Effect of formoterol and budesonide on chemokine release, chemokine receptor expression and chemotaxis in human neutrophils

Intratracheal instillation of budesonide suspension versus normal saline on oxidative stress in neonates with meconium aspiration syndrome

BACKGROUND

Presently, the efficacy of neonatal resuscitation techniques via interventions such as oral, nasal, and endotracheal suction for preventing meconium aspiration syndrome (MAS) after delivery has not been satisfactory.

OBJECTIVE

This study aimed to investigate the role of intratracheal instillation of budesonide on oxidative stress in MAS.

METHODS

Sixty-two neonates with MAS admitted to Huai'an Maternity and Child Healthcare Hospital from January 2018 to June 2020 were divided into a study group (intratracheal instillation of 2 ml budesonide suspension; n = 31) and a control group (intratracheal instillation of 2 ml normal saline; n = 31). Collect data from two groups of patients and evaluate clinical outcomes, including oxygenation index (OI), as well as serum total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI) and 8-Isoprostane before treatment and 72h after admission.

RESULTS

We found no statistical differences in mortality, complication rate, total oxygen inhalation time, OI before treatment and 72h after admission between the two groups of neonates with MAS, while the duration of invasive respiratory support in the study group was significantly shorter than in the control group. Also, serum TAC, TOS, OSI and 8-isoprostane levels were not statistically different before treatment between the two groups. After 72h of admission, OSI and 8-Isoprostane in neonates with MAS in the study group were much lower than those in the control group. TOS, OSI, 8-Isoprostane in the control group and 8-Isoprostane in the study group were significantly higher than those before treatment. As for TAC and TOS, no significant differences were observed between the two groups.

CONCLUSION

Intratracheal instillation of budesonide was shown to alleviate oxidative stress and shorten invasive ventilation time in neonates with MAS.

The PDE4 Inhibitor Tanimilast Restrains the Tissue-Damaging Properties of Human Neutrophils

Neutrophils, the most abundant subset of leukocytes in the blood, play a pivotal role in host response against invading pathogens. However, in respiratory diseases, excessive infiltration and activation of neutrophils can lead to tissue damage. Tanimilast-international non-proprietary name of CHF6001—is a novel inhaled phosphodiesterase 4 (PDE4) inhibitor in advanced clinical development for the treatment of chronic obstructive pulmonary disease (COPD), a chronic inflammatory lung disease where neutrophilic inflammation plays a key pathological role. Human neutrophils from healthy donors were exposed to pro-inflammatory stimuli in the presence or absence of tanimilast and budesonide—a typical inhaled corticosteroid drug-to investigate the modulation of effector functions including adherence to endothelial cells, granule protein exocytosis, release of extracellular DNA traps, cytokine secretion, and cell survival. Tanimilast significantly decreased neutrophil-endothelium adhesion, degranulation, extracellular DNA traps casting, and cytokine secretion. In contrast, it promoted neutrophil survival by decreasing both spontaneous apoptosis and cell death in the presence of pro-survival factors. The present work suggests that tanimilast can alleviate the severe tissue damage caused by massive recruitment and activation of neutrophils in inflammatory diseases such as COPD.

Exposure-Response and Clinical Outcome Modeling of Inhaled Budesonide/Formoterol Combination in Asthma Patients

Exposure-response and clinical outcome (CO) model for inhaled budesonide/formoterol was developed to quantify the relationship among pharmacokinetics (PK), pharmacodynamics (PD) and CO of the drugs and evaluate the covariate effect on model parameters. Sputum eosinophils cationic proteins (ECP) and forced expiratory volume (FEV1) were selected as PD markers and asthma control score was used as a clinical outcome. One- and two-compartment models were used to describe the PK of budesonide and formoterol, respectively. The indirect response model (IDR) was used to describe the PD effect for ECP and FEV1. In addition, the symptomatic effect on the disease progression model for CO was connected with IDR on each PD response. The slope for the effect of ECP and FEV1 to disease progression were estimated as 0.00008 and 0.644, respectively. Total five covariates (ex. ADRB2 genotype etc.) were searched using a stepwise covariate modeling method, however, there was no significant covariate effect. The results from the simulation study were showed that a 1 puff b.i.d. had a comparable effect of asthma control with a 2 puff b.i.d. As a result, the 1 puff b.i.d. of combination drug could be suggested as a standardized dose to minimize the side effects and obtain desired control of disease compared to the 2 puff b.i.d.

