InVivoMAb anti-mouse IL-4

Adoptive cell therapy (ACT) relies on durable and functional T cells to mediate tumor clearance. Th9 cells are a metabolically fit CD4+ T cell subset with strong persistence but limited cytotoxicity. Here, we identified endomelipeptide A (EpA), a cyclic peptide isolated from Ganoderma lucidum-associated endophytic fungi, as a potent enhancer of Th9 cell differentiation. EpA promoted a cytotoxic Th9 phenotype with enhanced mitochondrial function and metabolic fitness. Mechanistically, EpA dually targeted ZAP70 and SREBP1, coupling T cell receptor signaling activation with lipid metabolism suppression. EpA-treated Th9 cells mediated robust, CD8+ T cell-dependent tumor control and enhanced the efficacy of human Th9 CAR T cell therapy in vivo. These findings establish EpA as a distinct cyclic peptide that reprograms Th9 cells and provides a potential approach to boost ACT efficacy.

CCR6 is a G-protein-coupled receptor that binds to its ligand CCL20. Th17 and Foxp3+CD4+ T cells express CCR6, enabling their migration to inflamed tissues with unique metabolic environments. The factors that regulate their metabolic adaptation and functional roles in these tissues remain unclear. Using inflammatory bowel disease patient samples and experimental colitis models in mice, we demonstrated that the intrinsic signaling of CCL20-CCR6 in CD4+ T cells promotes the differentiation of inflammatory Th1-like Th17 cells (T-bet+RORγt+) during colitis. This signaling induces the rapamycin-sensitive phosphorylation of PI3K, Akt, mTORC1, and STAT3 in a CCR6-dependent manner. RNA-seq and proteomics analysis revealed that the addition of CCL20 during Th17 differentiation affects several metabolic pathways, including energy metabolism. CCL20 significantly increased glycolysis and inhibited oxidative phosphorylation, thereby driving the differentiation of pathogenic Th17 cells. Our findings suggest that alterations in CCR6-induced changes in Th17 metabolism offer an interesting therapeutic target for gut inflammation and autoimmunity.

The AMPA receptor (AMPAR) is an ionotropic glutamate receptor that is essential for neuronal communication, yet its role in the immune system remains poorly understood. Here, using a CD4Cre selective deletion mouse model, we provide the first functional characterization of AMPAR deficient T cells. We demonstrate that AMPAR deletion in T cells significantly protects against severe paralysis in an experimental autoimmune encephalomyelitis (EAE) model, and this protection is associated with increased regulatory T cell (Treg) presence within the spinal cord. In vitro studies reveal that the deletion of the AMPAR intrinsically promotes Treg generation. Mechanistically, AMPAR deletion increases IL2 signaling and activates the mTORC1 pathway, supporting Treg development and function. These novel findings suggest that a function of the AMPAR in CD4 T cells is to limit immune suppression by restricting Treg differentiation. Targeting AMPARs on T cells could offer a novel therapeutic approach for the treatment of autoimmune disease.

Antibiotics influence both gut microbial composition and immune regulation, but the detailed mechanisms are still undefined. Shifts in the microbiome caused by antibiotic exposure can modulate immune activity through various pathways. Therefore, we aimed to explore how antibiotics affect immune-inflammation by regulating Th17 cells through the gut microbiota of mice with experimental autoimmune prostatitis (EAP). Antibiotic-driven shifts in gut microbial communities and metabolite profiling in EAP mice were performed by integrating 16S rRNA sequencing with mass spectrometry-driven metabolomic analysis. Antibiotic cocktail (ABX) therapy mitigated EAP, modified the gut microbiome composition, and influenced bile acid metabolism. Fecal microbiota transplantation (FMT) using microbiota from ABX-treated feces into EAP mice effectively altered gut microbiome composition and alleviated disease symptoms, indicating that microbiome intervention reduces autoimmune inflammation and decreases deoxycholic acid (DCA) in mice. Subsequent experiments demonstrated that DCA suppresses farnesol X receptor (FXR) expression which can inhibit the NLRP3‒ IL17A axis, thus promoting Th17 cell development and exacerbating inflammatory cell infiltration of the prostate. Our initial clinical examination of patients with prostatitis and antibiotic treatment indicated that bile acid metabolism and Th17 cell development are affected by antibiotic therapy. This work revealed that antibiotic-induced gut microbiota dysbiosis decreases the bile acid metabolite DCA, further restraining Th17 cell differentiation via the FXR‒NLRP3 axis to alleviate autoimmune prostatitis. Our results reveal new perspectives regarding the interconnected dynamics of antibiotics, gut microbiota, bile acid metabolism, and immune regulation, with potential relevance for therapies targeting immune-mediated diseases.

