Continuing benefits of the Montreal Protocol and protection of the stratospheric ozone layer for human health and the environment.

The protection of Earth's stratospheric ozone (O3) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O3. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O3, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge.

Defective monocyte-derived macrophage phagocytosis is associated with exacerbation frequency in COPD.

BACKGROUND: Lower airway bacterial colonisation (LABC) in COPD patients is associated with increased exacerbation frequency and faster lung function decline. Defective macrophage phagocytosis in COPD drives inflammation, but how defective macrophage function contributes to exacerbations is not clear. This study investigated the association between macrophage phagocytosis and exacerbation frequency, LABC and clinical parameters. METHODS: Monocyte-derived macrophages (MDM) were generated from 92 stable COPD patients, and at the onset of exacerbation in 39 patients. Macrophages were exposed to fluorescently labelled Haemophilus influenzae or Streptococcus pneumoniae for 4 h, then phagocytosis measured by fluorimetry and cytokine release by ELISA. Sputum bacterial colonisation was measured by PCR. RESULTS: Phagocytosis of H. influenzae was negatively correlated with exacerbation frequency (r = 0.440, p < 0.01), and was significantly reduced in frequent vs. infrequent exacerbators (1.9 × 103 RFU vs. 2.5 × 103 RFU, p < 0.01). There was no correlation for S. pneumoniae. There was no association between phagocytosis of either bacteria with age, lung function, smoking history or treatment with inhaled corticosteroids, or long-acting bronchodilators. Phagocytosis was not altered during an exacerbation, or in the 2 weeks post-exacerbation. In response to phagocytosis, MDM from exacerbating patients showed increased release of CXCL-8 (p < 0.001) and TNFα (p < 0.01) compared to stable state. CONCLUSION: Impaired COPD macrophage phagocytosis of H. influenzae, but not S. pneumoniae is associated with exacerbation frequency, resulting in pro-inflammatory macrophages that may contribute to disease progression. Targeting these frequent exacerbators with drugs that improve macrophage phagocytosis may prove beneficial.

A novel inhaled phosphodiesterase 4 inhibitor (CHF6001) reduces the allergen challenge response in asthmatic patients.

CHF6001 is an inhaled phosphodiesterase 4 (PDE4) inhibitor in development for the treatment of obstructive lung diseases. The efficacy and safety of CHF6001 were investigated in a double blind, placebo controlled, 3-way cross-over study using the allergen challenge model. Thirty-six atopic asthmatics who were not taking inhaled corticosteroids and who demonstrated a late asthmatic response (LAR) to inhaled allergen at screening were randomised to receive CHF6001 400 µg or 1200 µg or placebo administered once a day using a dry powder inhaler. The three treatment periods were 9 days; allergen challenges were performed on day 9 and induced sputum was obtained after 10 h from challenge. Washout periods between treatments were up to 5 weeks. Both CHF6001 doses significantly attenuated the LAR; the primary endpoint analysis showed that CHF6001 400 µg and 1200 µg caused reductions of 19.7% (p = 0.015) and 28.2% (p < 0.001) respectively of the weighted FEV1 AUC4-10h compared with placebo. The difference between the CHF6001 doses was not statistically significant (p = 0.223). Compared with placebo, CHF6001 caused greater reduction in sputum eosinophil counts, although these changes were not statistically significant. CHF6001 was well tolerated, with similar numbers of adverse events in each treatment period. This inhaled PDE4 inhibitor has the potential to provide clinical benefits in patients with atopic asthma.

Bronchoabsorption; a novel bronchoscopic technique to improve biomarker sampling of the airway.

