Browse Articles
Discover research articles across all indexed journals
Effect of inhibiting pathogen recognition receptor function with small molecules on ovarian cancer cells in vitro 2258086
Abstract Introduction The American Cancer Society estimates that within the year of 2025, around 20,000 women in the USA will receive a diagnosis of ovarian cancer (OvCa). Until the advent of PARP inhibitors (PARPis), the standard-of-care for first-line treatment of advanced ovarian cancer consisted of cytoreductive surgery and chemotherapy. Even with the use of PARPis, OvCa has poor survival outcomes, with only around 40% and 20% of women in average surviving 5 years after diagnosis (stage III and IV respectively). Thus, new treatments are needed to improve the outcomes for people with this disease. Pathogen recognition receptors (PRRs) are a group of immune proteins that recognize and bind structures that are highly conserved on many pathogens. In case of a viral infection, upon binding to their respective viral ligands, PRRs activate a signal cascade and ultimately cause downstream effects such as the release of cytokines, leading to an antiviral response. PRRs have been involved both in tumor resistance and progression and we speculate that targeting these molecules in tumor cells can be a future therapeutic option. Methods In these studies, we treated mouse (ID8 and BPPNM) and human (A2780, SKOV3) OvCa cells with small molecule inhibitors of TLR3 (Cu-CPT4a), TLR4 (TAK242), TLR7 &9 (E6446), PKR (PKR-IN-C16), RIG (RIG-012), and STING (H-151). We investigated the effect of the drugs on tumor cell viability, migration, and generation of spheroids and their synergism with oncolytic herpesvirus (DNA genome) and reovirus (RNA genome). Results We observed that of all the drugs studied, RIG-012 and E6446 had the highest capability to inhibit, in a dose-dependent fashion, the proliferation, migration and spheroid size of mouse and human OvCa cell cultures. In addition, E6446 was able to increase the efficacy of oncolytic herpesvirus on human ovarian cancer cells. Conclusion These findings suggest that targeting particular PRR in cancer cells could be a therapeutic approach for OvCa. Funding Source Ohio University-HCOM RSAC grant RP2404 (FB) Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)
Targeted Immunotherapy for Regulatory T Cells 2307761
Abstract Introduction Underperformance and dysfunction of CD4+ regulatory T cells (Tregs) has been implicated in the pathogenesis of many autoimmune diseases. As such, multiple approaches toward Treg immunotherapy are being developed, most of which require ex vivo expansion and/or manipulation of Tregs, and in vivo strategies remain challenging to accomplish. Here, we hypothesized that constitutively high expression of the high-affinity IL2 receptor on Tregs could be exploited to target selective uptake of mRNA-LNPs by Tregs, enabling the potential development of an in vivo immunotherapy platform. Methods IL2 or αCD25 was conjugated to LNPs containing N1-Methylpseudouridine-substituted mRNA for eGFP using a SATA-maleimide based strategy. In vivo experiments were done using 6-week-old female C57BL/6 mice given 5 µg of LNP intravenously. In vitro experiments were performed using normal donor human splenocytes or PBMCs. Targeting was assessed using eGFP expression and flow cytometry. Results To define the optimal method to target Tregs with mRNA-LNPs, we first compared αCD25 vs IL-2 conjugated LNPs. IL2-LNPs demonstrated superior targeting in vivo of splenic Tregs compared to αCD25-LNPs in both frequency (69.7% vs. 41.9% eGFP+ respectively, p = 0.03) and expression (1399 vs. 424 eGFP MFI, p = 0.01) 24 hours after delivery. IL2-LNP targeted Tregs expressing eGFP were present in spleen, lymph node, and blood 24 hours post-treatment (40-70% eGFP+) and remained detectable for at least 7 days. Little background uptake of IL2-LNPs was observed in other immune cell subsets. Finally, IL2-LNPs also delivered mRNA effectively to FoxP3+Tregs in vitro in human splenocytes in a dose-dependent manner with little uptake by other cell subsets. Conclusion Altogether, these data demonstrate that IL2-LNPs are an efficient and effective method of targeting Tregs in situ. Future studies will apply this powerful tool to transiently enhance and alter Treg function in vivo for interventional and therapeutic strategies in autoimmune disease models. Funding Source Breakthrough T1D (3-SRA-2024-1612-S-B) Topic Categories Therapeutic Approaches to Autoimmunity (THER)
Imprinting of regulatory T cells by gut microbiota early in life 2336688
Abstract Introduction The gut microbiota is essential for immune system maturation in early life. The introduction of solid food at weaning triggers a transient immune response, the weaning reaction, which protects against colitis and colorectal cancer later in life. However, the impact of dietary-induced microbial dysbiosis during weaning on long-term intestinal homeostasis remains unclear. We aimed to determine whether and how microbial dysbiosis during weaning affects mucosal homeostasis and susceptibility to colitis and colorectal cancer in adulthood. Methods Mice were fed diets differing in fiber quantities during weaning. After weaning, offspring were maintained on standard chow. Microbiota composition, and intestinal immune cell populations were studied. Adult susceptibility was evaluated using DSS-induced colitis, AOM/DSS-induced colitis-associated cancer, and spontaneous intestinal cancer (ApcMin/+) models. To study the contribution of T cells, scRNA-seq was performed on CD4-positive T cells, and