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Neutrophils that are overactivated can cause inflammatory diseases. Neutrophils possess various surface receptors, including G-protein-coupled chemoattractant receptors, which assist in recognizing pathogen attacks and the inflammatory environment. Therefore, targeting G-protein-coupled chemoattractant receptors and their downstream molecules is important for preventing abnormal neutrophil activation. This study examines the effects and underlying mechanism of myriscagayanone C, a new compound obtained from the fruit of myristica cagayanensis, on neutrophil respiratory burst induced by fMLP. The immunoblotting assay was conducted to assess the mechanisms by which myriscagayanone C inhibits fMLP-induced respiratory burst by disrupting the translocation of Akt to the cellular membrane. Briefly, myriscagayanone C suppressed the production of superoxide anions induced by fMLP on human neutrophils in a concentration-dependent manner (IC 50 : 4.73 ± 0.68 μM). Myriscagayanone C blocked fMLP-induced Akt translocation to the cell membrane, inhibiting Akt T308 and Akt S473 phosphorylation by PDK1 Y373/376 and mTOR S2481 , respectively. Myriscagayanone C inhibited fMLP-induced p47 phox phosphorylation and translocation. Myriscagayanone C did not inhibit the activity of PI3K, the amount of phosphatidylinositol (3, 4, 5)-trisphosphate, or the translocation of phosphorylated-PDK1 Y373/376 and -mTOR S2481 to the membrane. Myriscagayanone C did not inhibit fMLP-induced PKC, Src, ERK1/2, p38 phosphorylation, and intracellular calcium mobilization. Myriscagayanone C did not inhibit the chemotaxis and CD11b expression induced by fMLP. Myriscagayanone C did not inhibit PMA-induced superoxide anion production and neutrophil extracellular trap formation. According to this data, myriscagayanone C inhibits fMLP-induced neutrophil superoxide anion production by interrupting the translocation of Akt to the plasma membrane, which affects the NADPH oxidase activity by preventing p47 phox phosphorylation and translocation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Introduction: Diesel exhaust particles (DEP) have been proven to aggravate asthma pathogenesis. We previously demonstrated that concurrent exposure to house dust mite (HDM) and DEP in mice increases both eosinophils and neutrophils in bronchoalveolar lavage fluid (BALF) and also results in higher levels of neutrophil-recruiting chemokines and neutrophil extracellular trap (NET) formation compared to sole HDM, sole DEP or saline exposure. We aimed to evaluate whether treatment with anti-IL-5 can alleviate the asthmatic features in this mixed granulocytic asthma model. Moreover, we aimed to unravel whether neutrophils modulate the DEP-aggravated eosinophilic airway inflammation., Material and Methods: Female C57BL6/J mice were intranasally exposed to saline or HDM and DEP for 3 weeks (subacute model). Interference with eosinophils was performed by intraperitoneal administration of anti-IL-5 (TRFK5), which neutralizes IL-5. Interference with neutrophils and neutrophil elastase was performed by intraperitoneal anti-Ly6G and sivelestat administration, respectively. Outcome parameters included eosinophils subsets (homeostatic EOS and inflammatory EOS), proinflammatory cytokines, goblet cell hyperplasia and airway hyperresponsiveness., Results: The administration of anti-IL-5 significantly decreased eosinophilic responses, affecting both inflammatory and homeostatic eosinophil subsets, upon subacute HDM + DEP exposure while BAL neutrophils, NET formation and other asthma features remained present. Neutrophils were significantly reduced after anti-Ly6G administration in BALF, lung and blood without affecting the eosinophilic inflammation upon HDM + DEP exposure. Sivelestat treatment tended to decrease BALF inflammation, including eosinophils, upon HDM + DEP exposure, but did not affect lung inflammation., Conclusion: Inhibition of IL-5 signalling, but not neutrophil interventions, significantly attenuates eosinophilic inflammation in a mouse model of mixed granulocytic asthma, elicited by air pollution exposure., Competing Interests: Declarations. Ethics approval: All in vivo mouse experiments were approved by the Animal Ethical Committee of the Faculty of Medicine and Health Science, Ghent University (ECD19-40, ECD19-22, ECD23-50). Consent for publication: Not applicable. Competing interests: TM holds a Chiesi Chair on the Role of Environmental factors in Asthma development and a GSK chair on eosinophilic airway disease. The other authors declare that they have no competing interests., (© 2025. The Author(s).)

Background: Ulcerative colitis (UC) is a chronic and recurrent digestive tract disease that can lead to significant morbidity and mortality. The pathogenesis of UC is intricately associated with the presence of reactive oxygen species (ROS). Prussian blue (PB), an inorganic nanozyme with potent antioxidant properties, has been extensively applied in the treatment of various inflammatory conditions and tumors. However, despite the explicit antioxidant properties, the underlying molecular mechanism of PB nanozyme in the treatment of UC remains poorly understood. Furthermore, there is a deficiency in antioxidants that possess specific targeting capabilities towards UC lesions. The present study pioneered the fabrication of neutrophil (N)-macrophage (M) hybrid membrane-coated PB (NM-PB) nanozyme for the treatment of UC and investigated its underlying molecular mechanism., Results: We have successfully constructed PB, N-PB, M-PB, and NM-PB nanozymes. In both the colitis cell model and UC mouse model, compared with PB, N-PB, and M-PB nanozymes, NM-PB nanozymes exhibited remarkable targeting capabilities, significantly enhancing the localization and uptake of PB nanozymes at the lesion site. NM-PB nanozymes significantly reduced levels of ROS (•OH, •OOH, and H 2 O 2 ) and decreased the production of proinflammatory cytokines (TNF-α, IL-6, IL-1β). Meanwhile, these nanozymes regulated the expression of intestinal mucosal barrier-related proteins (ZO-1, E-cadherin, and Occludin) and apoptosis-related proteins (Bcl2, Bax). Furthermore, NM-PB nanozymes facilitated the polarization of proinflammatory M1-phenotype macrophage towards an anti-inflammatory M2-phenotype. The mechanistic studies demonstrated that NM-PB nanozymes mitigated the progression of UC by inhibiting the pathway of cytokine-cytokine receptor interaction., Conclusion: The NM-PB nanozymes provide a promising and innovative alternative for the treatment of UC, offering enhanced targeting and efficacy through their unique design and mechanism of action., Competing Interests: Declarations. Ethics approval and informed consent: All procedures involving experimental animals were performed in accordance with the guidelines approved by the Institutional Animal Care and Use Committee of Chongqing Medical University. Publication consent: All authors have read and approved the manuscript. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Background: Dexamethasone has proven life-saving in severe acute respiratory syndrome (SARS) and COVID-19 cases. However, its systemic administration is accompanied by serious side effects. Inhalation delivery of dexamethasone (Dex) faces challenges such as low lung deposition, brief residence in the respiratory tract, and the pulmonary mucus barrier, limiting its clinical use. Neutrophil cell membrane-derived nanovesicles, with their ability to specifically target hyper-activated immune cells and excellent mucus permeability, emerge as a promising carrier for pulmonary inhalation therapy., Methods: We designed a novel UiO66 metal-organic framework nanoparticle loaded with Dex and coated with neutrophil cell membranes (UiO66-Dex@NMP) for targeted therapy of severe pneumonia. This was achieved by loading Dex into UiO66 pores and subsequently coating with neutrophil membranes for functionalization., Results: Drug release experiments revealed UiO66-Dex@NMP to exhibit favorable sustained-release properties. Additionally, UiO66-Dex@NMP demonstrated excellent targeting capabilities both in vitro and in vivo . In a mouse model of lipopolysaccharide (LPS)-induced pneumonia, UiO66-Dex@NMP significantly reduced lung inflammation compared to both the control model and Dex administered via inhalation. Histopathological analysis further confirmed UiO66-Dex@NMP's ability to alleviate lung tissue damage., Conclusions: UiO66-Dex@NMP represents a novel and safe inhaled delivery carrier for Dex, offering valuable insights into the clinical management of respiratory diseases, including severe pneumonia., (© 2025 The Author(s). Published by IMR Press.)

Tumor-associated neutrophils (TANs) play a critical role in the progression and prognosis of triple-negative breast cancer (TNBC), with N2-type TANs known for their pro-tumor characteristics. This study introduces CT-1, a derivative of cryptotanshinone that effectively suppresses TNBC growth while selectively reducing the proportion of N2-type TANs within tumor tissue. Notably, CT-1 induces simultaneous ferroptosis in both N2-type TANs and TNBC cells, a dual mechanism that enhances its therapeutic efficacy. The study identifies ferritin heavy chain 1 (FTH1), a key protein in iron metabolism, as the direct target of CT-1. By targeting FTH1, CT-1 facilitates the interaction between NCOA4 and ferritin, triggering ferritinophagy-mediated ferroptosis. These findings position CT-1 as a promising therapeutic agent, offering a strategy to combat TNBC by inducing ferroptosis in both N2-type TANs and cancer cells. This approach underscores the potential of FTH1 as a therapeutic target for treating TNBC., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Inflammatory bowel disease (IBD), encompassing Crohn's disease and ulcerative colitis, involves chronic inflammation of the gastrointestinal tract. Current immune-modulating therapies are insufficient for 30-50% of patients or cause significant side effects, emphasizing the need for new treatments. Targeting the innate immune system and enhancing drug delivery to inflamed gut regions are promising strategies. Neutrophils play a central role in IBD by releasing reactive oxygen species (ROS) and neutrophil extracellular traps (NETs) -DNA-based structures with cytotoxic proteins-that contribute to mucosal damage and inflammation. Recent studies linking ROS production, DNA repair, and NET formation have identified NETs as potential therapeutic targets, with preclinical models showing positive outcomes from NET inhibition. Innovative oral drug delivery systems designed to target gut inflammation directly-without systemic absorption-could improve treatment precision and reduce side effects. Advanced formulations utilize properties such as particle size, surface modifications, and ROS-triggered release to selectively target the distal ileum and colon. A dual strategy that combines a deeper understanding of IBD pathophysiology to identify inflammation-related therapeutic targets with advanced drug delivery systems may offer significant promise. For instance, pairing NET inhibition with ROS-responsive nanocarriers could enhance treatment efficacy, though further research is needed. This synergistic approach has the potential to greatly improve outcomes for IBD patients.