BACKGROUND: Current techniques used to obtain lung samples have significant limitations and do not provide reproducible biomarkers of inflammation. We have developed a novel technique that allows multiple sampling methods from the same area (or multiple areas) of the lung under direct bronchoscopic vision. It allows collection of mucosal lining fluid and bronchial brushing from the same site; biopsy samples may also be taken. The novel technique takes the same time as standard procedures and can be conducted safely. METHODS: Eight healthy smokers aged 40-65 years were included in this study. An absorptive filter paper was applied to the bronchial mucosa under direct vision using standard bronchoscopic techniques. Further samples were obtained from the same site using bronchial brushings. Bronchoalveolar lavage (BAL) was obtained using standard techniques. Chemokine (C-C Motif) Ligand 20 (CCL20), CCL4, CCL5, Chemokine (C-X-C Motif) Ligand 1 (CXCL1), CXCL8, CXCL9, CXCL10, CXCL11, Interleukin 1 beta (IL-1ß), IL-6, Vascular endothelial growth factor (VEGF), Matrix metalloproteinase 8 (MMP-8) and MMP-9 were measured in exudate and BAL. mRNA was collected from the bronchial brushings for gene expression analysis. RESULTS: A greater than 10 fold concentration of all the biomarkers was detected in lung exudate in comparison to BAL. High yield of good quality RNA with RNA integrity numbers (RIN) between 7.6 and 9.3 were extracted from the bronchial brushings. The subset of genes measured were reproducible across the samples and corresponded to the inflammatory markers measured in exudate and BAL. CONCLUSIONS: The bronchoabsorption technique as described offers the ability to sample lung fluid direct from the site of interest without the dilution effects caused by BAL. Using this method we were able to successfully measure the concentrations of biomarkers present in the lungs as well as collect high yield mRNA samples for gene expression analysis from the same site. This technique demonstrates superior sensitivity to standard BAL for the measurement of biomarkers of inflammation. It could replace BAL as the method of choice for these measurements. This method provides a systems biology approach to studying the inflammatory markers of respiratory disease progression. TRIAL REGISTRATION: NHS Health Research Authority (13/LO/0256).

Integrated care pathways for airway diseases (AIRWAYS-ICPs).

The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will add value to existing public health knowledge by: 1) proposing a common framework of care pathways for chronic respiratory diseases, which will facilitate comparability and trans-national initiatives; 2) informing cost-effective policy development, strengthening in particular those on smoking and environmental exposure; 3) aiding risk stratification in chronic disease patients, using a common strategy; 4) having a significant impact on the health of citizens in the short term (reduction of morbidity, improvement of education in children and of work in adults) and in the long-term (healthy ageing); 5) proposing a common simulation tool to assist physicians; and 6) ultimately reducing the healthcare burden (emergency visits, avoidable hospitalisations, disability and costs) while improving quality of life. In the longer term, the incidence of disease may be reduced by innovative prevention strategies. AIRWAYSICPs was initiated by Area 5 of the Action Plan B3 of the European Innovation Partnership on Active and Healthy Ageing. All stakeholders are involved (health and social care, patients, and policy makers).

The effects of the novel SHIP1 activator AQX-1125 on allergen-induced responses in mild-to-moderate asthma.

BACKGROUND: SH2-containing inositol-5'-phosphatase 1 (SHIP1) is an endogenous inhibitor of the phosphoinositide-3-kinase pathway that is involved in the activation and chemotaxis of inflammatory cells. AQX-1125 is a first-in-class, oral SHIP1 activator with a novel anti-inflammatory mode of action. OBJECTIVE: To evaluate the effects of AQX-1125 on airway responses to allergen challenge in mild-to-moderate asthmatic patients. METHODS: A randomized, double-blind, placebo-controlled, two-way crossover study was performed in 22 steroid-naïve mild-to-moderate asthmatics with a documented late-phase response to inhaled allergen (LAR). AQX-1125 (450 mg daily) or placebo was administered orally for 7 days. Allergen challenge was performed on day 6 (2 h postdose), followed by methacholine challenge (day 7), and induced sputum collection and fractional exhaled nitric oxide (FeNO). RESULTS: AQX-1125 significantly attenuated the late-phase response compared with placebo (FEV1 4-10 h: mean difference 150 mL, 20%; P = 0.027) and significantly increased the minimum FEV1 during LAR (mean difference 180 mL; P = 0.014). AQX-1125 had no effect on the early-phase response. AQX-1125 showed a trend in reduction of sputum eosinophils, neutrophils and macrophages although this did not achieve significance as there were only 11 paired samples for analysis. There was no effect on methacholine responsiveness or FeNO. Pharmacokinetic data showed AQX-1125 was rapidly absorbed with geometric mean Cmax and AUC0-24 h values of 1417 ng/mL and 16 727 h ng/mL, respectively. AQX-1125 was well tolerated, but mild GI side-effects (dyspepsia, nausea and abdominal pain) were described in 4/22 subjects on active treatment. These side-effects were mild self-limiting, required no further treatment and did not lead to discontinuation of therapy. CONCLUSION AND CLINICAL RELEVANCE: AQX-1125, a novel oral SHIP1 activator, significantly reduces the late response to allergen challenge, with a trend to reduce airway inflammation. AQX-1125 was safe and well tolerated and merits further investigation in inflammatory disorders.

