Number Of Neutrophils In Bronchoalveolar Lavage Fluid Research Articles

Alarmin-loaded extracellular lipid droplets induce airway neutrophil infiltration during type 2 inflammation

Group 2 innate lymphoid cells (ILC2s) play a crucial role in allergic diseases by coordinating a complex network of various effector cell lineages involved in type 2 inflammation. However, their function in regulating airway neutrophil infiltration, a deleterious symptom of severe asthma, remains unknown. Here, we observed ILC2-dependent neutrophil accumulation in the bronchoalveolar lavage fluid (BALF) of allergic mouse models. Chromatography followed by proteomics analysis identified the alarmin high mobility group box-1 (HMGB1) in the supernatant of lung ILC2s initiated neutrophil chemotaxis. Genetic perturbation of Hmgb1 in ILC2s reduced BALF neutrophil numbers and alleviated airway inflammation. HMGB1 was loaded onto the membrane of lipid droplets (LDs) released from activated lung ILC2s. Genetic inhibition of LD accumulation in ILC2s significantly decreased extracellular HMGB1 abundance and BALF neutrophil infiltration. These findings unveil a previously uncharacterized extracellular LD-mediated immune signaling delivery pathway by which ILC2s regulate airway neutrophil infiltration during allergic inflammation.

Inhibitory Effects of <italic>Ssanghwa-tang</italic> on Lung Injury and Muscle Loss in a Cigarette Smoke Extract and Lipopolysaccharide-induced Chronic Obstructive Pulmonary Disease Mouse Model

Objectives: This study evaluated the effects of <i>Ssanghwa-tang</i> (SHT) on lung injury and muscle loss in a COPD mouse model.Methods: C57BL/6 mice were challenged with cigarette smoke extract and lipopolysaccharide, and then treated with two concentrations of SHT (250 and 500 mg/kg). After sacrifice, the bronchoalveolar lavage fluid (BALF) or lung tissue was analyzed by cytospin, ELISA, real-time PCR, flow cytometry analysis, and H&E and Masson’s trichrome staining. The grip strength of COPD mice was measured using a grip strength meter. The running time of COPD mice was measured by a treadmill test. Muscle tissue of the quadriceps was stained with H&E and Masson’s trichrome staining.Results: SHT significantly inhibited the increase in neutrophil numbers in BALF and significantly decreased immune cell activity in BALF and lung tissue. It also significantly inhibited the increase in TNF-α, IL-17, and MIP2 in BALF. Real-time PCR analysis revealed that the mRNA expression of TNF-α, IL-17, MIP2, and TRPV1 in lung tissue showed a significant decrease compared with the control group. Lung tissue damage was significantly reduced in the histological analysis. The grip strength and running time of the COPD mice showed a significant decrease compared with the control group. In histological staining, SHT was found to reduce the damage to muscle tissue.Conclusions: This study indicates that SHT can be used as a therapeutic agent for COPD patients by inhibiting lung injury and muscle loss.

The effect of bradykinin 1 receptor antagonist BI 1026706 on pulmonary inflammation after segmental lipopolysaccharide challenge in healthy smokers

BackgroundBradykinin 1 receptor (B1R) signalling pathways may be involved in the inflammatory pathophysiology of chronic obstructive pulmonary disease (COPD). B1R signalling is induced by inflammatory stimuli or tissue injury and leads to activation and increased migration of pro-inflammatory cells. Lipopolysaccharide (LPS) lung challenge in man is an experimental method of exploring inflammation in the lung whereby interference in these pathways can help to assess pharmacologic interventions in COPD. BI 1026706, a potent B1R antagonist, was hypothesized to reduce the inflammatory activity after segmental lipopolysaccharide (LPS) challenge in humans due to decreased pulmonary cell influx. MethodsIn a monocentric, randomized, double-blind, placebo-controlled, parallel-group, phase I trial, 57 healthy, smoking subjects were treated for 28 days with either oral BI 1026706 100 mg bid or placebo. At day 21, turbo-inversion recovery magnitude magnetic resonance imaging (TIRM MRI) was performed. On the last day of treatment, pre-challenge bronchoalveolar lavage fluid (BAL) and biopsies were sampled, followed by segmental LPS challenge (40 endotoxin units/kg body weight) and saline control instillation in different lung lobes. Twenty-four hours later, TIRM MRI was performed, then BAL and biopsies were collected from the challenged segments. In BAL samples, cells were differentiated for neutrophil numbers as the primary endpoint. Other endpoints included assessment of safety, biomarkers in BAL (e.g. interleukin-8 [IL-8], albumin and total protein), B1R expression in lung biopsies and TIRM score by MRI as a measure for the extent of pulmonary oedema. ResultsAfter LPS, but not after saline, high numbers of inflammatory cells, predominantly neutrophils were observed in the airways. IL-8, albumin and total protein were also increased in BAL samples after LPS challenge as compared with saline control. There were no significant differences in cells or other biomarkers from BAL in volunteers treated with BI 1026706 compared with those treated with placebo. Unexpectedly, neutrophil numbers in BAL were 30% higher and MRI-derived extent of oedema was significantly higher with BI 1026706 treatment compared with placebo, 24 h after LPS challenge. Adverse events were mainly mild to moderate and not different between treatment groups. ConclusionsTreatment with BI 1026706 for four weeks was safe and well-tolerated in healthy smoking subjects. BI 1026706 100 mg bid did not provide evidence for anti-inflammatory effects in the human bronchial LPS challenge model. Trial registrationThe study was registered on January 14, 2016 at ClinicalTrials.gov (NCT02657408).

