Browse Articles

Surface Reconstruction‐Integrated Bulk Defect Engineering Beyond Conventional Chemical Modulation for Na‐Layered Oxide Cathodes

ABSTRACT As the most prospective cathode material for sodium‐ion batteries (SIBs), layered oxides persistently suffer from detrimental phase transitions, irreversible oxygen loss, and severe interfacial degradation during cycling. Herein, utilizing O3‐NaNi 1/3 Fe 1/3 Mn 1/3 O 2 cathode as prototype, we propose an integrated modification strategy beyond conventional chemical modulation to simultaneously boost the bulk, surface and interfacial properties. The Y‐enriched NaYO 2 (NYO) coating derived via surface reconstruction facilitates site‐selective bulk substitution whilst inducing suitably quantized local oxygen vacancy (O V ) defects through charge balancing. The synergistic interaction between Y─O─TM strong bond and the O V 's charge‐buffering effect jointly modulates O 2p orbital electronic band configuration, preventing excessive O oxidation and formation of O─O dimers arising from charge concentration. Moreover, the perovskite‐phase NYO surface serves as an inherent fast Na + conductor ensuring efficient ion transport at interface, whilst also providing a robust rigid mechanical barrier that effectively suppresses interfacial side reactions and dissolution of transition metals. As a result, anion redox reversibility and local chemical environment stability are elevated, thereby comprehensively boosting electrochemical reaction kinetics and charge transfer efficiency, as confirmed by theoretical calculations and advanced synchrotron characterization. This research establishes a novel paradigm for the advancement of high‐performance Na‐layered oxide cathodes incorporating synergistic multi‐mechanism modification.

Establishing leukocyte reference values in seven wild-caught shark species 2259588

Abstract Introduction Immune assessment in wildlife populations is challenging. Peripheral blood sampling is a non-invasive approach in understudied elasmobranch populations. However, hematological reference values are scarce for most shark species, limiting veterinary and conservation applications. This study establishes reference intervals for differential leukocyte counts across seven wild-caught shark species. Methods Peripheral blood smears from Carcharhinus limbatus (blacktip), C. acronotus (blacknose), C. plumbeus (sandbar), C. leucas (bull), C. perezi (Caribbean reef), Negaprion brevirostris (lemon), and Galeocerdo cuvier (tiger) were analyzed. Wright—Giemsa—stained leukocytes were classified morphologically as lymphocytes, neutrophils, coarse eosinophilic granulocytes (CEG), fine eosinophilic granulocytes (FEG), monocytes, and basophils. Counts were conducted (100 cells/slide) in triplicate per individual, and morphometric measurements were conducted using image analysis software. Results Leukocyte profiles varied across species and were dominated by lymphocytes with consistently low monocyte and basophil frequencies. Granulocyte to lymphocyte (GLR) ratios were within a narrow range, supporting GLR as a useful hematological biomarker. Substantial differences in granulocyte morphology were observed even among closely related species. C. limbatus exhibited lymphocyte predominance with balanced granulocyte subtypes. N. brevirostris showed comparatively few immature cells. Some species (C. leucas and G. cuvier) displayed elevated granulocyte ratios, which may be important considerations in evaluating immunological responsiveness to environmental stressors. Conclusion This study presents the first leukocyte reference intervals established from multiple species of wild-caught sharks. Results reveal interspecific variability in leukocyte distribution and establish essential hematological baselines for health assessment and conservation monitoring. Funding Source This research was supported by the University of Miami (UM) Shark Research and Conservation Program and the Disney Wildlife Conservation Fund; no other funding sources were involved. Topic Categories Veterinary and Comparative Immunology (VET)

The immunomodulatory potential of a medicinal plant-derived exosome-like nanovesicles and their applications in inflammatory skin disorders 2258926

