The CURB65 score predicted 180-day mortality of non-small cell lung carcinoma patients with immune checkpoint inhibitor-associated pneumonitis: A pilot retrospective analysis.

Introduction: The immune checkpoint inhibitor-associated pneumonitis (CIP) is a particularly worrisome and potentially lethal form of immune-related adverse events. An objective and evidence-based assessment tool for evaluating the severity of CIP is in urgent need. CURB65 (consciousness, urea nitrogen, respiratory rate, blood pressure, and age) is a potential candidate to meet the need. Methods: A retrospective study was conducted to explore preliminarily if CURB65 could predict the mortality in non-small cell lung carcinoma (NSCLC) patients with CIP. Results: A total number of 28 NSCLC patients with CIP were included in the current study and classified into low-CURB65 group (n = 21) and high-CURB65 group (n = 7). Mortality after onset of CIP was consistently higher in the high-CURB65 group than in the low-CURB65 group (30-day: 57.1% vs. 0; 90-day: 71.4% vs. 4.76%; 180-day:71.4% vs. 14.29%). Two patients (9.5%) in the low-CURB65 group had severe CIP, and more than half of patients in the high-CURB65 group had severe CIP (p = 0.0008). The patients in the high-CURB65 group received more aggressive treatment. Both groups showed a predominant organizing pneumonia-like pattern on CT scan. CURB65 was moderately correlated with the American Society of Clinical Oncology (ASCO) grade of CIP, with a Pearson correlation coefficient R of 0.524. Conclusion: CURB65 accurately stratified the risk of mortality in NSCLC patients with CIP. CURB65 might complement the ASCO grade in the assessment and prediction of mortality in these populations.

Downregulated long intergenic non-coding RNA 00,174 represses malignant biological behaviors of lung cancer cells by regulating microRNA-584-3p/ribosomal protein S24 axis.

The detailed regulatory mechanism of LINC00174 in lung cancer (LC) development remains largely unknown. This research was designed to probe into the impacts of LINC00174 in LC cells through modulating the microRNA (miR)-584-3p/ribosomal protein S24 (RPS24) axis. LINC00174, miR-584-3p, and RPS24 expression levels in LC cells and tissues were examined. The constructs altering LINC00174, miR-584-3p, or RPS24 expression were transfected into LC cells to examine the malignant phenotypes of LC cells. The relations among LINC00174, miR-584-3p, and RPS24 were validated. LINC00174 and RPS24 were high-expressed while miR-584-3p was low-expressed in LC. Downregulated LINC00174 or RPS24 or upregulated miR-584-3p inhibited the malignant biological behaviors of LC cells. The silenced miR-584-3p could reverse the repressive effects of reduced LINC00174 on the development of LC cells; while RPS24 overexpression inverted the repressive effects of miR-584-3p elevation on LC cells. Mechanically, LINC00174 bound to miR-584-3p that targeted RPS24. Repressed LINC00174 can relieve the malignant phenotypes of LC cells via modulating the miR-584-3p/RPS24 axis.

Circular RNA circ_0061140 accelerates hypoxia-induced glycolysis, migration, and invasion in lung adenocarcinoma through the microRNA-653/hexokinase 2 (HK2) axis.

Circular RNA (circRNA) is considered to be an essential regulator of multiple human malignancies. However, the role and molecular mechanism of circ_0061140 in lung adenocarcinoma ((LUAD) remain elusive. The levels of circ_0061140, microRNA (miR)-653 and hexokinase 2 (HK2) were examined by RT-qPCR. Downstream targets of circ_0061140 were predicted by circinteractome website and verified by luciferase reporter and RIP assays. HK2 protein level was assessed via Western blotting. The migratory and invasive abilities of LUAD cells were assessed via wound healing and transwell assays. It was uncovered that circ_0061140 level was elevated in LUAD samples, and the high level of circ_0061140 was related to poor survival rate of LUAD patients. Circ_0061140 deletion inhibited glycolysis, migration and invasion of hypoxia-treated LUAD cells. Moreover, circ_0061140 could modulate HK2 level by absorbing miR-653. Furthermore, miR-653 silence or HK2 addition neutralized the effects of circ_0061140 knockdown on LUAD progression under hypoxia. This study elaborated that circ_0061140 accelerated hypoxia-triggered glycolysis, migration and invasion in LUAD cells via downregulating miR-653 and increasing HK2 expression.