Human neutrophils are abundant, short-lived leukocytes that turn over at a rate of approximately 1011 cells/day via a constitutive apoptosis program. Certain growth factors, inflammatory mediators and infectious agents can delay apoptosis or induce neutrophils to die by other mechanisms. Nonetheless, a large body of data demonstrates that apoptosis of untreated neutrophils typically ensues within 24 hours of cell isolation and in vitro culture. At the molecular level apoptosis is driven by executioner caspase-3, and during this process cell proinflammatory capacity and host defense functions are downregulated. We undertook the current study to determine the extent to which human neutrophil viability and function could be prolonged by treatment with the non-toxic, irreversible, pan-caspase inhibitor Q-VD-OPh. Our data demonstrate that a single 10 μM dose of this drug was sufficient to markedly prolong cell lifespan. Specifically, we show that apoptosis was prevented for at least 5 days as indicated by analysis of nuclear morphology, DNA fragmentation, and phosphatidylserine externalization together with measurements of procaspase-3 processing and caspase activity. Conversely, mitochondrial depolarization declined despite abundant Myeloid Cell Leukemia 1 (MCL-1). At the same time, glutathione levels were maintained and Q-VD-OPh prevented age-associated increases mitochondrial oxidative stress. Regarding functional capacity, we show that phagocytosis, NADPH oxidase activity, chemotaxis, and degranulation were maintained following Q-VD-OPh treatment, albeit to somewhat different extents. Thus, a single 10 μM dose of Q-VD-OPh can sustain human neutrophil viability and function for at least 5 days., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2025 Khuu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Neutrophils communicate with one another and amplify their destructive power through swarming, a collective process that synchronizes the activities of multiple neutrophils against one target. The sequence of activities contributing to swarming against clusters of fungi has been recently uncovered. However, the molecular signals controlling the neutrophils' activities during the swarming process are just emerging. Here, we report that spleen tyrosine kinase (SYK) inhibitors severely impair neutrophil swarming responses, resulting in the complete loss of fungal restriction. These findings are enabled by a microscale platform to probe the biology of human neutrophils swarming against uniformly sized clusters of growing Candida albicans , a representative opportunistic fungal pathogen. We take advantage of the ability to monitor large arrays of swarms and quantify the effect of multiple chemical inhibitors on different phases of human neutrophil swarming. We show that inhibitors that interfere with PI3Ky signaling disrupt the regulation of the initiation of swarming, while the activation of JNK signaling is essential for the activation of biochemical antifungal functions. Furthermore, we reveal that granulocyte colony-stimulating factors (GCSF and GM-CSF) can partially rescue the antifungal functions of neutrophils exposed to SYK inhibitors. These findings advance our understanding of neutrophil swarming biology in humans and lay the foundation for novel therapeutics that may restore neutrophil function during immunosuppression., Importance: Neutrophils can amplify their destructive power through swarming, a crucial process against large targets that individual neutrophils cannot destroy. However, the molecular mechanisms controlling this process are just emerging. Here, we leveraged microscale tools to probe the biology of swarming against fungi. We used multiple chemical inhibitors and mapped SYK, PI3Ky, and JNK signaling roles during human neutrophil swarming against fungal clusters of Candida albicans . We also found that treating human neutrophils with GCSF and GM-CSF rescues some neutrophil antifungal function during SYK inhibition. These findings advance our understanding of swarming biology in humans while laying the foundation for developing therapeutics that enhance neutrophil function during immunosuppression., Competing Interests: The authors declare no conflict of interest.

Introduction: Acute respiratory distress syndrome (ARDS) is a life-threatening type of acute lung injury (ALI) characterized by elevated mortality rates and long-term effects. To date, no pharmacological treatment has proven effective for ARDS. Mesenchymal stem cell-derived apoptotic vesicles (apoVs) were recently found to have excellent therapeutic potential for inflammatory diseases. In this study, our aim was to investigate the therapeutic effects and underlying mechanisms of apoVs in ALI., Methods: ALI was induced in mice through intratracheal instillation of lipopolysaccharide (LPS). ApoVs were then administered two hours post-induction, and their impacts on platelet activation, neutrophil infiltration, and NETosis were assessed. Additionally, the role of CD73 in mediating these effects was thoroughly investigated., Results: ApoVs inhibit platelet activation, thereby impeding the infiltration of neutrophils into the lung and the initiation of NETosis, ultimately alleviating ALI. Remarkably, apoVs were enriched with CD73, which was critical for apoV-mediated repression of platelet activation and neutrophil NETosis, as well as the therapeutic effects observed in lung injury., Conclusion: This study reveals that apoVs inhibit platelet activity and neutrophil NETosis via CD73, offering an innovative and effective cell-free therapeutic strategy for ALI/ARDS., Competing Interests: The authors declare no potential conflicts of interest in this work., (© 2025 Tan et al.)

Background: This study aimed to clarify whether the neuroprotective effect of LXA4 is associated with the targeting of neutrophil extracellular traps (NETs) in ischemic stroke (IS)., Methods: The MCAO rat model was established to assess cerebral infarction, brain water content and neurological deficits. ELISA was employed to examine the activities of MPO, NE, MMP-9. RT-qPCR and western blot was performed to analyze molecular expressions. A luciferase reporter assay was performed to measure the effect of EGR1 on the METTL3 promoter. The formation of NETs and cell viability were evaluated using immunofluorescence staining and CCK8 assay, respectively., Results: LXA4 decreased cerebral infarction and brain water content, improved neurological deficits, and reduced the release of NETs-associated indicators (MPO, NE) in MCAO rats. LXA4 reduced NETs formation, MPO and NE levels in vitro. In addition, LXA4 reduced Fe 2 + levels while increasing GPX4, SLC7A11 protein expressions, as well as enhancing cell viability in vitro, suggesting the inhibitory effect of LXA4 on ferroptosis. Notably, METTL3 overexpression produced the opposite effects. Furthermore, the effects of METTL3 overexpression on NETs formation and ferroptosis were partially reversed by LXA4 treatment. The inhibition of METTL3 by LXA4 was found to be dependent on FPR2. In vivo experiments verified that LXA4 inhibited NETs formation through inhibition of METTL3 to alleviate brain injury., Conclusion: This study demonstrates that LXA4 suppresses NETs formation through the FPR2-dependent regulation of METTL3, thereby alleviating brain injury in IS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

A mounting number of studies have been documenting strong pro-inflammatory and pro-fibrotic effects of carbon nanotube (CNT). However, the molecular mechanisms of single-walled CNT (SWCNT)-provoked lung injury remain to be elucidated. Here, we established a mice model of SWCNT-induced lung injury by intratracheal instillation and found that C5a-C5a receptor-1 (C5aR1) signaling was significantly activated along with abundant neutrophils recruitment in lungs at early phase post SWCNT administration, which were positively correlated with early lung inflammation and late pulmonary fibrosis. C5a-C5aR1 signaling activation and neutrophils recruitment were subsequently decreased in a time-dependent manner. Furthermore, inhibition of C5a-C5aR1 axis with C5aR1 antagonist PMX205 treatment not only dramatically reduced neutrophils recruitment and inflammatory cytokines secretion at early phase, but also effectively alleviated early lung inflammation and late pulmonary fibrosis induced by SWCNT exposure. In conclusion, our study provides novel insights into the underlying biological mechanism that C5a-C5aR1 axis regulates neutrophils recruitment-mediated lung injury induced by SWCNT, may help to develop therapeutic strategies for SWCNT-provoked lung injury., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Chronic obstructive pulmonary disease (COPD) imposes a significant global health and socioeconomic burden. Exacerbations of COPD (ECOPD), characterized by heightened airway inflammation and mucus hypersecretion, adversely affect patient health and accelerate disease progression. Qingke Pingchuan (QKPC) granules, a formulation from Traditional Chinese Medicine initially prescribed for acute bronchitis, have shown unexplored potential in ECOPD management, with mechanisms of action yet to be clarified., Purpose: This study investigates the therapeutic effects of QKPC in a mouse model of ECOPD, focusing on underlying molecular mechanisms., Methods: COPD was induced in mice through chronic cigarette smoke (CS) exposure, followed by intratracheal administration of Pseudomonas aeruginosa lipopolysaccharide (LPS) to trigger exacerbation, after which mice were treated with QKPC granules. Major compounds in QKPC were identified via UHPLC-QE-MS, and high-throughput RNA sequencing of lung tissue samples identified differentially expressed genes. Transcriptomic data were integrated with network pharmacology analysis to pinpoint potential pathways, bioactive compounds, and target genes through which QKPC might attenuate ECOPD. Molecular docking, protein-small molecule binding assays, and in vitro analyses further validated interactions between key compounds and target genes, shedding light on plausible signaling pathways., Results: QKPC treatment led to significant reductions in airway leukocyte infiltration and goblet cell metaplasia in CS- and LPS-exposed mice, accompanied by decreased levels of inflammatory cytokines (IL-6, IL-1β, CXCL1, and TNF-α) and mucin MUC5AC in bronchoalveolar lavage fluid. The integrative transcriptomic and network pharmacology analysis identified the neutrophil extracellular trap (NET) formation pathway as a key mechanism underlying QKPC's protective effect against ECOPD. In vitro assays demonstrated that epigallocatechin-3-gallate (EGCG) and quercetin, two important bioactive compounds in QKPC, significantly inhibited NETosis induced by cigarette smoke extract (CSE) plus LPS in human neutrophils. The two compounds were found to interact directly with the reactive oxidative species (ROS)-generating enzyme NOX2 and its regulatory subunit p47phox. Subsequent in vitro studies further confirmed EGCG and quercetin's capacity to reduce ROS production and downregulate NOX2 and p47phox protein levels in neutrophils stimulated with CSE and LPS. Additionally, in vivo studies confirmed QKPC's efficacy in reducing NET formation, oxidative stress, and NOX2/p47phox protein expression in the lung tissue of ECOPD mice., Conclusion: These findings suggest that QKPC granules alleviate airway inflammation in ECOPD, potentially through inhibition of pulmonary NET formation via the NOX2/p47phox-ROS pathway, underscoring their potential therapeutic application for ECOPD management in clinical settings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: Rheumatoid arthritis (RA) is a common autoimmune disease with a high disability rate. Accumulating studies suggest that neutrophil extracellular traps (NETs) play a crucial role in the pathogenesis of RA and targeting NETs has emerged as a potential therapeutic strategy for RA. As a traditional Chinese medicine, Guizhi-Shaoyao-Zhimu Decoction (GSZD) has exhibited good efficacy in the treatment of rheumatoid arthritis (RA), while the underly mechanism especially the possibility that GSZD alter NETs formation to relieve RA remains unknown., Purpose: Our study aimed to investigate relationship between GSZD and NETs in RA treatment and revealed underlying mechanism., Methods: We constructed collagen-induced arthritis (CIA) model and treated CIA mice with GZSY to validate therapeutic effects of GSZD and examine whether GZSD could inhibit NETs formation in RA. And 16S rRNA sequencing and Fecal microbiota transplantation (FMT) experiment were performed to determine whether GSZD could reduce NETs formation to alleviate RA in gut microbiota-associated manner and identify crucial bacterium in response to GSZD administration. CIA mice treated with effective bacteria and its outer membrane vesicles (OMVs) with oral administration to investigate protective effect against RA and NETs regulative efficiency. We utilized small interfering RNA in vivo and vitro to silence gene mediating effect of GZSD-gut microbiota-NETs., Results: GSZD could inhibit NETs formation and relive arthritis in CIA mice. Additionally, GSZD alter gut microbiota composition and significantly increase intestinal Parabacteroides goldsteinii (P.goldsteinii) abundance. Mechanistically, P.goldsteinii enriched by GSZD secreted outer membrane vesicles (OMVs) to translocate into joints and activate Cav-1-Nrf2 axis, leading to reduced NETs formation and alleviate arthritis. In clinical, the abundance of P.goldsteinii exhibited negative correlation with NETs indexes and RA disease activities., Conclusion: Our findings suggest that GSZD inhibits NETs formation to relieve RA in P.goldsteinii-Cav-1-Nrf2 associated manner, which could provide new sight of the prevention and treatment of RA., Competing Interests: Declaration of competing interest The authors announce that there is no conflict of interest regarding the publication of this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Dapsone is a sulfone used in treating inflammatory skin conditions. Despite its widespread dermatological use, the pharmacological actions of dapsone remain poorly understood. Here, we examined how different aspects of neutrophil functions are affected by dapsone. Peripheral blood neutrophils from healthy donors were stimulated with phorbol-12-myristate-13-acetate (PMA), N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP), or calcium ionophore (CaI) or primed with cytokines prior to stimulation, in the presence of different concentrations of dapsone (from 10 to 50 µg/mL), followed by analyses of their survival, phenotype, and functional properties. We found that dapsone at the concentration of 50 μg/mL induced a significant neutrophil apoptotic rate during 6 h and 18 h, while other concentrations were well tolerated compared to control non-treated cells. However, dapsone significantly decreased the induced oxidative burst of neutrophils at all non-cytotoxic concentrations. Additionally, dapsone showed a dose-dependent suppression of NETosis in activated neutrophils. The production of IL-8 by dapsone-treated neutrophils was decreased under both stimulated (fMLP) and primed (TNF-α/fMLP) conditions. Moreover, dapsone inhibited the expression of CD11b/CD18, CD66, and CD89 and reversed or significantly mitigated the downregulation of CD16, CD32, CD181, CD88, and CD62L on neutrophils after priming and fMLP stimulation. In conclusion, our results indicate the complexity of dapsone actions on neutrophil functions, extending previous knowledge on the suppression of oxidative burst and IL-8 production upon neutrophils' activation. Suppressed NETosis and modulation of marker expression associated with different neutrophil functions under inflammatory conditions are new findings, not recognized previously.