Abstract Introduction Chronic immune-mediated skin disorders such as psoriasis and atopic dermatitis are characterized by epidermal hyperproliferation, barrier dysfunction, and cytokine-driven inflammation. Dysregulated production of proinflammatory cytokines perpetuates keratinocyte and immune cell activation. Current therapies, including biologics, are accompanied by side effects, which necessitate safer, more accessible, and non-immunosuppressive alternatives. Plant-derived exosome-like nanovesicles (PDENs) are emerging as biocompatible nanotherapeutics with the capacity to serve as immunomodulatory natural delivery vehicles. This project aimed to explore the immunomodulatory potential of PDENs derived from Dendrobium fimbriatum Hook (DF) stems, a traditional Chinese medicinal herb, in suppressing inflammatory responses in immune-mediated skin diseases. Methods PDENs were isolated from DF stems via differential ultracentrifugation and sucrose-density gradient ultracentrifugation (DF-PDENs). Nanoparticle tracking analysis was used to evaluate size distribution and particle yield. Human keratinocyte models were stimulated with TNF-α and IL-17 to simulate skin inflammation, and murine T-cell models were stimulated with IL-17 and IFN-γ to investigate molecular mechanisms and pathways. Cytokine secretion (IL-6, IL-8) was measured via ELISA, and Western blotting was used to elucidate the intersection with key molecular inflammation pathways. Results DF-PDENs exhibited high purity and stability, as confirmed by nanoparticle tracking analysis. Treatment with DF-PDENs significantly reduced IL-6 and IL-8 production in TNF-α- and IL-17-stimulated keratinocytes. Preliminary signalling analyses revealed attenuation of inflammation-associated molecular pathways. Conclusion DF-PDENs demonstrated anti-inflammatory activity in vitro, supporting their potential as a novel nanotherapeutic for treating immune-mediated skin diseases, such as psoriasis. Funding Source Chinese Medicine Research Center of China Medical University, under The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project Yu Shan Fellow Program by the Ministry of Education, Taiwan. Topic Categories Translational and Interventional Immunology (TI)

Changes in genes in the TLR signaling pathway within the lumbar spinal cord of doxycycline-inducible Tat transgenic mice following Tat induction 2254518

Abstract Introduction A common complication of human immunodeficiency virus (HIV)-1 infection is HIV neuropathy, which is often associated with poorly managed pain. The toll-like receptor (TLR) pathway is known to be involved in neuropathic pain, but its role in painful HIV neuropathy has not been investigated extensively. Tat, trans-activator of transcription, is a viral regulatory protein expressed early during HIV infection and is a key activator of HIV transcription. Following Tat induction, the glial fibrillary acidic protein (GFAP)-driven, doxycycline-inducible HIV-1 Tat transgenic (iTat) mice display neuropathy-like behaviors. A panel of approximately 200 inflammation-related genes were measured in the lumbar spinal cord of iTat mice following Tat induction via NanoString® technologies. Bioinformatic analysis identified the regulation of Tat of the TLR signaling pathway. Methods In this current study, we further examined the temporal changes of TLR-related genes within the NanoString profiling data to explore the potential involvement of TLR-mediated pathways. Genes encoding TLRs 1-9, major TLR pathway related signaling molecules, type 1 interferons, as well as the interferon-inducible proteins, were analyzed. Tat induction was achieved by treating iTat mice daily with doxycycline from days 0-13. Results We observed that of all the TLRs, TLR3 showed a significant upregulation starting from day 21, while upregulation of both TLRs2, 4 and 9 were slight and/or transient. Transient upregulation of type I interferon genes, as well as several interferon-inducible proteins, such as Ifi44, Ifit1/3, Mx1, and Oas1a, was also noted. No significant sex differences were noted for any of the genes examined. Conclusion Our results indicate an overall upregulation of TLR-mediated type I interferon responses following Tat induction. Ongoing study will determine if these changes are reflected at protein levels. The role of Type I interferon response in Tat-associated neuropathy will be further investigated in the future. Funding Source NIH/NIDA 1R21DA044886 (Cao) and NIH/NINDS 1R01NS132674 (PI Cao) Topic Categories Immune Mechanisms of Human Disease (HUM)

Epigenetic and lineage-specific transcription factors regulate the cell type specific induction of type I and type III interferons 2307867