Targeting neutrophils using novel drug delivery systems in chronic respiratory diseases

Neutrophils are essential effector cells of immune system for clearing the extracellular pathogens during inflammation and immune reactions. Neutrophils play a major role in chronic respiratory diseases. In respiratory diseases such as asthma, chronic obstructive pulmonary disease, cystic fibrosis, lung cancer and others, there occurs extreme infiltration and activation of neutrophils followed by a cascade of events like oxidative stress and dysregulated cellular proteins that eventually result in apoptosis and tissue damage. Dysregulation of neutrophil effector functions including delayed neutropil apoptosis, increased neutrophil extracellular traps in the pathogenesis of asthma, and chronic obstructive pulmonary disease enable neutrophils as a potential therapeutic target. Accounting to their role in pathogenesis, neutrophils present as an excellent therapeutic target for the treatment of chronic respiratory diseases. This review highlights the current status and the emerging trends in novel drug delivery systems such as nanoparticles, liposomes, microspheres, and other newer nanosystems that can target neutrophils and their molecular pathways, in the airways against infections, inflammation, and cancer. These drug delivery systems are promising in providing sustained drug delivery, reduced therapeutic dose, improved patient compliance, and reduced drug toxicity. In addition, the review also discusses emerging strategies and the future perspectives in neutrophil-based therapy.

In vitro anti-inflammatory effects of AZD8999, a novel bifunctional muscarinic acetylcholine receptor antagonist /β2-adrenoceptor agonist (MABA) compound in neutrophils from COPD patients

Recent evidence indicates that AZD8999 (LAS190792), a novel muscarinic acetylcholine receptor antagonist and β2-adrenoceptor agonist (MABA) in development for chronic respiratory diseases, induces potent and sustained relaxant effects in human bronchi by adressing both muscarinic acetylcholine receptors and β2-adrenoceptor. However, the anti-inflammatory effects of the AZD8999 monotherapy or in combination with corticosteroids are unknown. This study investigates the anti-inflammatory effects of AZD8999 in monotherapy and combined with fluticasone propionate in neutrophils from healthy and chronic obstructive pulmonary disease (COPD) patients. Peripheral blood neutrophils from healthy and COPD patients were incubated with AZD8999 and fluticasone propionate, individually or in combination, for 1h followed by lipopolysaccharide (LPS) stimulation for 6h. The IL-8, MMP9, IL-1β, and GM-CSF release was measured in cell culture supernatants. AZD8999 shows ~ 50% maximum inhibitory effect and similar potency inhibiting the released cytokines in neutrophils from healthy and COPD patients. However, while fluticasone propionate suppresses mediator release in neutrophils from healthy patients, COPD neutrophils are less sensitive. The combination of non-effective concentrations of AZD8999 (0.01nM) with non-effective concentrations of fluticasone propionate (0.1nM) shows synergistic anti-inflammatory effects. The studied mechanisms that may be involved in the synergistic anti-inflammatory effects of this combination include the increase of glucocorticoid receptor (GR)α and MKP1 expression, the induction of glucocorticoid response element (GRE) activation and the decrease of ERK1/2, P38 and GR-Ser226 phosphorylations compared with monotherapies. In summary, AZD8999 shows anti-inflammatory effects in neutrophils from COPD patients and induces synergistic anti-inflammatory effects when combined with fluticasone propionate, supporting the use of MABA/ICS combination therapy in COPD.

Comparison of fluticasone propionate and budesonide on COPD macrophage and neutrophil function

Background

Inhaled corticosteroid use is associated with increased rates of pneumonia in COPD patients. The underlying mechanism is unknown, although recent data suggest that pneumonia is more frequent in patients treated with fluticasone propionate (FP) than budesonide. Macrophages and neutrophils from COPD patients are deficient in clearing bacteria, and this might explain increased bacterial colonization in COPD. Inhaled corticosteroid may further suppress this response; therefore, we examined the effect of FP and budesonide on phagocytosis of common respiratory pathogens by monocyte-derived macrophages (MDMs) and neutrophils.

Methods

MDMs from COPD patients (n=20–24) were preincubated with FP or budesonide for 1 or 18 hours, after which phagocytosis of fluorescently labeled inert beads or heat-killed Haemophilus influenzae/Streptococcus pneumoniae were measured fluorimetrically after 1 or 4 hours. Additionally, CXCL8, IL6, and TNFα concentrations in supernatants by ELISA, MDM-scavenger-receptor expression by flow cytometry, and MDM ability to kill bacteria were measured. Neutrophils from COPD patients (n=8) were preincubated with corticosteroids for 1 hour and bacteria phagocytosis measured by flow cytometry.

