InVivoMAb anti-mouse/rat IL-1β

Metabolic-inflammatory crosstalk orchestrates muscle repair. Although pyroptosis typically aggravates sterile injury, we demonstrated that GSDME-dependent pyroptotic signaling associated with recruited myeloid cells paradoxically supported regeneration. GSDME expression was induced in post-surgical human muscle injury and murine damage models. Gsdme deficiency delayed functional recovery and exacerbated injury-induced myosteatosis, a pathological form of intramuscular ectopic fat deposition. Time-series and single-cell RNA-sequencing analyses revealed that GSDME loss shifted the transcriptional program from oxidative metabolism toward lipid storage and adipogenesis. Lipidomics confirmed aberrant accumulation of triacylglycerols and sphingolipids in Gsdme-deficient muscle. Single-cell profiling further identified divergent fibro-adipogenic progenitors (FAPs) states skewed toward adipogenesis, accompanied by impaired expansion of restorative Lyve1⁺Cd163⁺Txnip⁺ tissue-resident macrophages (TRMs)-validated by multiplex flow cytometry. Blocking CCR2-dependent monocyte recruitment produced regenerative defects comparable to those caused by Gsdme deficiency. Myeloid-specific Gsdme reintroduction rescued TRM expansion and function, curbed FAP adipogenic reprogramming, whereas FAP-specific expression proved ineffective. Mechanistically, IL-18 downstream of GSDME-dependent signaling engaged KLF4/JUN signaling in TRMs, sustaining their reparative and lipid-clearing capacity. This GSDME-IL-18-TRMs axis was compromised in aged muscle, yet exogenous IL-18 reversed myosteatosis and accelerated regeneration. Together, these findings suggest that GSDME-dependent pyroptotic signaling can act as a metabolic checkpoint that sustains TRM-driven lipid homeostasis to support muscle regeneration.

Discovering more targets is of great importance for developing alternative interventions for tumor therapy. The roles of transmembrane protein 175 (TMEM175) in neurodegeneration diseases have been reported, however its functions in tumor immune surveillance are not known. We show that TMEM175 conditional knockout in macrophages inhibits the tumor growth and metastasis through promoting the anti-tumor immunity in the tumor microenvironment (TME), including elevated M1-like polarization, reduced M2-like polarization, and facilitated recruitment and activation of T cells and nature killer cells (NKs). The anti-tumor immunity is abrogated by caspase-1 inhibitor VX-765, anti-IL-1β, and anti-IL-18. Tmem175-/- bone marrow-derived macrophages (BMDMs) show enhanced tumor antigen cross-presentation that is further strengthened by IL-1β and IL-18. NLRP3 is robustly elicited in Tmem175-/- BMDMs by the tumor cell debris through lysosomal permeabilization and cathepsin B leakage. Finally, Tmem175-/- mice are more responsive to anti-PD-1. Our works implies TMEM175 to be a potential target for immunotherapy.

Clonal hematopoiesis driven by Tet2 deficiency in myeloid cells (TetΔMye) is prevalent in elderly individuals; however, the role of Tet2ΔMye in liver fibrosis pathogenesis remains elusive. In this study, we demonstrated that Tet2-deficient monocyte-derived macrophages (MDMs) promoted cellular expansion and elevated C-C motif chemokine ligand 2/8 (Ccl2/8) secretion by stabilizing their mRNAs through 5hmC-mediated alterations in RNA-protein interactions. These chemokines engaged with the upregulated C-C motif chemokine receptor (Ccr2/3) on Tet2-/- monocytes, forming a positive feedback loop that amplified pro-inflammatory MDMs (pMDMs) accumulation in liver. Tet2-/- pMDMs activated hepatic stellate cells through IL-6, driving extracellular matrix deposition and fibrotic progression. Pharmacological inhibition of Ccl2/Ccl8 with Bindarit attenuated MDMs accumulation and liver fibrosis, whereas combined therapy with Bindarit and IL-6 neutralization synergistically suppressed liver fibrosis in Tet2ΔMye mice and aged chimeric models recapitulating Tet2ΔMye-related myeloid hematopoiesis. These findings present the mechanism that Tet2ΔMye aggravates liver fibrosis and highlight MDMs depletion plus IL-6 neutralization as a promising therapy for liver fibrosis in patients with Tet2ΔMye-related myeloid hematopoiesis.