The Asthma Control Questionnaire as a clinical trial endpoint: past experience and recommendations for future use.

The goal of asthma treatment is to control the disease according to guidelines issued by bodies such as the Global Initiative for Asthma. Effective control is dependent upon evaluation of symptoms, initiation of appropriate treatment and minimization of the progressive adverse effects of the disease and its therapies. Although individual outcome measures have been shown to correlate with asthma control, composite endpoints are preferred to enable more accurate and robust monitoring of the health of the individual patient. A number of validated instruments are utilized to capture these component endpoints; however, there is no consensus on the optimal instrument for use in clinical trials. The Asthma Control Questionnaire (ACQ) has been shown to be a valid, reliable instrument that allows accurate and reproducible assessment of asthma control that compares favourably with other commonly used instruments. This analysis provides a summary of the use of ACQ in phase II, III and IV asthma trials. Comparisons between the ACQ and other instruments are also presented. Our analysis suggests that the ACQ is a valid and robust measure for use as a primary or secondary endpoint in future clinical trials.

Statins enhance the effects of corticosteroids on the balance between regulatory T cells and Th17 cells.

BACKGROUND: Plasticity of CD4(+) lymphocyte Th17/regulatory T cell (Treg) subsets is involved in the pathogenesis of chronic airway inflammatory diseases, such as asthma. Reversal of Th17/Treg cell balance towards Treg cells may be beneficial for the suppression of chronic Th2 cell-mediated inflammatory diseases, such as asthma. However, the effect of the combination of corticosteroids and a statin on the ratio of Treg/Th17 cells is unknown. OBJECTIVE: We investigated the in vitro effects of the combination of simvastatin and fluticasone propionate (FP) on the numbers of Treg and Th17 cells in asthmatic patients after co-incubation with monocyte-derived DCs (mDCs), and explored the underlying signalling pathways involved. METHODS: Using flow cytometry, we determined the effects of FP and simvastatin on Treg/Th17 balance after co-incubation of asthmatic CD4(+) T cells with mDCs. We also measured the relevant Treg and Th17-polarizing cytokines released from mDCs and also investigated the role of indoleamine 2, 3-dioxygenase (IDO) in this response. RESULTS: The combination of simvastatin and FP significantly increased Treg and concomitantly reduced Th17 cell numbers to a greater extent than FP or statin treatment alone. The enhancing effects of simvastatin on FP effects were mediated through the up-regulation of indoleamine 2, 3-dioxygenase and interleukin (IL)-10, together with down-regulation of IL-6 and IL-23 expression in mDCs. CONCLUSION: On the basis of this in vitro model of asthma, we suggest that the combination of a statin and a corticosteroid could augment the Treg/Th17 cell ratio and thus more effectively suppress airway inflammation in asthma patients. This may be particularly relevant in the treatment of severe asthma where Th17 cells are activated and linked to neutrophilic inflammation.

Expression of muscarinic receptors by human macrophages.