Cold atmospheric plasma (CAP) has antimicrobial properties and is also known to stimulate the immune system. These properties could be useful for the development of a novel therapeutic or preventive strategy against respiratory infections in the upper respiratory tract (URT) such as ventilator-associated pneumonia (VAP) without inducing an immune overreaction. This study investigated the cellular responses of polymorphonuclear neutrophils (PMNs) after exposure to CAP in a three-dimensional (3D) model of the URT. In vitro experiments were conducted using PMNs isolated from human blood to assess cell migration, intracellular production of reactive oxygen species (ROS), NETosis, surface marker expression (CD11b, CD62L, and CD66b), and cell death with live cell imaging and flow cytometry. CAP was applied for 5 min using two distinct modalities: pressurized air plasma with a plasma intensive care (PIC) device and nebulized air plasma (NP) with a new humidity resistent surface microdischarge (SMD) plasma source, both developed by Terraplasma Medical GmbH. There were no significant signs of cell damage or overstimulation with either device under the conditions tested. However, the NP device caused milder effects on PMN functionality compared to the PIC device, but also demonstrated reduced antibacterial efficacy and reactive oxygen/nitrogen species (RONS) production, as analyzed with colorimetric/fluorimetric assay kits. These findings highlight a trade-off between the two CAP modalities, each with distinct advantages and limitations. Further studies are necessary to investigate these effects in the clinical setting and evaluate the long-term safety and efficacy of CAP treatment in the URT.

Neutrophil extracellular traps (NETs) formation is a key process in inflammatory diseases like gout, but the underlying molecular mechanisms remain incompletely understood. This study aimed to establish a model to examine the formation of NETs induced by monosodium urate (MSU) and phorbol 12-myristate 13-acetate (PMA) and to elucidate their molecular pathways. Laser confocal microscopy was used to visualize NET formation, while flow cytometry was employed to detect reactive oxygen species (ROS) production. The microstructure of neutrophils was observed by transmission electron microscopy, and the expression of key proteins was determined by Western blotting. Additionally, the effect of various inhibitors targeting the MAPK signaling pathway on NET formation was evaluated. They include the Ras inhibitor Salirasib, Raf inhibitor Vemurafenib, ERK inhibitor PD98059, and p38 MAPK inhibitor SB203580, as well as NADPH oxidase inhibitor DPI and neutrophil elastase inhibitor Alvelestat. The results showed that MSU and PMA triggered significant NET formation, which was accompanied by increased ROS levels, lactate dehydrogenase release, dsDNA, and IL-8. Notably, selective MAPK pathway inhibitors and DPI and Alvelestat, except for SB203580, effectively down-regulated these indicators. These data indicated that the activation of a signaling pathway involving Ras-Raf-ERK, which is dependent on ROS, is crucial for the induction of NET formation by MSU and PMA. Given the involvement of NETs in multiple pathologies, our findings could potentially serve as molecular targets for the intervention and treatment of crystal-related diseases, especially for gout.

Chronic inflammation is a common characteristic of all kinds of diseases, including autoimmune diseases, metabolic diseases, and tumors. It is distinguished by the presence of low concentrations of inflammatory factors stimulating the body for an extended period, resulting in a persistent state of infection. This condition is manifested by the aggregation and infiltration of mononuclear cells, lymphocytes, and other immune cells, leading to tissue hyperplasia and lesions. Although various anti-inflammatory medications, including glucocorticoids and non-steroidal anti-inflammatory drugs (NSAIDs), have shown strong therapeutic effects, they lack specificity and targeting ability, and require high dosages, which can lead to severe adverse reactions. Nanoparticle drug delivery mechanisms possess the capacity to minimize the effect on healthy cells or tissues due to their targeting capabilities and sustained drug release properties. However, most nanosystems can only target the inflammatory sites rather than specific types of immune cells, leaving room for further improvement in the therapeutic effects of nanomaterials. This article reviews the current research progress on the role of diverse immune cells in inflammation, focusing on the functions of neutrophils and macrophages during inflammation. It provides an overview of the domestic and international applications of nanomaterials in targeted therapy for inflammation, aiming to establish a conceptual foundation for the utilization of nanomaterials targeting immune cells in the treatment of chronic inflammation and offer new perspectives for the avoidance and management of inflammation., Competing Interests: All authors declared no conflicts of interest in this work., (© 2024 Ci et al.)

Background: Proton pump inhibitors (PPIs) are one of the most used drugs worldwide. While generally considered safe, the usage of PPIs is associated with several adverse outcomes including acute infectious diseases. PPIs influence macrophage and neutrophil function although a systematic review has never been undertaken. The purpose of this systematic review was to determine the potential mechanisms of how PPI-induced inhibition of macrophage and neutrophil function may increase infection risk in susceptible hosts., Methods: A database search using Scopus and PubMed was performed to identify studies that investigated the effects of PPIs on neutrophils or macrophage function., Results: The final screening yielded 21 English-language research articles that focused on the impacts of PPIs on the function of macrophages and neutrophils. PPI mechanistic effects included cytotoxic effects on polymorphonuclear neutrophils, inhibition of reactive oxygen species (ROS) and reactive nitrogen species, phagocytosis and phagosomal degradation, inhibition of chemotaxis and migration, altering Toll-like receptor signaling and p38 protein phosphorylation in immune cells, and altering neutrophil and macrophage gene expression., Discussion: The impact of PPIs on MΦs and neutrophils regarding their role in the immune response to bacterial pathogens was summarized. PPI effects on macrophages and neutrophils occurred due to the therapeutic mechanism of PPIs, the protonation of sulfhydryl groups and the subsequent formation of a disulfide bond, and other pleiotropic manners. Given the common use of PPIs, these results highlight the necessity to optimize PPI use and stewardship to curtail unnecessary drug use., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Fowler, Eubank and Garey.)