Oxymatrine inhibits the pyroptosis in rat insulinoma cells by affecting nuclear factor kappa B and nuclear factor (erythroid-derived 2)-like 2 protein/heme oxygenase-1 pathways.

As the mechanism underlying glucose metabolism regulation by oxymatrine is unclear, this study investigated the effects of oxymatrine on pyroptosis in INS-1 cells. Flow cytometry was employed to examine cell pyroptosis and reactive oxygen species (ROS) production. Cell pyroptosis was also investigated via transmission electron microscopy and lactate dehydrogenase (LDH) release. Protein levels were detected using western blotting and interleukin (IL)-1ß and IL-18 secretion by enzyme-linked immunosorbent assay. The caspase-1 activity and DNA-binding activity of nuclear factor kappa B (NF-κB) and nuclear factor (erythroid-derived 2)-like 2 protein (Nrf2) were also assessed. In the high glucose and high fat-treated INS-1 cells (HG + PA), the caspase-1 activity and LDH content, as well as Nod-like receptor family pyrin domain containing 3, Gsdmd-N, caspase-1, apoptosis-associated speck-like protein containing a CARD, IL-1ß, and IL-18 levels were increased. Moreover, P65 protein levels increased in the nucleus but decreased in the cytoplasm. Oxymatrine attenuated these effects and suppressed high glucose and high fat-induced ROS production. The increased levels of nuclear Nrf2 and heme oxygenase-1 (HO-1) in the HG + PA cells were further elevated after oxymatrine treatment, whereas cytoplasmic Nrf2 and Keleh-like ECH-associated protein levels decreased. Additionally, the elevated transcriptional activity of p65 in HG + PA cells was reduced by oxymatrine, whereas that of Nrf2 increased. The results indicate that the inhibition of pyroptosis in INS-1 cells by oxymatrine, a key factor in its glucose metabolism regulation, involves the suppression of the NF-κB pathway and activation of the Nrf2/HO-1 pathway.

Gap between risk factors and prevention strategies? A nationwide survey of fall prevention among medical and surgical patients.

AIMS: This study aimed to determine the extent to which nurses report assessing evidence-based falls risk factors and implementing targeted prevention for medical and surgical patients in China. DESIGN: This study was a national online survey. METHODS: The respondents were registered nurses working in medical and surgical units in 662 Chinese hospitals. The data concerning the falls risk factor assessments and targeted interventions implemented by nurses were collected online by the Nursing Management Committee of the Chinese Nursing Association in China in 2019. RESULTS: In total, 68 527 valid questionnaires were returned (95.0%). In medical and surgical units, nurses were most likely to report assessing balance, mobility and strength (81.6%) and orthostatic hypotension (76.4%) in falls patients and least likely to report assessing continence (61.3%) and feet and footwear (55.8%). Ensuring the use of appropriate footwear (79.3%) and managing syncope, dizziness and vertigo (73.8%) were the most common multiple interventions, while managing postural hypotension (48.8%) and cognitive impairment (48.4%) was the least common. Nine falls risk factors with clearly matched multifactorial interventions were identified in medical and surgical units (68.2%-97.1%). CONCLUSIONS: The implementation of multifactorial interventions in medical and surgical wards is inconsistent as reported by nurses in medical and surgical wards. Throughout China, nurses are generally concerned about falls risk factors and prevention for their patients; however, limited attention has been focused on continence, feet and footwear assessment and the management of cognitive impairment. Evidence-based falls prevention should be further tailored to the specific risk factors of each patient. IMPACT: Best practice guidelines for falls prevention in hospitals have been developed and published, and it is important for nurses to use these guidelines to guide practice. Our findings identify that in routine care, healthcare providers and hospitals can prevent falls.