Background: Lung metastasis is a leading cause of breast cancer (BC)-related mortality, driven by the immunosuppressive traits of the metastatic tumor microenvironment. However, the mechanisms underlying cell-cell crosstalk in shaping immune evasion within the metastatic niche remain poorly defined. Neutrophil extracellular traps (NETs) and their associated proteins, such as cathelicidin, have emerged as key mediators of metastatic regulation in cancer. Here, we aimed to decipher the interaction between a neutrophil subset characterized by high expression of lymphocyte antigen 6 complex locus g (Ly6ghigh) and cluster of differentiation 8-positive T lymphocytes (CD8+ T cells), mediated via cathelicidin embedded in NETs, as well as their synergistic mechanism and cooperative role in promoting lung metastasis of BC. Methods: We characterized neutrophil heterogeneity and functional dynamics by performing single-cell RNA sequencing and flow cytometry on lung tissues derived from murine models of BC lung metastasis. We utilized cathelicidin-related antimicrobial peptide (Cramp) knockout mice to dissect the role of cathelicidin in NETs. The spatial colocalization of apoptotic CD8+ T cells and NETs was analyzed using multiplex immunofluorescence, and the molecular interactions were probed by protein binding assays. Results: Neutrophils in the lung metastatic niche were classified into 2 subsets based on the Ly6g expression: Ly6ghigh and Ly6glow neutrophils. Ly6glow neutrophils, which were recruited in the macrometastatic stage, exhibited myeloid-derived suppressor cell-like characteristics. Notably, Ly6ghigh neutrophils induced CD8+ T cell apoptosis through NET formation, with apoptotic CD8+ T cells spatially clustered within NET-rich areas. Mechanistically, NET-derived cathelicidin (Cramp in mice) directly bound to mitochondrial adenine nucleotide translocator 1 (Ant1) in CD8+ T cells, triggering conformational changes and complex formation with voltage-dependent anion channel 1 (Vdac1). These events resulted in the opening of the mitochondrial permeability transition pore and loss of mitochondrial membrane potential. Conclusions: Our study demonstrates that Ly6ghigh neutrophils play a critical role in immunosuppression and immune evasion through NET-induced apoptosis of CD8+ T cells. These findings underscore the importance of NETs and cathelicidin in BC lung metastasis, suggesting their potential as therapeutic targets in restoring antitumor immunity and in preventing metastatic progression.

Spatiotemporally-controllable regulation of innate immunity in lymph node remains a critical challenge to implement effective cancer vaccination. Here we report an ultrasound-activatable strategy to precisely stimulate innate immunity activation in vivo. Mechanistically, ultrasound-triggered mechanical and oxidative forces synchronously activate innate immune pathways in antigen-presenting cells via calcium ion influx and mitochondria DNA release. We next design a polypeptide sono-adjuvant (SONA) library with adjustable physicochemical properties for lymph node-targeting delivery. The top-performed SONA specifically activates robust and durable innate immune responses in lymph node upon localized ultrasound stimulation. The combination of SONA-based vaccine with ultrasound stimulation induces about 3.0-fold higher antigen-specific T cell responses than conventional adjuvant-based vaccines. Moreover, in syngeneic mouse models of orthotopic breast and liver tumors, the combination of SONA-based neoantigen vaccine with ultrasound stimulation markedly boosts immune checkpoint blockade therapy to suppress tumor growth and distant metastasis. Collectively, the polypeptide sono-adjuvant offers great promise for precise regulation of innate immunity and cancer vaccine therapy.