Background: Mixed granulocytic asthma (MGA) is usually associated with poor response to corticosteroid therapy and a high risk of severe asthma. Cathepsin S (CTSS) has been found to play an important role in various inflammatory diseases. This study was aimed to investigate the role of CTSS in MGA., Methods: Induced sputum was obtained from healthy subjects and asthma patients. Two murine models of MGA were established using either TDI (toluene diisocyanate) alone or OVA emulsified in CFA. LY3000328, a specific antagonist of CTSS, was therapeutically given to BALB/c mice after airway challenge with TDI or OVA. The effects of recombinant CTSS was tested in vivo, and Akt inhibition was used to explore a possible mechanism for CTSS-induced airway inflammation., Results: MGA patients have a significant higher sputum CTSS level than the health and subjects with other inflammatory phenotypes, which was positively correlated with sputum level of soluble E-cadherin (sE-cadherin), sputum neutrophils, FeNO, FEF25-75% and glucocorticoid dosage. Allergen exposure markedly increased CTSS level and pharmacological antagonism of CTSS with LY3000328 decreased airway hyperresponsiveness, airway neutrophil accumulation, as well as the release of IL-17 and sE-cadherin in murine models of MGA, yet had no effects on eosinophilic inflammation nor type 2 inflammatory cytokines (IL-4 and IL-5). In addition, intratracheal instillation of recombinant CTSS leads to neutrophil recruitment and overproduction of sE-cadherin in the lung tissues, which could be attenuated by inhibition of Akt signaling., Conclusion: Our data suggested that CTSS contributes to airway neutrophilic inflammation in MGA through an Akt-dependent pathway., Competing Interests: Declarations. Ethics approval and consent to participate: All subjects signed informed consent forms approved by the Ethics Committee of our institution [Medical Ethics Year 2022 (No. 55)]. All animal experiments described here complied with the guidelines of the Committee of Guangzhou Medical University on the use and care of animals and were approved by the Animal Subjects Committee of Guangzhou Medical University. Consent for publication: Not Applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Neutrophils and neutrophil extracellular traps (NETs) contribute to thrombosis and hyperinflammation in myeloproliferative neoplasms (MPN). High-density neutrophils (HDNs) and low-density neutrophils (LDNs) have recently been characterized as distinct neutrophil sub-populations with distinct morphological and functional properties. We aim to study the kinetics of NET formation and inhibition with interferon-α (IFNα) in neutrophils derived from patients with MPN as compared to matched healthy controls. Ex vivo NET formation was assessed by neutrophil-elastase activity, neutrophil-associated nucleosomes, myeloperoxidase (MPO), and citrullinated histone H3 content. IFNα significantly inhibited NET formation in neutrophils derived from MPN patients. Neutrophil sub-population analysis demonstrated that HDNs drive the increase in NET formation as compared to LDNs in patients and in healthy controls and are effectively inhibited by IFNα, an effect that is lost in LDNs. In conclusion, we demonstrate that in MPN, HDNs drive excess NET formation and are more sensitive to IFNα inhibition. These observations uncover unique neutrophil sub-population biology and dynamics in MPN.

Anti-disialoganglioside (GD2) antibody therapy has provided clinical benefit to patients with neuroblastoma however efficacy is likely impaired by the immunosuppressive tumor microenvironment. We have previously defined a link between intratumoral copper levels and immune evasion. Here, we report that adjuvant copper chelation potentiates anti-GD2 antibody therapy to confer durable tumor control in immunocompetent models of neuroblastoma. Mechanistic studies reveal copper chelation creates an immune-primed tumor microenvironment through enhanced infiltration and activity of Fc-receptor-bearing cells, specifically neutrophils which are emerging as key effectors of antibody therapy. Moreover, we report copper sequestration by neuroblastoma attenuates neutrophil function which can be successfully reversed using copper chelation to increase pro-inflammatory effector functions. Importantly, we repurpose the clinically approved copper chelating agent Cuprior as a non-toxic, efficacious immunomodulatory strategy. Collectively, our findings provide evidence for the clinical testing of Cuprior as an adjuvant to enhance the activity of anti-GD2 antibody therapy and improve outcomes for patients with neuroblastoma., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Previous research has demonstrated that a combined magnetic field (CMF) plays a critical role in modifying the properties of aqueous solutions, leading to an increase in the luminol-enhanced chemiluminescence of neutrophils. Using this model, the distant interaction between aqueous solutions was demonstrated, and the role of a CMF in the regulation of this phenomenon was established. In the current study, highly diluted (HD) phorbol myristate acetate (PMA) solution (the donor) was incubated with aqueous ethanol (the acceptor), both in a CMF-generating device and under geomagnetic field (GMF), for 0, 20, and 60 min. After a 60 min incubation at a 0 cm distance with HD PMA under both GMF and CMF, acceptor samples added to neutrophils increased neutrophil chemiluminescence by approximately sevenfold. The ability of HD PMA, which had been incubated with an acceptor, to activate ROS production diminished within 60 min of observation. However, the HD PMA sample remained an effective donor for up to 6 days after preparation. At a 10 cm distance between the donor and acceptor, the activation of the acceptor did not occur. These findings provide new insights into the phenomenon of distant interaction of solutions, whose mechanisms are suggested to be related to the quantum electrodynamics of water molecular dynamic structures.

Purpose: Given the increased use of polyethylene glycol (PEG) in refining the therapeutic activity of medicines, our research focuses on explaining the potential mechanism of immune reactions associated with this polymer. We aim to investigate the interaction of different types of PEG with mouse and human immune cells, thereby contributing to understanding PEG interactions with the immune system and verifying the proinflammatory activity of the tested polymers., Patients and Methods: Mouse macrophage and neutrophil cell lines, human peripheral blood mononuclear cells, and polymorphonuclear cells isolated from healthy donors were exposed to various PEGs. ROS, NO, and cytokine production were analyzed using fluorescence intensity, absorbance, or cytometric measurements. Toll-like receptor (TLR) signaling was verified using HEK-blue-reporter cell lines. Finally, neutrophil trap formation was studied using immunofluorescence labeling, and calcium imaging was performed using a Ca 2+ -sensitive indicator and fluorescence microscope., Results: Our findings show that specific PEG and mPEG are not toxic to tested mouse and human cells. However, they exert proinflammatory activity against human immune cells, as evidenced by the increased secretion of proinflammatory cytokines, such as IFN-a2, IFN-γ, TNF-α, MCP-1, IL-8, IL-17A, and IL-23. This phenomenon is independent of PEG signaling via TLR. Additionally, mPEG10 induced the formation of neutrophil extracellular traps and intracellular calcium signaling., Conclusion: Our finding suggests that some PEG types have proinflammatory activity against human immune cells, manifesting in the upregulated production of cytokines and neutrophils trap releasing., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Hinz et al.)

Background: Exposure to standard petrodiesel exhaust is linked to adverse health effects. Moreover, there is a mounting request to replace fossil-based fuels with renewable and sustainable alternatives and, therefore, rapeseed methyl ester (RME) and other biofuels have been introduced. However, recent toxicological research has indicated that biodiesel exhaust may also induce adverse health-related events., Aim: To determine whether exposure to 100% RME biodiesel (BD100) exhaust would cause an acute airway neutrophilic recruitment in humans., Methods: Fourteen healthy subjects underwent exposure to diluted BD100 exhaust and filtered air for 1-h, in a blinded, random fashion. Bronchoscopy with endobronchial mucosal biopsies, bronchial wash (BW) and bronchoalveolar lavage (BAL) was performed six hours after exposure. Differential cell counts and inflammatory markers were determined in the supernatant and biopsies were stained immunohistochemically., Results: Compared with filtered air, BD100 exhaust exposure increased bronchial mucosal endothelial P-selectin adhesion molecule expression, as well as neutrophil, mast cell and CD68 + macrophage numbers. An increased influx of neutrophils and machrophages was also seen in BW., Conclusion: Exposure to biodiesel exhaust was associated with an acute airway inflammation that appeared similar to preceding petrodiesel exposure studies. The present findings, together with the recently reported adverse cardiovascular effects after similar biodiesel exposure, indicate that biodiesel is not free of toxicity and may affect human health., Competing Interests: Declarations. Ethics approval and consent to participate: The study was performed according to the Helsinki declaration and approved at the local ethics committee at Umeå university. All participants gave their written informed consent to participate. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: BG is a novel bioactive peptide derived from bitter gourd ( Momordica charantia ), known for its anti-inflammatory and immunomodulatory properties. In the present study, our objective is to investigate the functional roles and mechanisms of BG in the context of rheumatoid arthritis (RA). Methods: A rat model of adjuvant-induced arthritis (AIA) was established by administering complete Freund's adjuvant (CFA). The viability of BG-mediated AIA was evaluated by assessing changes in rat body weight, joint swelling, ankle joint pathology, inflammation, necroptosis, the formation of neutrophil extracellular traps (NETs), and gut microbiota. Results: The results of the study showed that peptide BG was effective in improving weight loss, joint swelling, serum IgM-rheumatoid factor (IgM-RF) level, and pathological injury of ankle joint in rats with AIA. BG administration resulted in a decrease in erythrocyte sedimentation rate, serum C-reactive protein (CRP), and inflammatory factor (interferon- γ (IFN-γ), interleukin-1 β (IL-1 β ), and tumor necrosis factor- α (TNF- α )) in AIA rats. Additionally, the administration of CFA resulted in an increase in the protein levels of myeloperoxidase (MPO), neutrophil elastase (NE), citrullinated histone H3 (CitH3), peptidyl arginine deiminase 4 (PAD4), p-mixed lineage kinase domain-like (p-MLKL), and cleaved caspase 8. However, this increase was found to be inhibited by BG treatment. Furthermore, it has been found that peptide BG possesses the capacity to regulate the species composition structure of the intestinal microbiota, thereby, facilitating the reestablishment of microbial diversity and equilibrium. Conclusion: Peptide BG has demonstrated efficacy in ameliorating AIA through its regulation of the necroptosis/NETs/inflammation axis and the gut microbiota. This finding underscores the potential of BG as a promising therapeutic intervention for RA., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Wenyan Han et al.)