House dust mite (HDM) is a common environmental aeroallergen strongly associated with asthma and chronic airway inflammation. While HDM exposure is known to induce T helper 2 (Th2)-mediated eosinophilic inflammation, its chronic effects on interleukin-1β (IL-1β)-associated neutrophilic inflammation remain poorly understood. This study used single-cell RNA sequencing (scRNA-seq) to investigate how chronic HDM exposure remodels the murine lung immune microenvironment, with a focus on the role of IL-1β in shaping HDM-driven immune responses.

Osteoarthritis (OA) pathogenesis is profoundly influenced by dysregulated immune dynamics, where persistent interleukin-17 (IL-17)/T helper 17 (Th17) cell mediated inflammation coordinates with failed regenerative processes to perpetuate joint destruction. Here, we unveil the role of myeloid-derived suppressor cells (MDSCs) as dual-phase regulators that paradoxically orchestrate both inflammatory escalation and tissue repair in OA progression. Intra-articular administration of MDSCs in OA mice amplified IL-17 dependent inflammatory cascades and chemokine-driven leukocyte recruitment, revealing a context-dependent pro-inflammatory phenotype. Unexpectedly, MDSC depletion failed to attenuate joint damage, implying their indispensable yet multifaceted role in OA pathogenesis. Mechanistically, MDSCs exhibited functional plasticity by upregulating arginase-1 to polarize M2 macrophages, fostering a regenerative niche alongside their inflammatory activity. To resolve this duality, we developed a bio-responsive hydrogel-microsphere system integrating transforming growth factor β1 (TGF-β1) and interleukin-1 β1 antibody (anti-IL-1β) loaded mesoporous silica nanoparticles (MSNs). This spatiotemporally controlled platform selectively suppressed MDSC-mediated Th17 cell expansion while harnessing their intrinsic capacity to drive M2 macrophage polarization and chondrogenesis. The resultant shift from a pro-inflammatory to pro-regenerative microenvironment significantly attenuated cartilage erosion and restored joint integrity in OA models. Our findings redefine MDSCs as bifunctional immune orchestrators in OA and establish precision biomaterial guided immune decoding as a paradigm-shifting therapeutic strategy. By engineering MDSCs plasticity through antagonistic cytokine delivery, this work provides a blueprint for microenvironment remodeling in degenerative joint diseases.

The mechanism of the association of S. aureus skin colonization with food allergy in atopic dermatitis (AD) is unknown. Interleukin-4 (IL-4) plays an important role in food allergy. We found elevated serum IL-4 concentrations in AD patients with S. aureus skin colonization and food allergy. Using an AD mouse model, we demonstrated that epicutaneous application of antigen together with superantigen-producing S. aureus, or staphylococcal enterotoxin B (SEB), caused a heightened systemic antigen-specific T helper-2 (Th2) response and elevated serum IL-4 concentrations. T cell-derived IL-4 acted on intestinal epithelial cells to enhance intestinal permeability and anaphylaxis to enteral antigen challenge. CD40-dependent SEB binding to keratinocytes triggered IL-33 release, which caused T cells to produce IL-3 that elicited a basophil influx in skin-draining lymph nodes (dLNs). Basophil-derived IL-4 augmented Th2 cell polarization by antigen-bearing dendritic cells from skin dLNs. These results suggest therapeutic interventions that might attenuate food allergy in AD patients.