transgenic mice were used to track specific, transient CD4+ T cell subsets. Bulk RNA-seq of the colon and T cell transfer experiments were also conducted. The causal role of early-life microbiota was tested by transferring microbiota into germ-free mice. Results Early-life dietary variation induced subtle changes in microbiota, reflected in shifts in immune cell populations at weaning. These early differences were associated with altered adult responses to colitis and colorectal cancer, indicating lasting effects on mucosal homeostasis. Specific CD4+ T cell subsets were modulated by early-life microbiota, and colon transcriptomics revealed persistent changes. Microbiota transfer into germ-free neonates demonstrated that early-life microbial communities alone were sufficient to shape long-term intestinal outcomes, highlighting a critical window during weaning for immune programming. Conclusion Microbial composition during weaning plays a central role in establishing long-term mucosal homeostasis. Funding Source This project supported by the European Research Council Starting Grant, Swiss National Science Foundation, Helmut Horten Stiftung, Swiss Cancer Research Foundation, Kenneth Rainin Foundation, Inselspital, Ruth & Arthur Scherbarth Stiftung, Novartis Founda Topic Categories Mucosal and Regional Immunology (MUC)
Activating systemic immunity through engineered lymph node-homing T cells 2335174
Abstract Introduction Lymph nodes (LNs) serve as the critical education centers of adaptive immunity to combat pathogens while simultaneously protecting host tissues through peripheral tolerance induction. LNs are often co-opted by tumors to induce tumor-specific immune tolerance yet are also key sites of immunotherapy response. Here, we aim to develop a cell therapy capable of reeducating systemic anti-tumor immunity within LNs. Methods Naïve T cells continuously circulate between blood and LNs through a process that is dynamically regulated by multiple cell surface receptors. We have harnessed these mechanisms by engineering T cells to constitutively express the cell surface protein responsible for initiating the LN-homing cascade, L-selectin. We transduce T cells using viral vectors encoding a wild-type (WT L-sel) or engineered L-selectin variant (L-sel mut). To assess selective LN-homing capacity, we adoptively transfer our engineered cells into mice and subsequently quantify tissue accumulation by flow cytometry. Results Flow cytometry of cell surface L-selectin expression reveals a 6-fold increase on our engineered T cells compared to control cells. Upon PMA/Ionomycin stimulation, 91.2% of L-sel mut cells maintain cell surface expression of L-selectin in comparison to 28.9% of WT L-sel and 7.8% of control T cells. Furthermore, adoptive transfer of equal proportions of control, WT L-sel, and L-sel mut T cells yielded selective accumulation of the engineered cells within LNs. Conclusion By harnessing the intrinsic mechanisms that govern T cell LN-homing, we have engineered T cells that maintain expression of L-selectin on the cell surface, endowing them with a propensity for LN-homing. By combining these technologies with tumor recognition domains and armoring approaches, these therapies have the potential to elicit anti-tumor immunity within LNs and systemically. Funding Source NIAID DP2 Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)
Reversing defective priming in tumor-bearing hosts to rescue CD8 T cell function 2260686
Abstract Introduction Tumor-specific CD8 T cells (TST) are often dysfunctional and fail to halt cancer progression. While chronic antigen stimulation is required to maintain the dysfunctional state , how T cell dysfunction initially arises in tumors was less clear. We recently demonstrated that TST lose effector function within hours of activation in tumor-bearing hosts; epigenetic and transcriptional analysis suggested that TST failed to activate inflammation-associated TF, resulting in loss of effector function. We therefore tested whether pathogen-associated molecular patterns (PAMP) signaling during initial priming could rescue T cell dysfunction in tumor-bearing hosts. Methods We used a preclinical liver cancer model in which tumors express the cognate antigen for transferred TCR-transgenic CD8 T cells (TCR-TAG), while antigen-free LM was used to provide PAMP signaling. Outcomes assessed were tumor outgrowth and T cell differentiation and function, determined by flow cytometry, RNA-SEQ, and ATAC-SEQ. Results TCR-TAG adoptively-transferred into mice with advanced liver tumors rapidly became dysfunctional: unable to produce effector cytokines (TNF alpha, IFN gamma) or cytotoxic molecules (granzyme B; GZMB). Remarkably, a single LM treatment rescued effector function; TCR-TAG expressed cytokines and GZMB, resulting in remarkable tumor reduction and prolonged survival. LM-induced PAMP signaling reprogrammed TST, suppressing stem/memory-associated transcription factors (TF), such as TCF1, and activating STAT-family TF. Importantly, LM treatment rescued TST function only when delivered within 24-48h after initial priming. Conclusion Our findings demonstrate that pathogen-driven inflammatory signaling during priming is required for TST cytotoxicity. However, LM/PAMP can cause toxicity, thus we are testing genome engineering strategies to activate PAMP-associated TF in TST, independent of LM/PAMP, to generate potent tumor-targeting T cells for adoptive immunotherapy. Funding Source 2T32CA009592 Microenvironment Influences in Cancer Training Program Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)