Background: It has been found that patients with schizophrenia are often accompanied by concomitant changes in inflammation levels during acute exacerbations, and some studies have suggested that the inflammatory indices neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and monocyte/lymphocyte ratio (MLR) may be biomarkers of acute exacerbations in schizophrenia; however, few studies have simultaneously explored the differences in these inflammatory indices in the drug-free patients with schizophrenia in acute phase (DSA), medicated patients with schizophrenia in acute phase (MSA), medicated patients with schizophrenia in remission period (MSR), as well as the effects of different antipsychotic medications on inflammatory indices., Method: A total of 651 subjects including 184 healthy controls (HC), 167 DSA, 119 MSA, and 181 MSR were included in this study. Demographic and disease information was collected from each individual and venous blood was collected to detect immune cells and calculate the inflammatory indices NLR, PLR, and MLR, and statistical methods such as analysis of variance (ANOVA) and multiple comparisons were utilized to explore the alteration of these inflammatory indices under the influence of different antipsychotics and in HC, DSA, MSA, and MSR., Results: NLR was significantly higher in DSA and MSA than in HC after adjusting the confounders of sex, age, smoking, years of education, marital status, BMI, diabetes, and hypertension. PLR and MLR were not significantly different in patients with schizophrenia and in HC, and were not significantly different in patients with schizophrenia in any group. In MSA and MSR, NLR was positively correlated with disease duration and negatively correlated with the use of mood stabilizers., Conclusions: NLR was significantly increased in acute phase of schizophrenia, regardless of use of antipsychotic drugs, but not significantly increased in stable phase, which might be a promising biomarker for acute phase of schizophrenia., Competing Interests: Declarations. Ethics approval and consent to participate: Considering that the study would not expose the privacy of any subjects and that some subjects were difficult to contact, we applied for a waiver of informed consent to the Institutional Review Board. The Medical Ethics Committee of Zhejiang Xiaoshan Hospital waived the need for consent to participate and approved this study on January 25, 2024 (Approval NO. 2024–004). Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Targeting neutrophil function has gained attention as a propitious therapeutic strategy for diverse inflammatory diseases. Accordingly, a series of enone-based derivatives were developed to inhibit neutrophil-mediated inflammation, showing promise for treating inflammatory diseases. These compounds fall into two clusters with distinct effects: one inhibits neutrophilic superoxide (SO) anion production and elastase release triggered by N-formyl-Met-Leu-Phe (fMLF), with compound 6a being most effective (IC 50 values of 1.23 and 1.37 μM, respectively), affecting c-Jun N-terminal kinase (JNK) and Akt phosphorylation. The second cluster suppresses formation of SO anion without affecting elastase levels, surpassed by compound 26a (IC 50 of 1.56 μM), which attenuates various mitogen-activated protein kinases (MAPKs) with minimal Akt impact. Notably, none of the tested compounds showed cytotoxicity in human neutrophils, underscoring their potential as therapeutic agents against inflammatory diseases.

Context: Virtually all parts of Salvadora persica L. (Salvadoraceae) are used in traditional medicine. The twigs and leaves are used for oral health, but leaves are far less investigated., Objective: This study assesses the oral health-promoting potential of S. persica leaves with emphasis on anti-inflammatory and antiproliferative effects and provides an in depth-characterization of their metabolite profile., Materials and Methods: Hot-water and methanolic S. persica leaf extracts (1, 10, and 100 µg/mL) and their major constituents (5, 10, and 50 µM), were subjected to cellular assays on IL-8 and TNFα release in LPS-stimulated human neutrophils, NO-release in LPS/IFNγ stimulated mouse macrophages, and proliferation of HNO97 human tongue carcinoma cells. Metabolite profiling was performed by UHPLC-HRMS analysis. Major constituents were isolated and structurally elucidated., Results and Discussion: Both extracts showed pronounced anti-inflammatory activity in LPS-stimulated neutrophils. Major identified compound classes were flavonoid glycosides, the glucosinolate glucotropaeolin, phenyl- and benzylglycoside sulfates, and megastigmane glycosylsulfates, the latter ones identified for the first time in S. persica . Glucotropaeolin strongly inhibited the release of IL-8 and TNF-α (13.3 ± 2.0 and 22.7 ± 2.6% of the release of stimulated control cells at 50 µM), while some flavonoids and 3-(3'- O -sulfo-β-d-glucopyranosyloxy)-7,8-dihydro-β-ionone, a newly isolated megastigmane glycosylsulfate, were moderately active. Benzylisothiocyanate, which is likely formed from glucotropaeolin during traditional application of S. persica, showed considerable antiproliferative activity (IC 50 in HNO97 cells: 10.19 ± 0.72 µM) besides strongly inhibiting IL-8 and TNFα release., Conclusions: Glucotropaeolin and benzylisothiocyanate are likely implicated in the oral health-promoting effects of S. persica leaves. The chemistry and pharmacology of the newly identified megastigmane glycosylsulfates should be further evaluated.

Background: Myocardial infarction (MI), representing the most severe manifestation of coronary artery disease (CAD), stands as a primary concern in the prevention and management of cardiovascular diseases. Clinical evidence demonstrates that Qingxin Jieyu Granule (QXJYG) is efficacious in treatment of MI patients. However, the mechanisms underlying its therapeutic effects remain to be elucidated., Purpose: This study aimed to evaluate the effects of QXJYG on MI and investigate its underlying mechanisms., Materials and Methods: The MI model in rats was developed through ligating the left anterior descending (LAD) artery. The effect of QXJYG on cardiac function impairment in MI rats was assessed by echocardiography, while the improvement of cardiomyocyte morphology and myocardial fibrosis after treatment with QXJYG was evaluated through hematoxylin-eosin (H&E) staining and Masson staining. The chemical constituents of QXJYG in blood were identified by using the UPLC-Q-TOF/MS technique. Furthermore, the molecular mechanism underlying the QXJYG therapeutic effect in MI was postulated based on the disease gene-drug target network analysis. Other technical methods such as ELISA, immunohistochemical staining, Western Blot analysis and application of pharmacological inhibitors were employed to verify the effectiveness of QXJYG in treating MI and explore its potential molecular targets., Results: The cardiac function in experimental rats post-MI was significantly impaired, as evidenced by an enlarged infarction area, disordered arrangement of cardiomyocytes, and aggravated myocardial fibrosis. QXJYG treatment significantly enhanced the cardiac function and reduced the pathological damage of the cardiac tissue in MI rats. Through the network pharmacology analysis, we identified that FPR2 might be a potential target of QXJYG in its cardiac protection role. QXJYG markedly downregulated the level of neutrophil extracellular traps (NETs) in MI rats, specifically manifested as a significant reduction in the Histone-DNA level and expression of myeloperoxidase (MPO) and citrullinated histone H3 (CitH3) proteins. Furthermore, QXJYG upregulated the levels of ANXA1 and FPR2 proteins in MI rats. The level of FPR2 was markedly reduced in MI rats upon administration of WRW4, a specific inhibitor of FPR2, which was associated with exacerbated MI injury and an elevated level of NETs. When WRW4 was co-administered with QXJYG, the cardioprotective effects of QXJYG on MI were significantly diminished. However, the addition of DNase I did not result in significant changes of the outcomes in MI rats after QXJYG intervention., Conclusion: QXJYG treatment alleviates cardiac tissue injury in MI rats by inhibiting NETs through activating the ANXA1/FPR2 axis. The findings extend our understanding of the therapeutic effectiveness of QXJYG and offer a scientific foundation for the clinical utilization of QXJYG., Competing Interests: Declaration of competing interest The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Background: Neutrophilic asthma (NA) is one of the most important phenotypes of non-Th2 asthma and is often insensitive to glucocorticoid therapy, making current treatment difficult. Shemazhichuan Liquid (SMZCL), a Chinese medicine compound preparation, has unique advantages in the treatment of asthma. However, the underlying mechanisms of SMZCL in treating NA are not fully understood., Purpose: The efficacy and underlying mechanisms of SMZCL on NA were investigated by TMT-labeled quantitative proteomics analysis and in vivo and in vitro experiments., Methods: NA mouse model was constructed by OVA/CFA sensitization followed by a 10-day challenge with 5 % OVA. Lung histopathology, leukocyte counts and cell sorting counts, inflammatory cytokines levels, as well as expression of autophagy markers were then assessed. The specific pathways and proteins of SMZCL for treating NA were further illustrated through TMT-based quantitative proteomics. In addition, RAW264.7 cells were induced by LPS to further explore the mechanism of the main active ingredient of SMZCL on autophagy pathway., Results: In vivo, SMZCL contributed to attenuating airway inflammation and collagen disposition, markedly reduced the number of leukocytes, especially neutrophils in bronchoalveolar lavage fluid (BALF), as well as decreased IgE and inflammatory cytokine levels (TNF-α, IL-1β, IL-6 and IL-8) in BALF and serum. Besides, SMZCL elevated the levels of LC3 and ATG5 while inhibiting the expression of p62 and mTOR. Mzb1 and Rab3ip were identified as the critical overlapping DEPs whose expression was inhibited by SMZCL and rapamycin. KEGG enrichment analysis showed that necroptosis process was a key pathway for SMZCL to treat NA airway inflammation. IHC and WB results confirmed that SMZCL and rapamycin inhibited the phosphorylation of RIPK1, PIPK3 and MLKL. In vitro, ATG5 and LC3 proteins were obviously increased while p-mTOR expression was inhibited after amygdalin treatment., Conclusion: SMZCL attenuated airway inflammation in NA mainly through inhibition of the mTOR pathway, along with inhibition of the necroptosis pathway regulated by the RIPK1/RIPK3/MLKL axis and inhibition of Mzb1 and Rab3ip expression., Competing Interests: Declaration of competing interest The authors confirm that they do not have any conflicts of interest to declare., (Copyright © 2024. Published by Elsevier GmbH.)

The recent global resurgence of severe infections caused by the Group A streptococcus (GAS) pathogen, Streptococcus pyogenes , has focused attention on this microbial pathogen, which produces an array of virulence factors, such as the pore-forming toxin, streptolysin O (SOT). Importantly, the interactions of SOT with human neutrophils (PMN), are not well understood. The current study was designed to investigate the effects of pretreatment of isolated human PMN with purified SOT on several pro-inflammatory activities, including generation of reactive oxygen species (ROS), degranulation (elastase release), influx of extracellular calcium (Ca 2+ ) and release of extracellular DNA (NETosis), using chemiluminescence, spectrophotometric and fluorimetric procedures, respectively. Exposure of PMN to SOT alone caused modest production of ROS and elastase release, while pretreatment with the toxin caused significant augmentation of chemoattractant (fMLP)-activated ROS generation and release of elastase by activated PMN. These effects of treatment of PMN with SOT were associated with both a marked and sustained elevation of cytosolic Ca 2+ concentrations and significant increases in the concentrations of extracellular DNA, indicative of NETosis. The current study has identified a potential role for SOT in augmenting the Ca 2+ -dependent pro-inflammatory interactions of PMN, which, if operative in a clinical setting, may contribute to hyper-activation of PMN and GAS-mediated tissue injury.

