Allergy

Asthma is a chronic inflammatory disease affecting over 300 million people worldwide. This disease has multiple underlying etiologies, and a major endotype of asthma is characterized by cellular and molecular signatures of type 2 (allergic) inflammation. In this study we conducted bronchoscopies with airway segmental allergen challenge in allergic asthmatics to dissect airway responses to allergen. Using mass cytometry and single-cell RNA sequencing, we characterized with high resolution the airway immune landscape before and after allergen challenge and the heterogeneity present between subjects. This heterogeneity generally falls along a type 1/ type 2 axis. In type 2 high individuals, we identified allergen-reactive Th2 cells by using TCR sequences to barcode clonal T cell populations in single-cell genomic and activation-induced marker expression assays. These potentially pathogenic Th2 cell clones were present systemically and expanded following allergen challenge, connecting local lung inflammation to systemic clonal Th2 cell dynamics. Th2 cell airway ingress was coordinated with myeloid cell expression of T cell chemoattractants including CCL17 and CCL22. This study provides insight into the molecular and cellular components of allergen-induced tissue inflammation in asthma. Deeper resolution of the T cell response to aeroallergens may inform novel diagnostic and therapeutic strategies for asthma and other allergic airway diseases.

Background Childhood asthma has been linked to individual foods, nutrients, diet-quality scores, and broad dietary patterns, but specific early-childhood food co-consumption patterns and their microbial/metabolic correlates remain unclear. Objective To identify data-driven early-childhood dietary patterns associated with asthma/wheeze, evaluate prospective associations with age-6 asthma/wheeze, assess external support in NHANES, and characterize associated gut microbiome and stool/plasma metabolomic profiles. Methods We analyzed age-3 food frequency questionnaire data from children in the Vitamin D Antenatal Asthma Reduction Trial. Dietary patterns were derived from log-transformed, energy-residualized, standardized food-frequency variables using principal component analysis. Associations with age-3 asthma/wheeze were tested using covariate-adjusted logistic regression. Prospective associations were evaluated using age-6 asthma/wheeze as the outcome. Leading PC food-cluster proxies were evaluated in NHANES 2021-2023 among children aged 2-3 years, with sensitivity analyses in ages 2-5 and 2-8 years. Selected PCs were tested for associations with gut microbiome, stool metabolome, and plasma metabolome features. Results PC1 contrasted a sweet snack/fried-food pattern with a fruit/vegetable-rich pattern, whereas PC3 captured a processed meat/fried-food axis. PC3 showed the strongest positive association with age-3 asthma/wheeze (odds ratio per 1-SD increase, 1.42; P = 0.00109). Age-3 dietary PCs were prospectively associated with age-6 asthma/wheeze, with the overall PC set improving model fit in permutation testing (likelihood-ratio statistic = 20.3; empirical P = 0.033) among 394 cases and 397 controls. In NHANES children aged 2-3 years, the PC3 food-cluster proxy was positively associated with current asthma (odds ratio, 1.59; 95% confidence interval, 0.95-2.67). PC3 was also linked to gut microbial and stool/plasma metabolomic variation, including steroid sulfate, vitamin E-related, nucleoside-related, and lipid-related metabolites. Conclusions Early-childhood asthma/wheeze-associated dietary signals were better represented as food co-consumption patterns than isolated single-food effects. Age-3 dietary patterns were associated with concurrent and prospective asthma/wheeze, showed directionally consistent NHANES support, and were linked to microbiome and metabolomic variation.

