available oxygen. This argues that cells engage in aerobic glycolysis when the cellular demand for NAD+ is in excess of the cellular demand for ATP.

biochemistry↗

bioRxiv2019

Development of Human Neuroblastomas in Mouse-Human Neural Crest Chimeras

Neuroblastoma (NB), derived from the neural crest (NC), is the most common pediatric extracranial solid tumor. Here we establish a platform that allows studying human NBs in mouse-human NC chimeras. Chimeric mice were produced by injecting human NC cells carrying NB relevant oncogenes in-utero into gastrulating mouse embryos. The mice developed tumors composed of a heterogenous cell population that closely resembled that seen in primary NBs of patients but were significantly different from homogenous tumors formed in xenotransplantation models. The human tumors emerged in immunocompetent hosts and were extensively infiltrated by mouse cytotoxic T cells reflecting a vigorous host anti-tumor immune response. However, the tumors blunted the immune response by inducing infiltration of regulatory T cells and expression of immune checkpoints similar to escape mechanisms seen in human cancer patients. Thus, this experimental platform allows studying human tumor initiation, progression, manifestation and tumor - immune-system interactions in an animal model system.

cancer biology↗