Abstract Introduction Viral respiratory and mucosal infections affect millions of people in the USA and worldwide, creating a serious health burden. The body defends against these viruses using two main types of interferons: type I (IFN-I) and type III (IFN-III). Both types are activated by the same sensors in our cells. Different cell types make them at different times: pDCs produce IFN-I within 3-6 hours, whereas epithelial cells make IFN-III at ∼24-48 h with little IFN-I. Our early work suggests that turning on the right interferon quickly depends on how each cell type arranges its DNA, keeping some genes ready and others silent. This work aims to understand how unique combinations of chromatin landscape and transcription factors in each cell type sets this genetic context. Methods We studied interferon induction in primary human pDCs and the CAL-1 line, hepatocytes, and human intestinal organoids. After viral PAMP stimulation, we measured IFN-I/III transcripts by qPCR, chromatin was mapped by time-resolved ATAC-seq and CUT&RUN for IRF8, PU.1, RNA polymerase II (Ser5P, Ser2P), and histone marks (H3K27ac, H3K4me1/3, H3K27me3, H3K36me3, H3K9me3). Results pDCs produced IFN-I early; epithelial models produced mostly IFN-III with little IFN-I. ATAC-seq and Pol II (Ser5P, Ser2P) showed open chromatin, promoter engagement, and elongation at IFN-I loci in pDCs, but closed chromatin and weak polymerase at IFN-III. The opposite pattern was seen in epithelial cells. PH5CH8 cells and human gut organoids which shared the epithelial signature: higher baseline accessibility and stimulus-induced RNA polymerase binding at IFN-III and relative inactivity at IFN-I. Conclusion PU.1/IRF8 favors early IFN-I induction in pDCs; HNF4A/FOXA favors delayed IFN-III in epithelia. These understandings can help to devise chromatin-focused ways to boost IFN-III while limiting IFN-I-driven inflammation. Funding Source ITHS grants Topic Categories Innate Immune Responses and Host Defense: Cellular Mechanisms (INC)

Immune checkpoint blockade enhances CD4 effector function to control persistent viral infection 2267612

Abstract Introduction T cell exhaustion, a defining hallmark of chronic viral infections and cancer, is characterized by the progressive loss of effector function and sustained expression of inhibitory receptors on T cells. Although immune checkpoint blockade (ICB) therapies, such as PD-1 inhibition, can transiently reinvigorate subsets of exhausted CD8+ T cells, their efficacy remains constrained by the limited pool of self-renewing, progenitor-like TCF1+ CXCR5+ CD8+ T cells. We have previously demonstrated that B cell—derived IL-27 signaling is necessary for the expansion and maintenance of this progenitor-like population during chronic infection. Using an IL-27 receptor deficient mouse model, we reveal a previously unrecognized mechanism by which PD-1 blockade mediates viral clearance. We demonstrate that PD-1 inhibition enhances CD4+ T cell function, specifically through increased IL-21 production from T follicular helper (Tfh) cells which promotes both humoral and cytotoxic antiviral responses. Our findings identify a novel IL-27 independent CD4+ T cell axis through which checkpoint blockade controls persistent viremia. Methods To determine the impact of checkpoint inhibition on persistent viral infection, IL-27 receptor—deficient mice were infected with chronic lymphocytic choriomeningitis virus (LCMV clone 13) and treated with PD-1 blocking antibodies. We used flow cytometry and viral titers to evaluate CD4+ and CD8+ T cell subsets, the importance of IL-21, and persistent viral clearance. Results PD-1 blockade restored antiviral immunity in IL-27 receptor—deficient mice and resulted in enhanced CD4+ T cell function. We saw increased IL-21 production from T follicular helper cells that led to higher cytotoxic and humoral antiviral responses. Conclusion Our studies reveal that PD-1 blockade can drive persistent viral clearance through an IL-27—independent mechanism that involves IL-21—producing CD4+ T cells. Funding Source N/A Topic Categories Viral Immunology (VIR)

Activation, localization, and autoantibody production of tissue-based age-associated B cells in human type 1 diabetes 2257444

Abstract Introduction T cells mediate type 1 diabetes (T1D) pathogenesis, but mouse studies indicate that B cells function as critical antigen presenters. The specific B cells that contribute to disease in humans are poorly defined because studies typically sample blood. Methods We profiled B cells and their antibody genes in lymphoid tissues (spleen, pancreatic and mesenteric lymph nodes) of T1D organ donors (n = 23) and controls (n = 19) from the Human Pancreas Analysis Program. We performed phenotyping, single cell RNA sequencing, antibody gene sequencing, and in vitro stimulation to identify B cell signatures associated with T1D. Results We observed an increase in age-associated B cells (ABCs; IgD-IgM-CD21-CD11c+Tbet+) in multiple lymphoid tissues during T1D, most strikingly in male spleen. RNA sequencing of sorted ABCs from spleens of 7 age- and sex-matched T1D/control pairs identified T1D-associated transcriptional changes: T1D ABCs upregulated genes including LAIR2, ROR1, and RAMP1 and downregulated MYC and EGR3. TNFRSF1B (TNF receptor 2) and downstream signaling components were upregulated in a subset of ABCs in T1D males, consistent with increased cell activation and survival. Stimulated ABCs from T1D donors also harbored reactivity to T1D-associated autoantigens (insulin, IA-2, GAD65). Antibody clone tracking revealed clonal sharing between splenic ABCs and multiple antigen-experienced B cell subsets in pancreatic lymph nodes (pLN), suggesting these pLN clones may originate in spleen. Monoclonal antibodies generated from these shared pLN/spleen ABC clonal lineages demonstrated both T1D autoantigen binding and multireactivity. Conclusion These findings support a novel role for ABCs in T1D. Our data suggest that expanded autoreactive ABC reservoirs in spleen can seed effector B cell populations in pLN, where T1D autoimmune responses likely occur. These findings identify new mechanisms for the contribution of tissue-based B cells to T1D pathogenesis and have implications for B cell therapeutic targeting. Funding Source Funding was provided by HPAP NIDDK 2U01-DK112217 Topic Categories Basic Autoimmunity (BA)

