Browse Articles

Prevalence and factors associated with anxiety and depression among cancer patients undergoing chemotherapy: a cross-sectional study at a private tertiary hospital in Dhaka, Bangladesh

Purple sulfur bacteria convert aquaculture waste into antioxidant-rich single-cell protein through biofloc technology

Heteronuclear MOF Heterostructures Based on Identical Auxiliary‐Ligand Bridging for Multi‐Function‐Integrated Photonic Devices

ABSTRACT Metal‐organic framework (MOF) heterostructures with multi‐segmented emission and integrated responsiveness hold great potential application in integrated photonic devices, yet reported MOF heterostructures always focus on the assembly of homologous chromophore ligands with similar energy levels, restricting their further function integration. Herein, the first heteronuclear MOF heterostructure is reported based on an identical auxiliary‐ligand bridging strategy towards multi‐function‐integrated photonic devices. Designed ligands with distinct chromophore structures were epitaxially assembled by identical auxiliary‐ligand bridging method to construct the heteronuclear MOF heterostructures. Distinct chromophore structures of ligands endow each MOF block with different energy‐level structures, which generate disparate photon‐responsive behaviors and gain processes in different individual regions. On the basis, the heteronuclear MOF heterostructure can simultaneously integrate different photonic functionalities, including narrow‐band light sources, optical modulation and optical waveguides, which further functions as a prototype of integrated photonic circuit with dynamic logic gate operation. These results offer a novel strategy for the development of MOF heterostructures for multifunctional integrated photonic devices.

All-small-molecule Hydrogels for Safe and Efficient Photoprotection

Directing Defense: ZBP1 Activation during MPXV Infection 2309240

Abstract Introduction Monkeypox virus (MPXV) remains a global health concern due to the recent outbreak that exhibited an increase in human transmission. This highlights the need to better understand the viral host interactions to identify novel antiviral strategies. Z-DNA Binding Protein-1 (ZBP1) is an innate immune sensor that can recognize Z-ribonucleic acid (Z-RNA). Z-RNA is a novel pathogen-associated molecular pattern (PAMP), produced during early viral replication, and can be sensed by ZBP1. Activation of ZBP1 can initiate antiviral signaling pathways that can restrict viral replication and limit disease progression. However, whether ZBP1 contributes to controlling MPXV replication and spread remains a significant gap in knowledge. Methods Wild-type (WT) and ZBP1-knockout (ZBP1-KO) bone-marrow-derived-macrophages (BMDMs) were infected with MPXV to determine the viral replication and spread using single-step and multi-step growth curves. Viral titers were quantified by plaque assay, and viral gene expression was measured by RT-qPCR. In vivo, WT and ZBP1-KO mice were infected intranasally with MPXV, mimicking the respiratory route transmission. Lung tissues were collected at 1, 3, and 5 days post-infection (dpi) to quantify viral titers and viral gene expression. Results Findings reveal that ZBP1 deficiency results in increased MPXV replication and spread during single and multi-step growth curves of MPXV infection, as indicated by an elevated viral titer. Increased viral gene expression was also observed in lung tissues from ZBP1-KO at 3dpi, suggesting an antiviral role for the host ZBP1 during MPXV infection. Conclusion Together, these results demonstrate that ZBP1 plays an antiviral role during MPXV infection. However, further studies are needed to define the host defense pathways involved, such as TBK1 and NF-κB signaling. Understanding how ZBP1 restricts MPXV as Z-RNA is produced during early MPXV infection can help address a significant gap in understanding the viral host interactions. Funding Source GR00012379 Topic Categories Innate Immune Responses and Host Defense: Molecular Mechanisms (INM)

The Autoimmunity-Associated Minor Allele of PTPN22 Accelerates NK Cell Development and Augments Effector Function 2255984