The 1000+ mouse project: large-scale spatiotemporal parametrization and modeling of preclinical cancer immunotherapies 2309521
Abstract Introduction Preclinical CAR-T studies often monitor luciferase-labeled tumors in mice to gauge cytotoxicity, but analysis is frequently manual and hard to standardize. Here, we introduce maRQup (murine automatic Radiance Quantification and parametrization) for automated, spatiotemporal quantification and modeling of in-vivo tumor imaging. Methods maRQup is a Python pipeline that separates 1—5 mice per IVIS image, aligns anatomy by removing tails and vertically scaling mice, excludes slanted images, and computes average radiance per pixel as tumor burden. We curated >7,500 images from 1,060 mice across 37 experiments, with metadata on tumor dose, CAR targets, constructs, and CAR-T dose. Tumor trajectories were classified into growth/decay/relapse phases using thresholded changes in radiance, then fit with piecewise dynamical models (logistic growth for growth/relapse; exponential decay for decay) to extract kinetic rates. Results Complete tumor control was rare: among mice with initial tumor decay after CAR-T (43.2%), most later relapsed (77.5%). Comparing CD19 CARs with distinct costimulatory domains, CD19.CD28 more often prevented early tumor growth than CD19.4-1BB (29.7% vs 43.2% continued growth) yet relapsed more frequently (79.9% vs 58.6%). Increasing CAR-T dose improved immediate regression (reaching 100% at > 2 × 10^6 cells) but also simulatenously increased relapse frequency. Faster tumor growth was observed during the initial growth phase than during relapse. Anatomical mapping of tumor control revealed substantial spatial heterogenity in growth patterns, with the snout standing out as a particularly prominent relapse location. Conclusion maRQup delivers quantitative, statistically robust, and scalable readouts of preclinical CAR-T efficacy, exposing how construct choice, dose, and anatomical context shape distinct kinetic phases of tumor response, and providing a practical route to optimize immunotherapies. Funding Source National Cancer Institute Intramural funding Topic Categories Computational and Systems Immunology (COMP)
Eosinophil—macrophage crosstalk controls obesity-associated adipose inflammation and is stabilized by RELMα in a sex-dependent manner 2309540
Abstract Introduction Eosinophils are immune cells with terminal effector functions in type 2 immune responses, yet recent findings suggest that they exhibit functional plasticity and heterogeneity dependent on tissue-specific cues. Methods 10x Genomics Fixed RNA Profiling was performed on Siglec-F+ purified adipose eosinophils and macrophages from PBS-injected or Nippostrongylus brasiliensis-infected high fat diet-fed male and female C57BL6/J or RELMÉ’-deficient (KO) mice. Results Through analysis of single cell transcription patterns of eosinophils in the adipose tissue, we show that they could be divided into stable subtypes and that the differences between conditions explained the changes and transition between the subtype populations. Protective eosinophils subtypes, stabilized by the macrophage protein RELMa, dominate in females and with helminth infection and maintain M2 macrophages in a macrophage-eosinophil regulatory loop that protects against obesity through pathways such as CCL6-CCR3, thrombospondin and fibronectin signaling. In contrast, the strength and direction of this regulatory loop is perturbed in males and RELMa deficient mice with a shift to inflammatory M1 macrophages. Validation of the eosinophil subtypes and chemokine/chemokine receptor pairings was performed by spectral flow cytometry and adipose tissue section imaging. Further, through single-cell regulatory network inference and clustering (SCENIC) analysis, we identify transcription factor regulons associated with specific eosinophil subtypes including cell cycle and DNA replication factors (E2F) in C0 and C1 subtypes. Conclusion Collectively, these results provide a novel way to describe eosinophil heterogeneity and decipher the mechanism underlying changes in eosinophil subtype composition that influence pro-inflammatory or homeostatic effects. Manipulation of the regulons or ligand/receptor interactions provide a powerful opportunity to restore adipose homeostasis in obesity. Funding Source NIH R21AI180561, NIH R01AI191470, UCR School of Medicine Dean’s Postdoc to Faculty award, TRANSCEND fellowship from the California Institute of Regenerative Medicine (Award # EDUC4-12752). Topic Categories Innate Immune Responses and Host Defense: Cellular Mechanisms (INC)
E-cadherin and PD-1 interaction via their N-terminal ectodomains establishes a novel inhibitory axis modulating T cell function 2258851
Abstract Introduction E-cadherin, a member of the cadherin superfamily, is well known for mediating cell-cell adhesion. Recent studies suggest an immunomodulatory role, notably via interaction with the inhibitory receptor KLRG1 on NK cells and T cells. Using biophysical assays, in vitro T cell studies, and structure-guided mutagenesis, we identified and mapped a novel interaction between E-cadherin and PD-1, an inhibitory receptor primarily expressed on T cells. Methods The N-terminal ectodomains of E-cadherin and PD-1 were expressed and purified for interaction analysis by surface plasmon resonance. Fluorophore-conjugated E-cadherin tetramers were used in flow cytometry to assess binding to PD-1 on T cells. Functional outcomes of this interaction were evaluated, and bulk transcriptomic profiling was performed to elucidate underlying mechanisms. Structure-guided mutagenesis, combined