Phagocytic CD206+ interstitial macrophages are remodeled after pneumococcal respiratory infection 2257592

Abstract Introduction Innate immune memory of lung macrophages is a crucial host safeguard against repeated respiratory infections. Based on the tissue compartments, there are alveolar macrophages and interstitial macrophages (IMs). IMs are further subdivided into CD206- and CD206+ subpopulations that have distinct localizations, transcriptomes, and functions. Whether IM subpopulations have the capacity to remodel after repeated infections is unknown. Methods Ontogeny of IMs was determined using Flk/switch reporter mice, whereby embryonic cells express tdTomato and bone marrow derived cells express GFP. Mice had left lobe intratracheal instillations of pneumococcus (“Experienced”) or saline (“Naïve”) at days 0 and 7. At day 35, IMs were studied using flow cytometry. Differences in localization were determined through mfIHC in Cx3cr1+/GFP reporter mice. IM recruitment was tested in B- and T-cell depleted mice (using cell-depleting antibodies against CD20 and CD4, respectively) and CCR2-/- mice. Transcriptomic analysis of lung macrophages was carried out by CITE scRNA-sequencing using surface protein markers to differentiate IM subsets. Phagocytic activity of IMs was determined by instilling fluorescent pneumococcus or E. coli Results The majority of IMs in the naïve lung are primarily bone marrow derived. Following repeated pneumococcus infections, both CD206- and CD206+ IMs were more abundant in experienced lungs compared to naïve lungs. Immunohistological staining showed IMs become the predominant lung macrophage in experienced mice. CD206+ IM recruitment was dependent on a second infection, and independent of B and T lymphocytes as well as CCR2. Only CD206+ IMs showed remodeled surface marker expression, transcriptome, and phagocytic capacity. Conclusion CD206+ IMs are phenotypically and functionally remolded after infection. Future mechanistic studies will evaluate how the enhanced phagocytic phenotype impacts host defense. Funding Source R01 Al115053, R35 HL135756, F31 HL178234 Topic Categories Innate Immune Responses and Host Defense: Cellular Mechanisms (INC)

T cell mediated dysregulation of bone marrow hematopoiesis in Glioblastoma 2260498

Abstract Introduction Glioblastoma (GBM) is an aggressive brain cancer which induces severe systemic immunosuppression. Systemically, immune organs including the thymus and spleen involute, severe T cell lymphopenia occurs, and significant numbers of T cells are sequestrated within the bone marrow. The mechanisms underlying and linking local and systemic immunosuppression remain poorly understood. In particular, mechanisms governing T cell sequestration in the bone marrow of glioma-bearing subjects is understudied. Methods We evaluated the brain-bone marrow axis in GBM. Results One possible mechanism linking the TME to systemic immune derangements is the process of hematopoiesis in the bone marrow. Hematopoiesis results in generation of immune cells from hematopoietic stem and progenitor cells (HSPCs). Given that significant numbers of T cells are sequestrated in this delicate niche in glioma-bearing subjects, it is possible that their presence is troublesome. We seek to understand how T cell sequestration affects bone marrow function. To induce T cell sequestration, gliomas may impact the immune system either though release of soluble factors or via innervation. To distinguish between these possibilities, we employed parabiosis which is the surgical joining of two mice. When linking the circulation of GBM-bearing and tumor-naïve mice, we found that T cell sequestration occurred only in the bone marrow of GBM-bearing parabionts. This implicates innervation as an upstream mediator of T cell sequestration. Our preliminary data also demonstrate that the sequestrated T cells within the bone marrow of glioma-bearing mice directly impact HSPC numbers. Moreover, we connect the role of neutrophils and the brain-bone marrow innervation as upstream regulators of T cell sequestration into the bone marrow of GBM-bearing mice. Conclusion Our studies will shed light on novel mechanisms of brain-bone marrow communication and identify targets that can be leveraged to improve both local and systemic immunity in GBM. Funding Source NIH K99/R00 Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)