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 effectiveness of chemoimmunotherapy for hepatocellular carcinoma (HCC) is hindered by the weak immunogenicity of chemotherapy-induced immunogenic cell death (ICD). This limitation primarily stems from the insufficient activation of the extracellular adenosine triphosphate (eATP)/P2X7 purinergic receptor (P2X7R)/NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome pathway in dendritic cells (DCs). To address this challenge, we designed ivermectin-MnO2 nanocomplexes (IMNs) as P2X7R-targeted nanoimmunoamplifiers to enhance the immunogenicity of chemotherapy-induced ICD. The ivermectin component of IMN enhanced liposomal doxorubicin (LD)-induced ICD and increased P2X7R sensitivity to eATP. Additionally, the MnO2 component of IMN alleviated tumor hypoxia and down-regulated CD39/CD73 expression, thereby preventing eATP degradation. These combined strategies robustly activated the eATP/P2X7R/NLRP3 inflammasome cascade in DCs, eliciting a potent antitumor immune response. In combination with anti-PD-L1 antibody and LD, IMN effectively inhibited tumor growth in orthotopic, subcutaneous, and metastatic HCC mouse models. Our study underscores the crucial role of IMN in amplifying the NLRP3 inflammasome cascade in DCs during ICD, presenting a promising strategy to enhance the efficacy of HCC chemoimmunotherapy.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe conditions with high morbidity and mortality with limited effective therapies. Neuroimmune interactions play a critical role in lung homeostasis, but it remains unclear if specific brain regions regulate lung inflammation. Here, we perform anatomical tracing, chemogenetic modulation, and pharmacological interventions in male mice and identify a neural circuit from corticotropin-releasing hormone neurons in the paraventricular nucleus of the hypothalamus (CRHPVN neurons) to the lung. The activation of these neurons protects mice from ALI and promotes survival, reduces neutrophil infiltration and effector functions in the lung, whereas inhibiting CRHPVN neurons worsens ALI. The protective effect is mediated by increased sympathetic nervous activity, with locally released norepinephrine modulating neutrophil functions via β2-AR-β-arrestin2 signaling to inhibit the NF-κB pathway. These findings uncover a brain-lung neural circuit that modulates immune responses during ALI, offering a potential therapeutic target for ALI and ARDS.

High fat diet (HFD)-induced obesity increases the risk and severity of psoriasis. However, the immunoregulatory effects of different HFDs on psoriasis pathogenesis remains poorly understood. Here, mimicking human dietary fat profiles, four HFDs-saturated, monounsaturated, omega-6, and omega-3 fats-were designed and used to induce obesity in mice. Despite comparable obesity levels across groups, only the saturated HFD exacerbated imiquimod (IMQ)-induced psoriasis. This exacerbation correlated with elevated levels of IL-1β-producing macrophages, IL-17A-producing γδ T cells, and neutrophils within psoriatic lesions. Mechanistically, saturated fatty acids (FAs) promoted IL-1β/IL-17A signaling via fatty acid-binding protein 5 (FABP5)-mediated mitochondrial FA oxidation and extracellular ATP release in skin macrophages. Deletion of FABP5, either globally or specifically in macrophages, attenuated IL-1β/IL-17A signaling and alleviated IMQ-induced psoriasis. These findings identify FABP5 as a key mediator of saturated HFD-driven psoriasis via the IL-1β/IL-17 axis, offering insights into the interplay between dietary fats, obesity, and psoriasis.