Background In adults, cold-attributable mortality exceeds heat-attributable mortality roughly 17-fold. Child-specific evidence has begun to emerge only recently - a nationwide Brazilian case-crossover study located the minimum mortality temperature (MMT) for under-five deaths, and a 56-country survey-based analysis linked monthly temperature anomalies to under-five mortality - but no multi-country, climate-zone-resolved estimate of the childhood respiratory-infection MMT exists, and whether temperature variability is independently associated with childhood respiratory mortality at the global scale is unknown. We quantified both. Methods We combined Global Burden of Disease 2023 mortality estimates, lower respiratory infection (LRI) deaths at ages 0-19 years and asthma deaths at ages 0-24 years, 171 countries, 1990-2023 - with 0.5 deg monthly land temperature and diurnal temperature range (DTR) fields from C-LSAT/C-LDTR (1901-2023). Four exposure dimensions (annual mean, DTR, seasonal amplitude, interannual variability) entered two-way fixed-effects models with Driscoll-Kraay standard errors. A quadratic term in mean temperature located the MMT, with percentile confidence intervals from a 300-replication country-cluster bootstrap. Future-exposure leads, country-level detrending, and permutation tests assessed contemporaneous causality, applied to both the linear coefficients and the quadratic term generating the MMT; national pneumococcal conjugate vaccine (PCV3) coverage and ambient PM2.5 exposure series were added as time-varying mechanistic covariates. Results The childhood LRI MMT was 17.1 C (95% CI 14.7-19.8), the 36th percentile of the annual-temperature distribution; zone estimates were 24.7 C in tropical and 15.8 C in subtropical countries, with weak temperate and no subarctic identification. The quadratic term underpinning the MMT, however, failed both falsification checks - future temperatures reproduced the U-shape and country-level detrending erased it - so these MMT values describe a trend-level geographic pattern of the annual construct rather than a contemporaneous dose-response. Interannual temperature variability was positively associated with LRI (+0.278, 95% CI 0.102-0.454; p = 0.002) and asthma mortality (+0.836, 95% CI 0.447-1.226; p = 2.6 x 10^-5) per 1 C, but future-exposure models returned nearly identical significant coefficients and detrending erased significance, supporting only a trend-level association; adjustment for national PCV3 coverage and PM2.5 exposure left these estimates essentially unchanged. Annual mean temperature was likewise inversely associated with both outcomes at the trend level; DTR and seasonal amplitude showed no independent within-country effects. Conclusions This study provides the first multi-country, climate-zone-resolved geography of the optimal temperature for childhood respiratory survival, spanning 171 countries; because the underlying quadratic association is trend-level, the estimates are directional. The observed variability-mortality associations are trend-level signals rather than contemporaneous causal evidence; daily-scale, child-specific designs are required to determine whether short-term thermal variability affects paediatric respiratory mortality.

Background: Patients receiving anti-TNF treatment for chronic inflammatory disease display impaired antibody responses, but it remains unclear how immune memory formation is affected. We evaluated antibody responses and memory B cells (Bmem) after COVID-19 booster vaccination in inflammatory bowel disease (IBD) patients receiving anti-TNF treatment. Methodology: Blood was sampled at baseline, 1, and 6 months after WH1/BA.5 bivalent or XBB.1.5 monovalent vaccination from 27 IBD patients receiving intravenous anti-TNF and 44 controls. Neutralizing antibodies were measured using an infectious virus assay. SARS-CoV-2 spike receptor binding domain (RBD)-specific serum IgG was quantified by ELISA, and RBD-specific Bmem were immunophenotyped by flow cytometry using recombinant proteins from ancestral, Omicron BA.1, BA.5, XBB.1.5, and JN.1 variants. Results: Serum IgG to vaccine RBD and neutralizing antibodies in patients increased pre to 1 month post-vaccination, but were lower than controls. Ancestral-, BA.5- and XBB.1.5-specific Bmem increased after vaccination but were significantly lower in patients than controls. Within RBD-specific Bmem, frequencies of recently activated CD21lo cells were increased after vaccination, and were higher in patients than controls. Fewer antigen-specific Bmem in patients expressed IgG4, and more expressed IgG3 or IgD following vaccination. Following vaccination, more RBD-specific Bmem recognized multiple viral variants. However, patients had fewer Bmem that could bind to subvariants than controls. Conclusion: Antibody and Bmem responses to COVID-19 booster vaccination in anti-TNF-treated IBD patients displayed reduced capacity, durability and cross-reactivity, suggesting impaired immune memory for protection against breakthrough infection. This supports the recommendation for annual booster vaccination to prevent severe disease and viral spread.