Rosavin inhibits neutrophil extracellular traps formation to ameliorate sepsis-induced lung injury by regulating the MAPK pathway.

Sepsis is a systemic organ dysfunction caused by infection, and the most affected organ is the lungs. Rosavin, a traditional Tibetan medicine, exerts an impressive anti--inflammatory effect. However, its effects on sepsis-related lung damage have not been investigated. This study aimed to investigate the effects of Rosavin on cecal ligation and puncture (CLP)-induced lung injury. The sepsis mouse model was established by CLP, and the mice were pretreated with Rosavin to explore whether it contributed to the alleviation of lung injury. Hematoxylin-eosin (H&E) stain and lung injury score were used to assess the severity of lung injury. The bronchoalveolar lavage fluid (BALF) inflammatory mediators (tumor necrosis factor-α [TNF-α], interleukin-6 [IL-6], IL-1β, and IL-17A) were detected by ELISA. The number of neutrophils in BALF was detected using flow cytometry. The immunofluorescence assay was used to detect histone and myeloperoxidase (MPO) in lung tissues. Then, the western blot was performed to detect the expression of mitogen-activated protein kinase (MAPK) pathways (extracellular regulated kinase [ERK], p-ERK, p38, p-p38, Jun N-terminal kinase 1/2 [JNK1/2], and p-JNK1/2) in lung tissues. We found that Rosavin significantly attenuated sepsis-induced lung injury. Specifically, Rosavin significantly inhibited inflammation response by decreasing the secretion of inflammatory mediators. The level of neutrophil extracellular traps (NETs) and MPO activity in CLP were decreased after administration with Rosavin. Moreover, the western blot showed that Rosavin could suppress NETs formation by inhibiting the MAPK/ERK/p38/JNK signaling pathway. These findings demonstrated that Rosavin inhibited NETs formation to attenuate sepsis-induced lung injury, and the inhibitory effect may be exerted via deregulation of the MAPK pathways.

The effect of mitochondria-targeted slow hydrogen sulfide releasing donor AP39-treatment on airway inflammation

Mitochondrial dysfunction has been shown to contribute to the pathophysiology of airway diseases. Therefore, mitochondria are targeted in the development of new therapeutic approaches. Hydrogen sulfide (H2S) has been shown to be involved in the pathophysiological processes of airway inflammation. We aimed to evaluate the effect of mitochondria-targeted slow H2S releasing donor AP39 [(10-oxo-10-(4-(3-thioxo-3H-1,2-dithiol5yl)phenoxy)decyl)triphenylphosphoniumbromide)] on lipopolysaccharide (LPS)-induced airway inflammation in mice. LPS was applied to female Balb/c mice by intranasal (i.n.) route to induce airway inflammation and the subgroups of mice were treated with i.n. AP39 (250–1000 nmol/kg). 48 h after LPS administration airway reactivity was evaluated in vivo, then bronchoalveolar lavage (BAL) fluid and lungs were collected. LPS application led to bronchial hyperreactivity and neutrophil infiltration into the lung tissues along with increased TNF-α, IL-1β and IL-6 levels in BAL fluid. LPS also induced an increase in the rate of glycolysis, glycogenolysis and Krebs-cycle. AP39 treatment prevented the LPS-induced bronchial hyperreactivity and reversed the increase in TNF-α and IL-6 levels in BAL fluid. The increase in neutrophil numbers in BAL fluid was also prevented by AP39 treatment at the highest dose. Our results indicate that AP39 can prevent bronchial hyperreactivity and decrease airway inflammation. Targeting H2S to the mitochondria may be a new therapeutic approach in airway inflammation.