Abstract Introduction Ptpn22 is expressed exclusively in immune cells and shows the highest expression in natural killer (NK) cells, yet its role in NK cells is unknown. Mice expressing the autoimmunity-associated minor allele of Ptpn22, PEP-R619W, have enhanced protection and antiviral immunity during murine coronavirus infection. This protective phenotype is partially driven by augmenting NK cell effector function to restrict viral replication. Due to these findings, we wanted to define the role of Ptpn22 and its PEP-R619W variant in NK cells during development and how they differentially regulate cytokine-mediated activation and cytotoxic function. Methods To investigate the role of Ptpn22 and its variant in NK cell biology, we utilized wild-type (PEP-WT) and CRISPR-Cas9-generated Ptpn22 knockout (PEP-null) and PEP-R619W mice. We assessed the impact of PEP-null and PEP-R619W on NK cell development, maturation, cytokine signaling, and cytotoxic function using flow cytometry. Results In the bone marrow, NK cell numbers were increased, and maturation was accelerated in PEP-null and, more so, in PEP-R619W mice compared to PEP-WT. Mechanistically, Ptpn22 restricts IL-15 signaling, as PEP-null and PEP-R619W NK cells showed enhanced Granzyme B and pro-survival protein expression (Ki67, Bcl-2) following IL-15 stimulation. Furthermore, the addition of IL-15 to IL-12 and IL-18 stimulation elevated IFN-γ production in PEP-R619W NK cells over PEP-WT and PEP-null NK cells. Functionally, PEP-null and PEP-R619W NK cells displayed superior cytotoxicity against tumor targets ex vivo, with the R619W variant again being the most potent. Conclusion Our findings reveal that Ptpn22 is a novel regulator of IL-15 signaling and that its PEP-R619W variant modulates this pathway through additional mechanisms leading to heightened IL-15 responsiveness. This leads to NK cells with augmented effector functions compared to PEP-WT and PEP-null, highlighting the pleiotropic effects of this autoimmune-associated allelic variant. Funding Source NIH Chemical Biology T32 Training Grant GM13206 KU Chemical Biology of Infectious Disease (COBRE) P20GM113117 Topic Categories Innate Immune Responses and Host Defense: Molecular Mechanisms (INM)

Non-invasive profiling of antigen-specific endometrial T cells via Menstrual Effluent 2249626

Abstract Introduction While human T cell responses are well-characterized in peripheral blood, little is known about their role in the female reproductive tract, largely due to the need for invasive sampling. In this work, we leverage menstrual effluent (ME) to establish the first comprehensive profiling of antigen-specific T cell responses in the endometrium. Methods Paired samples of peripheral blood and menstrual effluent (ME) were collected from healthy donors, with ME obtained using menstrual cups (DivaCups). Samples were analyzed using high-parameter spectral flow cytometry following stimulation with peptide megapools from pathogens relevant to women’s health, including cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human papillomavirus (HPV), enabling assessment of T cell responses independent of donor HLA type. Beyond quantifying their frequency, we comprehensively characterized these T cells by assessing activation markers (OX40, CD40L, CD69, CD137, CD25), memory and Treg phenotype (CCR7, CD45RA, Foxp3), tissue-residency markers (CD69, CD103, CD49a, CXCR6), cytokine (IFN‑γ, TNF‑α, IL-4, IL-17a) and cytotoxic molecules production (CD107a, Granzyme A, Granzyme B, Perforin). Results We successfully identified antigen-specific T cells in ME for the pathogens mentioned above, representing, to our knowledge, the first detection of HPV- and EBV-specific T cells in menstrual effluent. Our results revealed high inter-donor heterogeneity and pronounced differences compared with paired peripheral blood. Conclusion These findings establish menstrual effluent as a non-invasive tool for monitoring endometrial immunity and underscore its potential applications in gynecologic health. Funding Source The Tullie and Rickey Families SPARK Awards for Innovations in Immunology at La Jolla Institute. Topic Categories Mucosal and Regional Immunology (MUC)

PD-1 regulates CD8+ T cell tissue resident memory differentiation and function following influenza infection 2260210

Abstract Introduction In addition to its established role in T cell exhaustion, PD-1 is also upregulated in CD8+ tissue-resident memory (TRM) cells. Methods Here, we examine the cell-intrinsic contributions of PD-1 to CD8+ TRM cell generation and function during influenza infection by comparing wild-type (WT) and PD-1 knockout (KO) antigen-specific CD8+ T cells. Results Transcriptional and epigenetic profiling of these populations reveals early and persistent changes in transcriptional regulation and fate decisions. Conclusion Our findings provide new insight into how PD-1 signaling influences the differentiation and function of CD8+ T cells. Funding Source This work was supported by funding from AbbVie. Topic Categories Computational and Systems Immunology (COMP)