Macrophages increase in number and are highly activated in chronic obstructive pulmonary disease (COPD). Muscarinic receptor antagonists inhibit acetylcholine-stimulated release of neutrophilic chemoattractants, suggesting that acetylcholine may regulate macrophage responses. Therefore, expression and function of components of the non-neuronal cholinergic system in monocyte-macrophage cells was investigated. RNA was isolated from monocytes, monocyte-derived macrophages (MDMs), lung and alveolar macrophages from nonsmokers, smokers and COPD patients, and expression of the high-affinity choline transporter, choline acetyltransferase, vesicular acetylcholine transporter and muscarinic receptors (M(1)-M(5)) ascertained using real-time PCR. M(2) and M(3) receptor expression was confirmed using immunocytochemistry. Release of interleukin (IL)-8, IL-6 and leukotriene (LT)B(4) were measured by ELISA or EIA. All monocyte-macrophage cells expressed mRNA for components of the non-neuronal cholinergic system. Lung macrophages expressed significantly more M(1) mRNA compared with monocytes, and both lung macrophages and alveolar macrophages expressed the highest levels of M(3) mRNA. Expression of M(2) and M(3) protein was confirmed in MDMs and lung macrophages. Carbachol stimulated release of LTB(4) from lung macrophages (buffer 222.3 ± 75.1 versus carbachol 1,118 ± 622.4 pg · mL(-1); n = 15, p<0.05) but not IL-6 or IL-8. LTB(4) release was attenuated by the M(3) antagonist, 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (4-DAMP; half maximal effective concentration 5.2 ± 2.2 nM; n = 9). Stimulation of macrophage M(3) receptors promotes release of LTB(4), suggesting that anti-muscarinic agents may be anti-inflammatory.

Bradykinin-evoked sensitization of airway sensory nerves: a mechanism for ACE-inhibitor cough.

Cough accompanied by an increased sensitivity of the cough reflex is the most common symptom of inflammatory airway disease. This symptom is also frequently reported in patients receiving angiotensin-converting enzyme (ACE) inhibitors as therapy for heart failure or hypertension, although the underlying mechanism is unknown. We have investigated the possibility that the inflammatory peptide bradykinin, normally degraded by ACE, causes sensitization of airway sensory nerves and an enhancement of the cough reflex in conscious guinea pigs. Treatment of guinea pigs for two weeks with captopril led to an increased cough response to inhaled citric acid, which was prevented by concomitant treatment with the bradykinin receptor antagonist icatibant. A similar icatibant-sensitive enhancement of citric acid-evoked cough was seen in untreated animals after prior inhalation of bradykinin, although cough evoked by hypertonic saline was unaffected. In electrophysiological studies performed in vitro, responses of single vagal C fibers to capsaicin, applied to receptive fields of single-fiber units in the trachea, were also markedly increased after perfusion with bradykinin, whereas A delta fiber responses to hypertonic saline were unaffected. These results indicate that bradykinin-evoked sensitization of airway sensory nerves may underlie the pathogenesis of ACE-inhibitor cough. Bradykinin receptor antagonists may be of benefit in treating chronic cough seen with this and other inflammatory conditions.

Abnormal glucocorticoid receptor-activator protein 1 interaction in steroid-resistant asthma.

Glucocorticosteroids are a very effective treatment for asthma and other chronic inflammatory diseases. However, a small proportion of patients is resistant to the therapeutic effects of glucocorticoids. Pharmacokinetic and ligand binding studies suggest that the molecular abnormality in steroid resistance lies distal to nuclear translocation. We have previously reported that there is a decreased ability of glucocorticoid receptors (GR) to bind to the DNA-binding site in peripheral blood mononuclear cells (PBMC) after dexamethasone treatment. This reduced DNA binding was due to a decrease in the number of receptors available rather than an alteration in affinity for DNA. To study this reduced DNA binding, we examined the ability of the nuclear translocated transcription factors activator protein 1 (AP-1), nuclear factor kappa B (NF-kappa B) and cyclic AMP response element-binding protein (CREB) to bind to their DNA-binding sites and to interact with GR in PBMC from patients with steroid-sensitive and steroid-resistant asthma. There was a significant reduction in the interaction between GR and AP-1 in these steroid-resistant patients, although interaction with other transcription factors activated in inflammation (NF-kappa B and CREB) was unaffected. An increase in the basal levels of AP-1 DNA binding was also detected in the nuclei from steroid-resistant asthmatic patients. There were no differences in the amount of messenger RNA detected for the components of AP-1, c-Fos and c-Jun, nor in the sequences of these messenger RNAs. These results suggest either that the ability of the GR to bind to glucocorticoid response elements and AP-1 is altered in steroid-resistant patients or that increased levels of AP-1 prevent GR DNA binding, and that this may be the molecular basis of resistance to the antiinflammatory effect of steroids in these cells.