Despite significant advances in the diagnosis and treatment of colorectal cancer (CRC), the prognosis for late-stage patients remains poor, highlighting the urgent need for new preventive and therapeutic strategies. Recent studies have focused on the ketogenic diet (KD) and its metabolite, β-hydroxybutyrate (BHB), for their tumor-suppressive effects and modulation of inflammatory responses. Using the azoxymethane (AOM) / dextran sulfate sodium (DSS)-induced mouse CRC model, we found that the ketogenic diet and BHB inhibit pro-tumor N2-type tumor-associated neutrophils (TANs) while promoting the polarization of TANs towards the anti-tumor N1 type. This shift in TANs polarization affects tumor growth and metastasis. The underlying mechanism involves BHB acting on the intracellular receptor histone deacetylases 3 (HDAC3), which modulates the activation of the AMOT-YAP/TAZ axis, leading to the inhibition of pro-carcinogenic factor transcription and release. Moreover, clinical cohort data corroborate these findings, showing that CRC patients with elevated BHB levels have significantly lower rates of lymph node involvement, which is associated with a higher infiltration ratio of anti-carcinogenic N1-type TANs in the tumor microenvironment (TME). These results suggest that BHB levels could serve as a prognostic biomarker for CRC. In conclusion, our findings indicate that BHB derived from KD regulates TANs polarization in CRC via the HDAC3-AMOT-YAP/TAZ axis, effectively inhibiting tumor growth and metastasis. These insights establish a novel theoretical basis for employing the KD in the treatment of CRC and for developing cancer adjuvant immunotherapy strategy based on the polarization of neutrophils., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Febrile neutropenia is one of the most serious complications in patients with hematological malignancies and chemotherapy. Channa striata is a freshwater fish belonging to the family Channidae. This study aims to determine whether the administration of channa striata extract can increase neutrophil count, neutrophil function and prevent incidence of febrile neutropenia in acute myeloid leukemia (AML) patients receiving chemotherapy., Method: A randomized, single-blind, controlled study compared a standard nutrition from hospital with a channa striata extract-supplemented per oral containing 6 grams of channa striata extract in patients with acute myeloid leukemia undergoing intensive chemotherapy. To analyze the effects of channa striata extract on function of neutrophil, Interleukin (IL)-6 and nitric oxide (NO) levels which are the result of neutrophil phagocytosis were assessed., Results: A total of 32 AML patients were randomized to receive per oral supplementation of channa striata extract (6 g/day) or nutrition from the hospital during intensive chemotherapy and after chemotherapy. The median onset of neutropenia was 6.1 + 3.37 in the channa striata extract group and 8.8 + 4.59 in the control group (p=0.109). The median duration of neutropenia was 12.8 + 6.20 d in the channa striata group and 17.2 + 11.06 d in the control group (p=0.281), whereas the incidence of febrile neutropenia were 85,7% in the channa striata extract group and 43,8% in the control group with median duration of neutropenic fever were 5.7 + 3.56 and 4.7 + 4.57, respectively. The chi-square test in the IL-6 delta category showed a tendency for IL-6 levels to rise in 61.5% of subjects in the Channa striata group compared to the control group (p=0.182)., Conclusion: Channa striata extract supplementation did not influence neutropenia onset, duration, neutrophil function, or neutropenic fever in AML patients.

Exposure to nanoparticles (NPs) is frequently associated with adverse cardiovascular effects. In contrast, NPs in nanomedicine hold great promise for precise lung-specific drug delivery, especially considering the extensive pulmonary capillary network that facilitates interactions with bloodstream-suspended particles. Therefore, exact knowledge about effects of engineered NPs within the pulmonary microcirculation are instrumental for future application of this technology in patients. To unravel the real-time dynamics of intravenously delivered NPs and their effects in the pulmonary microvasculature, we employed intravital microscopy of the mouse lung. Only PEG-amine-QDs, but not carboxyl-QDs triggered rapid neutrophil recruitment in microvessels and their subsequent recruitment to the alveolar space and was linked to cellular degranulation, TNF-α, and DAMP release into the circulation, particularly eATP. Stimulation of the ATP-gated receptor P2X7R induced expression of E-selectin on microvascular endothelium thereby mediating the neutrophilic immune response. Leukocyte integrins LFA-1 and MAC-1 facilitated adhesion and decelerated neutrophil crawling on the vascular surface. In summary, this study unravels the complex cascade of neutrophil recruitment during NP-induced sterile inflammation. Thereby we demonstrate novel adverse effects for NPs in the pulmonary microcirculation and provide critical insights for optimizing NP-based drug delivery and therapeutic intervention strategies, to ensure their efficacy and safety in clinical applications., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Neutrophils, pivotal cells of innate and adaptive immune responses, employ reactive oxygen species (ROS) to combat pathogens and control gene expression. Paracetamol (acetaminophen) is widely used as an analgesic and antipyretic medication, yet its precise mechanisms of action are not yet fully understood. Here, we investigate the impact of both ingested and in-vitro paracetamol on neutrophil ROS activity, using flow cytometry and antioxidant assays. Our studies reveal that paracetamol significantly suppresses ROS activity ex-vivo in the short term. Additionally, both paracetamol and its metabolite N-acetyl-p-benzoquinone imine exhibited direct in vitro antioxidant effects, and paracetamol suppressed neutrophil extracellular trap formation ex vivo. These findings suggest a connection between paracetamol use and altered neutrophil responses, with potential implications for use in some patient groups, such as immunocompromised individuals. Further investigation into paracetamol's effects on neutrophil antimicrobial functions is warranted to elucidate possible risks, particularly when taken frequently or in conjunction with other treatments such as vaccinations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: Periodontitis is an inflammatory and destructive disease caused by dental plaque, which can result in the immune microenvironment disorders and loss of periodontal support tissue. In order to promote the restoration of local microenvironment stability, a functional biomaterial Gelatin methacryloyl @MP196/exos based on characteristics of disease occurrence is designed., Methods: Transmission electron microscopy, nanosight particle tracking analysis and western blot analysis were applied to prove the presence of exos in GelMA@MP196/exos. The swelling and degradation rates of GelMA@MP196/exos were evaluated. Cell proliferation, antibacterial ability and cellular uptake and intracellular internalization of exos were assessed in the study. Efferocytosis and M2 polarization of macrophages was estimated and the effects of GelMA@MP196/exos were proved in vivo., Results: GelMA@MP196/exos upregulated the expression of genes and proteins related to neutrophil apoptosis and promoted neutrophil apoptosis, macrophage M2 polarization, and efferocytosis. Furthermore, GelMA@MP196/exos exhibited significant antibacterial activity against Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis. GelMA@MP196/exos alleviated periodontitis and reduced alveolar bone loss in vivo in rat models., Conclusions: GelMA@MP196/exos can serve as a potential strategy for the treatment of periodontitis., Clinical Significance: The main aim of periodontal therapy is to remove dental plaque and eliminate inflammation. However, some patients with low plaque scores and insufficient neutrophil clearance, resulting in poor responsiveness to periodontal therapy. Under the circumstances, local Application of drug that regulate the immune microenvironment had significance in controlling the progression of inflammation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Bone defects present significant challenges in clinical contexts, particularly among the elderly, and are often linked to altered innate immune responses; however, underlying mechanisms remain to be understood. This study investigates immune changes in early bone healing in aged mice, emphasizing the effects of zinc in modulating inflammatory processes. By exploring the role of zinc and NETosis in this process, we seek to develop novel therapeutic strategies that could improve bone repair in aging populations. Critical-sized calvarial bone defects were induced in young (8-week-old) and aged (18-month-old) mice, with RNA sequencing analysis. Zinc oxide nanoparticle-infused polycaprolactone (ZnPCL) scaffolds were then fabricated using electrospinning, and their effects on intracellular zinc levels, NETosis, M2 polarization, and bone formation were assessed through in vitro and in vivo experiments. In aged mice, bone healing was delayed, inflammation was prolonged, and NETosis was excessive. RNA sequencing identified alterations in zinc ion transport genes, alongside excessive NETosis. Aged mouse neutrophils exhibited low intracellular zinc levels. ZnPCL fibers effectively reduced NETosis and inflammation, promoted M2 macrophage polarization, and enhanced new bone formation, thereby improving bone healing in aged mice. This study demonstrates that ZnO nanoparticle-infused biomaterials, ZnPCL, effectively deliver zinc to neutrophils, reduce NETosis, promote M2 polarization, and enhance bone healing in aged mice.

Background: Oncostatin M (OSM) is involved in several inflammatory responses. Tryptanthrin (TRYP), as a natural alkaloid, is a bioactive compound derived from indigo plants. Objectives/ Methods: The purpose of this study is to investigate the potential inhibitory activity of TRYP on OSM release from neutrophils using neutrophils-like differentiated (d)HL-60 cells and neutrophils from mouse bone marrow., Results: The results showed that TRYP reduced the production and mRNA expression levels of OSM in the granulocyte-macrophage colony-stimulating factor (GM-CSF)-stimulated neutrophils-like dHL-60 cells. In addition, TRYP decreased the OSM production levels in the GM-CSF-stimulated neutrophils from mouse bone marrow. TRYP inhibited the phosphorylation of phosphatidylinositol 3-kinase (PI3K), AKT, and nuclear factor (NF)-κB in the GM-CSF-stimulated neutrophils-like dHL-60 cells., Conclusions: Therefore, these results reveal for the first time that TRYP inhibits OSM release via the down-regulation of PI3K-AKT-NF-κB axis from neutrophils, presenting its potential as a therapeutic agent for inflammatory responses.