Neutrophil-derived vesicles control complement activation to facilitate inflammation resolution 2218223

Abstract Introduction Neutrophils, the most abundant white blood cells and first responders to immune challenges, have long been considered short-lived with unclear evolutionary purpose. We discovered Large Aging Neutrophil-Derived Vesicles (LAND-Vs), generated during neutrophil aging independent of cell death, that modulate immunity by targeting complement activation. This represents the first example of typically pro-inflammatory neutrophils actively dampening inflammation to restore homeostasis. Methods Using novel live imaging, spectral flow cytometry with unbiased clustering, and imaging flow—based machine learning we systematically characterized LAND-Vs, defining their temporal regulation, heterogeneity, pathophysiological roles, and biogenesis. Results Live imaging of neutrophil aging revealed that LAND-Vs are actively produced independent of cell death. These vesicles exert potent anti-inflammatory effects through surface CD55, which inhibits complement C3 convertase, thereby limiting inflammation and tissue damage. In inflamed lungs, LAND-Vs persisted beyond neutrophil decline and complement activity, supported by “do not eat me” signals that prevented macrophage clearance and sustained complement deactivation. Mechanistically, asymmetric CD55 polarization during neutrophil aging drove lipid raft—dependent formation of CD55+ LAND-Vs. Clinically, circulating CD55+ LAND-Vs inversely correlated with COVID-19 severity. Conclusion This work uncovers a previously unrecognized neutrophil function: an active anti-inflammatory role mediated by LAND-V production as a programmed feature of aging rather than cell death. LAND-Vs represent a distinct class of large extracellular vesicles. Their discovery redefines neutrophil aging as an active, biologically purposeful process, extending function beyond cell death. This paradigm shift opens new directions in immunology and translational research with important clinical implications in inflammatory and infectious diseases. Funding Source NIH Topic Categories Immune Response Regulation: Cellular Mechanisms (IRC)

Novel Neuroprotective and Immunoregulatory Mechanisms for the Treatment of Multiple Sclerosis 2259190

Abstract Introduction Multiple sclerosis (MS) is a complex autoimmune disease involving myriad cell types with varied baseline immunological profiles across patients. Treatment of MS remains a challenge with substantial annual relapse rates and disability progression. Absent combination therapies, new mechanisms bridging innate and adaptive immunity to provide protection from neurodegeneration need further exploration. Methods Efficacy of a novel treatment was tested in passive experimental autoimmune encephalomyelitis (EAE) and a demyelinating cuprizone model. For EAE, a MOG35-55 emulsion was injected to donors. After 10 days, harvested splenocytes were incubated with IL-12, MOG35-55, and anti-IFNy for three days after which they were injected into recipients. For the cuprizone model, mice were fed powdered cuprizone diets for 5 weeks. Spinal cords and brains were collected for histology, gene expression and flow cytometry. Differentiation, cytokine production and cell survival were studied in cultures of CD4+ T cells, microglia and neurons. Results In cultures of primary CD4+ T cells, treatment provided a greater than 50% reduction in IFNy+ and IL17+ cells at 100 nM. Similarly, microglia treated ex vivo produce less IL-6, IL-1β and TNF. Meanwhile, a 4-fold increase in neuronal cell viability in oxidative stress conditions after treatment. In EAE, treatment reduced IFNy+ and IL17+ CD4+ cells by 2-fold, along with reduction of GFAP+ cells histologically and decreased expression of Il1b and Tnf in the spinal cord. In the cuprizone model, treatment provided a near complete protection against oligodendrocyte precursor cell (Olig2+ Pdgfr+) loss while preventing the generation of TNF+ microglia (CD11b+ Iba1+). Histologically, this resulted in a 70% reduction in demyelination. Conclusion NIMML has developed a novel oral, once-daily treatment for MS and other neuroinflammatory diseases that provides therapeutic efficacy by directly impacting CD4+ T cells, microglia and neurons implicated in these diseases. Funding Source n/a Topic Categories Therapeutic Approaches to Autoimmunity (THER)

IL-1b-driven bystander proliferation of memory CD4 T cells partially depends on IL-2 2306098