Effects of formoterol and salmeterol on cytokine release from monocyte-derived macrophages.

Pulmonary macrophages are a target for inhaled therapies. Combinations of long-acting beta(2)-agonists (LABA) and glucocorticosteroids have been developed for asthma and chronic obstructive pulmonary disease (COPD). This study examined two LABA, salmeterol and formoterol, and the glucocorticosteroid, budesonide, on cytokine release from monocyte-derived macrophages (MDM) to determine whether anti-inflammatory effects observed in patients are due to inhibition of macrophages. MDM were incubated in the absence or presence of LABA or budesonide prior to stimulation with lipopolysaccharide (LPS). Tumour necrosis factor (TNF)-alpha, granulocyte macrophage-colony stimulating factor (GM-CSF) and CXC chemokine ligand (CXCL)8 were measured by ELISA. Formoterol and salmeterol inhibited LPS-stimulated release of TNF-alpha (mean effective concentration (EC(50)) 2.4+/-1.8 and 3.5+/-2.7 nM, respectively; n = 11-16), GM-CSF (EC(50) 24.6+/-2.1 and 52.4+/-40.8 nM, respectively, n = 11-12) but not CXCL8 from LPS-stimulated MDM. Budesonide inhibited release of all three cytokines (EC(50) TNF-alpha: 1.2+/-0.4 nM; GM-CSF: 0.4+/-0.2 nM; CXCL8: 0.4+/-0.1 nM; n = 3-4). Formoterol but not salmeterol elevated cAMP in these cells. These effects were attenuated by beta-adrenoceptor antagonists, propranolol and ICI118551. Salmeterol (10(-7) M) also inhibited formoterol-induced cAMP and formoterol-mediated attenuation of cytokine release. Combining budesonide (0.3 nM) with formoterol, inhibited TNF-alpha release additively. LABA may inhibit inflammatory cytokine release from macrophages in a cAMP-independent manner and act additively with budesonide.

Defective macrophage phagocytosis of bacteria in COPD.

Exacerbations of chronic obstructive pulmonary disease (COPD) are an increasing cause of hospitalisations and are associated with accelerated progression of airflow obstruction. Approximately half of COPD exacerbations are associated with bacteria and many patients have lower airways colonisation. This suggests that bacterial infection in COPD could be due to reduced pathogen removal. This study investigated whether bacterial clearance by macrophages is defective in COPD. Phagocytosis of fluorescently labelled polystyrene beads and Haemophillus influenzae and Streptococcus pneumoniae by alveolar macrophages and monocyte-derived macrophages (MDM) was assessed by fluorimetry and flow cytometry. Receptor expression was measured by flow cytometry. Alveolar macrophages and MDM phagocytosed polystyrene beads similarly. There was no difference in phagocytosis of beads by MDM from COPD patients compared with cells from smokers and nonsmokers. MDM from COPD patients showed reduced phagocytic responses to S. pneumoniae and H. influenzae compared with nonsmokers and smokers. This was not associated with alterations in cell surface receptor expression of toll-like receptor (TLR)2, TLR4, macrophage receptor with collagenous structure, cluster of differentiation (CD)163, CD36 or mannose receptor. Budesonide, formoterol or azithromycin did not suppress phagocytosis suggesting that reduced responses in COPD MDM were not due to medications. COPD macrophage innate responses are suppressed and may lead to bacterial colonisation and increased exacerbation frequency.

The airway vasculature: recent advances and clinical implications.