Antioxidant Proline Carbon Dot‐Composited Poly(L‐methionine) Hydrogel Restores Mitophagy to Alleviate Cellular Senescence in Intervertebral Disc Degeneration (Adv. Mater. 46/2026)

Neural Network Enabled Real‐Time Plasma Imaging for Inverse Designed Fabrication of Micro/Nano Structures with Ultrafast Laser

ABSTRACT Real‐time monitoring is essential for quality control in highprecision micro/nano structure fabrication with ultrafast laser. The laser‐induced plasma plume blocks the sample surface, preventing direct imaging of micro/nano structures during processing. This work proposes a neural networkenabled real‐time plasma imaging strategy and inverse design micro/nano fabrication method. The neural networks contain a conditional generative adversarial network (cGAN) for real‐time imaging and a multilayer perceptron (MLP) for inverse‐designed fabrication. Based on the fabrication of coffee‐ring feature structures, the cGAN generates high‐fidelity feature structure images from plasma intensity profiles, with a real‐time imaging latency of 1691 milliseconds. To validate the real‐time imaging strategy, dual‐pulse processing and sequential single‐pulse processing experiments are conducted across different materials. The MLP model establishes nonlinear relationships between laser parameters and feature structure size for inverse‐designed fabrication. Both forward prediction and inverse design results achieved a coefficient of determination (R 2 ) of 0.97, and the actual fabrication results align with the target values. This work provides a neural networkenabled strategy for real‐time process monitoring, advancing the development of intelligent laser fabrication.

Divergent roles for TLR7 and TLR9 in modulating the NFkB pathway in B cells 2261147

Abstract Introduction BCR signal strength plays a key role in the fate decision of B cells with strong BCR signals promoting plasma cell differentiation and weaker BCR signals driving germinal center formation. Signals through toll-like receptors (TLRs) also influence B cell differentiation. It is still unclear how the BCR and TLR signaling cascades interface to modulate B cell responses and differentiation. Using the BCR sdTg mouse model AM14 we reported earlier that BCR/TLR7-activated AM14 B cells differentiate into short-lived plasmablasts while plasma cell development does not occur in BCR/TLR9-activated AM14 B cells. Methods To better understand the signaling differences in BCR/TLR7 and BCR/TLR9 activated B cells, we activated purified AM14 B cells with RNA and DNA containing immune complexes and measured the activation of NFkB by Western blot analysis. We measured IkBz and BATF expression in these B cells at different timepoints by RT-PCR and Western blot. Furthermore, B cells from IkBz-deficient and BATF-deficient mice were activated with immune complexes and plasmablast differentiation was measure after 72 hours by flow cytometry. Results Intriguingly, we now show that BCR/TLR9 activation induces a more pronounced NFkB signal and the expression of the non-classical IkB member IkBz. BCR/TLR7-activated AM14 B cells are unable to sustain the initial NFkB response and fail to express IkBz. IkBz is known to be important in regulating cytokine responses in T cells and macrophages. However, its role in B cells is not well defined. We find that several IkBz regulated cytokines are expressed after BCR/TLR9 dependent signaling but not after BCR/TLR7 dependent signaling. Furthermore, we show that expression of IkBz inhibits plasma cell formation by regulating the expression of the transcription factor BATF. Conclusion Our results point to divergent roles for TLR7 and TLR9 in modulating the NFkB signaling cascades, leading to differential expression of NFkB target genes which influence B cell fate decisions. Funding Source LRA Target Identification in Lupus 2016 (KN), NIH 1R21AR076007-01A1 (KN) Topic Categories Lymphocyte Differentiation and Peripheral Maintenance (LYM)

The Invisible Influence: Microbial Dynamics Impacting Tumor Immunity in NSCLC 2259273