Release of extracellular superoxide dismutase into alveolar fluid protects against acute lung injury and inflammation in Staphylococcus aureus pneumonia.

Acute respiratory distress syndrome (ARDS) remains a significant cause of morbidity and mortality in critically ill patients. Oxidative stress and inflammation play a crucial role in the pathogenesis of ARDS. Extracellular superoxide dismutase (EC-SOD) is abundant in the lung and is an important enzymatic defense against superoxide. Human single-nucleotide polymorphism in matrix binding region of EC-SOD leads to the substitution of arginine to glycine at position 213 (R213G) and results in release of EC-SOD into alveolar fluid, without affecting enzyme activity. We hypothesized that R213G EC-SOD variant protects against lung injury and inflammation via the blockade of neutrophil recruitment in infectious model of methicillin-resistant S. aureus (MRSA) pneumonia. After inoculation with MRSA, wild-type (WT) mice had impaired integrity of alveolar-capillary barrier and increased levels of IL-1β, IL-6, and TNF-α in the broncho-alveolar lavage fluid (BALF), while infected mice expressing R213G EC-SOD variant maintained the integrity of alveolar-capillary interface and had attenuated levels of proinflammatory cytokines. MRSA-infected mice expressing R213G EC-SOD variant also had attenuated neutrophil numbers in BALF and decreased expression of neutrophil chemoattractant CXCL1 by the alveolar epithelial ATII cells, compared with the infected WT group. The decreased neutrophil numbers in R213G mice were not due to increased rate of apoptosis. Mice expressing R213G variant had a differential effect on neutrophil functionality-the generation of neutrophil extracellular traps (NETs) but not myeloperoxidase (MPO) levels were attenuated in comparison with WT controls. Despite having the same bacterial load in the lung as WT controls, mice expressing R213G EC-SOD variant were protected from extrapulmonary dissemination of bacteria.

Gastrointestinal consequences of lipopolysaccharide-induced lung inflammation

BackgroundRespiratory inflammation is the body’s response to lung infection, trauma or hypersensitivity and is often accompanied by comorbidities, including gastrointestinal (GI) symptoms. Why respiratory inflammation is accompanied by GI dysfunction remains unclear. Here, we investigate the effect of lipopolysaccharide (LPS)-induced lung inflammation on intestinal barrier integrity, tight-junctions, enteric neurons and inflammatory marker expression.MethodsFemale C57bl/6 mice (6–8 weeks) were intratracheally administered LPS (5 µg) or sterile saline, and assessed after either 24 or 72 h. Total and differential cell counts in bronchoalveolar lavage fluid (BALF) were used to evaluate lung inflammation. Intestinal barrier integrity was assessed via cross sectional immunohistochemistry of tight junction markers claudin-1, claudin-4 and EpCAM. Changes in the enteric nervous system (ENS) and inflammation in the intestine were quantified immunohistochemically using neuronal markers Hu + and nNOS, glial markers GFAP and S100β and pan leukocyte marker CD45.ResultsIntratracheal LPS significantly increased the number of neutrophils in BALF at 24 and 72 h. These changes were associated with an increase in CD45 + cells in the ileal mucosa at 24 and 72 h, increased goblet cell expression at 24 h, and increased expression of EpCAM at 72 h. LPS had no effect on the expression of GFAP, S100β, nor the number of Hu + neurons or proportion of nNOS neurons in the myenteric plexus.ConclusionsIntratracheal LPS administration induces inflammation in the ileum that is associated with enhanced expression of EpCAM, decreased claudin-4 expression and increased goblet cell density, these changes may contribute to systemic inflammation that is known to accompany many inflammatory diseases of the lung.

Human placental hematopoietic stem cell derived natural killer cells (CYNK-001) mediate protection against influenza a viral infection