with biophysical and functional assays, was employed to map the binding interface. Results Surface Plasmon Resonance analysis using purified N-terminal ectodomains of E-cadherin and PD-1 revealed a direct and specific interaction between the two proteins. A high-avidity E-cadherin probe confirmed binding on PD-1+ murine T cells. Functionally, this interaction significantly inhibited CD4+ and CD8+ T cell activity. Transcriptomic profiling revealed altered migration pathways and induction of FOXO signaling, consistent with a regulatory phenotype. Structure-guided mutagenesis, supported by biophysical and functional assays, indicated a distinct yet partially overlapping binding interface compared to the canonical PD-1:PD-L1 interaction. Conclusion Our findings reveal a previously unrecognized immunoregulatory axis in which E-cadherin directly engages PD-1 via N-terminal ectodomains to suppress T cell function. Given E-cadherin’s broad expression in peripheral tissues and some tumors, this novel PD-1:E-cadherin interaction may play a critical role in immune tolerance and tumor immune evasion. Funding Source MoE-STARS (Govt. of India) /STARS-2/2023-0284 dated 26-09-2023 Topic Categories Immune Response Regulation: Molecular Mechanisms (IRM)
Humoral responses in skin inflammation resulted from altered expression of epidermal Blimp-1 2308147
Abstract Introduction The skin epithelium provides both physical and immunological barriers essential for host defense. Our previous study demonstrated that inducible epidermal deletion of Prdm1 (encoding Blimp-1) in K5-CreER+Prdm1^f/f mice on a C57BL/6 background resulted in granulocyte-dominated chronic dermatitis, establishing Blimp-1 as a key regulator of epidermal immunity. However, the immunoregulatory role of keratinocyte-intrinsic Blimp-1, particularly in epithelial—immune and host—microbe interactions, remains largely unexplored. Moreover, the mechanisms underlying humoral immune responses during skin inflammation are still unclear. Methods To investigate how epidermal Blimp-1 regulates keratinocyte immune responses and humoral immunity, we generated mice with epidermal-specific deletion of Prdm1 on a BALB/c background, which is prone to type 2 humoral immune responses. In parallel, a high-throughput screening (HTS) platform using Prdm1^YFP/+ reporter keratinocytes was established to identify compounds that modulate Blimp-1 expression. Results Prdm1-deficient keratinocytes exhibited synergistic upregulation of the alarmin thymic stromal lymphopoietin (TSLP) upon Staphylococcus aureus challenge. Consistently, conditional knockout (CKO) mice developed a dominant type 2 immune milieu characterized by elevated IL-4, IL-13, and TSLP expression. This epithelial immune dysregulation was associated with staphylococcal dysbiosis, marked by Staphylococcus sciuri overgrowth, and induced robust production of S. sciuri—specific IgG1 and IgG2b antibodies. HTS of a 9,000-compound library identified several candidate compounds capable of modulating Blimp-1 expression. Conclusion These findings indicate that epidermal Blimp-1 constrains type 2 inflammation and humoral immune responses during microbial exposure. Ongoing studies will determine how Blimp-1 suppresses keratinocyte-derived TSLP production and whether identified compounds can restore epithelial immune homeostasis in atopic dermatitis models. Funding Source n/a Topic Categories Immediate Hypersensitivity, Asthma, and Allergic Responses (HYP)
Nrf2 suppresses inflammatory Th1/Th17 responses and promotes regulatory T cell differentiation by CD4+ T cells to alleviate ulcerative colitis 2260871
Abstract Introduction Ulcerative colitis (UC) is a chronic, relapsing form of inflammatory bowel disease (IBD) characterized by inflammation of the colon driven by an imbalance between proinflammatory and regulatory CD4+ T-cell subsets. Nrf2 (nuclear factor erythroid 2—related factor 2), a master regulator of oxidative stress responses, has emerged as a key modulator of immune cell function, but its role in regulating CD4+ T-cell differentiation and intestinal inflammation remains unclear. Methods To elucidate the role of Nrf2 in T-cell—mediated ulcerative colitis (UC), we used transgenic mice with T cell—specific deletion of Nrf2 (Nrf2-KO; no Nrf2) or Keap1 (Keap1-KO; high Nrf2). The effects of altered Nrf2 activity on CD4+ T-cell differentiation were examined using in vitro polarization assays, while disease outcomes were assessed using an adoptive transfer model of colitis, in which naïve CD4+ T cells from WT or Keap1-KO mice were transferred into immunodeficient Rag1⁻/⁻ mice. Single cell RNAseq data from the colons of UC patients was analyzed to identify gene signatures. Results CD4+ T cells with elevated Nrf2 activity (Keap1-KO) showed reduced differentiation into inflammatory Th1 and Th17 subsets and enhanced differentiation and function of Foxp3+ regulatory T cells (Tregs). In the adoptive transfer model, high Nrf2 activity in CD4+ T cells markedly alleviated colonic inflammation and reduced disease severity. Mechanistically, Nrf2 enhanced glutamine metabolism in induced Tregs, promoting oxidative phosphorylation and increased Foxp3 expression. Consistently, colonic CD4+ T cells from UC patients with higher Nrf2 expression exhibited lower inflammatory gene signatures. Conclusion These findings demonstrate that Nrf2 suppresses pathogenic Th1/Th17 responses while promoting regulatory T-cell differentiation and metabolic fitness, thereby alleviating colitis. T cell—intrinsic activation of Nrf2 represents a promising therapeutic strategy for treating UC and other inflammatory disorders of the gut. Funding Source This work was supported by startup funds by the University of Kansas Cancer Center (KUCC). We acknowledge the support and funds from Kansas Institute for Precision Medicine (NIGMS P20 GM130423). Topic Categories Lymphocyte Differentiation and Peripheral Maintenance (LYM)