It is increasingly recognised that the airway circulation plays an important role in airway diseases, either through a change in blood flow or through microvascular leakage. Most of the information available regarding the anatomy and physiology of bronchial blood flow and its regulation has necessarily derived from animal studies. However, there have recently been important advances in understanding airway blood flow in airway disease in humans through the development of non-invasive methods and in the quantification of microvascular leakage using plasma markers. These studies have shown that bronchial blood flow is increased in patients with asthma but not in those with chronic obstructive pulmonary disease, confirming previous pathology investigations. Changes in bronchial blood flow may in part reflect the generation of new vascular vessels, a process known as "angiogenesis" which is caused by airway inflammation. Angiogenesis and the resulting plasma leak affect airway physiology, drug clearance and its bioavailability. This review discusses the anatomy, physiology and regulation of bronchial blood flow in the normal and diseased lung, In addition, it analyses the effect of current medical treatment and discusses the potential use of new anti-angiogenesis medications. The development of non-invasive assessment of bronchial blood flow and the study of angiogenesis have provided a tool to investigate airway physiology in vivo; these advances will contribute to a better understanding of inflammatory airway diseases as well as the implication of these findings to management.

Low-dose theophylline enhances the anti-inflammatory effects of steroids during exacerbations of COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory response mainly to cigarette smoke that flares up during exacerbations of the disease (ECOPD). Reduced activity of histone deacetylases (HDAC) contributes to enhanced inflammation in stable COPD. It was hypothesised that HDAC activity is further reduced during ECOPD and that theophylline, an HDAC activator, potentiates the anti-inflammatory effect of steroids in these patients. A study was performed to investigate HDAC activity during ECOPD and the effects of theophylline on the anti-inflammatory effects of steroids in a randomised single-blind controlled study. METHODS: 35 patients hospitalised with ECOPD and treated according to international guidelines (including systemic steroids) were randomised to receive or not to receive low-dose oral theophylline (100 mg twice daily). Before treatment and 3 months after discharge, HDAC and nuclear factor-kappaB (NF-kappaB) activity in sputum macrophages, the concentration of nitric oxide in exhaled air (eNO) and total antioxidant status (TAS), tumour necrosis factor alpha (TNFalpha), interleukin (IL)-6 and IL8 levels in sputum supernatants were measured. RESULTS: Patients receiving standard therapy showed decreased NF-kappaB activity, eNO concentration and sputum levels of TNFalpha, IL6 and IL8, as well as increased TAS during recovery of ECOPD, but HDAC activity did not change. The addition of low-dose theophylline increased HDAC activity and further reduced IL8 and TNFalpha concentrations. CONCLUSIONS: During ECOPD, low-dose theophylline increases HDAC activity and improves the anti-inflammatory effects of steroids. TRIAL REGISTRATION NUMBER: NCT00671151.

Association of increased CCL5 and CXCL7 chemokine expression with neutrophil activation in severe stable COPD.

BACKGROUND: Increased numbers of activated neutrophils have been reported in the bronchial mucosa of patients with stable chronic obstructive pulmonary disease (COPD), particularly in severe disease. OBJECTIVES: To investigate the expression of neutrophilic chemokines and adhesion molecules in bronchial biopsies from patients with stable COPD of different severity (GOLD stages I-IV) compared with age-matched control subjects, smokers with normal lung function and never smokers. METHODS: The expression of CCL5, CXCL1, 5, 6, 7 and 8, CXCR1, CXCR2, CD11b and CD44 was measured in the bronchial mucosa using immunohistochemistry, confocal immunofluorescence, real-time quantitative polymerase chain reaction (RT-QPCR) and Western blotting (WB). RESULTS: The numbers of CCL5+ epithelial cells and CCL5+ and CXCL7+ immunostained cells were increased in the bronchial submucosa of patients with stable severe COPD compared with control never smokers and smokers with normal lung function. This was also confirmed at the level of mRNA expression. The numbers of CCL5+ cells in the submucosa of patients with COPD were 2-15 times higher than any other chemokines. There was no correlation between the number of these cells and the number of neutrophils in the bronchial submucosa. Compared with control smokers, the percentage of neutrophils co-expressing CD11b and CD44 receptors was significantly increased in the submucosa of patients with COPD. CONCLUSION: The increased expression of CCL5 and CXCL7 in the bronchial mucosa of patients with stable COPD, together with an increased expression of extracellular matrix-binding receptors on neutrophils, may be involved in the pathogenesis of COPD.