Results

After 1 hour’s preincubation, neither corticosteroid altered MDM phagocytosis of beads or H. influenzae; however, budesonide (10⁻⁷ M) increased S. pneumoniae phagocytosis by 23% (P<0.05). After 18 hours’ preincubation, neither corticosteroid altered MDM phagocytosis of any prey, although H. influenzae phagocytosis by budesonide was significantly greater compared to FP at 10⁻⁶ and 10⁻⁵ M (P<0.05). The 1-hour preincubation with either corticosteroid inhibited bacteria-induced CXCL8 release (at 10⁻⁷ and 10⁻⁵ M, P<0.05); however, this effect was lost at 18-hour preincubation. There was no change in receptor expression, bacterial killing, or neutrophil phagocytosis by either corticosteroid.

Conclusion

These data suggest that dissolved FP and budesonide do not have an overall effect on MDM or neutrophil phagocytosis of bacteria.

Protective effects of tiotropium alone or combined with budesonide against cadmium inhalation induced acute neutrophilic pulmonary inflammation in rats

As a potent bronchodilator, the anti-inflammatory effects of tiotropium and its interaction with budesonide against cadmium-induced acute pulmonary inflammation were investigated. Compared to values obtained in rats exposed to cadmium, cytological analysis indicated a significant decrease of total cell and neutrophil counts and protein concentration in bronchoalveolar lavage fluid (BALF) in rats pretreated with tiotropium (70μg/15ml or 350μg/15ml). Zymographic tests showed a decrease of MMP-2 activity in BALF in rats pretreated only with high concentration of tiotropium. Histological examination revealed a significant decrease of the severity and extent of inflammatory lung injuries in rats pretreated with both tested concentrations of tiotropium. Though tiotropium (70μg/15ml) or budesonide (250μg/15ml) could not reduce cadmium-induced bronchial hyper-responsiveness, their combination significantly decreased bronchial contractile response to methacholine. These two drugs separately decreased the neutrophil number and protein concentration in BALF but no significant interaction was observed when both drugs were combined. Although no inhibitory effects on MMP-2 and MMP-9 was observed in rats pretreated with budesonide alone, the combination with the ineffective dose of tiotropium induced a significant reduction on these parameters. The inhibitory effect of tiotropium on lung injuries was not influenced by budesonide which alone induced a limited action on the severity and extent of inflammatory sites. Our findings show that tiotropium exerts anti-inflammatory effects on cadmium-induced acute neutrophilic pulmonary inflammation. The combination of tiotropium with budesonide inhibits cadmium-induced inflammatory injuries with a synergistic interaction on MMP-2 and MMP-9 activity and airway hyper-responsiveness.

Lung inflammatory and oxidative alterations after exogenous surfactant therapy fortified with budesonide in rabbit model of meconium aspiration syndrome

Meconium aspiration syndrome (MAS) triggers inflammatory and oxidative pathways which can inactivate both pulmonary surfactant and therapeutically given exogenous surfactant. Glucocorticoid budesonide added to exogenous surfactant can inhibit inflammation and thereby enhance treatment efficacy. Neonatal meconium (25 mg/ml, 4 ml/kg) was administered intratracheally (i.t.) to rabbits. When the MAS model was prepared, animals were treated with budesonide i.t. (Pulmicort, 0.25 mg/kg, M+B); with surfactant lung lavage (Curosurf®, 10 ml/kg, 5 mg phospholipids/ml, M+S) followed by undiluted Curosurf® i.t. (100 mg phospholipids/kg); with combination of budesonide and surfactant (M+S+B); or were untreated (M); or served as controls with saline i.t. instead of meconium (C). Animals were oxygen-ventilated for additional 5 h. Cell counts in the blood and bronchoalveolar lavage fluid (BAL), lung edema formation (wet/dry weight ratio), oxidative damage of lipids/ proteins and inflammatory expression profiles (IL-2, IL-6, IL-13, TNF-alpha) in the lung homogenate and plasma were determined. Combined surfactant+budesonide therapy was the most effective in reduction of neutrophil counts in BAL, oxidative damage, levels and mRNA expression of cytokines in the lung, and lung edema formation compared to untreated animals. Curosurf fortified with budesonide mitigated lung inflammation and oxidative modifications what indicate the perspectives of this treatment combination for MAS therapy.

Impaired anti-inflammatory action of glucocorticoid in neutrophil from patients with steroid-resistant asthma

BACKGROUND

Steroid resistant (SR) asthma is characterized by persistent airway inflammation that fails to resolve despite treatment with high doses of corticosteroids. Furthermore, SR patient airways show increased numbers neutrophils, which are less responsive to glucocorticoid. The present study seeks to determine whether dexamethasone (DEX) has different effect on neutrophils from steroid sensitive (SS) asthmatics compared to SR asthmatics.