Immune Checkpoint Activation Targeting PD-1H (VISTA) Reinforces Human T-Cell Tolerance in Autoimmunity 2335053
Abstract Introduction Immune checkpoints enforce tolerance, while their inhibition boosts antitumor immunity, autoimmunity may benefit from the opposite approach. Immune checkpoint activators (ICAs) offer a promising approach to restore tolerance without broad immunosuppression. PD-1H (VISTA/VSIR) is an inhibitory checkpoint on T cells and myeloid cells implicated in autoimmune regulation. Here, we investigate PD-1H activation as a strategy to suppress pathogenic T-cell responses and reinforce immune balance in autoimmunity. Methods We analyzed public single-cell RNA-seq datasets and performed flow cytometry of healthy and lupus PBMCs to assess PD-1H expression and clinical associations. An in vitro T-cell exhaustion model was employed, with PD-1H disrupted by CRISPR—Cas9. An agonistic human PD-1H monoclonal antibody (hPD-1H.ICA.1) was identified and evaluated in vitro and in vivo in humanized GvHD and lupus PDX models. Results PD-1H was upregulated on antigen-experienced T cells and sustained under chronic stimulation. PD-1H deficiency enhanced T-cell effector function and reduced PD-1+TIM-3+ exhausted subsets. Analysis of the public datasets revealed elevated PD-1H expression on renal-infiltrating T cells, exceeding other inhibitory checkpoints. Flow cytometry confirmed PD-1H+ T cells in lupus PBMCs, with expression correlating with disease activity. The hPD-1H.ICA.1 suppressed early T-cell activation, and under chronic stimulation reinforced an exhaustion-like program. In humanized GvHD models, hPD-1H.ICA.1 reduced disease severity. In lupus PDX models, hPD-1H.ICA.1 ameliorated renal pathology and selectively depleted pathogenic T-cell populations while enriching exhausted subsets. Conclusion Our findings identify PD-1H as a key checkpoint regulating chronic human T-cell responses and provide preclinical proof-of-concept that immune checkpoint activation can restore immune tolerance by enforcing exhaustion of pathogenic T cells, supporting PD-1H agonism as a promising therapeutic strategy for autoimmune disease. Funding Source This work was supported by startup funds from The Ohio State University Comprehensive Cancer Center and the College of Medicine, as well as funding from the Leukemia Research Foundation, the Cancer Research Institute, and the NIH. Topic Categories Immune Response Regulation: Cellular Mechanisms (IRC)
Single-Cell Atlas of Microglia Reveals Conserved and Divergent Cell Populations in Mouse and Human Brain 2255696
Abstract Introduction Microglia are resident immune cells in the central nervous system and a heterogenous population with notable heterogeneity across development phases, regions, and disease states. While a few ‘microglia’ single cell atlases have recently emerged to profile large microglia datasets, a comprehensive, single cell/nuclei-resolution map of microglial subtypes and functional or activation states across different species remains lacking, especially one that performs an integrative secondary analysis of existing data. Methods Here, we present a cross-species single-cell transcriptomic atlas of microglia from mouse and human brains, spanning multiple regions, sexes and ages. We use integrated analysis of single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics datasets and tackle computational challenges like batch effect and modality integration. Results Our dataset encompasses over 200,000 microglial cells from adult human postmortem brains and sex as well as age-matched murine counterparts. We benchmark several integration approaches using anchor-based and deep manifold alignment methods. Our secondary analysis reveals a core set of conserved microglial subtypes, including homeostatic microglia (TMEM119+, P2RY12+), interferon-responsive microglia (ISG15+, IFIT3+), and phagocytic/activated states (CD68+, APOE+, CST7+). Notably, we identify a conserved ‘lipid-associated microglia’ (LAM) state marked by high APOE, TREM2, and GPNMB expression in both species, enriched in aging and neurodegenerative conditions. Conclusion Our dataset collection, which is available via a web-interactive atlas tool, provides a valuable resource for understanding microglial diversity across species and lays the foundation for translating findings from mouse models to human. These findings support the existence of evolutionarily conserved microglial programs and highlight the need for caution when extrapolating mouse microglial states to human contexts. Funding Source NA Topic Categories Neuroimmunology (NEUR)
Investigating interferon lambda (IFN-γ) as a novel anti-inflammatory modulator of the skin barrier-immune-microbiome axis in atopic dermatitis 2309532