Neutrophil-mediated inflammation is a key feature of immune-mediated chronic skin disorders, but the mechanistic understanding of neutrophil involvement in these conditions remains incomplete. Dapsone, colchicine, and tetracyclines are established drugs within the dermatologist's therapeutic armamentarium that are credited with potent anti-neutrophilic effects. Anti-neutrophilic drugs have established themselves as versatile agents in the treatment of a wide range of dermatological conditions. Some of these agents are approved for the management of specific dermatologic conditions, but most of their current uses are off-label and only supported by isolated reports or case series. Their anti-inflammatory and immunomodulatory properties make them particularly valuable in managing auto-immune bullous diseases, neutrophilic dermatoses, eosinophilic dermatoses, interface dermatitis, and granulomatous diseases that are the focus of this review. By inhibiting inflammatory pathways, reducing cytokine production, and modulating immune responses, they contribute significantly to the treatment and management of these complex skin conditions. Their use continues to evolve as our understanding of these diseases deepens, and they remain a cornerstone of dermatological therapy.

Production of specialized proresolving mediators (SPMs) during the resolution phase in the acute inflammatory response is key to orchestrating complete resolution. Here, we uncovered a trihydroxy resolvin in fresh human saliva. We identified and determined its complete stereochemistry as 7S,16R,17R-trihydroxy-4Z,8E,10Z,12E,14E,19Z-docosahexaenoic acid (17R-RvD2) using total organic synthesis and matching of physical properties. The 17R-RvD2 was produced by activated human M2-like macrophages, M1-like macrophages, and human peripheral blood monocytes. 17R-RvD2 displayed potent proresolving functions (picomolar to nanomolar). Topical application of 17R-RvD2 on mouse ear skin reduced neutrophilic infiltration (~50%). 17R-RvD2 increased M2 markers CD206 and CD163 on human monocyte-derived macrophages and enhanced efferocytosis of senescent red blood cells by M2-like macrophages (EC 50 ~ 2.6 × 10 -14 M). In addition, 17R-RvD2 activated the RvD2 receptor and was equipotent to its epimer RvD2. 17R-RvD2 also significantly increased phagocytosis of Escherichia coli by human neutrophils. Together, these results establish the complete stereochemistry and potent proresolving functions of the previously unknown 17R-RvD2.

Cystic fibrosis (CF) is characterized by chronic airway obstruction, infection, and inflammation leading to progressive loss of lung function and eventual respiratory failure. Omadacycline, a tetracycline antibiotic, demonstrates in vitro activity against key CF pathogens, substantial lung penetration, and increasing clinical evidence for the treatment of lung infections in people with CF (PwCF). Preliminary in vitro data demonstrate that omadacycline exhibits anti-inflammatory activity. This study aims to determine the anti-inflammatory effects of omadacycline in vitro and in a murine model of lipopolysaccharide (LPS)-induced lung neutrophilia. In vitro , THP-1-derived macrophages were treated with omadacycline (20-100 µg/mL) 30 minutes prior to LPS stimulation. Pro-inflammatory cytokine (TNF-α, IL-1β/6), chemokine (CXCL-1/2), and MMP-9 levels were analyzed after 24 hours by ELISA. Omadacycline's effects on IL-8-induced human neutrophil chemotaxis were also investigated. In vivo , omadacycline (2.5-30 mg/kg), comparators dexamethasone (1 mg/kg), and azithromycin (30 mg/kg) were administered 1 hour before and 6 hours after intranasal LPS challenge, respectively. Leukocyte counts and differentials in bronchoalveolar lavage fluid (BALF), inflammatory mediator levels in BALF and lung homogenates, pulmonary edema markers, and the severity of lung injury were evaluated 24 hours or 48 hours post-challenge. Treatment with omadacycline in vitro resulted in significant, dose-dependent reductions in IL-6, CXCL-1, and MMP-9 expression and inhibition of IL-8-induced neutrophil chemotaxis. In vivo , omadacycline yielded protective and therapeutic effects by reducing the production of proinflammatory cytokines and chemokines and neutrophil infiltration into the lungs, along with modestly improving lung injury severity. These preclinical results suggest that omadacycline may provide dual anti-bacterial and anti-inflammatory activities relevant to chronic lung infection treatment in PwCF.IMPORTANCENontuberculous mycobacteria, particularly Mycobacterium abscessus complex (MABSC), are a major concern for people with cystic fibrosis (PwCF) due to their association with deteriorating lung function. A substantial barrier to effective treatment is the limited number of safe and effective antibiotics. Omadacycline offers a potential advancement in managing MABSC infections in cystic fibrosis due to its activity, effective penetration into pulmonary secretions, improved tolerability, and good oral bioavailability as shown in healthy volunteers. Our study is the first to explore omadacycline's effects in a model of sterile lung inflammation and acute lung injury. We found that omadacycline not only has potent anti-bacterial properties but also exhibits anti-inflammatory effects, reducing lung inflammation and injury in our preclinical models. These findings underscore omadacycline's potential as a dual-action therapy for lung infections in PwCF, indicating significant potential to improve patient outcomes and guide more effective antimicrobial therapy decisions., Competing Interests: The authors declare no conflict of interest.

Aromadendrin (ARO) is an active plant compound that exerts anti-inflammatory effects. However, its ameliorative effects on chronic obstructive pulmonary disease (COPD) remain unclear. Therefore, we investigated the inhibitory effects of ARO on bronchial inflammation using an experimental model of COPD. In vivo analysis confirmed a notable increase in the number of neutrophils/macrophages and the formation of reactive oxygen species (ROS), myeloperoxidase (MPO), interleukin (IL)-6/IL-1β, and monocyte chemoattractant protein (MCP)-1 in the bronchoalveolar lavage (BAL) fluid of COPD mice, which was attenuated by oral gavage of ARO. In addition, hematoxylin and eosin staining showed a notable cell influx in the lungs of the COPD group, which was ameliorated by ARO. Western blotting revealed that ARO decreased the upregulation of neutrophil elastase expression in the lungs of the COPD group. Furthermore, periodic acid-Schiff staining showed that increased mucus formation in the lungs of the COPD group was downregulated by ARO. ARO also blocked CREB activation in the lungs of COPD mice. This in vivo, anti-inflammatory effect of ARO was accompanied by its modulatory effect on the activation of the MAPK/NF-κB/NLRP3 inflammasome. In summary, our study demonstrated that ARO has protective effects on bronchial inflammation by attenuating immune cell accumulation, toxic molecule/cytokine/chemokine formation, and MAPK/NF-κB/NLRP3 inflammasome activation, suggesting the potential development of ARO as an adjuvant for the prevention and treatment of COPD.

Background: WHIM (Warts, Hypogammaglobulinemia, Infections, and Myelokathexis) syndrome is an ultra-rare, combined primary immunodeficiency and chronic neutropenic disorder characterized by a range of clinical presentations, including peripheral neutropenia, lymphopenia, and recurrent infections. WHIM syndrome is most often caused by gain-of-function mutations in the gene encoding C-X-C chemokine receptor 4 (CXCR4). As such, inhibition of CXCR4 with XOLREMDI ® (mavorixafor), an orally bioavailable CXCR4 antagonist, demonstrated clinically meaningful increases in absolute neutrophil and lymphocyte counts and concomitant reduction in infections in patients with WHIM syndrome, resulting in its recent U.S. Food and Drug Administration approval. The impact of CXCR4 antagonism on other aspects of the pathobiology in WHIM syndrome, such as lymphopoiesis and leukocyte trafficking between primary and secondary lymphoid organs, is less understood., Methods: In the current study, the effects of CXCR4 antagonism on leukocyte trafficking and distribution in primary and secondary lymphoid organs were investigated in a mouse model of WHIM syndrome carrying the heterozygous Cxcr4 1013 mutation. Cxcr4 +/1013 and Cxcr4 wild-type mice received the orally bioavailable CXCR4 antagonist X4-185. Blood, spleen and bone marrow samples were collected for numeration, flow cytometry, and functional studies., Results: Cxcr4 +/1013 mice exhibited profound peripheral blood leukopenia as seen in patients with WHIM syndrome. CXCR4 antagonism corrected circulating leukopenia and mobilized functional neutrophils without disrupting granulopoiesis in the bone marrow of Cxcr4 +/1013 mice. Furthermore, Cxcr4 +/1013 displayed aberrant splenic T and B-cell counts and frequency. Treatment with X4-185 normalized splenic T-cell abnormalities, correcting the reduced CD8 + T-cell numbers, restoring the CD4/CD8 T-cell ratio, and ameliorating peripheral blood T-cell lymphopenia. In addition, CXCR4 antagonism was able to correct the abnormal frequencies and numbers of splenic marginal zone and follicular B cells in Cxcr4 +/1013 mice, and ultimately normalize B-cell lymphopenia in the peripheral circulation., Conclusions: Our study provides comprehensive evidence that oral dosing with a CXCR4 antagonist can effectively correct WHIM-associated neutrophil and lymphocyte abnormalities in a mouse model of WHIM syndrome. These findings extend our understanding of how targeting the dysregulated CXCR4 signaling pathway can ameliorate the pathogenesis of WHIM syndrome., Competing Interests: CN, KZ, HM, BM, RJ, and AT are employees and shareholders of X4 Pharmaceuticals. LR, MKh, MKa, BS, VG, VR, ZA, ME and KB had a research agreement with X4 Pharmaceuticals. The handling editor TT declared a past collaboration with the authors KZ and AT., (Copyright © 2024 Roland, Nguyen, Zmajkovicova, Khamyath, Kalogeraki, Schell, Gourhand, Rondeau, Abou Nader, Monticelli, Maierhofer, Johnson, Taveras, Espéli and Balabanian.)

Radiation-induced lung injury (RILI) initiates radiation pneumonitis and progresses to fibrosis as the main side effect experienced by patients with lung cancer treated with radiotherapy. There is no effective drug for RILI. Sustained vascular activation is a major contributor to the establishment of chronic disease. Here, using a whole thoracic irradiation (WTI) mouse model, we investigated the mechanisms and effectiveness of thrombopoietin mimetic (TPOm) for preventing RILI. We demonstrated that administering TPOm 24 hours before irradiation decreased histologic lung injury score, apoptosis, vascular permeability, expression of proinflammatory cytokines, and neutrophil infiltration in the lungs of mice 2 weeks after WTI. We described the expression of c-MPL, a TPO receptor, in mouse primary pulmonary microvascular endothelial cells, showing that TPOm reduced endothelial cell-neutrophil adhesion by inhibiting ICAM-1 expression. Seven months after WTI, TPOm-treated lung exhibited less collagen deposition and expression of MMP-9, TIMP-1, IL-6, TGF-β, and p21. Moreover, TPOm improved lung vascular structure, lung density, and respiration rate, leading to a prolonged survival time after WTI. Single-cell RNA sequencing analysis of lungs 2 weeks after WTI revealed that TPOm shifted populations of capillary endothelial cells toward a less activated and more homeostatic phenotype. Taken together, TPOm is protective for RILI by inhibiting endothelial cell activation.