METHODS

Adults with asthma (n = 38) were classified as SR or SS based on changes in lung FEV1% following a one-month inhaled corticosteroid (ICS) treatment. Blood samples were collected from all patients during their first visit of the study. Neutrophils isolated from the blood were cultured with dexamethasone and/or atopic asthmatic serum for 18 h. The mRNA expression of mitogen-activated protein kinase phosphatase-1 (MKP-1), a glucocorticoid transactivation target, and glucocorticoid-induced transcript 1 (GLCCI1), an early marker of glucocorticoid-induced apoptosis whose expression was associated with the response to inhaled glucocorticoids in asthma , was determined by real-time PCR, and ELISA was used to assess the pro-inflammatory cytokine IL-8 levels in the supernatant. Constitutive neutrophil apoptosis was detected by flow cytometry.

RESULTS

DEX significantly induced MKP-1 expression in both patients with SS and SR patients in a concentration-dependent manner, but greater induction was observed for SS patients at a low concentration (10^-6 M). Asthmatic serum alone showed no MKP-1expression, and there was impaired induction of MKP-1 by DEX in SR asthma patients. The expression of GLCCI1 was not induced in neutrophils with DEX or DEX/atopic asthmatic serum combination. Greater inhibition of IL-8 production was observed in neutrophils from patients with SS asthma treated with DEX/atopic asthmatic serum combination compared with SR asthma patients, though DEX alone showed the same effect on neutrophils from SS and SR asthma patients. Meanwhile, DEX dependent inhibition of constitutive neutrophil apoptosis was similar between SS asthma and SR asthma patients.

CONCLUSIONS

DEX exerted different effects on neutrophils from patients with SS asthma and SR asthma, which may contribute to glucocorticoid insensitivity.

The effects of a CXCR1/CXCR2 antagonist on neutrophil migration in mild atopic asthmatic subjects

BACKGROUND

Neutrophils are effector cells recruited to airways in patients with asthma. Migration of neutrophils occurs predominantly through activation of the CXCR1 and CXCR2 receptors by CXC chemokines, including IL-8 and Gro-α. The dual CXCR1/CXCR2 antagonist SCH 527123 has been developed to target neutrophil migration to alleviate airway neutrophilia. This study investigated the effects of SCH 527123 on neutrophil levels within the bone marrow, peripheral blood and airways, and on isolated bone marrow and peripheral blood neutrophil migration from mild allergic asthmatics.

METHODS

Thirteen subjects with mild allergic asthma completed a double blind, placebo-controlled, multi-center crossover study and were randomized to daily dosing of 30 mg SCH 527123 and placebo for 8 days. Subjects provided bone marrow, peripheral blood and sputum samples pre-dosing and on the last day of dosing. Neutrophil numbers were quantified in all samples and chemotaxis assays were performed on neutrophils purified from bone marrow and peripheral blood.

RESULTS

Neutrophil numbers fell significantly in the peripheral blood and sputum following treatment with SCH 527123 compared to placebo treatment. No change in neutrophil numbers was observed in bone marrow. SCH 527123 reduced IL-8-induced migration of purified peripheral blood neutrophils (p < 0.05), but had limited effects on migration of neutrophils purified from bone marrow.

CONCLUSIONS

The results from this study demonstrate that oral administration of the dual CXCR1/CXCR2 antagonist SCH 527123 reduces neutrophil levels in the circulation and airways through inhibition of migration. There were no toxic effects of SCH 527123 on granulocytic progenitor cells in the bone marrow.

Chemokine receptors expression on CD3+ blood cells in bronchial asthma

PURPOSE

Chemokines and their receptors participate in pathomechanism of bronchial asthma. The aim of the study was to analyze the pattern of chemokine receptor expression on T cells in severe asthmatics and to compare to mild-to-moderate patients and controls.

MATERIAL/METHODS

Flow cytometric analysis of CXCR1, CXCR2, CXCR3, CCR3, CCR4, CCR5, CCR7, CCR8 expression on CD3(+)CD8(-) and CD3(+)CD8(+) cells was performed in patients with different severity of chronic asthma and in controls.

RESULTS

Percentages of CD3(+)CD8(+) cells expressing CXCR1 were significantly lower in severe asthmatic than in mild-to-moderate asthmatics and in controls. Percentages of CD3(+)CD8(+) cells expressing CCR7 were significantly lower in the severe asthma group than in control group. Percentages of CD3(+)CD8(-) cells expressing CXCR1, CXCR2 and CCR8 were significantly lower in the severe asthma group than in mild-to-moderate asthmatics and in controls. The number of cells CD3(+)CD8(-) and CD3(+)CD8(+) expressing of CXCR1 was significantly lower in the group of patients using more than 800μg of budesonide daily than in the group of patients using less than 400μg of budesonide. Percentages of CD3(+)CD8(-) cells expressing CXCR3, CCR4 and CCR5 were visibly higher (not significantly) in chronic mild-to-moderate asthma than in healthy controls and severe asthmatics.