Abstract Introduction Lung cancer remains a leading cause of cancer mortality, with non-small cell lung carcinoma (NSCLC) comprising over 80% of cases. While immunotherapies have improved survival, challenges persist in overcoming tumor-driven immunosuppression and sustaining effective immune activation. Emerging evidence suggests the lung microbiome may influence these immune processes, yet its role in shaping NSCLC progression remains poorly defined. Methods Three human lung microbiome datasets were analyzed to identify microbial features of NSCLC, controlling for tissue type, therapy, smoking, and antibiotic use. Reads were processed with DADA2 and annotated via KEGG and MetaCyc. Two murine models were used: a K-Ras mutant model induced by intratracheal Cre recombinase, and xenografts (KP-NINJA, KP-HELLO) expressing neoantigens to recruit immune subsets. Mice were exposed intratracheally to heat-inactivated Burkholderia (health-associated), Veillonella dispar (disease-associated), or Klebsiella LPS (control). Results Human NSCLC tissues showed significantly reduced microbial diversity and metabolic activity, indicating a loss of microbial integrity with disease. In mice, immunotherapy preserved microbial diversity and structure in proportion to tumor regression, while neoantigen-expressing tumors that promoted immune infiltration similarly restored microbial balance. Direct administration of health-associated microbes enhanced immune cell infiltration and reduced tumor burden, whereas disease-associated microbes suppressed immune engagement and promoted tumor persistence. Spatial mapping revealed microbial byproducts colocalized with innate immune cells, supporting their role in amplifying anti-tumor immunity through local signaling networks. Conclusion These findings uncover a dynamic interplay between lung microbes and tumor immunity. Modulating microbial composition can reshape immune responses, presenting a novel strategy to improve NSCLC immunotherapy outcomes. Funding Source NIH T32 Brown Respiratory Research Training Program, NHLBI R01HL126887, NIH/NIEHS 5T32ES007272-24 Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)

Stimulating the resolution of inflammation overcomes CD8+ T cell exhaustion and boosts immunotherapy 2255409

Abstract Introduction PD-1 inhibition has revolutionized cancer therapy. However, despite the initial success of immune checkpoint inhibitors (ICIs) across several cancer types, this approach remains ineffective for most patients. Studies indicate that T cell exhaustion (Tex) is epigenetically encoded, and PD-1 blockade can only partially restore T cell activity. Chronic, non-resolving inflammation fosters an immunosuppressive tumor microenvironment (TME) that promotes T cell exhaustion and contributes to immunotherapy resistance. Our goal is to promote the resolution of inflammation through the administration of D-series resolvins (RvDs) to restore leukocyte antitumor activity and reverse immunosuppression and immunotherapy resistance within the TME. Methods We employed in vitro and in vivo models of HPV-positive head and neck cancer (HNC). Activated CD8+ T cells, isolated from human peripheral blood, were co-cultured with either tumor cell lines or primary tumor cells derived from patient biopsies. Cultures were stimulated with RvD5, a pro-resolving lipid mediator that promotes the resolution of inflammation. Syngeneic and NGS mouse models were treated with RvD5, anti-PD-1, and/or anti-CTLA-4 immunotherapies. Samples were analyzed by flow cytometry, cytokine profiling, lipidomics, bulk RNA sequencing, and single-cell RNA sequencing. Results We found that RvD5 reduced PD-1 expression on T cells and PD-L1 expression on cancer cells, thereby restoring T cell antitumor functions by delaying their differentiation into Tex. In vivo, RvD5 inhibited tumor growth. Notably, when combined with anti-PD-1 therapy, RvD5 enhanced tumor response rates, suggesting that shifting cancer-associated inflammation toward resolution can improve ICI efficacy. Conclusion Thus, RvD5 suppresses tumor growth by dampening inflammation and delaying T cell exhaustion within the TME. By reshaping CD8+ T cell responses, RvDs may represent a promising therapeutic strategy to strengthen antitumor immunity and overcome resistance to immunotherapy. Funding Source AIRC (MFAG 2022 — ID. 27060) Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)

Investigating features of dengue immunity that drive enhancement versus protection 2307730