In metastasis, the dynamics of tumor-immune interactions during micrometastasis remain unclear. Identifying the vulnerabilities of micrometastases before outbreaking into macrometastases can reveal therapeutic opportunities for metastasis. Here, we report a function of T cell immunoglobulin and mucin domain 3 (TIM3) in tumor cells during micrometastasis using breast cancer (BC) metastasis mouse models. TIM3 is highly upregulated in micrometastases, promoting survival, stemness, and immune escape. TIM3+ tumor cells are specifically selected during early seeding of micrometastasis. Mechanistically, TIM3 increases β-catenin/interleukin-1β (IL-1β) signaling, leading to stemness and immune-evasion by inducing immunosuppressive γδ T cells and reducing CD8 T cells during micrometastasis. Clinical data confirm increased TIM3+ tumor cells in BC metastasis and TIM3+ tumor cells as a biomarker of poor outcome in BC patients. (Neo)adjuvant TIM3 blockade reduces the metastatic seeding and incidence in preclinical models. These findings unveil a specific mechanism of micrometastasis immune-evasion and the potential use of TIM3 blockade for subclinical metastasis.

Tumor-induced systemic accumulation and polarization of neutrophils to an immunosuppressive phenotype is a potent driver of metastasis formation. Yet, how mammary tumors reprogram granulopoiesis at the molecular level and when tumor imprinting occurs during neutrophil development remains underexplored. Here, we combined single-cell, chromatin and functional analyses to unravel the tumor-driven reprogramming of granulopoiesis in the bone marrow, along with intervention studies aimed at reversing this process. We observe that mammary tumors accelerate commitment to the neutrophil lineage at the expense of lymphopoiesis and erythropoiesis without stimulating the development of a novel myeloid lineage. Moreover, tumor-directed immunosuppressive imprinting of neutrophils starts early in hematopoiesis. Treatment with anti-IL-1β normalizes tumor-induced granulopoiesis, reducing neutrophil immunosuppressive phenotype and mitigating metastatic spread. Together, these data provide molecular insights into the aberrant, tumor-driven neutrophil differentiation pathway leading to metastasis-promoting chronic inflammation and how it can be reversed to reduce metastatic spread.

Excessive inflammation and cytokine release are hallmarks of severe COVID-19. Certain programmed cell death processes can drive inflammation, however, their role in the pathogenesis of severe COVID-19 is unclear. Pyroptosis is a pro-inflammatory form of regulated cell death initiated by inflammasomes and executed by the pore-forming protein gasdermin D (GSDMD). Using an established mouse adapted SARS-CoV-2 virus and a panel of gene-targeted mice we found that deletion of the inflammasome (NLRP1/3 and the adaptor ASC) and pore forming proteins involved in pyroptosis (GSDMA/C/D/E) only marginally reduced IL-1β levels and did not impact disease outcome or viral loads. Furthermore, we found that SARS-CoV-2 infection did not trigger GSDMD activation in mouse lungs. Finally, we did not observe any difference between WT animals and mice with compound deficiencies in the pro-inflammatory initiator caspases (C1/11/12-/-). This indicates that the classical canonical and non-canonical pro-inflammatory caspases known to process and activate pro-IL-1β, pro-IL-18 and GSDMD do not substantially contribute to SARS-CoV-2 pathogenesis. However, the loss of IL-1β, but not the absence of IL-18, ameliorated disease and enhanced survival in SARS-CoV-2 infected animals compared to wildtype mice. Collectively, these findings demonstrate that IL-1β is an important factor contributing to severe SARS-CoV-2 disease, but its release was largely independent of inflammasome and pyroptotic pathways.

Oral squamous cell carcinoma (OSCC), one of the most prevalent and aggressive forms of head and neck squamous cell carcinoma, has a five-year survival rate of about 50% ~ 60%, emphasizing the urgent need for more effective therapeutic strategies. Solute carrier family 7 member 11 (SLC7A11) is overexpressed in various cancers and represents a potential therapeutic target. Sulfasalazine (SAS), a Food and Drug Administration-approved drug, is a potent inhibiter of SLC7A11. However, SAS can also increase the levels of pro-inflammatory cytokines such as IL-1β, which may suppress the immune response. Here, we investigate the effect of SAS combined with anti-IL-1β monoclonal antibody (anti-IL-1β mAb) as a novel treatment strategy for OSCC. In this study, SLC7A11 was markedly increased in OSCC tissues, and high SLC7A11 expression predicted poor prognosis. SAS treatment was shown to suppress OSCC cell proliferation and trigger ferroptosis, as evidenced by elevated reactive oxygen species, reduced glutathione and enhanced lipid peroxidation. SAS also elevated IL-1β levels, leading to T cell exhaustion. Combining SAS with anti-IL-1β mAb reversed T cell exhaustion and amplified the anti-tumor effects in vitro. In the 4-nitroquinoline-1-oxide-induced oral cancergenisis model, the combination treatment significantly inhibited oral carcinogenesis compared to monotherapy. Our results suggest that combining SAS with anti-IL-1β mAb enhances the anti-tumor efficacy against OSCC through tumor growth inhibition and immune modulation, offering a promising therapeutic strategy.