A20, encoded by the TNFAIP3 gene, is a protein linked to Crohn's disease and celiac disease in humans. We now find that mice expressing point mutations in A20's M1-ubiquitin-binding zinc finger 7 (ZF7) motif spontaneously develop proximal enteritis that requires both luminal microbes and T cells. Cellular and transcriptomic profiling reveals expansion of Th17 cells and exuberant expression of IL-17A and IL-22 in intestinal lamina propria of A20ZF7 mice. While deletion of IL-17A from A20ZF7/ZF7 mice exacerbates enteritis, deletion of IL-22 abrogates intestinal epithelial cell hyperproliferation, barrier dysfunction, and alarmin expression. Colonization of adult germ-free mice with microbiota from adult WT specific pathogen-free mice drives duodenal IL-22 expression and duodenitis. A20ZF7/ZF7 Th17 cells autonomously express more RORγt and IL-22 after differentiation in vitro. ATAC sequencing identified an enhancer region upstream of the Il22 gene, and this enhancer demonstrated increased activating histone acetylation coupled with exaggerated Il22 transcription in A20ZF7/ZF7 T cells. Acute inhibition of RORγt normalized histone acetylation at this enhancer. Finally, CRISPR/Cas9-mediated ablation of A20ZF7 in human T cells increases RORγt expression and IL22 transcription. These studies link A20's M1-ubiquitin binding function with RORγt expression, expansion of Th17 cells, and epigenetic activation of IL-22-driven enteritis.

Although extranuclear histones have been identified for a long time, their role in lymphocytes, particularly cytoplasmic histones, remains elusive. In this study, we conducted a visual and quantitative analysis of cytoplasmic histones in CD4+ T cells and discovered that effector CD4+ T cells contain higher levels of cytoplasmic histones compared to naïve T cells. We observed a significant increase in cytoplasmic histones following T cell receptor (TCR) activation, with further elevation during the differentiation of Th1 and Th17 cells. Interestingly, double-stranded RNA (dsRNA) specifically enhanced cytoplasmic histones in Th17, but not in Th1 cells. Additionally, we confirmed that cytoplasmic H2B-positive Th17 cells exhibited increased expression of inflammatory molecules, including pro-inflammatory cytokines. Data are available via ProteomeXchange with identifier PXD063335. Importantly, CD4+ T cells from peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) presented elevated levels of cytoplasmic histones. These findings define cytoplasmic histones as markers of proinflammatory CD4+ T cells and suggest their potential as biomarkers for autoimmune disease.

Nonalcoholic fatty liver disease (NAFLD) has posed a huge threat to public health globally, but there are currently no approved drugs available. Growing evidence has proved the close association between increased Th17 cells and NAFLD progression. Interleukin-4 induced protein 1 (IL4I1), an amino acid oxidase secreted by immune cells, was reported to regulate the Th17 cells, but its exact role in NAFLD progression has not been fully explained yet. We found that IL4I1 was highly expressed in the liver of C57BL/6J mice with NAFLD induced by an 8-weeks western diet. To explore the IL4I1's effect, mice were injected with AAV8 encoding IL4I1 1 week before western diet administration. The results showed that IL4I1 overexpression inhibited the NAFLD progression, demonstrated by relieved liver damage and lipid accumulation. The underlying mechanism in which IL4I1 acts on NAFLD might be attributed to the inactivated AKT/forkhead box protein O1 (FOXO1) signaling pathway-mediated decrease of Th17 cells in liver tissues. Subsequently, by culturing naive CD4+ T cells isolated from the spleen of mice in Th17 cell-polarizing conditions, we determined that IL4I1 overexpression inhibited Th17 cell differentiation by inactivating the AKT/FOXO1 pathway, whereas its knockdown exhibited opposite effects. Further, the AKT activator SC79 reversed the effect of IL4I1 overexpression on Th17 cell differentiation. Collectively, our study supports that compensatory upregulation of IL4I1 protects against liver damage and lipid accumulation in NAFLD progression, partially by inhibiting the activated AKT/FOXO1 signaling pathway-induced Th17 cell differentiation.