CONCLUSIONS

These results may indicate impairment of some chemokine expression on T cells in severe asthma patients. Moreover participation of both chemokine receptors related to Th1 and Th2 responses in mild-to-moderate asthma and attenuation of these responses in severe asthma has been suggested.

Formoterol is more effective than salmeterol in suppressing neutrophil reactivity

Formoterol suppresses neutrophil reactivity in vitro; in COPD, this may contribute to anti-inflammatory efficacy http://ow.ly/Qr9fE.

The long-acting β2 -adrenoceptor agonist olodaterol attenuates pulmonary inflammation

Background and Purpose

β₂-adrenoceptor agonists are widely used in the management of obstructive airway diseases. Besides their bronchodilatory effect, several studies suggest inhibitory effects on various aspects of inflammation. The aim of our study was to determine the efficacy of the long-acting β₂-adrenoceptor agonist olodaterol to inhibit pulmonary inflammation and to elucidate mechanism(s) underlying its anti-inflammatory actions.

Experimental Approach

Olodaterol was tested in murine and guinea pig models of cigarette smoke- and LPS-induced lung inflammation. Furthermore, effects of olodaterol on the LPS-induced pro-inflammatory mediator release from human parenchymal explants, CD11b adhesion molecule expression on human granulocytes TNF-α release from human whole blood and on the IL-8-induced migration of human peripheral blood neutrophils were investigated.

Key Results

Olodaterol dose-dependently attenuated cell influx and pro-inflammatory mediator release in murine and guinea pig models of pulmonary inflammation. These anti-inflammatory effects were observed at doses relevant to their bronchodilatory efficacy. Mechanistically, olodaterol attenuated pro-inflammatory mediator release from human parenchymal explants and whole blood and reduced expression of CD11b adhesion molecules on granulocytes, but without direct effects on IL-8-induced neutrophil transwell migration.

Conclusions and Implications

This is the first evidence for the anti-inflammatory efficacy of a β₂-adrenoceptor agonist in models of lung inflammation induced by cigarette smoke. The long-acting β₂-adrenoceptor agonist olodaterol attenuated pulmonary inflammation through mechanisms that are separate from direct inhibition of bronchoconstriction. Furthermore, the in vivo data suggest that the anti-inflammatory properties of olodaterol are maintained after repeated dosing for 4 days.

Anti-inflammatory and anti-fibrotic profile of fish oil emulsions used in parenteral nutrition-associated liver disease

Home parenteral nutrition (PN) is associated with many complications including severe hepatobiliary dysfunction. Commercial ω-6 fatty acid-soybean based-lipid emulsions in PN may mediate long term PN associate liver disease (PNALD) whereas ω-3-fish oil parenteral emulsions have shown to reverse PNALD in children. However, its clinical effectiveness in adults has been scarcely reported. In this work, we study the role of soybean and fish oil lipid commercial emulsions on inflammatory and profibrotic liver markers in adults with long term PNALD and in in vitro cellular models. Inflammatory and profibrotic markers were measured in serum of ten adults with long term PNALD and in culture supernatants of monocytes. Liver epithelial to mesenchymal transition (EMT) was induced by transforming growth factor beta 1 (TGFβ1) to evaluate in vitro liver fibrosis. Omegaven®, a 100% fish oil commercial emulsion, was infused during four months in two patients with severe long term PNALD reversing, at the first month, the inflammatory, profibrotic and clinical parameters of PNALD. The effect was maintained during the treatment course but impaired when conventional lipid emulsions were reintroduced. The other patients under chronic soybean oil-based PN showed elevated inflammatory and profibrotic parameters. In vitro human monocytes stimulated with lipopolysaccharide induced a strong inflammatory response that was suppressed by Omegaven®, but increased by soybean emulsions. In other experiments, TGFβ1 induced EMT that was suppressed by Omegaven® and enhanced by soybean oil lipid emulsions. Omegaven® improves clinical, anti-inflammatory and anti-fibrotic parameters in adults with long-term home PNALD.