ABSTRACT Influenza A virus (IAV) infections are associated with a high healthcare burden around the world and there is an urgent need to develop more effective therapies. Natural killer (NK) cells have been shown to play a pivotal role in reducing IAV-induced pulmonary infections in preclinical models; however, little is known about the therapeutic potential of adoptively transferred NK cells for IAV infections. Here, we investigated the effects of CYNK-001, human placental hematopoietic stem cell derived NK cells that exhibited strong cytolytic activity against a range of malignant cells and expressed high levels of activating receptors, against IAV infections. In a severe IAV-induced acute lung injury model, mice treated with CYNK-001 showed a milder body weight loss and clinical symptoms, which led to a delayed onset of mortality, thus demonstrating their antiviral protection in vivo. Analysis of bronchoalveolar lavage fluid (BALF) revealed that CYNK-001 reduced proinflammatory cytokines and chemokines highlighting CYNK-001’s anti-inflammatory actions in viral induced-lung injury. Furthermore, CYNK-001-treated mice had altered immune responses to IAV with reduced number of neutrophils in BALF yet increased number of CD8+ T cells in the BALF and lung compared to vehicle-treated mice. Our results demonstrate that CYNK-001 displays protective functions against IAV via its anti-inflammatory and immunomodulating activities, which leads to alleviation of disease burden and progression in a severe IAV-infected mice model. The potential of adoptive NK therapy for IAV infections warrants clinical investigation.

Interventional effect of IL-17A on chronic obstructive pulmonary disease and its mechanism

Objective: To investigate the intervention effects and mechanism of interleukin-17A (IL-17A) on chronic obstructive pulmonary disease (COPD). Methods: C57BL/6 mice were randomly divided into wild type blank control group, wild type COPD group and IL-7A knockout COPD group. Mice in wild type blank control group received no treatment, and mice in the other two groups were exposed to cigarette smoke to induce COPD (Cigarette: 1 cigarette / time, 4 times/day, 45 minutes/time; interval time: 1 hour; total intervention time: 90 days). Lung function of mice was assessed using animal pulmonary function machine. Bronchoalveolar lavage fluid (BALF) of mice was collected and BALF cell count and classification were determined. The lung tissue of mice was collected, the expression level of IL-17A in airway epithelium was determined by flow cytometry, and the levels of inflammatory factors in lung tissue were determined by enzyme-linked immunosorbent assay. The expression level of JNK/AP1 signaling pathway protein in mouse lung tissue was determined by Western blot. Results: Compared with the wild type blank control group mice, the wild type COPD group mice had significantly higher expression level of IL-17A, significantly lower peak inspiratory flow rate (PIF) and peak expiratory flow rate (PEF), significantly higher number of BALF neutrophils, eosinophils, lymphocytes and macrophage, significantly higher expression levels of CXC chemokine 1(CXCL1), CXC chemokine 2 (CXCL2), interleukin-1β (IL-1β) and interleukin-6 (IL-6), and significantly higher phosphorylation level of JNK, cJun and cFos and AP1 expression levels (P＜0.05). Compared with COPD mice, IL-17A expression level in airway epithelium of mice in IL-7A knockout COPD group was significantly lower, PIF and PEF were higher, the number of BALF neutrophils, eosinophils, lymphocytes and macrophage was significantly lower, the expression levels of CXCL1, CXCL2, IL-1β and IL-6 in lung tissue were lower, and the phosphorylation levels of JNK, cJun and cFos and AP1 expression levels were significantly lower (P＜0.05). Conclusion: Cigarette smoke can induce the production of IL-17A and reduce (or inhibit) the production (or expression or secretion) of IL-17A in mouse airway epithelium, thus inhibiting the JNK/AP1 signaling pathway to reduce the airway inflammation and improve the lung function of COPD mice.

Susceptibility Analysis in Several Mouse Strains Reveals Robust T-Cell Responses After Mycoplasma pneumoniae Infection in DBA/2 Mice.

Mycoplasma pneumoniae (Mp) is a highly contagious respiratory pathogen responsible for human community-acquired pneumonia. The number of antibiotic-resistant Mp strains is increasing; therefore, to develop novel therapeutics, it is crucial to precisely understand the pathogenesis of mycoplasma pneumonia. Herein, we examined the susceptibility and response to Mp among eight inbred mouse strains. Following infection, the bacterial load in the bronchoalveolar lavage fluid (BALF) from DBA/2 mice was higher than that in the other tested strains such as BALB/c mice, which are frequently used in Mp research. In contrast, the numbers of CD45+ immune cells and neutrophils in BALF were comparable between BALB/c and DBA/2 mice, with lower numbers observed in C57BL/6J and CBA/N mice than in BALB/c mice. Among the tested strains, the BALF level of interleukin 12 subunit p40 was highest in DBA/2 mice; however, significant differences in other cytokines levels were not observed between BALB/c and DBA/2 mice. After Mp infection, Mp-specific Th1 and Th17 responses were significantly enhanced in DBA/2 mice when compared with BALB/c mice. Furthermore, prior infection with Mp increased the number of neutrophils in BALF after the reinfection of DBA/2 mice through an Mp-specific CD4+ T cell-dependent mechanism. Thus, DBA/2 may be an appropriate strain for evaluating Mp infection. Moreover, a comparison of responses revealed by various inbred mouse strains could be useful for elucidating the pathogenesis of Mycoplasma pneumonia.