Interactions between intraepithelial lymphocytes (IELs) and the intestinal epithelium are central to mucosal homeostasis and disease. However, mechanistic in vitro studies describing their crosstalk in humans are limited by scarceness of primary material and insufficient knowledge about co-culture requirements. Here, we establish an autologous human duodenal IEL-organoid co-culture system encompassing expandable and bankable IEL and organoid protocols, with co-culture conditions that allow viability of both cell types. This system enables successive interrogation of lympho-epithelial interactions starting from minimal biopsy material. Under baseline conditions, CD45CD8CD103TCR{beta} IELs retain tissue-residency and effector features and induce an epithelial interferon response and chemokine production, without overt epithelial apoptosis. IL-15 and IL-21, essential cytokines involved in IEL-activation in intestinal enteropathies like celiac disease, increases granzyme B expression and interferon-{gamma} secretion but do not trigger epithelial cell death. However, enforcing IEL-epithelial contact using an anti-CD3-anti-Ep-CAM bispecific antibody induces epithelial apoptosis accompanied by increased tumor necrosis factor (TNF) and FAS-ligand (FASLG) secretion. These findings validate the platforms ability to resolve non-destructive and cytotoxic lympho-epithelial interaction and provide a tractable system for studying intestinal inflammation and immune-mediated epithelial cell death.

Undernutrition is an intergenerational global health challenge. Environmental enteric dysfunction (EED) is a small intestinal (SI) disorder characterized by villous atrophy, gut barrier dysfunction, malabsorption and systemic inflammation. To examine its pathogenesis and role in undernutrition, we performed esophagogastroduodenoscopy on undernourished Bangladeshi women with EED and their healthy counterparts. Histologic characterization of duodenal mucosal biopsies, aptamer-based proteomic analyses of their duodenal mucosa and plasma, plus metagenomic analyses of their duodenal and fecal microbiota, revealed associations between bacterial taxa and duodenal tissue and plasma proteomes indicative of EED. Colonization of germ-free female mice with consortia of cultured duodenal bacteria from these women, followed by measurements of SI bacterial abundances, SI cellular patterns of gene expression (single nucleus RNA-seq), plus proteomic and flow cytometric analyses disclosed bacterial, epithelial, and immune features of EED in dams and their offspring resembling those in the women. These findings have diagnostic and therapeutic implications.

Immune adaptation after birth requires coordinated remodeling across the airway-blood axis, yet how these compartments communicate during early postnatal life remains poorly understood. In preterms, dysregulation of this immune response determines mortality and morbidity. We performed paired single-cell RNA sequencing (scRNA-seq) and mass spectrometry-based proteomic profiling of airway samples (deep pharyngeal aspirates, DPA) and matched whole blood from 19 neonates spanning extreme preterm (<28 weeks) to term gestation, sampled at two postnatal timepoints (1-3 days and 4-10 days). This integrated multiomic atlas revealed coordinated and compartment-specific immune adaptation across the airway-blood axis during the first week of life. We observed gestational age-dependent shifts in cell composition in both compartments, including expansion of immature hematopoietic and myeloid populations in blood and distinct myeloid and epithelial programs in DPA, accompanied by compartment-specific inflammatory and innate immune gene expression that evolved during the first week of life. Unexpectedly, we identified a circulating respiratory epithelial-like cell population in neonatal blood whose abundance correlated with prematurity and lung disease and which we validated by flow cytometry as well as in independent datasets. Matched plasma proteomics revealed a gestational age axis and a disease-associated axis; an Organ-to-System Score derived from lung-restricted plasma proteins tracked lung injury severity and distinguished trajectories toward chronic lung disease as early as 72 hours after birth. Together, these multiomic data describe coordinated and divergent immune programs across mucosal and systemic compartments in early preterm life, identify circulating respiratory epithelial-like cells as a candidate blood-accessible signal of airway-blood interface perturbation, and prioritize ciliated-myeloid signaling (LAMA5-ITGB1) as a candidate axis underlying neonatal lung disease. This systems-level framework provides a platform for biomarker discovery and mechanistic studies in larger cohorts.