Alterations in the profile of blood neutrophil membrane receptors caused by in vivo adrenocorticotrophic hormone actions

Elevated levels of adrenocorticotrophic hormone (ACTH) mobilize granulocytes from bone marrow into the blood, although these neutrophils are refractory to a full migratory response into inflamed tissues. Here, we investigated the dependence of glucocorticoid receptor activation and glucocorticoid-regulated protein annexin A1 (ANXA1) on ACTH-induced neutrophilia and the phenotype of blood neutrophil after ACTH injection, focusing on adhesion molecule expressions and locomotion properties. ACTH injection (5 μg ip, 4 h) induced neutrophilia in wild-type (WT) mice and did not alter the elevated numbers of neutrophils in RU-38486 (RU)-pretreated or ANXA1(-/-) mice injected with ACTH. Neutrophils from WT ACTH-treated mice presented higher expression of Ly6G⁺ANXA1(high), CD18(high), CD62L(high), CD49(high), CXCR4(high), and formyl-peptide receptor 1 (FPR1(low)) than those observed in RU-pretreated or ANXA1(-/-) mice. The membrane phenotype of neutrophils collected from WT ACTH-treated mice was paralleled by elevated fractions of rolling and adherent leukocytes to the cremaster postcapillary venules together with impaired neutrophil migration into inflamed air pouches in vivo and in vitro reduced formyl-methionyl-leucyl-phenylalanine (fMLP) or stromal-derived factor-1 (SDF-1α)-induced chemotaxis. In an 18-h senescence protocol, neutrophils from WT ACTH-treated mice had a higher proportion of ANXAV(low)/CXCR4(low), and they were less phagocytosed by peritoneal macrophages. We conclude that alterations on HPA axis affect the pattern of membrane receptors in circulating neutrophils, which may lead to different neutrophil phenotypes in the blood. Moreover, ACTH actions render circulating neutrophils to a phenotype with early reactivity, such as in vivo leukocyte-endothelial interactions, but with impaired locomotion and clearance.

Roflumilast N-oxide reverses corticosteroid resistance in neutrophils from patients with chronic obstructive pulmonary disease

BACKGROUND

Glucocorticoid functions are markedly impaired in patients with chronic obstructive pulmonary disease (COPD). The phosphodiesterase 4 inhibitor roflumilast N-oxide (RNO) is the active metabolite of roflumilast approved as a treatment to reduce the risk of exacerbations in patients with severe COPD.

OBJECTIVE

We sought to characterize the differential effects of RNO versus corticosteroids and their potential additive/synergistic effect in neutrophils from patients with COPD, thus providing scientific rationale for the combination of roflumilast with corticosteroids in the clinic.

METHODS

Peripheral blood neutrophils were isolated from patients with COPD (n = 32), smokers (n = 7), and healthy nonsmokers (n = 25). Levels of IL-8, matrix metallopeptidase 9 (MMP-9), and biomarkers of glucocorticoid resistance were determined by using ELISA and RT-PCR. Neutrophils were incubated with dexamethasone (0.1 nmol/L to 1 μmol/L), RNO (0.1 nmol/L to 1 μmol/L), or the combination of 1 nmol/L RNO plus 10 nmol/L DEX and stimulated with LPS (1 μg/mL) or cigarette smoke extract 5%; levels of IL-8, MMP-9, and other biomarkers were measured at the end of the incubation period.

RESULTS

Peripheral neutrophils from patients with COPD showed a primed phenotype with an increased basal release of IL-8 and MMP-9 and expressed a corticosteroid resistance molecular profile characterized by an increase in phosphoinositide 3-kinase δ, macrophage migration inhibitory factor, and glucocorticoid receptor β expression and a decrease in HDAC activity and mitogen-activated protein kinase phosphatase 1 expression. RNO demonstrated robust anti-inflammatory effects on neutrophils from patients with COPD, reversing their resistance to corticosteroids. The combination of RNO and dexamethasone showed additive/synergistic effects, which were consistent with the reversal of corticosteroid-resistant molecular markers by RNO.

CONCLUSION

RNO reverses corticosteroid resistance and shows strong anti-inflammatory effects alone or in combination with corticosteroids on neutrophils from patients with COPD.