Abstract Introduction Levels of the inflammatory cytokine IL-1b are elevated during aging and are associated with a number of morbidities including autoinflammatory diseases, cardiovascular disease, neurodegenerative diseases, pulmonary disease, type 2 diabetes, and rheumatoid arthritis. Our previous studies of human peripheral blood mononuclear cells (PBMCs) demonstrated that innate cytokines (IL-1b and IL-6) could down-regulate expression of CD127 on T cells and induce proliferation of memory CD4 T cells in vitro, without upregulating the survival factor Bcl2. Here, we revisited these studies to better understand the mechanism(s) of how chronic innate cytokines, like IL-1b, interfere with CD4+ T cell homeostasis. Methods PBMCs or purified T cells from healthy human participants were incubated with recombinant human IL-1b, IL-2, or IL-7, as well as blocking reagents targeting these signaling pathways. After 7-9 days, cellular subsets and proliferation were assessed by flow cytometry. Results Confirming our previous studies, we found that proliferation of CD4+ T cells in response to IL-1b stimulation of PBMCs differs from that induced by the homeostatic cytokine IL-7 in that IL-1b induces a small polyclonal population of primarily CD4+ memory T cells to rapidly proliferate. While IL-7 stimulation could induce proliferation of purified T cells, IL-1b stimulation could not, demonstrating that an additional PBMC-derived soluble factor is required. Inhibition of IL-2 in PBMC cultures decreased IL-1b stimulation-induced proliferation, suggesting that IL-2 generated during the culture partially contributes to the IL-1b-induced bystander proliferation of memory CD4+ T cells. Conclusion Our results provide a novel mechanism of how persistent innate cytokines such as IL-1b can disrupt T cell homeostasis during aging and chronic infections. Funding Source n/a Topic Categories Lymphocyte Differentiation and Peripheral Maintenance (LYM)

Switching Type‐II to S‐scheme Charge Transfer Through Fermi Level Modulation

ABSTRACT Directly switching the type of electron transfer from Type‐II to S‐scheme at the heterojunction interfaces of a two‐component photocatalyst is crucial for improving charge separation efficiency in semiconductor‐based photocatalysis technology. A major challenge lies in the effective control of the interfacial band‐edge position or electronic properties of a two‐component photocatalyst. Here, we constructed a “directional valve” in a Zn x Cd 2‐x S 2 –crystalline carbon nitride (Zn x Cd 2‐x S 2 –CN) heterojunction through Fermi level modulation to selectively switch Type‐II to S‐scheme charge transfer. Experimental validation using advanced scanning probe microscopy and in situ photoemission directly observed the switched electron transfer dynamics. The metal probe‐assisted in situ X‐ray photoelectron spectroscopy (XPS) directly demonstrates the electron transition from Type‐II to S‐scheme pathways at the interface, corroborated by illumination‐induced surface potential shifts. Furthermore, the S‐scheme charge transfer in Zn x Cd 2‐x S 2 –CN heterojunction contributed to a four times higher CO 2 photoreduction activity than the Type‐II one. This study provides a new paradigm for rationally controlling interfacial charge dynamics through band engineering.

Atomic-precision π-driven peptide hydrogel nanofibers with ordered water channels

Periodontal Pathogen—Derived Phosphoglycerol Dihydroceramides Attenuate Piezo1-Mediated Mechanosensing in Macrophages 2309477