Background: The systemic immune responses associated with persistent respiratory symptoms (PRS) after exposure to airborne environmental pollutants remain poorly understood. Objective: To identify immune disturbances associated with PRS, defined as persistent wheeze, cough, or breathlessness, we examined systemic immune responses and airway function in a cross-sectional cohort with detailed histories of airborne pollutant exposure. Methods: Never-smoking post-deployment Veterans with PRS (n=16) or without PRS (n=24) underwent chest computed tomography, pulmonary function testing, and oscillometry to assess structural and functional airway abnormalities. Peripheral blood mononuclear cells (PBMCs) were stimulated with anti-CD3/CD28 antibodies, lipopolysaccharide, or {beta}-glucan, and cytokine production was measured. Correlation analyses evaluated associations between cytokine responses and physiological measures of airway function. Results: Oscillometry, but not conventional pulmonary function testing or chest computed tomography, detected small-airway abnormalities in participants with PRS, including significantly greater frequency dependence of resistance and higher resonant frequency. Baseline PBMC cytokine concentrations were similar between groups. After stimulation, however, PBMCs from participants with PRS showed increased IL-17A production consistent with a type 17 (T17) response; innate stimulation also increased the type 2 (T2) cytokines IL-33 and IL-4. T2/T17 cytokine responses correlated positively with oscillometric measures of small-airway dysfunction. Conclusion: Individuals with PRS exhibited a stimulus-dependent systemic T2/T17 immune signature that was associated with early small-airway dysfunction. Clinical Implication: Stimulus-dependent systemic immune profiling, combined with oscillometry, may help identify early respiratory abnormalities in pollutant-exposed individuals whose conventional pulmonary tests remain normal.

Protein and glycan antigens synthesized by gut microbes stimulate circulating and secreted antibody production. Despite continuous exposure of hosts to the plant glycans that constitute dietary fiber, it remains unclear whether these foreign structures induce mucosal immune responses. We report that humans and mice generate antibodies specific for common glycans in plant foods. Oral exposure to individual fiber types induced T cell-independent, glycan-specific IgM and IgA. The induction of anti-fiber antibodies required colonization by particular microbes, since germ-free mice and mice harboring representatives of several bacterial phyla failed to respond. The OMM12 model community was sufficient to rescue antibody induction, and dietary fiber glycans were detected on the surfaces of OMM12 microbes, suggesting a route by which bacteria trigger anti-fiber immune responses. Our results reveal a direct impact of dietary fiber on the adaptive immune system with implications for host control of fiber breakdown by bacteria in the gut lumen.

Seeking a simple vaccine to protect against all cancer-associated human papillomaviruses (HPV), L2 residues 17-36 of both HPV16 and HPV31 displayed on the surface of an Adeno-Associated Virus-Like Particle (AAVLP-HPV) was developed. Here, a phase 1 randomized, placebo-controlled, double-blind clinical study has been conducted in 20 male and female subjects at a single dose level (20 ug) without an adjuvant. AAVLP-HPV vaccine administration was safe and well tolerated. Repeat vaccination with AAVLP-HPV elicited L2-specific neutralizing antibodies of modest titer in serum. Antibodies cross-reactive with L2 of diverse HPV types were detected, but responses were weak in most vaccinees. We conclude that while AAVLP-HPV vaccination is well tolerated, an adjuvant is likely needed to consistently elicit durable and broadly neutralizing responses.