The pulmonary toxicity of carboxylated or aminated multi-walled carbon nanotubes in mice is determined by the prior purification method

BackgroundInhalation of multi-walled carbon nanotubes (MWCNTs) poses a potential risk to human health. In order to safeguard workers and consumers, the toxic properties of MWCNTs need to be identified. Functionalization has been shown to either decrease or increase MWCNT-related pulmonary injury, depending on the type of modification. We, therefore, investigated both acute and chronic pulmonary toxicity of a library of MWCNTs derived from a common pristine parent compound (NC7000).MethodsMWCNTs were thermally or chemically purified and subsequently surface functionalized by carboxylation or amination. To evaluate pulmonary toxicity, male C57BL6 mice were dosed via oropharyngeal aspiration with either 1.6 or 4 mg/kg of each MWCNT type. Mitsui-7 MWCNT was used as a positive control. Necropsy was performed at days 3 and 60 post-exposure to collect bronchoalveolar lavage fluid (BALF) and lungs.ResultsAt day 3 all MWCNTs increased the number of neutrophils in BALF. Chemical purification had a greater effect on pro-inflammatory cytokines (IL-1β, IL-6, CXCL1) in BALF, while thermal purification had a greater effect on pro-fibrotic cytokines (CCL2, OPN, TGF-β1). At day 60, thermally purified, carboxylated MWCNTs had the strongest effect on lymphocyte numbers in BALF. Thermally purified MWCNTs caused the greatest increase in LDH and total protein in BALF. Furthermore, the thermally purified and carboxyl- or amine-functionalized MWCNTs caused the greatest number of granulomatous lesions in the lungs. The physicochemical characteristics mainly associated with increased toxicity of the thermally purified derivatives were decreased surface defects and decreased amorphous content as indicated by Raman spectroscopy.ConclusionsThese data demonstrate that the purification method is an important determinant of lung toxicity induced by carboxyl- and amine-functionalized MWCNTs.

Alveolar Epithelial Cells Promote IGF-1 Production by Alveolar Macrophages Through TGF-β to Suppress Endogenous Inflammatory Signals.

To maintain alveolar gas exchange, the alveolar surface has to limit unnecessary inflammatory responses. This involves crosstalk between alveolar epithelial cells (AECs) and alveolar macrophages (AMs) in response to damaging factors. We recently showed that insulin-like growth factor (IGF)-1 regulates the phagocytosis of AECs. AMs secrete IGF-1 into the bronchoalveolar lavage fluid (BALF) in response to inflammatory stimuli. However, whether AECs regulate the production of IGF-1 by AMs in response to inflammatory signals remains unclear, as well as the role of IGF-1 in controlling the alveolar balance in the crosstalk between AMs and AECs under inflammatory conditions. In this study, we demonstrated that IGF-1 was upregulated in BALF and lung tissues of acute lung injury (ALI) mice, and that the increased IGF-1 was mainly derived from AMs. In vitro experiments showed that the production and secretion of IGF-1 by AMs as well as the expression of TGF-β were increased in LPS-stimulated AEC-conditioned medium (AEC-CM). Pharmacological blocking of TGF-β in AECs and addition of TGF-β neutralizing antibody to AEC-CM suggested that this AEC-derived cytokine mediates the increased production and secretion of IGF-1 from AMs. Blocking TGF-β synthesis or treatment with TGF-β neutralizing antibody attenuated the increase of IGF-1 in BALF in ALI mice. TGF-β induced the production of IGF-1 by AMs through the PI3K/Akt signaling pathway. IGF-1 prevented LPS-induced p38 MAPK activation and the expression of the inflammatory factors MCP-1, TNF-α, and IL-1β in AECs. However, IGF-1 upregulated PPARγ to increase the phagocytosis of apoptotic cells by AECs. Intratracheal instillation of IGF-1 decreased the number of polymorphonuclear neutrophils in BALF of ALI model mice, reduced alveolar congestion and edema, and suppressed inflammatory cell infiltration in lung tissues. These results elucidated a mechanism by which AECs used TGF-β to regulate IGF-1 production from AMs to attenuate endogenous inflammatory signals during alveolar inflammation.