Characterizing asthma from a drop of blood using neutrophil chemotaxis

Asthma is a chronic inflammatory disorder that affects more than 300 million people worldwide. Asthma management would benefit from additional tools that establish biomarkers to identify phenotypes of asthma. We present a microfluidic solution that discriminates asthma from allergic rhinitis based on a patient's neutrophil chemotactic function. The handheld diagnostic device sorts neutrophils from whole blood within 5 min, and generates a gradient of chemoattractant in the microchannels by placing a lid with chemoattractant onto the base of the device. This technology was used in a clinical setting to assay 34 asthmatic (n = 23) and nonasthmatic, allergic rhinitis (n = 11) patients to establish domains for asthma diagnosis based on neutrophil chemotaxis. We determined that neutrophils from asthmatic patients migrate significantly more slowly toward the chemoattractant compared with nonasthmatic patients (P = 0.002). Analysis of the receiver operator characteristics of the patient data revealed that using a chemotaxis velocity of 1.55 μm/min for asthma yields a diagnostic sensitivity and specificity of 96% and 73%, respectively. This study identifies neutrophil chemotaxis velocity as a potential biomarker for asthma, and we demonstrate a microfluidic technology that was used in a clinical setting to perform these measurements.

Inhaled corticosteroid treatment for 6 months was not sufficient to normalize phagocytosis in asthmatic children

Background

Corticosteroids are the first-line therapy for asthma; however, the effect of corticosteroids on the innate immune system remains unclear. This study’s objective was to evaluate the effect of inhaled corticosteroid therapy (ICT) on phagocytic functions.

Methods

To evaluate the impact of ICT, the phagocytosis of Saccharomyces cerevisiae by blood monocytes and neutrophils and the production of superoxide anions were assessed before and after three and six months of ICT treatment in 58 children with persistent asthma and 21 healthy controls.

Results

We showed that the phagocytic capacity of monocytes and neutrophils that occurred via pattern recognition receptors or was mediated by complement and immunoglobulin receptors in asthmatic children before treatment was significantly lower than in healthy controls (p<0.05, Mann–Whitney test) and was not influenced by the severity of the clinical form of the disease. Although there was clinical improvement with treatment, ICT for 6 months was not sufficient to normalize phagocytosis by the phagocytes. Superoxide anion production was also decreased in the asthmatic children before treatment, and ICT normalized the O^- production only for children with mild persistent asthma when assessed at baseline but caused this function to decrease after stimulation (p<0.05, Kruskal-Wallis test).

Conclusions

Our data suggest that an immunodeficiency in phagocytes remained even after treatment. However, this immunodeficiency does not appear to correspond with the clinical evolution of asthma because an improvement in clinical parameters occurred.

Increased neutrophil migration in smokers with or without chronic obstructive pulmonary disease

BACKGROUND AND OBJECTIVE

The number of airway neutrophils is increased in chronic obstructive pulmonary disease (COPD), and this may have a central pathophysiological role in the disease. In addition, activation of neutrophils increases their migration into sites of injury. We hypothesize that circulating neutrophils are activated in smokers.

METHODS

Peripheral blood neutrophils were isolated from healthy non-smokers (n = 15), and smokers with (n = 15) or without COPD (n = 15), who were matched with regard to cumulative tobacco exposure, and chemotactic responses to N-formyl-methionyl-leucyl-phenylalanine (fMLP), interleukin-8 (IL-8, CXCL8) and leukotriene B(4) (LTB(4)) were assessed using the ChemoTx System (Neuro Probe Inc., Gaithersburg, MD, USA). Serum tumour necrosis factor-α (TNF-α) concentrations were measured by ELISA. Surface expression of the neutrophil activation marker, CD11b, was measured by flow cytometry.

RESULTS

The chemotactic response to CXCL8 was increased in smokers with or without COPD (P < 0.05). Migration towards LTB(4) was increased in smokers without COPD compared with non-smokers (P < 0.05), whereas there was no difference in fMLP-induced chemotaxis between the groups. There was a correlation between serum TNF-α levels and migration induced by IL-8 (Rho = 0.442; P = 0.038) and LTB(4) (Rho = 0.428; P = 0.044) in the smokers. Furthermore, there was a tendency towards higher CD11b expression in the COPD group (P = 0.057).

CONCLUSIONS

Chemotaxis of circulating neutrophils towards CXCL8, and partly towards LTB(4), is increased in smokers, indicating a systemic influence of smoking on cell activation, irrespective of the presence of airflow limitation. The relationship between TNF-α and chemotactic response suggests that TNF-α is involved in neutrophil activation, resulting in enhanced migration.

Neutrophils are not less sensitive than other blood leukocytes to the genomic effects of glucocorticoids

Background

Neutrophils are generally considered less responsive to glucocorticoids compared to other inflammatory cells. The reported increase in human neutrophil survival mediated by these drugs partly supports this assertion. However, it was recently shown that dexamethasone exerts potent anti-inflammatory effects in equine peripheral blood neutrophils. Few comparative studies of glucocorticoid effects in neutrophils and other leukocytes have been reported and a relative insensitivity of neutrophils to these drugs could not be ruled out.

Objective

We assessed glucocorticoid-responsiveness in equine and human peripheral blood neutrophils and neutrophil-depleted leukocytes.