BackgroundAsthma exacerbations are caused by dysregulated cellular interactions between airway and immune cell populations. Circulating microRNAs (miRNAs) are potential biomarkers for asthma exacerbations; however, their target airway cells remain poorly defined. ObjectiveTo identify the cell types that are regulated by the circulating microRNAs linked to asthma exacerbations and the extent to which the cells are regulated by miRNAs. MethodsWe integrated a curated panel of exacerbation-associated circulating miRNAs with single-cell RNA sequencing (scRNA-seq) profiles from induced sputum of 16 asthma patients and 8 healthy controls. Experimentally validated miRNA-target interactions were combined with cell-type-specific differential expression. Elastic Net regression and SHAP analysis quantified gene-level regulatory contributions, yielding a composite Regulation Strength metric. Findings were validated against four independent GEO datasets. ResultsImmune cells, including monocytes, dendritic cells, and macrophages, demonstrated the strongest statistically significant miRNA regulatory signals, in contrast to airway epithelial cells.hsa-miR-222-3p showed opposing regulatory effects in mature versus alveolar macrophages, indicating differentiation-state-dependent activity, while B_Plasma cells showed no detectable regulatory effect from any miRNA tested. Independent GEO validation confirmed higher expression of protective miRNAs (hsa-miR-126-3p, hsa-miR-146b-5p) in healthy individuals, consistent with prior CAMP cohort associations. ConclusionCirculating miRNAs show cell-type-specific regulatory activity, strongest in monocytes, dendritic cells, and macrophages. hsa-miR-222-3p showed opposing regulatory directions between macrophage subtypes, while B_Plasma cells showed no effect, validated across independent GEO cohorts.

Background Exposure to environmental tobacco smoke (ETS) negatively affects children`s health, but few studies examined parental smoking behaviour in families of children with respiratory diseases. We studied parental smoking prevalence, characteristics, and changes over one year among families in the Swiss Paediatric Airway Cohort (SPAC). Methods We included children aged 0-17 years referred to paediatric respiratory outpatient clinics in Switzerland from 2017 to 2024. Parents answered a questionnaire at the initial clinic visit and again after one year. We used multivariable logistic regression to explore the characteristics of mothers and fathers who smoked and assessed changes in smoking behavior over one year. Results Among 4,199 children (median age 9 years [IQR 5-12]), 31% were exposed to parental smoking at baseline (paternal smoking: 16%; maternal smoking: 6%; both parents smoking: 9%). Mothers were more likely to smoke if they had a lower education level (OR 2.0, 95%CI 1.6-2.5 for compulsory education vs university education), did not have Swiss nationality (OR 1.3, 1.0-1.6) and lived in a socially disadvantaged neighborhood (OR 1.3, 1.0-1.7). Similar associations were observed for fathers. In addition, fathers were more likely to smoke if they were unemployed (OR 2.0, 1.3-3.2 vs having a full-time job. The strongest predictor of smoking was having a partner who smoked, with ORs above 6 for both mothers and fathers. Parents of 2,338 children completed the one-year follow-up questionnaire. Data from 2226 mothers and 1895 fathers showed that among baseline smokers with follow-up data, 225 (78%) mothers and 382 (81%) of fathers continued smoking, and only 63 (22%) of mothers and 90 (19%) of fathers quit. Among baseline non-smokers, 47 (2%) mothers and 54 (3%) fathers started smoking. Conclusions One-third of children consulting respiratory specialists in Switzerland are exposed to parental smoking. ETS exposure was strongly associated with socio-economic factors. Even after visiting a specialized clinic, most parents continued to smoke. This highlights the urgent need for stronger national smoking policies and targeted support to help these parents quit and stay smoke-free.

Unconventional T cells recognize non-peptide antigens presented by molecules other than the major histocompatibility complex (MHC) proteins. Among unconventional T cells, natural killer T (NKT) cells, which recognize CD1d-lipid complexes, mucosal-associated invariant T (MAIT) cells, which recognize MR1-metabolite complexes, and {gamma}{delta} T cells, are thoroughly studied. CD1b presents self- and mycobacterial lipids to relatively understudied T cell subsets. Like MAIT cells and type I NKT cells, CD1b-specific cells include subpopulations with conserved TCRs. Consequent to their recognition of a nearly monomorphic antigen-presenting molecule, CD1b-specific T cells might share innate-like features with MAIT, type I NKT, and {gamma}{delta} T cells. Due to their low frequency in the peripheral blood, CD1a-, CD1b-, and CD1c-specific T cells have been studied predominantly as in vitro-expanded clones, so even basic information about their native ex vivo immunophenotypes is lacking. Here, we sort and transcriptionally profile ex vivo two T cell populations that recognize CD1b presenting mycobacterial mycolipids and compare them with conventional CD4 and CD8 T cells, {gamma}{delta} T cells, NK cells, MAIT cells, and NKT cells. We show that both the invariant TCR-expressing CD4+, CD1b-GMM-specific germline encoded mycolyl-reactive (GEM) T cells, as well as the diverse TCR-expressing CD1b-GMM-specific T cells, are transcriptionally closer to conventional T cells than to the innate-like T cell populations {gamma}{delta}, MAIT and type I NKT cells. Thus, despite their recognition of non-polymorphic antigen presenting molecules, CD1b-specific T cells show adaptive rather than innate-like transcriptional features.