Small extracellular vesicles (sEVs) released from tumors recruit nociceptor neurons to the tumor bed. Here, we found that ablating these neurons in mouse models of head and neck carcinoma and melanoma reduced the infiltration of myeloid-derived suppressor cells (MDSCs). Moreover, sEV-deficient tumors failed to develop in mice lacking nociceptor neurons. We investigated the interplay between tumor-infiltrating nociceptors and immune cells in head and neck squamous cell carcinoma (HNSCC) and melanoma. Upon exposure to cancer-derived sEVs, mouse dorsal root ganglion (DRG) neurons secreted increased amounts of substance P, IL-6, and injury-associated neuronal markers. Patient-derived sEVs sensitized DRG neurons to capsaicin, implying enhanced nociceptor responsiveness. Furthermore, nociceptors cultured with sEVs induced an immunosuppressed state in CD8+ T cells. Incubation with conditioned medium from cocultures of neurons and cancer cells resulted in increased expression of markers of MDSCs and suppressive function in primary bone marrow cells, and the combination of neuron-conditioned medium and cancer sEVs promoted checkpoint receptor expression on T cells. Together, these findings reveal that nociceptor neurons facilitate CD8+ T cell exhaustion and bolster MDSC infiltration into HNSCC and melanoma. Consequently, targeting nociceptors may provide a strategy to disrupt detrimental neuroimmune cross-talk in cancer and potentiate antitumor immunity.

The differentiation and suppressive functions of regulatory CD4 T cells (Tregs) are supported by a broad array of metabolic changes, providing potential therapeutic targets for immune modulation. In this study, we focused on the regulatory role of glycolytic enzymes in Tregs and identified phosphoglycerate mutase (PGAM) as being differentially overexpressed in Tregs and associated with a highly suppressive phenotype. Pharmacologic or genetic inhibition of PGAM reduced Treg differentiation and suppressive function while reciprocally inducing markers of a pro-inflammatory, T helper 17 (Th17)-like state. The regulatory role of PGAM was dependent on the contribution of 3-phosphoglycerate (3 PG), the PGAM substrate, to de novo serine synthesis. Blocking de novo serine synthesis from 3 PG reversed the effect of PGAM inhibition on Treg polarization, while exogenous serine directly inhibited Treg polarization. Additionally, altering serine levels in vivo with a serine/glycine-free diet increased peripheral Tregs and attenuated autoimmunity in a murine model of multiple sclerosis. Mechanistically, we found that serine limits Treg polarization by contributing to one-carbon metabolism and methylation of Treg-associated genes. Inhibiting one-carbon metabolism increased Treg polarization and suppressive function both in vitro and in vivo in a murine model of autoimmune colitis. Our study identifies a novel physiologic role for PGAM and highlights the metabolic interconnectivity between glycolysis, serine synthesis, one-carbon metabolism, and epigenetic regulation of Treg differentiation and suppressive function.

Intermittent fasting (IF), particularly time-restricted feeding (TRF), is increasingly popular has gained popularity for weight loss, yet management, but its effects impact on gut health remain unclear. Remains inadequately understood. This study explores how investigated the effects of TRF effects on intestinal health and explored the underlying mechanisms.

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a frequently encountered disorder characterized by voiding symptoms and pelvic or perineal pain. Proinflammatory T helper 17 (Th17) cells are essential for triggering the development of CP/CPPS. High-salt diet (HSD) consumption has been found to cause an accumulation of sodium chloride in peripheral organs, inducing autoimmune responses via the Th17 cell axis. It is currently unknown whether HSD affects the etiology and course of CP/CPPS.

The liver is an important metastatic organ that contains many innate immune cells, yet little is known about their role in anti-metastatic defense. We investigated how invariant natural killer T (iNKT) cells influence colorectal cancer-derived liver metastasis using different models in immunocompetent mice. We found that hepatic iNKT cells promote metastasis by creating a supportive niche for disseminated cancer cells. Mechanistically, iNKT cells respond to disseminating cancer cells by producing the fibrogenic cytokines interleukin-4 (IL-4) and IL-13 in a T cell receptor-independent manner. Selective abrogation of IL-4 and IL-13 sensing in hepatic stellate cells prevented their transdifferentiation into extracellular matrix-producing myofibroblasts, which hindered metastatic outgrowth of disseminated cancer cells. This study highlights a novel tumor-promoting axis driven by iNKT cells in the initial stages of metastasis.