Abstract Introduction Atopic dermatitis (AD) is a chronic inflammatory skin disease driven by type 2 (Th2)-mediated immune dysregulation, epidermal barrier dysfunction and microbial dysbiosis. While current therapies suppress acute inflammation, they often fail to restore the coordinated barrier—immune—microbiome homeostasis underlying chronic disease persistence. Interferon lambda (IFN-γ), a type III interferon with epithelial-restricted receptor expression, has emerged as a potential multi-axis immunomodulator capable of enhancing barrier function, limiting Th2-associated immune activation and restricting pathogenic microbial overgrowth. However, its integrated effects have not been evaluated in vivo in AD. We hypothesized that topical IFN-γ treatment would restore skin homeostasis by attenuating Th2-driven inflammation. Methods An MC903-induced AD model was established in C57BL/6 mice receiving topical IFN-γ or vehicle control during disease induction. Disease severity was assessed longitudinally by standardized clinical scoring. Barrier integrity was evaluated by histological analysis and expression of barrier-associated genes. Th2-associated immune responses were assessed in lesions and draining lymph nodes using multiplex cytokine assays and flow cytometry. Cutaneous microbial composition was analyzed through 16S rRNA sequencing. Results Topical IFN-γ treatment reduced clinical disease severity and epidermal hyperplasia compared with controls. IFN-γ—treated mice exhibited decreased Th2-associated cytokine expression and reduced inflammatory immune cell infiltration. Microbiome analysis revealed reduced S. aureus abundance and increased microbial diversity in IFN-γ—treated groups, indicating partial restoration of microbial homeostasis. Conclusion These findings demonstrate that IFN-γ functions as an epithelial-targeted immunomodulator capable of improving barrier integrity, suppressing Th2-immune signalling and restoring microbial balance in AD, supporting its potential as a multi-target therapeutic strategy. Funding Source Canadian Institutes of Health Research (CIHR) Topic Categories Immediate Hypersensitivity, Asthma, and Allergic Responses (HYP)
Association Between Obesity and Asthma Severity: Analysis of NHANES Data 2021—2023 2309566
Abstract Introduction Obesity is a recognized risk factor for asthma severity, but comprehensive population-level data analyses are limited. Understanding these associations is critical for addressing gaps in immunologic research and clinical interventions. Methods National Health and Nutrition Examination Survey (NHANES) data from August 2021 through August 2023 was utilized to gather information regarding study participants with current asthma, as defined in the survey as responding “yes” to question MCQ035 “Still have asthma”. BMI categories were defined as normal (< 25 kg/m²), overweight (25—29.9 kg/m²), and obese (≥30 kg/m²). Severe asthma was defined as responding “yes” to either MCQ040 “Had asthma attack in past year” or MCQ050 “Emergency care visit for asthma/past yr”. Chi-square tests of independence were performed to evaluate differences of the rates of severe asthma across BMI categories. Results The total number of survey participants with current asthma was 927. Sample size per BMI category was 294 for normal-weight, 234 for overweight, and 399 for obese. Asthma attack prevalence was 50.0% (147/294) among normal-weight, 45.7% (107/234) among overweight, and 51.1% (204/399) among obese participants (χ² = 1.78, df = 2, p = 0.41). ED visit prevalence was 13.9% (41/294), 14.5% (34/234), and 12.3% (49/399) for normal-weight, overweight, and obese groups, respectively (χ² = 0.79, df = 2, p = 0.67). Although obese participants had the highest absolute number of asthma attacks, differences across BMI categories were not statistically significant. Conclusion Asthma attacks and emergency care visits for asthma were prevalent across all BMI categories, highlighting a substantial asthma burden of regardless of BMI. These findings underscore the need for further studies to elucidate the association between obesity and asthma severity across the lifespan and to explore underlying immunologic mechanisms that may help develop more tailored asthma management plans. Funding Source n/a Topic Categories Immediate Hypersensitivity, Asthma, and Allergic Responses (HYP)
Integrated Electrode‐to‐Device Design via Combination of Grain Boundary Reconstruction and Dynamic Gas Management Toward Stable 3 Ah Aqueous Zinc‐Iodine Pouch Cells
ABSTRACT The substantial electrochemical performance gap between Ah‐level pouch cells and laboratory‐scale coin cells remains a critical bottleneck hindering the practical application of aqueous Zn‐I 2 batteries. Herein, Zn anode degradation and cell‐level gas accumulation, exacerbated under large‐area‐electrode conditions, are systematically identified as dominant failure mechanisms in high‐capacity Zn‐I 2 pouch cells. Accordingly, an integrated electrode‐to‐device strategy is proposed, combining Zn grain‐boundary reconstruction with dynamic gas management. The intrinsically nonuniform grain boundary distribution in commercial zinc foil is confirmed to induce stripping heterogeneity and subsequent dendrite growth, while persistent H 2 evolution leads to cell swelling and electrolyte leakage, ultimately resulting in accelerated capacity fading. At the electrode level, a scalable electrodeposition strategy yields current‐collector‐integrated zinc anodes with refined grains and homogenized boundaries, effectively mitigating initial stripping heterogeneity and enhancing zinc utilization. At the device level, a selective H 2 ‐expulsion window (LaNi‐based hydrogen storage alloy nanoparticles embedded in a hydrophobic PTFE matrix) is integrated into the aluminum‐plastic packaging, enabling efficient H 2 removal while blocking water vapor to maintain electrolyte stability. Leveraging this design, multilayer‐stacked Zn‐I 2 pouch cells with >3 Ah capacity and an ultra‐low N/P ratio of 1.18 achieve over 600 stable cycles. This work offers a scalable, system‐level solution toward practical aqueous Zn‐based pouch cells.