The regeneration of the enthesis remains a formidable challenge in regenerative medicine. However, key regulators underlying unsatisfactory regeneration remain poorly understood. This study reveals that the purinergic receptor P2X7 (P2X7R)/Nod-like receptor family protein 3 (NLRP3) inflammasome axis suppresses enthesis regeneration by amplifying IL-1β-mediated inflammatory cross-talk and suppressing docosatrienoic acid (DTA) metabolic cross-talk. NLRP3 inflammasomes were activated in macrophages following enthesis injury, thereby impairing the histological and functional recovery of the injured enthesis. Single-cell RNA sequencing (scRNA-seq) indicated that Nlrp3 knockout attenuated pathological inflammation and ameliorated the detrimental effects of IL-1β signaling cross-talk. Furthermore, NLRP3 inflammasomes suppressed the secretion of anti-inflammatory cytokines (IL-10 and IL-13) and DTA. The NLRP3 inflammasome-mediated secretome reduced differentiation and migration of stem cells. Neutralizing IL-1β or replenishing docosatrienoic acid accelerated enthesis regeneration. Moreover, conditional knockout of P2rx7 in myeloid cells attenuated NLRP3 inflammasome activation and facilitated enthesis regeneration. This study demonstrates that the P2X7R/NLRP3 inflammasome axis represents a promising therapeutic target for enthesis repair.

IL-1β is a principal proinflammatory cytokine underlying multiple local and systemic chronic inflammatory conditions including psoriasis, rheumatoid arthritis, inflammatory bowel disease, and type 2 diabetes. Passive immunotherapies and biologic drugs targeting IL-1β, while offering significant clinical benefit, nevertheless have limitations such as significant non-response rates, induction of anti-drug antibodies, and high costs. Here, an active immunotherapy raising antibody responses against IL-1β employing self-assembling peptide nanofibers is described. The nanofibers contain defined quantities of B-cell epitopes from IL-1β and exogenous T helper epitopes and employ the Q11 self-assembling peptide platform. Without adjuvant, the nanofibers raised durable anti-IL-1β antibody responses that inhibit IL-1β activity in vitro and in vivo. In a mouse model of imiquimod-induced psoriasis, prophylactic immunizations with the nanofibers diminished symptoms of epidermal thickening. This therapeutic effect is associated with biasing the immune response toward an anti-inflammatory IgG1/Th2 phenotype and a lowered expression of proinflammatory genes in the skin. Further, anti-IL-1β nanofibers induced therapeutic immunosuppressive CD62L+ Treg cells. This technology represents a potential alternative for passive immunotherapies and other biologics for treating chronic inflammatory conditions.