Group 2 innate lymphoid cells (ILC2s) regulate type 2 immune responses partly by recruiting eosinophils, but the mechanisms underlying this process remain incompletely understood. Although both ILC2s and type 2 T helper (Th2) cells are capable of expressing IL-5, a cytokine critical for recruiting eosinophils, ILC2s are more potent than Th2 cells in this process. Here, we show that the transcription factor Bhlhe40 promotes GM-CSF production in ILC2s, and Bhlhe40 expression in ILC2s is required for efficient eosinophil recruitment during both papain- and helminth-induced type 2 immune responses. However, Bhlhe40 deficiency in ILC2s had no effect on the production of classical type 2 cytokines, including IL-4, IL-5 and IL-13, despite Bhlhe40 being required for type 2 cytokine production by Th2 cells. Furthermore, in contrast to ILC2s, Th2 cells produced little GM-CSF and administration of GM-CSF rescued eosinophil recruitment in ILC2-specific Bhlhe40-deficient mice. In addition to promoting GM-CSF expression, Bhlhe40 repressed IL-10 production in ILC2s as it did in Th2 cells, particularly during chronic inflammation. Single-cell transcriptomic analyses further supported this regulatory network, and the ChIP-Seq data revealed direct binding of Bhlhe40 to the enhancer and promoter regions within the Il10 and Csf2 loci. Collectively, our findings show that Bhlhe40 exerts distinct gene regulatory functions in ILC2s and Th2 cells, and Bhlhe40 modulates the inflammatory and anti-inflammatory functions of ILC2s by promoting GM-CSF while suppressing IL-10 production.

Introduction: Idiopathic inflammatory myopathy-associated interstitial lung disease (IIM-ILD) is a major cause of morbidity and mortality. We tested whether quantitative myositis-specific autoantibodies and proteomic profiling capture biological heterogeneity and prognosis beyond categorical serology. Methods: Myositis-specific autoantibodies were quantified using the luciferase immunoprecipitation systems assay, and 184 serum proteins were measured in 226 IIM patients; 199 with higher-ILD-risk autoantibodies (Jo-1/MDA5/PL-7/PL-12/EJ), 27 with lower-ILD-risk autoantibodies (Mi-2/NXP2/TIF1{gamma}) and 35 healthy controls. We identified shared and subgroup-specific differences by comparing each subgroup with controls, then correlated quantitative autoantibody and protein levels within higher-risk subgroups. Additional analyses included pathway enrichment, unsupervised clustering, longitudinal lung-function change, and mortality. Results: Higher-ILD-risk subgroups shared interferon-responsive CXCR3 chemokine, IL-6/JAK/STAT3, and apoptosis signaling. Dominant autoantibody subgroup profiles differed: interferon/CXCR3 chemokine signaling with T-cell activation and monocyte recruitment in anti-Jo-1; proteostasis/antigen-processing and vascular/cellular stress signals in anti-MDA5; IL-6/macrophage and profibrotic signals in anti-PL-12; and apoptotic and innate immune activation with metabolic/redox-stress signals in anti-PL-7. Within higher-ILD-risk subgroups, autoantibody levels correlated with interferon-response, profibrotic, and metabolic/vascular proteins (r=0.40-0.74; nominal p<0.05). Unsupervised clustering identified four proteomic endotypes beyond autoantibody type, including an injury-stress endotype associated with worse lung function and poorer survival, and a chemokine/checkpoint-high endotype with relatively preserved lung function. Across 203 participants with 38 deaths, a weighted 10-protein score was associated with all-cause mortality (HR, 3.28; 95% CI, 2.12-5.08; p<0.001). Conclusions: Integrated quantitative autoantibodies and proteomic profiling revealed shared inflammatory biology, autoantibody-associated signatures, and an injury-stress endotype associated with poor survival in IIM-ILD, supporting risk stratification beyond categorical serology.