Abstract Introduction Phosphoglycerol dihydroceramides (PGDHCs) produced by Porphyromonas gingivalis (Pg) are emerging virulence factors that contribute to periodontal inflammation and alveolar bone destruction. Macrophage mechanosensing mediated by Piezo1 plays a crucial role in regulating inflammatory signaling and osteoclastogenesis. However, whether bacterial lipid metabolites interfere with Piezo1-dependent mechanotransduction in macrophages remains unknown. This study examined the impact of Pg—derived PGDHC on macrophage mechanosensing and its contribution to periodontal bone loss. Methods Bone marrow—derived macrophages (BMDMs) were stimulated with wild-type Pg (Pg WT), a serine palmitoyltransferase—deficient strain lacking PGDHC (Pg SPT-null), or purified PGDHC. Piezo1 activity was assessed by Yoda1-induced Ca²+ influx. Osteoclastogenesis from BMDMs was evaluated following Piezo1 activation in the presence or absence of PGDHC. The role of non-muscle myosin IIA (MYH9) was examined using immunofluorescence, blebbistatin, and siRNA-mediated Myh9 silencing. Experimental periodontitis was induced by ligature placement with oral inoculation of Pg WT or Pg SPT-null for 14 days, and alveolar bone loss was quantified by micro-CT. Results Pg WT and purified PGDHC significantly suppressed Piezo1-mediated Ca²+ influx in macrophages, whereas Pg SPT-null and other oral bacteria had no effect. PGDHC counteracted Piezo1 activation—mediated suppression of osteoclast differentiation. PGDHC colocalized with MYH9, and both blebbistatin treatment and Myh9 silencing disrupted Piezo1-mediated Ca²+ influx. In vivo, Pg WT inoculation induced significantly greater periodontal bone loss than Pg SPT-null. Conclusion Pg-derived PGDHC impairs Piezo1-mediated mechanosensing in macrophages through MYH9-dependent cytoskeletal regulation, thereby promoting osteoclastogenesis and periodontal bone loss, and identifying PGDHC inhibition as a potential therapeutic strategy for periodontitis. Funding Source NIH grants: DE-025255, DE-027851, DE-028715, DE-029709, DE-032156, DE-032907, DE-034069, DE-034154. Topic Categories Microbial, Parasitic, and Fungal Immunology (MPF)

Role of Neurotransmitter Transporters in Neuroimmune Communication and Cellular Responses 2256336

Abstract Introduction Measuring the dynamics of neurochemical-regulated immunity has been an area of research due to its implications in understanding gastrointestinal inflammation, neurodegeneration, and depression. Nervous system innervates immune organs, facilitating dynamic communication between neurons and immune cells. Sympathetic neurons release norepinephrine, a key neurotransmitter (NTTs) that modulates immune activity. Membrane proteins (transporters) are essential in maintaining neurochemical homeostasis by mediating the reuptake of synaptic neurochemical. Dysregulation of these transport mechanisms can alter neurotransmitter availability, thereby influencing immune responses. Methods Fast-Scan Cyclic Voltammetry to measure subsecond NTTs release dynamics following lipopolysaccharide stimulation. Cytokine production and membrane transporter expression were quantified using ELISA and flow cytometry, respectively. Pharmacological inhibition of transporters was achieved using different drugs to determine their roles in modulating immune responses. Results Pharmacological inhibition of specific transporters altered NTTs levels and cytokine production. Dopamine and Norepinephrine transporter inhibition significantly increased NTTs concentrations and pro-inflammatory cytokine expression, whereas serotonin and organic cation transporter inhibition produced more modest or variable effects. These findings suggest that transporter activity directly influences immune signaling pathways through modulation of NTTs availability at synaptic interface. Conclusion This study demonstrates that NTTs transporters are critical regulators of neuroimmune communication. Their inhibition alters both neurochemical signaling and immune function, highlighting the importance of transport-mediated control in maintaining neuroimmune homeostasis. There is no simple statement like “Norepinephrine is pro- and anti-inflammatory”. It is better to say norepinephrine modulates immune function in a context dependent manner. Funding Source National institute of Health and National Science Foundation Topic Categories Neuroimmunology (NEUR)

RGS16 as a Therapeutic Target to Overcome TGFβ-Induced Resistance in Adoptive T Cell Therapies 2250696

Abstract Introduction T cells, particularly CD8+ T cells, play a central role in immune defense against intracellular pathogens and in tumor immunosurveillance. However, within tumors, these cells often become functionally exhausted, limiting the effectiveness of T cell—based immunotherapies. To maintain self-tolerance and immune homeostasis, T cell activity is tightly controlled by immunosuppressive mechanisms, including immune checkpoint molecules and anti-inflammatory cytokines. Among these, transforming growth factor-β (TGFβ) is a key pleiotropic cytokine known to suppress T cell responses. Methods To identify novel immunosuppressive genes downstream of TGFβ signaling, we performed mRNA sequencing of human CD8+ T cells activated with or without the addition of TGFβ. Differential gene expression analysis was conducted to identify TGFβ-regulated candidates. Functional validation was carried out using CRISPR-Cas9—mediated knockout in both Jurkat T cells and primary human CD8+ T cells to assess the role of identified genes in T cell function. In vivo studies involved adoptive transfer of gene-edited T cells into tumor-bearing mice to evaluate antitumor efficacy. Results Transcriptomic analysis revealed several genes upregulated by TGFβ, among which RGS16, a member of the regulator of G protein signaling (RGS) family, emerged as a strong candidate for a negative regulator of T cell function. Functional studies showed that RGS16 knockout markedly enhanced cytokine production, proliferation, and cytotoxic activity in both Jurkat cells and primary human CD8+ T cells. Moreover, adoptive transfer of RGS16-deficient T cells into tumor-bearing hosts led to improved tumor control and prolonged survival compared with controls. Conclusion Our findings identify RGS16 as a key downstream effector of TGFβ-mediated immunosuppression and a promising molecular target to potentiate T cell—based immunotherapies by restoring effector function under immunosuppressive conditions. Funding Source Augusta University (Start up funds) Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)