Abstract Introduction Secondary dengue virus (DENV) infection can lead to severe disease through antibody-dependent enhancement (ADE). However, after recovery, individuals develop broad immunity to all four DENV serotypes, DENV1-4. Methods To investigate the features of natural DENV immunity that drive enhancement versus protection, we evaluated 45 adults who were flavivirus naïve or previously DENV exposed and challenged them with a live DENV3 vaccine (NCT05691530). We measured baseline antibodies using binding and function assays and DENV-specific T cells to evaluate their association with viremia. Results To identify the determinants of viremia, regardless of infection history, we grouped immune participants based on the area under the curve of their viremia using unbiased clustering: those with low viremia had no boost in neutralizing antibodies, consistent with sterilizing immunity (N = 8). Intermediate viremia was of similar magnitude to naïve participants (N = 12), and high viremia was significantly greater than in other groups, as observed during enhanced dengue (N = 11). We found that fold-enhancement of DENV3 infection at a 1:10 serum dilution on a monocytic U937 cell line expressing CD16 (FcγRIII) was the strongest predictor of viremia, while neutralizing antibodies to mature DENV3 and greater neutralization breadth had the strongest protective effects. Neutralization measured using partially immature virus was not directly protective and instead showed non-linear associations with viremia. Sera that competed with a broadly neutralizing antibody for binding to the quaternary envelope-dimer epitope on DENV3 also had lower viremia, while binding responses to other serotypes were not protective. IFN-γ—secreting CD8+ T cells correlated with reduced viremia. Conclusion While enhancing antibodies determine susceptibility to viremia, neutralizing antibodies and antiviral CD8+ T cell responses are protective. Our results may help inform evaluation of future dengue vaccines and therapeutics. Funding Source This research was supported by the Intramural Research Program of the National Institutes of Health (NIH) as well as NIH Bench-to-Bedside Program Funds - Award # 994875, the NIH Director’s Challenge Innovation Award, ReVAMPP grant 1 U19 AI181960-01, and P Topic Categories Immune Mechanisms of Human Disease (HUM)

Opposing Effects of Metoclopramide and Bromocriptine on Melanoma Response to Immune Checkpoint Blockade 2303237

Abstract Introduction Dual immune checkpoint inhibitors (ICIs) targeting CTLA-4 and PD-1 have been effective in treating advanced melanoma, yet the melanoma-specific survival is only ∼52%. The human population is genetically heterogeneous, and we hypothesize that this contributes to the disparate response to ICIs. Our previous studies have demonstrated that host genetics influence ICI outcomes. Genetically heterogeneous mice with subcutaneous syngeneic melanoma tumors differentially responded to dual ICIs. Genetic linkage analysis revealed that the genomic locus containing the prolactin (PRL) gene family highly associates with ICI response. Co-therapy of PRL with ICIs significantly slowed tumor growth compared to ICIs alone. Methods To pharmacologically modulate PRL, we targeted the dopamine D2 receptor (D2R) which inhibits pituitary release of PRL. We utilized FDA-approved D2R agonist bromocriptine (BRC) and antagonist metoclopramide (MCP) to lower and raise systemic PRL, respectively. Melanoma-bearing mice were administered ICIs with or without either agent. In a separate in vitro experiment, MCP was administered to melanoma cells, T cells and macrophages. Results BRC with ICIs accelerated melanoma growth and decreased intratumoral CD8 infiltration over ICIs alone, whereas MCP with ICIs had the opposite effect. Additionally, MCP reprogrammed the tumor-microenvironment toward enhanced interferon signaling, antigen presentation and macrophage activity during immune checkpoint blockade. Moreover, MCP administration increased major histocompatibility complex I and II on melanoma cells, shifted polarization of macrophages to an anti-tumor phenotype, and enhanced T cell activation in vitro. Conclusion Taken together, these results suggest that D2R pharmacologic modulation impacts ICI therapy efficacy and anti-tumor immunity in melanoma. Our findings come with an exciting opportunity to repurpose already FDA-approved drugs as potential co-therapeutics to overcome ICI resistance in advanced melanoma patients. Funding Source 1) National Cancer Institute T32CA009531 2) National Cancer Institute R37CA220482 3) National Institutes of Health P30CA022453 Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)

Tracking memory T follicular helper cells in the draining lymph node following boost vaccination in humans 2257551

Abstract Introduction T follicular helper (Tfh) cells are crucial in germinal center (GC) reactions, supporting B-cell maturation and long-term antibody production. While Tfh dynamics during primary and secondary immune responses are well-studied in mice, little is known about human Tfh behavior in draining lymph nodes after repeat vaccination. Recent advances, such as serial fine-needle aspiration (FNA) of lymph nodes, now make it possible to monitor these responses in humans. The present study aimed to track and characterize human spike-specific Tfh cells in the draining lymph node following SARS-CoV-2 mRNA booster vaccination, and to compare these memory responses to the primary vaccination phase. Methods We conducted serial lymph node FNAs in healthy immunologically naïve adults receiving primary and booster mRNA COVID-19 vaccines (1 year apart). We used single-cell RNA sequencing with paired T cell receptor (TCR) sequencing to analyze spike-specific Tfh clonotypes and transcriptional profiles. Results We show that the post-boost Tfh response was dominated by spike-specific TCR clonotypes already present after the primary vaccination, indicating robust memory recall. A minority of novel spike-specific Tfh clones emerged after boosting, suggesting limited recruitment of new Tfh populations during the secondary germinal center reaction. Secondary germinal center Tfh cells differed markedly from primary Tfh cells: 1) they exhibited a higher frequency of IL-10+ Tfh cells; 2) they had fewer classical germinal center Tfh (with high CXCR5 and PDCD1); and 3) boost-induced Tfh cells showed upregulation of transcription factors such as RUNX3, RUNX1, KLF2, and NFKB1, reflecting a memory-specific transcriptional signature. Conclusion Overall, our data shows that booster vaccination triggers a phenotypically and transcriptionally unique memory Tfh response in human lymph nodes, emphasizing that immune recall involves reactivation of existing memory clones to shape long-term humoral immunity. Funding Source R01AI173203 Topic Categories Immune Mechanisms of Human Disease (HUM)