EGFR-Mutated Squamous Cell Lung Cancer and Its Association With Outcomes.

BACKGROUND: The therapeutic efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced EGFR-mutant lung squamous cell carcinoma (SCC) patients remains uncertain. Furthermore, the factors underlying the responsiveness have not been fully investigated. We therefore investigated the link between genomic profiles and EGFR-TKI efficacy. MATERIAL AND METHODS: We consecutively enrolled stage IV, EGFR-mutant, and EGFR-TKI-treated patients with SCC. Patients with EGFR wild-type lung SCC and EGFR-mutant lung adenocarcinoma were consecutively enrolled as controls, and next-generation sequencing (NGS) was performed. RESULTS: In total, 28 EGFR-mutant lung SCC, 41 EGFR-mutant lung adenocarcinoma, and 40 EGFR wild-type lung SCC patients were included. Among the patients with EGFR mutations, shorter progression-free survival (PFS) was observed in SCC compared to adenocarcinoma (4.6 vs. 11.0 months, P<0.001). Comparison of the genomic profiles revealed that EGFR-mutant SCC patients had similar mutation characteristics to EGFR-mutant adenocarcinoma patients, but differed from those with EGFR wild-type SCC. Further exploration of EGFR-mutant SCC revealed that mutations in CREBBP (P = 0.005), ZNF217 (P = 0.016), and the Wnt (P = 0.027) pathway were negatively associated with PFS. Mutations in GRM8 (P = 0.025) were associated with improved PFS. CONCLUSIONS: EGFR-mutant lung SCC has a worse prognosis than EGFR-mutant adenocarcinoma. Mutations in other genes, such as CREBBP, ZNF217, GRM8, or Wnt that had implications on PFS raise the possibility of understanding mechanisms of resistance to EGFR-TKI in lung SCC, which will aid identification of potential beneficial subgroups of patients with EGFR-mutant SCCs receiving EGFR-TKIs.

The Application of Combined Immune Checkpoint Inhibitor Modalities in Previously Treated Non-Small Cell Lung Cancer Patients and the Associations Thereof With the Lung Immune Prognostic Index.

BACKGROUND: Immune checkpoint inhibitor (ICI) monotherapy remains the standard of care for patients with previously treated non-small cell lung cancer. However, few reports have compared the clinical benefits of second-line ICIs alone with those of ICIs combined with other therapies, including anti-angiogenesis therapy or chemotherapy. METHODS: Patients with previously treated advanced non-small cell lung cancer who received ICIs were retrospectively reviewed. The progression-free survival (PFS), overall survival, objective response rate, disease control rate, and safety were assessed. Complete blood cell counts and serum lactate dehydrogenase (LDH) levels were measured before and after ICI treatment. RESULTS: Of 120 patients, 75 were treated with ICI monotherapy, 26 with ICIs plus anti-angiogenic therapy (ICI+A), and 19 with ICIs plus chemotherapy (ICI+C). The objective response rate was significantly higher in the ICI+C group (57.9%) than ICI monotherapy (26.3%) and ICI+A (31.8%) groups. The depth of response was significantly greater in the ICI+C (-35.1%) than ICI+A (-2.04%) and ICI monotherapy (3.963%) groups. ICI+C afforded a better PFS compared with the ICI monotherapy and ICI+A groups (8.5 vs. 4.6 and 4.1 months, respectively). Notably, the pre- and post-treatment peripheral neutrophil/lymphocyte ratios and serum LDH levels were negatively correlated with the PFS of the entire cohort. More importantly, the pretreatment lung immune prognostic index (neutrophil/lymphocyte ratio ≥ 4 and LDH level ≥ upper limit of normal) satisfactorily predicted the responses to ICI-based strategies. Adverse events (AEs) occurred in 65.3%, 92.3%, and 94.7% of patients in the ICI monotherapy, ICI+A, and ICI+C groups, respectively. Grade 3-5 AEs were more common in the combination therapy groups (ICI+A, 19.2%; ICI+C, 21%; ICI monotherapy, 4%). CONCLUSION: In second-line settings and beyond, ICIs combined with chemotherapy prolonged survival, with tolerable AEs. Addition of anti-angiogenic agents to ICIs did not afford any additional benefits. Further prospective studies are warranted.