In Vitro Characterization of Glioblastoma Inflammatory Signatures: Insights into Resistance and Model Selection 2260327

Abstract Introduction Glioblastoma multiforme (GBM) is a highly aggressive neurological cancer marked by treatment resistance and recurrence. Inflammatory profiling is essential to reveal mechanisms of immune evasion and molecular remodeling in GBM that drive the need for cancer subtype-specific treatments. This study examines inflammation-associated gene expression and stress responses in two immortalized GBM cell lines in a model of treatment-induced inflammation, with correlations to glioblastoma tumor subtypes, to advance patient treatment decision-making. Methods LN-18 and LN-229 human GBM cells were cultured and stimulated with lipopolysaccharide (LPS). Total RNA was extracted and expression of key immune genes (CCL2, STAT3, IL-33, CD274, TGF-β, IL-10) and angiogenic neuropilin-1 (NRP1) was assessed by RT-qPCR. Results At baseline, LN-18 cells expressed 40% more CD274 than LN-229 cells, while NRP1 was nearly five times greater in LN-229. LPS exposure reduced NRP1 in LN-229 by > 70%, eliminating previous differences with LN-18. The same treatment increased CCL2 sevenfold in LN-229 versus an untreated control and ∼11-fold compared to treated LN-18 cells, indicating a strong immune response in LN-229 cells. STAT3 was significantly upregulated in LN-18 cells after LPS exposure compared to LN-229, suggesting differential inflammatory signaling between subtypes. TGF-β, IL-10, and IL-33 levels were low across all cell lines and conditions. Conclusion LN-229 cells present a distinct inflammatory and mesenchymal-like gene signature relative to LN-18. These unique profiles emphasize the importance of model selection in advancing our understanding of GBM. Our findings support LN-229 as a valuable model of aggressive glioblastoma and implicate NRP1 as a critical target for understanding mechanisms of resistance. Expanded inflammatory profiling will advance clinical translation opportunities, guide targeted immunotherapies, and ultimately improve outcomes for patients living with glioblastoma. Funding Source Transformative Seed Grant from the Prisma Health Education and Research Institute and philanthropic funds from the Prisma Health Institute for Translational Oncology Research. Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)

Gene expression profiling of immune cells in blood from patients with coronary Artery Disease 2235454

Abstract Introduction Coronary artery disease (CAD) is a leading cause of death worldwide and is increasingly recognized as an immune-mediated disorder. Defining immune alterations in CAD can provide mechanistic insights and therapeutic targets. Methods Single-cell multi-omics (RNA- and CITE-seq) was applied to profile peripheral blood mononuclear cells from 39 CAD patients undergoing coronary angiography. After quality control and integration (∼416,000 singlet cells), we analyzed major immune lineages, transcriptional and proteomic states, and T-cell receptor repertoires. Results Distinct states of T cells, B cells, NK cells, and monocytes were identified. Weighted nearest neighbor analysis revealed subsets with altered activation and checkpoint signatures, including heterogeneous CD4+ T-cell populations. TCR sequencing demonstrated oligoclonal expansion of 335 clones by TCRB CDR3 sequences. GLIPH2 clustering revealed enrichment of MHC-II—restricted motifs with reactivity to ApoB epitopes, highlighting antigen-driven T-cell responses as potential contributors to CAD progression and potential targets for precision immunotherapy Conclusion Integrating this new dataset with published datasets provides an integrated atlas of immune dysregulation in CAD. Funding Source n/a Topic Categories Immune Mechanisms of Human Disease (HUM)