Inducing ferroptosis in tumor cells is emerging as a strategy for treating malignancies that are refractory to traditional treatment modalities. However, the consequences of ferroptosis of immune cells in the tumor microenvironment need to be better understood in order to realize the potential of this approach. In this study, we discovered that neutrophils in chemoresistant breast cancer are highly sensitive to ferroptosis. Reduction of the acyltransferase MOAT1 in chemoresistance-associated neutrophils induced phospholipid reprogramming, switching the preference from monounsaturated fatty acids to polyunsaturated fatty acids, which increased their susceptibility to ferroptosis. Ferroptotic neutrophils secreted PGE2, IDO, and oxidized lipids that suppressed the proliferation and cytotoxicity of antitumor CD8+ T cells. Furthermore, neutrophil ferroptosis was closely related to a distinct subset of IL1β+CXCL3+CD4+ (Fer-CD4) T lymphocytes, which were enriched in chemoresistant tumors. Fer-CD4 T cells orchestrated neutrophil ferroptosis by modulating MOAT1 expression via IL1β/IL1R1/NF-κB signaling. Moreover, Fer-CD4 T cells secreted CXCL3, IL8, and S100A9 to replenish the neutrophil pool in the tumor microenvironment. Ferroptotic neutrophils in turn fostered Fer-CD4 T-cell differentiation. In spontaneous tumorigenesis mouse models, targeting IL1β+ CD4+ T cells or IL1R1+ neutrophils broke the cross-talk, restraining neutrophil ferroptosis, enhancing antitumor immunity, and overcoming chemoresistance. Overall, these findings uncover the role of neutrophil ferroptosis in shaping the immune landscape and propose appealing targets for restoring immunosurveillance and chemosensitivity in breast cancer. Significance: In chemoresistant breast cancer, IL1β+CXCL3+CD4+ T cells mediate neutrophil ferroptosis that suppresses antitumor immunity, indicating that interfering with this intercellular cross-talk could be an attractive strategy to reverse chemoresistance.

Age is a major risk factor for cancer, but how aging impacts tumor control remains unclear. In this study, we establish that aging of the immune system, regardless of the age of the stroma and tumor, drives lung cancer progression. Hematopoietic aging enhances emergency myelopoiesis, resulting in the local accumulation of myeloid progenitor-like cells in lung tumors. These cells are a major source of interleukin (IL)-1⍺, which drives the enhanced myeloid response. The age-associated decline of DNA methyltransferase 3A enhances IL-1⍺ production, and disrupting IL-1 receptor 1 signaling early during tumor development normalized myelopoiesis and slowed the growth of lung, colonic, and pancreatic tumors. In human tumors, we identified an enrichment for IL-1⍺-expressing monocyte-derived macrophages linked to age, poorer survival, and recurrence, unraveling how aging promotes cancer and offering actionable therapeutic strategies.

Oral squamous cell carcinoma (OSCC) remains a major death cause in head and neck cancers, but the exact pathogenesis mechanisms of OSCC are largely unclear.

Aging progresses through the interaction of metabolic processes, including changes in the immune and endocrine systems. Glucocorticoids (GCs), which are regulated by the hypothalamic-pituitary-adrenal (HPA) axis, play an important role in regulating metabolism and immune responses. However, the age-related changes in the secretion mechanisms of GCs remain elusive. Here, we found that corticosterone (CORT) secretion follows a circadian rhythm in young mice, whereas it oversecreted throughout the day in aged mice >18 months old, resulting in the disappearance of diurnal variation. Furthermore, senescent cells progressively accumulated in the zF of the adrenal gland as mice aged beyond 18 months. This accumulation was accompanied by an increase in the number of Ad4BP/SF1 (SF1), a key transcription factor, strongly expressing cells (SF1-high positive: HP). Removal of senescent cells with senolytics, dasatinib, and quercetin resulted in the reduction of the number of SF1-HP cells and recovery of CORT diurnal oscillation in 24-month-old mice. Similarly, administration of a neutralizing antibody against IL1β, which was found to be strongly expressed in the adrenocortical cells of the zF, resulted in a marked decrease in SF1-HP cells and restoration of the CORT circadian rhythm. Our findings suggest that the disappearance of CORT diurnal oscillation is a characteristic of aging individuals and is caused by the secretion of IL1β, one of the SASPs, from senescent cells that accumulate in the zF of the adrenal cortex. These findings provide a novel insight into aging. Age-related hypersecretory GCs could be a potential therapeutic target for aging-related diseases.