Polymorph‐Specific Electronic Transduction in WO <sub>3</sub> during Molecular Sensing
ABSTRACT Polymorphs are distinct structural forms of the same compound and offer unique opportunities to tailor material properties without altering chemical composition. In particular, the polymorphs of WO 3 have been widely explored for their molecular sensing performance; yet, the mechanistic aspects behind their different chemoresistive properties have remained elusive or poorly understood. Here, we highlight the energetic allocation of transferred charge as a critical aspect for chemoresistive response generation, providing a new perspective beyond more conventional net‐transfer metrics, which are usually deployed to investigate gas–solid interactions. To this, we combined operando work function, chemisorption analysis, and in situ spectroscopy with density functional theory calculations on the example of acetone. Both γ ‐ and ε ‐WO 3 exhibit comparable surface‐level activation of acetone, mediated by electron‐deficient, coordinatively unsaturated tungsten sites. However, only ε ‐WO 3 stabilizes analyte‐induced electronic states derived from W(5d) orbitals lying just below the conduction band—an energetically favorable region for conductivity modulation under operating conditions. While being associated with marginal work function shifts, these states reflect deeper subsurface electronic rearrangements that may underlie the ε ‐WO 3 ’s superior transduction efficiency despite similar receptor chemistry. Our results offer a new framework for rational transducer development rooted in intrinsic electronic structure.
Neuroinflammatory Responses in Glial-Immune Interactions to Francisella tularensis in the Central Nervous System microenvironment 2267481
Abstract Introduction Francisella tularensis (Ft), the causative agent of tularemia, is a highly infectious intracellular pathogen and recognized Tier 1 Select Agent due to its low infectious dose, multiple routes of transmission, and potential use in bioterrorism. While Ft’s role in systemic inflammation is well established, its impact on the central nervous system (CNS) and its interaction with brain-resident immune cells is unknown. Methods This study investigates the neuroinflammatory response of glial and immune cells to Ft infection using an in vitro co-culture model that mimics the CNS microenvironment. Specifically, this study explores how Ft affects the inflammatory behavior of microglia, astrocytes, and macrophages individually and in combination following Ft infection and through the quantification of inflammatory cytokine production, thus characterizing glial-immune responses, and identifying mechanisms by which Ft may disrupt CNS homeostasis. Results Our findings suggest that Ft infection induces strong pro-inflammatory signaling among CNS-resident cells and emphasizes the importance of using multicellular models to study neuroimmune responses to infection. Notably, astrocytes influence microglial and macrophage immune responses through the release of soluble factors. This paracrine communication enhances cytokine production and inflammatory activation in these immune cells without direct cell contact, contributing to amplified neuroinflammation. Conclusion This work provides foundational insight into Ft-mediated neuroinflammation and supports further investigation into mechanisms of blood-brain barrier (BBB) disruption and bacterial persistence within the CNS. Insights from this model may inform future strategies to mitigate Ft-induced neurological damage and guide development of targeted therapeutics. Funding Source n/a Topic Categories Innate Immune Responses and Host Defense: Cellular Mechanisms (INC)
NKG2D Supports Long Lived Effector T Cell Function 2308628
Abstract Introduction Memory CD8 T cells display heterogeneity in their phenotype and function. We have described a memory subset of CD8 T cells termed Long Lived Effector T cells (LLECs) that maintain high expression of KLRG1. LLECs maintain strong effector function and are more effective at clearing systemic infections than other memory subsets. LLECs are enriched for the expression of Natural Killer (NK) receptors on their surface compared to other memory T cells. These receptors on NK cells are classified as either activating or inhibitory, but their role on CD8 T cells has not been extensively investigated. NKG2D is highly expressed on LLECs and is an activating receptor that recognizes stress ligands. We hypothesize that the expression of activating NK receptors increases the cytotoxic capacity of LLECs in both an antigen specific manner by acting as a costimulatory receptor and allows them to respond to bystander cues in the absence of T cell receptor stimulation. Methods To address the role of NKG2D as a costimulatory molecule, we have leveraged OT-I and P14 CD8 T cells activated with cognate peptide, Ova and Gp33, respectively. We used CRISPR to ablate NKG2D on naïve T cells and blocking antibodies against NKG2D to investigate differences in response when NKG2D signals are lost. We have also utilized the “dirty mouse” model of normalized polymicrobial exposure (NME) to study the role of NKG2D in bystander responses mediated by a polyclonal memory pool. Results Our preliminary work has found that interruption of NKG2D signaling leads to reduced T cell polyfunctionality following peptide stimulation. Additionally, we find that blocking NKG2D in a NME reduced the ability of mice to clear a novel Listeria monocytogenes infection. Conclusion This work supports that NK receptors contribute to CD8 T cell responses and pathogen clearance and may be particularly relevant on LLECs as a regulator of their robust effector function. Funding Source R01AI155468 Topic Categories Immune Response Regulation: Cellular Mechanisms (IRC)