Mucosal vaccination with TLR9 agonists promote the development of tissue resident helper cells and mucosal humoral immunity against influenza 2259178

Abstract Introduction Current influenza (flu) vaccination strategies rely on accurate prediction of the circulating strains for the upcoming season. Therefore, the induction of a cross-reactive memory response is desirable. Tissue resident helper (Trh) cells are a population T follicular helper (Tfh)-like CD4+ tissue resident memory T cells induced by flu infection that promote the development of tissue resident memory B (Brm) cells. Vaccination strategies that induce Trh cell differentiation may prove useful in the development of cross-reactive immunity to flu infections, however no such adjuvant formulation is known to accomplish this. Methods Using an intranasal immunization strategy with the conserved influenza A nucleoprotein (NP), we screened multiple adjuvants for their ability to induce Trh cell, Brm cell and airway antigen specific IgG2c and IgA development. Utilizing a conditional knockout model, we investigated the role of T cell -intrinsic TCF-1, a transcription factor required for Tfh cell differentiation, in the development Trh cell and mucosal B cell responses following intranasal vaccination. Utilizing human tonsil organoids to model the , we investigated the the ability of of CpG ODN to promote the human adaptive immune response. Results The TLR9 agonist CpG ODN induced Trh cell development which was associated with the induction of lung resident GC B cells, CXCR3+ Brm cells and NP-specific IgG2c and IgA in the airways, which was dependent on T cell-intrinsic TCF-1. Mice intranasally immunized with CpG ODN and NP, or other conserved and variable antigens, were protected against lethal challenge from both H1N1 and H3N2 flu strains. In human tonsil organoids, CpG ODN could promote the differentiation of plasmablasts. Conclusion Together, our data indicates mucosal immunization with CpG ODN promotes the development of Trh cells, mucosal B cell responses, and protection against multiple strains of influenza A. This work has implications for the development of universal flu vaccines Funding Source R01 AI151139 Topic Categories Vaccines and Immunotherapy (VAC)

BHLHE40 Orchestrates ILC3 and RORγt+ APC-Mediated Barrier Immunity 2309149

Abstract Introduction A central feature of the intestinal immune system is its ability to protect against pathogens while maintaining tolerance to commensal microbiota. Group 3 innate lymphoid cells (ILC3s), which express the transcription factor RORγt, produce effector cytokines such as IL-22 that are essential for epithelial repair and barrier restoration. Recent studies have identified a subset of RORγt+ antigen-presenting cells (APCs) that promote peripherally induced regulatory T cell (pTreg) responses in the intestine. However, the molecular mechanisms by which RORγt+ immune cells coordinate tissue protection and antigen-specific tolerance are not well defined. Here, we investigated the role of the transcription factor Bhlhe40 in regulating intestinal mucosal immunity. Methods Bulk and single-cell RNA sequencing were used to define Bhlhe40-dependent transcriptional programs in ILC3s and RORγt+ APCs. Innate colitis and Helicobacter hepaticus-specific T cell transfer models were used for assessing the function of Bhlhe40 in vivo. Results We identified Bhlhe40 as a central regulator of both ILC3- and RORγt+ APC-dependent mucosal immunity. TNF-like ligand 1A (TL1A) stimulation and colitis enhance intestinal ILC3s expression of Bhlhe40 in mice and humans. Basal Bhlhe40 expression in ILC3s is essential for efficient transcription of cytokine effectors and maintenance of mucosal immunity, whereas TL1A-induced upregulation of Bhlhe40 further amplifies these effects by epigenetic imprinting. Mechanistically, Bhlhe40 regulated expression of the co-stimulatory molecule Tnfsf4 (OX40L) on ILC3s, supporting the induction and maintenance of Helicobacter hepaticus-specific Tregs. Bhlhe40 is also highly expressed in RORγt+ APCs and required for the expression of maturation markers as well as optimal generation of antigen-specific Tregs and oral tolerance. Conclusion Our study reveals a central role for Bhlhe40 in shaping both intestinal ILC3 effector response as well as antigen-specific tolerance in shaping barrier immunity. Funding Source N/A Topic Categories Mucosal and Regional Immunology (MUC)