Myocardial ischemia/reperfusion injury (MI/RI) generates reactive oxygen species (ROS) and initiates inflammatory responses. Traditional therapies targeting specific cytokines or ROS often prove inadequate. An innovative drug delivery system (DDS) is developed using neutrophil decoys (NDs) that encapsulate 18β-glycyrrhetinic acid (GA) within a hydrolyzable oxalate polymer (HOP) and neutrophil membrane vesicles (NMVs). These NDs are responsive to hydrogen peroxide (H 2 O 2 ), enabling controlled GA release. Additionally, NDs adsorb inflammatory factors, thereby reducing inflammation. They exhibit enhanced adhesion to inflamed endothelial cells (ECs) and improved penetration. Once internalized by cardiomyocytes through clathrin-mediated endocytosis, NDs protect against ROS-induced damage and inhibit HMGB1 translocation. In vivo studies show that NDs preferentially accumulate in injured myocardium, reducing infarct size, mitigating adverse remodeling, and enhancing cardiac function, all while maintaining favorable biosafety profiles. This neutrophil-based system offers a promising targeted therapy for MI/RI by addressing both inflammation and ROS, holding potential for future clinical applications., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Background: Periodontitis is a chronic inflammatory disease characterized by the destruction of the components of the periodontium. It significantly impacts oral health and has been linked to systemic conditions like cardiovascular disease and diabetes. The critical role of neutrophils in the occurrence and development of chronic periodontitis has been paid increasing attention. The study aimed to explore the protective effects of D-mannose on chronic periodontitis and determine whether its underlying mechanisms is related to neutrophils., Methods: To explore the protective effects of D-mannose on chronic periodontitis, the eight-week-old Sprague Dawley rat model of lipopolysaccharide (LPS)-induced periodontitis was established, followed by D-mannose treatment by oral gavage. To evaluate the protective effects of D-mannose against periodontal bone loss, methylene blue staining, hematoxylin and eosin (H&E) staining, and micro-CT scanning were utilized. Then, immunofluorescence (IF), Western Blot, and RT-PCR were applied to assess the expression levels of pro-inflammatory cytokines (IL-1β, IL-6, and IL-17), anti-inflammatory cytokine (IL-10), tumor necrosis factor-alpha (TNF-α), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), ten-eleven translocation 2 (TET2), and key glycolytic enzymes (HK1, HK2, PFKFB3), and to examine D-mannose's impact on the recruitment and activation of neutrophils in the gingiva. Additionally, neutrophils isolated from the peripheral blood of healthy rats were treated with LPS and D-mannose, and changes in the expression levels of myeloperoxidase (MPO), IL-1β, IL-6, IL-17, IL-10, and TET2 were observed via IF., Results: In vivo, D-mannose inhibited LPS-induced alveolar bone resorption in rats. After D-mannose treatment, the expression levels of IL-17 (p<0.01) and TET2 (p<0.01) were suppressed by IF, and the expression levels of IL-1β (p<0.05), IL-17 (p<0.05) and TET2 (p<0.01) were downregulated by WB. The results of qPCR showed that D-mannose reduced the expression levels of IL-1β (p<0.05), IL-6 (p<0.01), IL-17 (p<0.01), TNF-α (p<0.01), G-CSF (p<0.01), GM-CSF (p<0.01), TET2 (p<0.01), HK1 (p<0.01), HK2 (p<0.01), and PFKFB3 (p<0.01). D-mannose also inhibited the recruitment and activation of neutrophils in LPS-treated rat gingival tissues. In vitro, the results of IF showed that D-mannose inhibited the activation of neutrophils stimulated by LPS, downregulated the expression of IL-1β (p < 0.05), IL-6, IL-17 (p < 0.01), and TET2 (p < 0.01), and upregulated the expression of IL-10 (p < 0.01)., Conclusions: D-mannose can alleviate chronic periodontitis in rats by regulating the functions of neutrophils, potentially associated with the expression of TET2 and glycolysis, providing new insights into the potential application of D-mannose to chronic periodontitis., (© 2024. The Author(s).)

Creating a versatile and remotely self-assembling biocomposite for delivering therapeutics to alleviate inflammatory diseases poses significant challenges. This study introduces a novel biocomposite, created through cold-atmosphere plasma treatment, that combines fucoidan (Fu) and neutrophil lysate (Nu) to mediate the self-assembly of diferuloylmethane (DIF) and iron oxide (IO) nanoclusters, termed DIF-Nu/Fu-IO NC. This biocomposite forms a phototherapeutic and magnetically-driven in situ gel with open-porous architecture loaded with DIF, offering non-invasive theranostic capabilities for treating inflammatory diseases. It demonstrates efficacy in both an intraarticular zymosan-induced rheumatoid arthritis animal model and an intranasal LPS-induced inflammatory lung model. Upon administration, near-infrared (NIR) irradiation and magnet application significantly improved the condition of the animals with rheumatoid arthritis and lung inflammation. This breakthrough heralds a new paradigm in bioinspired, versatile, theranostic, self-assembling biocomposites for addressing clinical inflammatory diseases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Exposure to air pollution poses a risk to human respiratory health, and a preventive and therapeutic remedy against fine dust-induced respiratory disease is needed., Background/objectives: The respiratory-protective effects of Lysimachia mauritiana (LM) against airway inflammation were evaluated in a mouse model exposed to a fine dust mixture of diesel exhaust particles and particulate matter with a diameter of less than 10 µm (PM10D)., Methods: To induce airway inflammation, PM10D was intranasally injected into BALB/c mice three times a day for 12 days, and LM extracts were given orally once per day. The immune cell subtypes, histopathology, and expression of inflammatory mediators were analyzed from the bronchoalveolar lavage fluid (BALF) and lungs., Results: LM alleviated the accumulation of neutrophils and the number of inflammatory cells in the lungs and the BALF of the PM10D-exposed mice. LM also reduced the release of inflammatory mediators (MIP-2, IL-17, IL-1α, CXCL1, TNF-α, MUC5AC, and TRP receptor channels) in the BALF and lungs. Lung histopathology was used to examine airway inflammation and the accumulation of collagen fibers and inflammatory cells after PM10D exposure and showed that LM administration improved this inflammation. Furthermore, LM extract inhibited the MAPK and NF-κB signaling pathway in the lungs and improved expectoration activity through an increase in phenol red release from the trachea., Conclusions: LM alleviated PM10D-exposed neutrophilic airway inflammation by suppressing MAPK/NF-κB activation. This study indicates that LM extract may be an effective therapeutic agent against inflammatory respiratory diseases.

Background: Systemic Lupus Erythematosus (SLE) is characterized by dysregulated immune responses, with neutrophil extracellular traps (NETs) playing a significant role. NETs are recognized by autoantibodies in SLE patients, exacerbating pathology. Both excessive NET formation and impaired degradation contribute to SLE pathophysiology., Objective: To investigate the immunomodulatory effects of Dexamethasone-primed Wharton's jelly (WJ) derived MSCs CM (DW) and IFN-γ-primed WJ-MSCs-CM (IW) on NETosis and associated protein markers in SLE patients' LPS or ribonucleoprotein immune complexes (RNP ICs) induced neutrophils and in pristane induced lupus (PIL) model. And to elucidate the mechanism involved therein., Methods: We investigated the immunomodulatory effects of DW and IW on NETosis in SLE. Utilizing ex vivo and in vivo models, we assessed the impact of preconditioned media on NET formation and associated protein markers neutrophil elastase (NE), citrullinated histone (citH3), myeloperoxidase (MPO), cytoplasmic and mitochondrial ROS production. We also examined the involvement of key immunomodulatory factors present in DW and IW, including prostaglandin E2 (PGE2), indoleamine 2,3-dioxygenase (IDO), and transforming growth factor-beta (TGF-β)., Results: Preconditioned media effectively suppressed NETosis and reduced ROS generation in SLE neutrophils, indicating their immunomodulatory potential. Inhibition studies implicated IDO and PGE2 in mediating this effect. Combined treatment with DW or IW together with hydroxychloroquine (HCQ) demonstrated superior efficacy over HCQ alone, a standard SLE medication. In PIL mouse model, DW and IW treatments reduced NETosis, ROS generation, as evidenced by decreased NET-associated protein expression in vital organs., Conclusion: Our study highlights the multifaceted impact of IW and DW on NETosis, ROS dynamics, and lupus severity in SLE. These findings underscore the potential of preconditioned media for the development of targeted, personalized approaches for SLE treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Priya, Thacker, Chaubey, Rai, Singh, Rawat, Giri, Mohanty and Rai.)

TNF inhibitors have been used to treat autoimmune and autoinflammatory diseases. Here we report an unexpected mechanism underlying the therapeutic effects of TNF inhibitors in Behçet's disease (BD), an autoimmune inflammatory disorder. Using serum metabolomics and peripheral immunocyte transcriptomics, we find that polymorphonuclear neutrophil (PMN) from patients with BD (BD-PMN) has dysregulated mevalonate pathway and subsequently increased farnesyl pyrophosphate (FPP) levels. Mechanistically, FPP induces TRPM2-calcium signaling for neutrophil extracellular trap (NET) and proinflammatory cytokine productions, leading to vascular endothelial inflammation and damage. TNF, but not IL-1β, IL-6, IL-18, or IFN-γ, upregulates TRPM2 expression on BD-PMN, while TNF inhibitors have opposite effects. Results from mice with PMN-specific FPP synthetase or TRPM2 deficiency show reduced experimental vasculitis. Meanwhile, analyses of public datasets correlate increased TRPM2 expressions with the clinical benefits of TNF inhibitors. Our results thus implicate FPP-TRPM2-TNF/NETs feedback loops for inflammation aggravation, and novel insights for TNF inhibitor therapies on BD., (© 2024. The Author(s).)