Chronic prostatitis is a common urological disorder in young and middle-aged men, characterized by frequent relapses and an unknown etiology. We investigated the potential function of insulin-like growth factor 1 (IGF1) -related ligands in chronic prostatitis in the current study.

In clinical practice, repairing osteochondral defects (OCDs) is challenging because of the complex cartilage/subchondral bone structure and intricate immunological microenvironment. Here, we identify the crucial role of adaptive immunity dysfunction by revealing that an increase of T helper 17 (Th17) cells exacerbated osteochondral tissue degradation via its pro-inflammatory cytokine interleukin-17 (IL-17) in the early-stage OCDs. Next, we leveraged this adaptive immunity mechanism and combined it with regenerative signals to develop a multifunctional hydrogel system capable of simultaneously tackling immune dysfunction and regenerative deficiency. Rapid IL-4 release from the methacrylated hyaluronic acid (HAMA) hydrogel exerts a potent immunomodulatory effect by inhibiting the differentiation and function of Th17 cells. Moreover, transforming growth factor-beta1 anchored on methacrylated hyaluronic acid and heparin (HAMA@HepMA) microparticles provides sustained regenerative signals, which synergistically transform the pro-inflammatory microenvironment into a pro-regenerative niche for enhanced OCDs healing. Our study suggests that targeting specific immune pathways can significantly enhance the efficacy of regenerative strategies, paving the way for innovative treatments in orthopedic medicine.

Rocaglamide (Roc-A), a natural phytochemical isolated from Aglaia species, is known to exert anticancer effects. Allergic inflammation can enhance the tumorigenic potential of cancer cells. We hypothesized that Roc-A could regulate allergic inflammation. Roc-A prevented an antigen from increasing the hallmarks of allergic reactions in vitro. Roc-A suppressed passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis (PSA). RNA sequencing analysis showed that Roc-A prevented the antigen from increasing the expression of IL-4 in RBL2H3 cells. Roc-A also prevented the antigen from increasing the expression of interleukin-4 receptor (IL-4R). Roc-A was found to form a hydrogen-bonding network with residues N92 and L64 of IL-4R in a molecular docking simulation. Roc-A prevented the antigen from inducing the binding of IL-4R to JAK1. Chromatin immunoprecipitation (ChIP) assays showed that C-Jun could bind to promoter sequences of IL-4 and IL-4R. Mouse recombinant IL-4 protein increased β-hexosaminidase activity, IL-4R expression, and the hallmarks of allergic inflammation in the antigen-independent manner. Mouse recombinant IL-4 protein increased the expressions of CD163 and arghinase-1 and markers of M2 macrophages, but decreased the expression of iNOS, a marker of M1 macrophages in lung macrophages. Roc-A regulated the effects of a culture medium of antigen-stimulated RBL2H3 cells on the expressions of iNOS and arginase-1 in RAW264.7 macrophages. The blocking of IL-4 or downregulation of IL-4R exerted negative effects on the hallmarks of allergic reactions in vitro. The blocking of IL-4 or downregulation of IL-4R also exerted negative effects on PCA, and the downregulation of IL-4R exerted negative effects on PSA. An miR-34a mimic exerted negative effects on allergic reactions in vitro. The downregulation of IL-4R prevented the antigen from decreasing the expression of miR-34a in RBL2H3 cells. We identified chemicals that could bind to IL-4R via molecular docking analysis. The IL-4R docking chemical 1536801 prevented the antigen from increasing β-hexosaminidase activity and the hallmarks of allergic reactions. The IL-4R docking chemical 1536801 also exerted a negative effect on PCA. TargetScan analysis predicted miR-34a as a negative regulator of IL-4R. We found that the anti-allergic effect of Roc-A and its mechanisms were associated with miR-34a. Taken together, our results show that understanding IL-4R-mediated allergic reactions can provide clues for the development of anti-allergy therapeutics.