Impact of innate immune training on lung tissue resident memory formation following RSV infection 2328124

Abstract Introduction Trained immunity is a well-documented phenomenon which can mediate non-specific immunity against pathogens. Secondary challenge following training results in increased production of proinflammatory mediators by innate immune cells. It has been previously shown that this inflammatory microenvironment can influence T cell responses and may alter the Th1/Th2 and Treg/Th17 balance. Here we examined the impact of trained immunity on lung tissue resident memory (Trm) formation and function following respiratory syncytial virus (RSV) infection. Methods Mice were treated intraperitoneally (i.p.) with compounds known to induce trained immunity seven days prior to intranasal infection with RSV. Disease severity was measured via weight loss and airway obstruction throughout initial training and subsequent RSV infection. Lungs and bronchoalveolar lavage (BAL) fluid were harvested 30 days post-RSV infection. Cells from the lung and BAL were stimulated ex vivo with RSV peptides to determine Trm cytokine production. Cells were then characterized using spectral flow cytometric analysis. Results Mice administered β-glucan i.p. prior to RSV infection exhibited a significant decrease in total CD8 Trm number and function in the airways at 30 days post-infection compared to RSV infection alone. RSV disease severity was not impacted by prior β-glucan treatment. Conclusion β-glucan is a well characterized trained immunity stimulus and is a promising adjuvant in vaccine development, with several ongoing clinical trials for both cancer and viral studies. However, our results suggest that β-glucan induced training decreases Trm numbers and function following RSV infection, highlighting the need for further studies in this area. Funding Source N/A Topic Categories Viral Immunology (VIR)

The Role of Pathogen-Restricted Paracrine Protection by T cells in Controlling Viral Infection 2260976

Abstract Introduction It is critical for the immune system to destroy cells harboring intracellular infection to remove pathogen burden. This function is widely attributed to cytotoxic T cells, which can physically engage with their targets through the T cell receptor complex, releasing cytotoxic granules, resulting in a specific death of infected targets. However, effector cytokines tumor necrosis factor-α (TNF) and interferon-γ (IFNγ), secreted by T cells, are themselves cytotoxic in combination to a degree. While TNF has appreciated cell death function through the TNF receptor 1 (TNFR1) signaling pathway, no clear cytotoxic function is attributed to IFNγ. Because of the diffusible nature of these cytokines, it is possible for T cells to elicit cytotoxicity without requiring direct contact with their targets, termed paracrine killing. Whether paracrine killing occurs during viral infection and how it is regulated is unclear. Paracrine killing poses issues of both sensitivity to these cytokines in that high concentrations of these cytokines are needed to affect target cells, as well as specificity in discriminating infected from uninfected host cells. Accounting for both issues, we hypothesize that paracrine killing is elicited through pathogen restriction whereby only infected cells are susceptible to death. Methods Analysis was performed in vitro using the Incucyte live cell imaging system and Western blots with fibroblast targets and a VSV infection model and OT1 T cells were leveraged ex vivo. Results TNF and IFNγ protect cells against the cytopathic effect of the virus. TNF specifically synergizes with VSV resulting in death of the infected cells and the two cytokines have distinct roles that work in concert. We demonstrate that TNF and IFNγ released by activated T cells suppress viral infection of nearby cells in a paracrine manner. Conclusion Here we provide insight and context into how distinct cytokines function in a cooperative manner for immune protection during an infection. Funding Source Mayo Clinic Graduate School of Biomedical Sciences Topic Categories Viral Immunology (VIR)

Neural Network Enabled Real‐Time Plasma Imaging for Inverse Designed Fabrication of Micro/Nano Structures with Ultrafast Laser (Adv. Mater. 47/2026)