Voltage-gated potassium channels are involved in oxymatrine-regulated islet function in rat islet ß cells and INS-1 cells.

OBJECTIVES: Oxymatrine can regulate glucose metabolism. But the underlying mechanisms remain unclear. We investigated the relationship of oxymatrine and voltage-gated potassium (Kv) channel in rat islet ß cells and INS-1 cells. MATERIALS AND METHODS: Insulin secretion and Kv channel currents were tested by radioimmunoassay and patch-clamp technique, respectively. The INS-1 cell viability was detected using cell counting kit-8 experiments. Flowcytometry analysis and western blot were employed for cell apoptosis and protein levels, respectively. INS-1 cell proliferation was assessed by the 5-Ethynyl-2'- deoxyuridine method. RESULTS: Oxymatrine potentiated insulin secretion at high glucose (P<0.01 vs 11.1 G, P<0.01 vs 16.7 G) and inhibited KV currents at 40 mV (45.73±15.34 pA/pF for oxymatrine, 73.80±19.23 pA/pF for control, P<0.05). After the INS-1 cells were treated with oxymatrine for 12 and 24 hr, KV2.1 channel protein was up-regulated (P<0.01 vs Control). At the same time, compared with the high glucose and high fat group, cell viability and proliferation ability were increased (P<0.01). The cell apoptotic rate was reduced, reaching 17.30%±1.00% at 12 hr and 10.35%±1.52% at 24 hr (P<0.01). These protective effects of oxymatrine were reversed by using Stromatoxin-1, a kv channel inhibitor. CONCLUSION: The results indicate that oxymatrine can stimulate insulin secretion and decrease kv channel currents in islet ß cells. Besides, oxymatrine also increases cell viability, proliferation, and reduces cell apoptosis in INS-1 cells. The effects of oxymatrine are related to kv channels. This finding provides new insight into the mechanisms of oxymatrine-regulated islet function.

Case Report: Tumor Microenvironment Characteristics in a Patient With HER2 Mutant Lung Squamous Cell Carcinoma Harboring High PD-L1 Expression Who Presented Hyperprogressive Disease.

BACKGROUND: High PD-L1 expression in non-small cell lung cancer (NSCLC) is evident to predict elevated immunotherapy efficacy, to which NSCLC with onco-driver gene mutations is probed with poor responsiveness. Thus, it is of great interest to investigate how effective immune monotherapy is in the presence of concurrent high PD-L1 expression and driving gene mutation. PATIENTS AND METHODS: We present a case of squamous lung cancer with high PD-L1 expression and HER2 exon 20 insertion (20Ins) who presented hyperprogressive disease (HPD) after being treated with PD-1 inhibitor. RESULTS: A 71-year-old female was diagnosed with advanced squamous lung cancer with 98% tumor proportion score of PD-1 and 20ins. She benefited from first-line docetaxel cisplatin followed by 2 months second-line afatinib. Third-line pembrolizumab monotherapy was then given. Unfortunately, she rapidly progressed with dramatically enlarged primary site as well as mediastinal lymph nodes and pleural effusion only 2 weeks later, presenting severe dyspnea and dysphagia. Re-biopsy was conducted, and we found that compared with the baseline, CD8+ T cells were largely recruited only in tumor stroma but not in tumor parenchyma. Tumor-associated macrophages were notably increased in both tumor stroma and parenchyma. Concomitantly, CD56dim NK cells in tumor parenchyma were decreased. CONCLUSIONS: Application of immune monotherapy in patients with positive driver genes demands extreme caution, even harboring high PD-L1 expression. Abnormality of tumor microenvironment might be critically involved in immune checkpoint inhibitor-induced HPD. Further study in greater depth is required.