Role of Nrf2 in inflammatory response in lung of mice exposed to zinc oxide nanoparticles

BackgroundZinc oxide nanoparticles (ZnO-NPs) are widely used in many industrial sectors and previous studies have reported that exposure of the lungs to ZnO-NPs induces both acute and/or chronic pulmonary inflammation, but the exact mechanism underlying such response remains elusive. This study investigated the role of nuclear factor-erythroid 2-related factor (Nrf2) in pulmonary inflammation induced by exposure to ZnO-NPs using Nrf2 null (Nrf2−/−) mice.MethodsTwenty-four male Nrf2−/− mice and thirty male wild type C57BL/6 J mice were divided into three groups of eight and ten each respectively, and exposed once to ZnO-NPs at 0, 10, 30 μg/mouse by pharyngeal aspiration. At 14 days after the exposure to ZnO-NPs, bronchoalveolar lavage fluid (BALF) and lungs were collected to quantify protein level and the number of inflammatory cells. The mRNA levels of Nrf2-dependent antioxidant enzymes and inflammatory cytokines in lung tissue were measured.ResultsExposure to ZnO-NPs dose-dependently increased the number of total cells, macrophages, lymphocytes and eosinophils in BALF both in Nrf2−/− mice and wild type mice, but the magnitude of increase was significantly higher in Nrf2−/− mice than wild type mice. The number of neutrophils in BALF increased in Nrf2−/− mice, being accompanied by marginal trend of increase in mRNA expression of MIP-2, neutrophil chemoattractant, but such changes were not observed in wild type mice. Exposure to ZnO-NPs did not dose-dependently increase mRNA level of Nrf2-dependent antioxidant enzymes both in Nrf2−/− mice and wild type mice.ConclusionPharyngeal aspiration of ZnO-NPs induced infiltration of inflammatory cells in the lung of mice, but minimally induced Nrf2-dependent antioxidant enzymes. The results suggest that Nrf2 play a role in negative regulation on ZnO-NP exposure-induced neutrophil migration, but does not demonstrate that the regulation is through suppression of oxidative stress.

Isoflavone Aglycones Attenuate Cigarette Smoke-Induced Emphysema via Suppression of Neutrophilic Inflammation in a COPD Murine Model.

Chronic obstructive pulmonary disease (COPD), a lung disease caused by chronic exposure to cigarette smoke, increases the number of inflammatory cells such as macrophages and neutrophils and emphysema. Isoflavone is a polyphenolic compound that exists in soybeans. Daidzein and genistein, two types of isoflavones, have been reported to have anti-inflammatory effects in various organs. We hypothesized that the daidzein-rich soy isoflavone aglycones (DRIAs) attenuate cigarette smoke-induced emphysema in mice. Mice were divided into four groups: the (i) control group, (ii) isoflavone group, (iii) smoking group, and (iv) isoflavone + smoking group. The number of inflammatory cells in the bronchoalveolar lavage fluid (BALF) and the airspace enlargement using the mean linear intercept (MLI) were determined 12 weeks after smoking exposure. Expressions of neutrophilic inflammatory cytokines and chemokines were also examined. In the isoflavone + smoking group, the number of neutrophils in BALF and MLI was significantly less than that in the smoking group. Furthermore, the gene-expressions of TNF-α and CXCL2 (MIP-2) in the isoflavone + smoking group were significantly less than those in the smoking group. Supplementation of the COPD murine model with DRIAs significantly attenuates pathological changes of COPD via suppression of neutrophilic inflammation.

Investigation of blood biomarkers for the diagnosis of mild to moderate asthma in horses.

BackgroundAsthma in horses is associated with nonspecific respiratory clinical signs and may be manifested only as exercise intolerance. Its diagnosis relies on bronchoalveolar lavage fluid (BALF) cytology in the presence of compatible clinical signs. The identification of blood biomarkers for this condition would facilitate diagnosis in the field, because there are regional areas where BAL is not routinely performed in clinical practice.ObjectiveIdentification of blood biomarkers for the diagnosis of asthma in horses.AnimalsFourteen horses with asthma with increased neutrophil numbers in BALF (neutrophilic asthma), 9 healthy control horses, and 10 horses with other pathologic conditions (pathologic controls).MethodsPhysical examination, clinical score, hematology, and BALF cytology (in a subset of horses) were performed. Serum concentrations of surfactant protein D (SP‐D), haptoglobin, and secretoglobin (SCGB) were measured using commercial ELISA assays.ResultsSerum concentration of SP‐D > 43 ng/mL, serum concentration of haptoglobin >5730 ng/mL, and serum concentration of SCGB <19 ng/mL allowed differentiation of horses with neutrophilic asthma from horses of the control groups (healthy and pathologic) with sensitivity of 55, 95, and 75%, and specificity of 67, 28, and 60%, respectively. Specificity of 100% and sensitivity of 45% were obtained with the combination of SP‐D, haptoglobin, and SCGB at the serum concentrations indicated above. Specificity of 95% and sensitivity of 45% were obtained with the combination of SP‐D and SCGB serum concentrations.Conclusions and Clinical ImportanceHaptoglobin, SCGB, and SP‐D may be diagnostic aids in horses with clinical signs of lower airway disease and neutrophilic pulmonary inflammation.