Cigarette smoke-induced lung inflammation is a central driver of pulmonary diseases. The limited efficacy of current anti-inflammatory agents underscores the need for structurally novel therapeutics with distinct mechanisms. We recently demonstrated that AB-free kava, a flavokavains A/B-depleted formulation from Piper methysticum containing six major kavalactones, effectively suppresses cigarette smoke-induced lung inflammation in mice. This study aims to identify the bioactive constituent(s) and elucidate underlying mechanisms. These kavalactones revealed a clear structure-activity relationship in suppressing lipopolysaccharide (LPS)-stimulated prostaglandin E2 (PGE2) production in macrophages with desmethoxyyangonin (DMY) as the most potent kavalactone whereas dihydrokavain (DHK, a structurally similar analog) with minimal activity. DMY also effectively reduced LPS-induced interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-) production while DHK was ineffective. Mechanistically, DMY, but not DHK, attenuated COX-2 induction and reduced phosphorylation of cAMP response element-binding protein (CREB). Pharmacological inhibition of protein kinase A (PKA) similarly reduced p-CREB, COX-2 and PGE2, supporting a PKA-dependent CREB/COX-2 signaling in mediating PGE2 suppression while these effects were independent of nuclear factor kappa B (NF-{kappa}B) and activator protein 1 (AP-1) signaling. Similar results were observed for DMY and DHK in attenuating cigarette smoke condensate-induced proinflammatory pathways and PGE2 production. Consistently, DMY demonstrated significant in vivo efficacy in suppressing cigarette smoke-induced lung inflammation while DHK was not effective. Interestingly, dihydromethysticin (DHM) demonstrated the greatest in vivo anti-inflammatory efficacy, although it only exhibited moderate in vitro potency, likely due to its superior bioavailability over DMY. Concordantly, cigarette smoke exposure elevated p-CREB and COX-2 expressions in mouse lungs, which were attenuated by AB-free kava and its bioactive kavalactones with the extent of suppression correlating with their in vivo anti-inflammatory efficacy. DHM effectively suppressed LPS-induced neutrophil accumulation in mouse lungs as well. Collectively, these studies identify bioactive kavalactones in AB-free kava that suppress cigarette smoke- and LPS-induced lung inflammation through the modulation of the PKA/CREB/COX-2 signaling axis, providing a foundation for developing structurally distinct anti-inflammatory agents, particularly targeting smoke-induced inflammation and associated pulmonary diseases.

The longstanding association between psychological trauma or stress and subsequent chronic inflammatory disorders is well-documented, but the mechanism by which psychopathology causes these immune changes has yet to be elucidated. We have previously reported that sympathetic innervation to lymphoid organs and beta adrenergic receptor signaling are essential for T-lymphocyte interleukin 17A (IL-17A) production and TH17 polarization, though the exact mechanistic contribution of this signaling to the development of TH17 cells remained unclear. Therefore, we hypothesized that norepinephrine (NE) is a novel and direct regulator of T-lymphocyte IL-17A expression. Herein, we indeed observed that NE regulates baseline IL-17A in vivo. We further identified a novel mechanism by which transforming growth factor beta (TGF{beta}) and NE together result in TH17 polarization and IL-17A production in CD4+ T-lymphocytes. Additionally, we found that cAMP, PKA, and CREB are induced by NE signaling, which ultimately increases CBP/p300 activity to initiate ROR{gamma}t transcription. Surprisingly, our data also demonstrate that STAT3, a transcription factor previously described as necessary for canonical TH17 polarization, is not involved in this novel pathway and may even be downregulated. Combined with bulk RNA sequencing data, our data highlight robust differences between the novel and canonical pathways to TH17 polarization. Altogether, our data reveal a novel, noncanonical mechanism that links sympathetic nervous system activity with IL-17A related inflammation, which may have significant relevance to sympathoexcitation-related disorders that stem from psychological trauma or stress.