Induction of ferroptosis-like cell death of eosinophils exerts synergistic effects with glucocorticoids in allergic airway inflammation.

INTRODUCTION: Eosinophils are critical in allergic disorders, and promoting eosinophil death effectively attenuates allergic airway inflammation. Ferroptosis is a recently described novel form of cell death; however, little is known about ferroptosis in eosinophils and related diseases. This study aimed to investigate the effects of ferroptosis-inducing agents (FINs) on eosinophil death and allergic airway inflammation, and to explore their potential synergistic effect with glucocorticoids (GCs). METHODS: Eosinophils isolated from the peripheral blood of humans or mice were incubated with FINs, and eosinophil ferroptosis was assessed. The in vivo effects of FINs alone or in combination with dexamethasone (DXMS) were examined in a mouse model of allergic airway inflammation. Bronchoalveolar lavage fluid and lung tissue were collected to examine airway inflammation. RESULTS: Treatment with FINs time and dose dependency induced cell death in human and mouse eosinophils. Interestingly, FINs induced non-canonical ferroptosis in eosinophils, which generated morphological characteristics unique to ferroptosis and was iron dependent but was independent of lipid peroxidation. The antioxidants glutathione and N-acetylcysteine significantly attenuated FIN-induced cell death. Treatment with FINs triggered eosinophil death in vivo and eventually relieved eosinophilic airway inflammation in mice. Furthermore, FINs exerted a synergistic effect with DXMS to induce eosinophil death in vitro and to alleviate allergic airway inflammation in vivo. CONCLUSIONS: FINs induced ferroptosis-like cell death of eosinophils, suggesting their use as a promising therapeutic strategy for eosinophilic airway inflammation, especially due to the advantage of their synergy with GCs in the treatment of allergic disorders.

Homeostatic and early-recruited CD101- eosinophils suppress endotoxin-induced acute lung injury.

INTRODUCTION: Acute lung injury (ALI) is a fatal but undertreated condition with severe neutrophilic inflammation, although little is known about the functions of eosinophils in the pathogenesis of ALI. Our objectives were to investigate the roles and molecular mechanisms of eosinophils in ALI. METHODS: Pulmonary eosinophils were identified by flow cytometry. Mice with abundant or deficient eosinophils were used. Cellularity of eosinophils and neutrophils in bronchoalveolar lavage fluid, inflammatory assessment, and survival rate were determined. Human samples were also used for validating experimental results. RESULTS: Blood eosinophils were increased in surviving patients with acute respiratory distress syndrome (ARDS) independent of corticosteroid usage. There existed homeostatic eosinophils in lung parenchyma in mice and these homeostatic eosinophils, originating from the bone marrow, were predominantly CD101-. More CD101- eosinophils could be recruited earlier than lipopolysaccharide (LPS)-initiated neutrophilic inflammation. Loss of eosinophils augmented LPS-induced pulmonary injury. Homeostatic CD101- eosinophils ameliorated, while allergic CD101+ eosinophils exacerbated, the neutrophilic inflammation induced by LPS. Likewise, CD101 expression in eosinophils from ARDS patients did not differ from healthy subjects. Mechanistically, CD101- eosinophils exhibited higher levels of Alox15 and Protectin D1. Administration of Protectin D1 isomer attenuated the neutrophilic inflammation. CONCLUSIONS: Collectively, our findings identify an uncovered function of native CD101- eosinophils in suppressing neutrophilic lung inflammation and suggest a potential therapeutic target for ALI.

Variation on the Microstructure and Mechanical Properties of Ti-Al-N Films Induced by RF-ICP Ion Source Enhanced Reactive Nitrogen Plasma Atmosphere.