Effects of Zinc Finger Protein A20 on Lipopolysaccharide (LPS)-Induced Pulmonary Inflammation/Anti-Inflammatory Mediators in an Acute Lung Injury/Acute Respiratory Distress Syndrome Rat Model

BackgroundThe aim of this study was to investigate the effects of zinc finger protein A20 on lipopolysaccharide (LPS)-induced pulmonary inflammation/anti-inflammatory mediators in an acute lung injury/acute respiratory distress syndrome (ALI/ARDS) rat model.Material/MethodsForty-eight ALI/ARDS rats were selected and assigned into normal saline (NS) (injected with NS), LPS (injected with LPS), LPS-C1 (injected with pEGFP-C1, NS and LPS), and A20 groups (injected with pEGFP-C1-A20, NS, and LPS). The wet/dry (W/D) ratio of rat lung tissues and total protein concentration and the number of neutrophils in bronchoalveolar lavage fluid (BALF) were detected. Enzyme-linked immunosorbent assay (ELISA) and qRT-PCR were applied to detect the protein and mRNA expressions of A20, IL-10, and TNF-α, respectively. Western blotting was employed to detect the protein expressions of A20, nuclear factor-kappa B (NF-κB) p65 and NF-κB p-P65 in rat lung tissues.ResultsCompared with the NS group, the W/D ratio of rat lung tissues and total protein concentration and the number of neutrophils in BALF in the other 3 groups increased significantly. The protein and mRNA expressions of A20, IL-10, and TNF-α were significantly higher in the LPS group than in the NS group. The protein and mRNA expressions of A20 and IL-10 were significantly up-regulated and the expression of TNF-α, NF-κB p65, and NF-κB p-P65 was significantly down-regulated in rats injected with A20 compared to those in the LPS group.ConclusionsThe study provided evidence that zinc finger protein A20 can alleviate pulmonary inflammation by inhibiting TNF-α, NF-κB p65, and NF-κB p-P65 expressions and promoting IL-10 expression.

Comparison of pulmonary inflammatory responses following intratracheal instillation and inhalation of nanoparticles

In order to examine whether intratracheal instillation studies can be useful for determining the harmful effect of nanoparticles, we performed inhalation and intratracheal instillation studies using samples of the same nanoparticles. Nickel oxide nanoparticles (NiO) and titanium dioxide nanoparticles (TiO2) were used as chemicals with high and low toxicities, respectively. In the intratracheal instillation study, rats were exposed to 0.2 or 1 mg of NiO or TiO2. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed from 3 days to 6 months following the single intratracheal instillation. In the inhalation study, rats were exposed to inhaled NiO or TiO2 (1.65, 1.84 mg/m3, respectively) for 4 weeks. The same endpoints were examined from 3 days to 3 months after the end of exposure. Inhalation of NiO induced an increase in the number of neutrophils in BALF and concentrations of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2 and heme oxygenase (HO)-1. Intratracheal instillation of NiO induced persistent inflammation and upregulation of these cytokines was observed in the rats. However, inhalation of TiO2 did not induce pulmonary inflammation, and intratracheal instillation of TiO2 transiently induced an increase in the number of neutrophils in BALF and the concentrations of CINC-1, CINC-2 and HO-1. Taken together, a difference in pulmonary inflammation was observed between the high and low toxicity nanomaterials in the intratracheal instillation studies, as in the inhalation studies, suggesting that intratracheal instillation studies may be useful for ranking the harmful effects of nanoparticles.

Pulmonary toxicity of well-dispersed cerium oxide nanoparticles following intratracheal instillation and inhalation.