Methods

Blood neutrophils and neutrophil-depleted leukocytes were isolated from 6 healthy horses and 4 human healthy subjects. Cells were incubated for 5 h with or without LPS (100 ng/mL) alone or combined with hydrocortisone, prednisolone or dexamethasone (10⁻⁸ M and 10⁻⁶ M). IL-1β, TNF-α, IL-8, glutamine synthetase and GR-α mRNA expression was quantified by qPCR. Equine neutrophils were also incubated for 20 h with or without the three glucocorticoids and cell survival was assessed by flow cytometry and light microscopy on cytospin preparations.

Results

We found that glucocorticoids down-regulated LPS-induced pro-inflammatory mRNA expression in both cell populations and species. These drugs also significantly increased glutamine synthetase gene expression in both equine cell populations. The magnitude of glucocorticoid response between cell populations was generally similar in both species. We also showed that dexamethasone had a comparable inhibitory effect on pro-inflammatory gene expression in both human and equine neutrophils. As reported in other species, glucocorticoids significantly increase the survival in equine neutrophils.

Conclusions

Glucocorticoids exert genomic effects of similar magnitude on neutrophils and on other blood leukocytes. We speculate that the poor response to glucocorticoids observed in some chronic neutrophilic diseases such as severe asthma or COPD is not explained by a relative lack of inhibition of these drugs on pro-inflammatory cytokines expression in neutrophils.

Drug choices in autoimmune hepatitis: part A--Steroids

Prednisone and prednisolone are the mainstays of treatment for autoimmune hepatitis. Prednisone is converted in the liver to the active metabolite, prednisolone. The principal therapeutic action of prednisolone is to suppress cytokine gene expression and to inhibit the differentiation and proliferation of activated lymphocytes. It also has anti-inflammatory effects that include decreased production of adhesion molecules, increased apoptosis of lymphocytes and decreased hepatic collagen deposition. Advanced liver disease does not sufficiently suppress hepatic conversion of prednisone to warrant the preferential use of prednisolone. Budesonide combined with azathioprine has been more effective and safer than the conventional prednisone-based regimen when given for 6 months to treatment-naive patients. It is emerging as a frontline treatment, especially for noncirrhotic patients with uncomplicated disease.

Elevated placenta growth factor predicts pneumonia in patients with chronic obstructive pulmonary disease under inhaled corticosteroids therapy

Background

An increased incidence of pneumonia in patients with chronic obstructive pulmonary disease (COPD) under inhaled corticosteroid (ICS) therapy was noticed in previous studies. We performed a prospective study to elucidate the risk factors for the development of pneumonia in this group of patients.

Methods

A prospective, non-randomized study with patients diagnosed as having COPD from 2007 to 2008 identified in the Far Eastern Memorial Hospital were recruited. We recorded data for all patients, including clinical features and signs, demographic data, lung function status, and medications. Bio-markers such as C-reactive protein (CRP) and placenta growth factor (PlGF) were checked at first diagnosis. Every acute exacerbation was also recorded, especially pneumonia events, which were confirmed by chest radiography. Multivariate analysis was performed with stepwise logistic regression for pneumonia risk factors.

Results

274 patients were diagnosed as having COPD during the study period and 29 patients suffered from pneumonia with a prevalence of 10.6%. The rate was significantly higher in patients with ICS therapy (20/125, 16%) compared with those without ICS (9/149, 6%) (p = 0.02). We stratified ICS therapy into medium dose (500-999 ug/day fluticasone equivalent, 71 patients) and high dose (1000 ug/day and higher fluticasone equivalent, 54 patients) group. There was no statistical difference in the incidence of pneumonia between these two group (medium dose: 13/71, 18.3% vs. high dose: 7/54, 12.9%, p = 0.47). Multivariate analysis was performed to identify the risk factors for developing pneumonia and included forced expiratory volume in one second (FEV1) less than 40% of predicted (odds ratio (OR) 2.2, 95% confidence interval (CI): 1.1-6.9), ICS prescription ((OR) 2.4, 95% (CI): 1.3-8.7), the presence of diabetes mellitus (DM) (OR 2.6, 95% CI: 1.2-9.4) and PlGF level over 40 pg/L (OR 4.1, 95% CI: 1.5-9.9).

Conclusion

ICS therapy in patients with COPD increased the risk of pneumonia. However, there was no relationship between the incidence of pneumonia and dosage of ICS. Additionally, advanced COPD status, DM and elevated PlGF level were independent risk factors for the development of pneumonia. PlGF would be a good novel biomarker for predicting pneumonia.