Acquiring the optimum growth conditions of Ti-Al-N films, the effects of gas atmosphere, especially the reactive plasma on the material microstructures, and mechanical properties are still a fundamental and important issue. In this study, Ti-Al-N films are reactively deposited by radio frequency inductively coupled plasma ion source (RF-ICPIS) enhanced sputtering system. Different nitrogen gas flow rates in letting into the ion source are adopted to obtain nitrogen plasma densities and alter deposition atmosphere. It is found the nitrogen element contents in the films are quite influenced by the nitrogen plasma density, and the maximum value can reach as high as 67.8% at high gas flow circumstance. XRD spectra and FESEM images indicate that low plasma density is benefit for the film crystallization and dense microstructure. Moreover, the mechanical properties like hardness and tribological performance are mutually enhanced by adjusting the nitrogen atmosphere.

Author Correction: Eosinophil differentiation in the bone marrow is promoted by protein tyrosine phosphatase SHP2.

Since the publication of the article, the authors became aware that Figs. 1c, 5k and 6m contained errors in representative image and PAS score in control groups. The corrected Figs. 1c, 5k, and 6m are given below, and the figure legends are the same as original.

mTOR complexes differentially orchestrates eosinophil development in allergy.

Eosinophil infiltration is considered a hallmark in allergic airway inflammation, and the blockade of eosinophil differentiation may be an effective approach for treating eosinophil-related disorders. Mammalian target of rapamycin (mTOR) is a vital modulator in cell growth control and related diseases, and we have recently demonstrated that rapamycin can suppress eosinophil differentiation in allergic airway inflammation. Considering its critical role in haematopoiesis, we further investigated the role of mTOR in eosinophil differentiation in the context of asthmatic pathogenesis. Intriguingly, the inhibition of mTOR, either by genetic deletion or by another pharmacological inhibitor torin-1, accelerated the eosinophil development in the presence of IL-5. However, this was not observed to have any considerable effect on eosinophil apoptosis. The effect of mTOR in eosinophil differentiation was mediated by Erk signalling. Moreover, myeloid specific knockout of mTOR or Rheb further augmented allergic airway inflammation in mice after allergen exposure. Ablation of mTOR in myeloid cells also resulted in an increased number of eosinophil lineage-committed progenitors (Eops) in allergic mice. Collectively, our data uncovered the differential effects of mTOR in the regulation of eosinophil development, likely due to the distinct functions of mTOR complex 1 or 2, which thus exerts a pivotal implication in eosinophil-associated diseases.

Bcl-2 inhibitors reduce steroid-insensitive airway inflammation.

BACKGROUND: Asthmatic inflammation is dominated by accumulation of either eosinophils, neutrophils, or both in the airways. Disposal of these inflammatory cells is the key to disease control. Eosinophilic airway inflammation is responsive to corticosteroid treatment, whereas neutrophilic inflammation is resistant and increases the burden of global health care. Corticosteroid-resistant neutrophilic asthma remains mechanistically poorly understood and requires novel effective therapeutic strategies. OBJECTIVE: We sought to explore the underlying mechanisms of airway inflammation persistence, as well as corticosteroid resistance, and to investigate a new strategy of effective treatment against corticosteroid-insensitive neutrophilic asthma. METHODS: Mouse models of either eosinophil-dominated or neutrophil-dominated airway inflammation were used in this study to test corticosteroid sensitivity in vivo and in vitro. We also used vav-Bcl-2 transgenic mice to confirm the importance of granulocytes apoptosis in the clearance of airway inflammation. Finally, the Bcl-2 inhibitors ABT-737 or ABT-199 were tested for their therapeutic effects against eosinophilic or neutrophilic airway inflammation and airway hyperresponsiveness. RESULTS: Overexpression of Bcl-2 protein was found to be responsible for persistence of granulocytes in bronchoalveolar lavage fluid after allergic challenge. This was important because allergen-induced airway inflammation aggravated and persisted in vav-Bcl-2 transgenic mice, in which nucleated hematopoietic cells were overexpressed with Bcl-2 and resistant to apoptosis. The Bcl-2 inhibitors ABT-737 or ABT-199 play efficient roles in alleviation of either eosinophilic or corticosteroid-resistant neutrophilic airway inflammation by inducing apoptosis of immune cells, such as eosinophils, neutrophils, TH2 cells, TH17 cells, and dendritic cells. Moreover, these inhibitors were found to be more efficient than steroids to induce granulocyte apoptosis ex vivo from patients with severe asthma. CONCLUSION: Apoptosis of inflammatory cells is essential for clearance of allergen-induced airway inflammation. The Bcl-2 inhibitors ABT-737 or ABT-199 might be promising drugs for the treatment of airway inflammation, especially for corticosteroid-insensitive neutrophilic airway inflammation.