We performed inhalation and intratracheal instillation studies of cerium dioxide (CeO2) nanoparticles in order to investigate their pulmonary toxicity, and observed pulmonary inflammation not only in the acute and but also in the chronic phases. In the intratracheal instillation study, F344 rats were exposed to 0.2 mg or 1 mg of CeO2 nanoparticles. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed from 3 days to 6 months following the instillation. In the inhalation study, rats were exposed to the maximum concentration of inhaled CeO2 nanoparticles (2, 10 mg/m3, respectively) for 4 weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were examined from 3 days to 3 months after the end of the exposure. The intratracheal instillation of CeO2 nanoparticles caused a persistent increase in the total and neutrophil number in BALF and in the concentration of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in BALF during the observation time. The inhalation of CeO2 nanoparticles also induced a persistent influx of neutrophils and expression of CINC-1, CINC-2, and HO-1 in BALF. Pathological features revealed that inflammatory cells, including macrophages and neutrophils, invaded the alveolar space in both studies. Taken together, the CeO2 nanoparticles induced not only acute but also chronic inflammation in the lung, suggesting that CeO2 nanoparticles have a pulmonary toxicity that can lead to irreversible lesions.

House Dust Mite Allergen Regulates Constitutive Apoptosis of Normal and Asthmatic Neutrophils via Toll-Like Receptor 4.

House dust mites (HDMs) induce allergic diseases such as asthma. Neutrophil apoptosis is an important process of innate immunity, and its dysregulation is associated with asthma. In this study, we examined the effects of HDM on constitutive apoptosis of normal and asthmatic neutrophils. Extract of Dermatophagoides pteronissinus (DP) inhibited neutrophil apoptosis, but Dermatophagoides farinae extract had no effect. Anti-apoptotic signaling mediated by DP involves in TLR4, Lyn, PI3K, Akt, ERK, and NF-κB in normal neutrophils. DP delayed cleavage of procaspase 9 and procaspase 3 and the decrease in Mcl-1 expression. Supernatant collected from DP-treated normal neutrophils inhibited the constitutive apoptosis of normal neutrophils, and S100A8 and S100A9 were identified as anti-apoptotic proteins in the supernatant. S100A8 and S100A9 transduced the anti-apoptotic signal via TLR4, Lyn, PI3K, Akt, ERK, and NF-κB. DP also suppressed asthmatic neutrophil apoptosis and induced secretion of S100A8 and S100A9, which delayed the constitutive apoptosis. The anti-apoptotic effects of DP, S100A8 and S100A9 in asthmatic neutrophils are associated with TLR4, Lyn, PI3K, Akt, ERK, and NF-κB. The concentrations of S100A8 and S100A9 were significantly elevated in asthmatic bronchoalveolar lavage fluid (BALF) when compared to normal BALF (p<0.01), but not in serum. S100A8 concentration in BALF was positively correlated with the number of BALF neutrophils and negatively correlated with FEV1(%). These findings improve our understanding of the role of HDM in regulation of neutrophil apoptosis in normal individuals and asthmatics and will enable elucidation of asthma pathogenesis.

Genetic Deletion and Pharmacological Inhibition of PI3K γ Reduces Neutrophilic Airway Inflammation and Lung Damage in Mice with Cystic Fibrosis-Like Lung Disease.

Purpose. Neutrophil-dominated airway inflammation is a key feature of progressive lung damage in cystic fibrosis (CF). Thus, reducing airway inflammation is a major goal to prevent lung damage in CF. However, current anti-inflammatory drugs have shown several limits. PI3Kγ plays a pivotal role in leukocyte recruitment and activation; in the present study we determined the effects of genetic deletion and pharmacologic inhibition of PI3Kγ on airway inflammation and structural lung damage in a mouse model of CF lung disease. Methods. βENaC overexpressing mice (βENaC-Tg) were backcrossed with PI3Kγ-deficient (PI3Kγ KO) mice. Tissue damage was assessed by histology and morphometry and inflammatory cell number was evaluated in bronchoalveolar lavage fluid (BALF). Furthermore, we assessed the effect of a specific PI3Kγ inhibitor (AS-605240) on inflammatory cell number in BALF. Results. Genetic deletion of PI3Kγ decreased neutrophil numbers in BALF of PI3Kγ KO/βENaC-Tg mice, and this was associated with reduced emphysematous changes. Treatment with the PI3Kγ inhibitor AS-605240 decreased the number of neutrophils in BALF of βENaC-Tg mice, reproducing the effect observed with genetic deletion of the enzyme. Conclusions. These results demonstrate the biological efficacy of both genetic deletion and pharmacological inhibition of PI3Kγ in reducing chronic neutrophilic inflammation in CF-like lung disease in vivo.