Non-Invasive Theranostics for Endometriosis 2259283
Abstract Introduction Endometriosis (EM) presents significant clinical challenges due to associated pain, infertility, presentation and pathophysiology. There is an urgent unmet need for improved diagnostics and therapeutic approaches to EM. Here, we report the identification of EvA1C as a potential biomarker displayed on the luminal surface of endothelial cells (ECs) in EM lesions. Targeting of EVA1C by engineered nanobodies (NAbs) could have therapeutic and/or diagnostic utility. Methods Public single-cell RNAseq data of human EM were analyzed bioinformatically and compared to a comprehensive atlas of transcriptional profiles of EC from 20 normal tissues. EvA1C mRNA was robustly expressed in ECs in EM, but not in other tissues, including uterus. We screened a yeast display library of camelid NAbs to isolate clones against the EvA1C ectodomain. By alternating between human and murine EVA1C as a bait followed by a single cell sorting, we screened for NAbs recognizing EVA1C in both species. Candidate subclones were expressed in E. coli and assessed for their antigen binding properties by ELISA, flow cytometry and confocal microscopy. Results NAb clones were identified that recognize the ectodomain of human and mouse EVA1C with similar binding affinity. Immunohistochemistry confirmed at the protein level preferential endothelial EvA1C expression in ectopic EM lesions but not in eutopic endometrium. Further experiments will assess the utility of anti-EvA1C NAbs for non-invasive diagnosis and therapy of EM. Conclusion We developed NAbs that recognize EVA1C, a candidate microvascular target in EM. In vivo imaging of EvA1C expression after IV injection of NAbs carrying a radiotracer or contrast agent may be useful as a biomarker to enable the diagnosis, localization and monitoring of EM by routine medical imaging. Ultimately, NAb mediated targeting of endothelial EVA1C may also allow delivery of a therapeutic payload to reduce or ablate EM lesions. Funding Source Q-FASTR Pilot grant Topic Categories Immune Mechanisms of Human Disease (HUM)
Mechanism of Gzma-Mediated GEF-H1 Activation in Intestinal Epithelial Cells Leading to Intestinal Barrier Dysfunction in Sepsis 2254641
Abstract Introduction This study investigates how Granzyme A (GZMA) induces intestinal barrier dysfunction in sepsis, specifically by activating the GEF-H1—RhoA signaling axis. It aims to elucidate the underlying molecular mechanisms and evaluate the therapeutic potential of targeting GZMA and GEF-H1 for sepsis. Methods 1.A cecal ligation and puncture (CLP) mouse model of sepsis was established. qPCR, HE staining, and IF assessed GZMA upregulation, inflammatory cytokine levels, organ damage, and intestinal barrier integrity (via ZO-1/E-cadherin). 2.Intestinal epithelial cells were co-cultured with LPS-stimulated NK92MI cells or treated with recombinant GZMA. Barrier function was evaluated by TEER, permeability assays, and IF for tight junction proteins. 3.Western blot and qPCR analyzed GEF-H1—RhoA pathway components (RhoA, LIMK1, MLC2, cofilin). GEF-H1’s role was confirmed using siRNA knockdown/overexpression in cells and GEF-H1-/- septic mice. Results 1. Sepsis models showed significantly increased GZMA expression and concurrent disruption of the intestinal epithelial barrier. 2.GZMA directly increased intestinal epithelial permeability. Co-culture with LPS-stimulated NK92MI cells or direct GZMA treatment impaired barrier function in vitro. 3.GZMA activated the GEF-H1/RhoA signaling pathway in multiple intestinal epithelial cell lines under septic conditions. 4.Inhibiting GEF-H1 (via KO in mice or siRNA in cells) alleviated intestinal barrier injury, improved survival, and suppressed GEF-H1/RhoA pathway activity. 5.Overexpression or stabilization of GEF-H1 exacerbated epithelial barrier damage in sepsis models. Conclusion GZMA is upregulated in sepsis and disrupts intestinal barrier integrity. The mechanism involves GZMA promoting GEF-H1 phosphorylation, which activates the RhoA—ROCK—MLC2 pathway, leading to dysregulation of tight junction proteins (occludin, claudin-1, ZO-1) and increased permeability. GZMA and GEF-H1 represent promising therapeutic targets for sepsis-induced intestinal barrier dysfunction. Funding Source National Natural Science Foundation of China (82272209) Topic Categories Cellular Adhesion, Migration, and Inflammation (CAM)