Role of macrophage colony-stimulating factor (M-CSF) in human granulosa cells.

Macrophage colony-stimulating factor (M-CSF) has been proved to have a positive role in the follicular development. We investigated its effect on human granulosa cells and found that M-CSF could stimulate the production of E2. The production of FSH receptors was enhanced by M-CSF in vitro in a dose-dependent manner with or without the addition of tamoxifen (p <0.05). Correspondingly, FSH was also able to coordinate the expression of M-CSF and its receptor (p <0.05). That maybe important to maintain the level of Nppc and the meiotic arrest of the oocyte. The protein p-JAK2 and p-STAT3 in JAK/STAT-signaling pathway elevated after the influence of M-CSF (p < 0.05). These results suggest that M-CSF has a role in regulating the response of granulosa cells to gonadotropins. Its function is associated with JAK/STAT-signaling pathway.

Ozone-induced IL-17A and neutrophilic airway inflammation is orchestrated by the caspase-1-IL-1 cascade.

Ozone is a common environmental air pollutant leading to respiratory illness. The mechanisms regulating ozone-induced airway inflammation remain poorly understood. We hypothesize that ozone-triggered inflammasome activation and interleukin (IL)-1 production regulate neutrophilic airway inflammation through IL-17A. Pulmonary neutrophilic inflammation was induced by extended (72 h) low-dose (0.7 ppm) exposure to ozone. IL-1 receptor 1 (Il1r1)(-/-), Il17a(-/-) mice and the caspase-1 inhibitor acetyl-YVAD-chloromethylketone (Ac-YVAD-cmk) were used for in vivo studies. Cellular inflammation and protein levels in bronchial alveolar lavage fluid (BALF), cytokines, and IL-17A-producing γδT-cells, as well as mitochondrial reactive oxygen species (ROS), mitochondrial DNA (mtDNA) release, and inflammasome activation in lung macrophages were analyzed. Ozone-induced neutrophilic airway inflammation, accompanied an increased production of IL-1ß, IL-18, IL-17A, Granulocyte-colony stimulating factor (G-CSF), Interferon-γ inducible protein 10 (IP-10) and BALF protein in the lung. Ozone-induced IL-17A production was predominantly in γδT-cells, and Il17a-knockout mice exhibited reduced airway inflammation. Lung macrophages from ozone-exposed mice exhibited higher levels of mitochondrial ROS, enhanced cytosolic mtDNA, increased caspase-1 activation, and higher production of IL-1ß. Il1r1-knockout mice or treatment with Ac-YVAD-cmk decreased the IL-17A production and subsequent airway inflammation. Taken together, we demonstrate that ozone-induced IL-17A and neutrophilic airway inflammation is orchestrated by the caspase-1-IL-1 cascade.

Rapamycin inhibition of eosinophil differentiation attenuates allergic airway inflammation in mice.