Inflammatory bowel disease (IBD) is associated with chronic intestinal inflammation and gut microbial dysbiosis, yet effective microbiome-targeted therapeutics remain limited. Here, we investigated the anti-inflammatory and microbiome-modulating activities of metabolites isolated from Garcinia brassii, an endemic species of the Australian Wet Tropics. Five compounds, including a new natural product named garcitine, were isolated and structurally characterised. In human immune cells, garcinol and garcinia biflavonoid 1 significantly suppressed lipopolysaccharide-induced production of IL-1{beta}, IL-6, and TNF without detectable cytotoxicity, while parvifoliol F selectively inhibited IL-1{beta} release. Therapeutic efficacy was further evaluated in a TNBS-induced murine colitis model, where garcinia biflavonoid 1 and parvifoliol F significantly reduced colonic inflammation and improved histopathological outcomes. 16S rRNA sequencing demonstrated that both compounds restored gut microbial homeostasis by reversing colitis-associated dysbiosis and reducing inflammation-associated microbial signatures. Functional pathway prediction further suggested suppression of pro-inflammatory microbial metabolic pathways following treatment. Together, these findings demonstrate that Garcinia-derived metabolites alleviate experimental colitis through coordinated immunomodulatory and microbiome-reprogramming mechanisms and identify garcinia biflavonoid 1 and parvifoliol F as promising candidates for microbiome-targeted IBD therapeutics.

Systemic autoimmune connective tissue diseases (CTDs) are characterized by anti-nuclear antibodies, shared HLA-associated genetic risk, and frequent disease overlap, suggesting a central role for CD4+ T cells in pathogenesis. However, defining disease-driving CD4+ T-cell responses remains challenging due to their localization within lymphoid and affected tissues and the lack of approaches linking these responses to circulating counterparts. We combined [18F]-labeled thymidine PET/CT-guided tissue sampling, ex vivo antigen stimulation, and single-cell multiomics to characterize CD4+ T-cell responses in blood, PET-avid locoregional lymph nodes (LNs), and disease-affected tissues from patients with the immunologically distinct CTDs systemic sclerosis and Sjogren's disease. PET-avid LNs from both diseases exhibited enhanced adaptive immune activity and contained an expanded population of interferon-stimulated gene (ISG)-expressing TRAIL+ CD4+ T cells. In Sjogren's disease, active LNs and affected tissues harbored diverse effector CD4+ T-cell populations, including follicular and peripheral helper T cells and Th2/Th17 cells. In contrast, systemic sclerosis tissues lacked effector CD4+ T cells, while active LNs were enriched for naive, regulatory, and TRAIL+ ISG CD4+ T cells. Antigen stimulation of peripheral blood mononuclear cells enriched for expanded effector CD4+ T-cell populations that shared activation profiles and clonal relationships with cells in LNs and affected tissues, many representing autoreactive antigen-specific T cells. TRAIL+ CD4+ T cells suppressed effector T-cell differentiation, autoreactive plasma cell generation, and autoantibody production in vitro, identifying a previously unrecognized immunoregulatory population. Together, this workflow enables comprehensive characterization of pathogenic and regulatory CD4+ T-cell responses across CTDs.

Despite known carcinogenic properties, indoor tanning remains popular among young adults and may contribute to early-onset melanoma. Our study aims to compare early-onset melanoma incidence by state availability of tanning beds. We analyzed population-based melanoma incidence data (2019-2023) from the National Program of Cancer Registries and calculated Incidence Rate Ratios (IRR) using verified state-level quintiles of tanning bed availability. Overall, in the Midwest/South regions, melanoma incidence increased with greater tanning-bed availability, from 8.7 cases per 100,000 population in Quintile 1 to 14.8 cases per 100,000 population in Quintile 5 (IRR = 1.69; CI = 1.65-1.74). No such relationship was found in the Northeast/West regions. In conclusion, we found that in Southern and Midwest states, increased availability of tanning beds was associated with higher early-onset melanoma in non-Hispanic White males and females, in both metro and non-metro counties. Policies which reduce tanning bed availability in high utilization regions may have potential to reduce early-onset melanoma.