BACKGROUND AND OBJECTIVE: The mammalian target of rapamycin (mTOR) signalling pathway regulates immune responses, and promotes cell growth and differentiation. Inhibition of mTOR with rapamycin modulates allergic asthma, while the underlying molecular mechanisms remain elusive. Here, we demonstrate that rapamycin, effectively inhibits eosinophil differentiation, contributing to its overall protective role in allergic airway inflammation. METHODS: Rapamycin was administered in a mouse model of ovalbumin-induced allergic airway inflammation, and the eosinophil differentiation was analysed in vivo and in vitro. RESULTS: Rapamycin significantly attenuated allergic airway inflammation and markedly decreased the amount of eosinophils in local airways, peripheral blood and bone marrow, independently of levels of interleukin-5 (IL-5). In vitro colony forming unit assay and liquid culture demonstrated that rapamycin directly inhibited IL-5-induced eosinophil differentiation. In addition, rapamycin reduced the production of IL-6 and IL-13 by eosinophils. Rapamycin was also capable of reducing the eosinophil levels in IL-5 transgenic NJ.1638 mice, again regardless of the constitutive high levels of IL-5. Interestingly, rapamycin inhibition of eosinophil differentiation in turn resulted in an accumulation of eosinophil lineage-committed progenitors in bone marrow. CONCLUSIONS: Altogether these results clearly demonstrate a direct inhibitory role of rapamycin in eosinophil differentiation and function, and reemphasize the importance of rapamycin and possibly, mTOR, in allergic airway disease.

Tc17 cells are associated with cigarette smoke-induced lung inflammation and emphysema.

BACKGROUND AND OBJECTIVE: Some types of T lymphocytes, especially cytotoxic T-cells (Tc1) and T-helper (Th17) cells, play a pivotal role in cigarette smoke-induced lung diseases. However, whether Tc17 cells are involved remains largely unknown. We investigated Tc17 involvement using a cigarette smoke-exposure model. METHODS: Groups of mice were exposed to cigarette smoke or filtered air. At weeks 2, 8, 12 and 24, mice were sacrificed to observe histological changes by HE stain and/or immunohistochemical staining. The frequency of T cell subsets in the lung and spleen were detected by flow cytometry. In addition, the expression levels of T cell-related factors were measured by real-time polymerase chain reaction or enzyme-linked immunosorbent assay. RESULTS: Cigarette smoke caused substantial inflammatory cell infiltration and led to emphysema. Cigarette smoke exposure promoted the expression of interferon-gamma (IFN)-γ and interleukin (IL)-17A at the messenger ribonucleic acid and protein levels. In addition to Tc1 and Th17 cells, pulmonary and splenic Tc17 cells increased, which was accompanied by the upregulation of cytokines IL-6, transforming growth factor beta (TGF)-ß) and transcriptional factors Stat3 and RAR-related orphan receptor gamma. Compared with untreated mice, γH2AX-positive cells were more frequently observed in mice exposed to cigarette smoke. CONCLUSIONS: Long-term cigarette smoke exposure induced Tc17 cell expansion both locally and distally, which was associated with emphysema and deoxyribonucleic acid damage. As an important source of IL-17A, this T cell subset may be a potential target for chronic obstructive pulmonary disease therapy.

Exogenous interleukin-17A inhibits eosinophil differentiation and alleviates allergic airway inflammation.

IL-17 is known to play important roles in immune and inflammatory disease, such as in asthma, but its functions in allergic airway inflammation are still controversial, and the molecular mechanisms mediating these functions remain unclear. Increased production of eosinophils in bone marrow and their emergence in the airway have been linked to the onset and progression of allergic asthma. In this study, we investigated the effects of exogenous IL-17 on allergic airway inflammation and explored the underlying molecular mechanisms through eosinophil generation. Exogenous IL-17 significantly attenuated the features of allergic inflammation induced by ovalbumin in mice. It inhibited eosinophil differentiation both in vivo and in vitro, accompanied by down-regulated expression of CC chemokine receptor 3, GATA binding protein 1 (GATA-1), and GATA binding protein 2 (GATA-2), as well as reduced formation of common myeloid progenitors and eosinophil progenitors, but without influencing eosinophil apoptosis. IL-17 also significantly decreased the number of eosinophils in IL-5-transgenic mice, although it notably increased the levels of IL-3, IL-5, and granulocyte/macrophage colony-stimulating factor. In addition, IL-17 had little effect on secretion of the inflammatory cytokines by eosinophils. Neutralization of endogenous IL-17 significantly augmented eosinophil recruitment in the airways. Together, these findings suggest that exogenous IL-17 protects against allergic airway inflammation, most likely through inhibition of the eosinophil differentiation in bone marrow.