Systemic manifestations and comorbidities of COPD.

Increasing evidence indicates that chronic obstructive pulmonary disease (COPD) is a complex disease involving more than airflow obstruction. Airflow obstruction has profound effects on cardiac function and gas exchange with systemic consequences. In addition, as COPD results from inflammation and/or alterations in repair mechanisms, the "spill-over" of inflammatory mediators into the circulation may result in important systemic manifestations of the disease, such as skeletal muscle wasting and cachexia. Systemic inflammation may also initiate or worsen comorbid diseases, such as ischaemic heart disease, heart failure, osteoporosis, normocytic anaemia, lung cancer, depression and diabetes. Comorbid diseases potentiate the morbidity of COPD, leading to increased hospitalisations, mortality and healthcare costs. Comorbidities complicate the management of COPD and need to be evaluated carefully. Current therapies for comorbid diseases, such as statins and peroxisome proliferator-activated receptor-agonists, may provide unexpected benefits for COPD patients. Treatment of COPD inflammation may concomitantly treat systemic inflammation and associated comorbidities. However, new broad-spectrum anti-inflammatory treatments, such as phosphodiesterase 4 inhibitors, have significant side-effects so it may be necessary to develop inhaled drugs in the future. Another approach is the reversal of corticosteroid resistance, for example with effective antioxidants. More research is needed on COPD comorbidities and their treatment.

Leukotriene B4 release by human lung macrophages via receptor- not voltage-operated Ca2+ channels.

Increased numbers of macrophages and neutrophils in the lung is a key feature of chronic obstructive pulmonary disease (COPD). The major neutrophil chemotactic agent in the airways of COPD patients is leukotriene (LT)B(4) and is released by macrophages. The present study examines the role and mechanism of Ca(2+) in platelet-activating factor (PAF)-stimulated LTB(4) release from human lung macrophages. Macrophages were isolated from lung tissue of subjects undergoing lung resection surgery and monocyte-derived macrophages (MDM) were obtained from nonsmokers, smokers without obstruction and COPD patients. Cells were stimulated with PAF and LTB(4) release and [Ca(2+)](i) was measured. Lung macrophages and MDM released LTB(4) following stimulation with PAF (mean effective concentration: 0.08+/-0.06 microM (n = 5) versus 0.17+/-0.12 microM (n = 17), respectively). Compared with MDM, lung macrophages released approximately eight-fold more LTB(4). Neither smoking nor COPD altered MDM responses. PAF-stimulated LTB(4) release was abrogated by ethylene glycol tetraacetic acid suggesting a role for extracellular Ca(2+). This was substantiated by using store-operated channel blockers econazole, SK&F96365 and Gd(3+). However, econazole and SK&F96365 were more effective in MDM than lung macrophages. Neither LOE908 nor nifedipine could attenuate this response. These data suggest that platelet-activating factor-stimulated leukotriene B(4) release from human lung macrophages is mediated, in part, by Ca(2+) influx through receptor- but not voltage-operated Ca(2+) channels.

Effect of low-dose theophylline plus beclometasone on lung function in smokers with asthma: a pilot study.

Smoking is common in asthma and is associated with worse asthma control and a reduced therapeutic response to corticosteroids. The present authors hypothesised that treating smokers with asthma with low-dose theophylline added to inhaled corticosteroids would enhance steroid sensitivity and thereby improve lung function and symptoms. In a double-blind, parallel group exploratory trial, 68 asthmatic smokers were randomised to one of three treatments for 4 weeks: inhaled beclometasone (200 microg day(-1)), theophylline (400 mg day(-1)) or both treatments combined. Outcome measures included change in lung function and Asthma Control Questionnaire (ACQ) scores. At 4 weeks, theophylline added to inhaled beclometasone produced an improvement in peak expiratory flow (39.9 L min(-1), 95% confidence intervals (CI) 10.9-68.8) and ACQ score (-0.47, 95% CI -0.91- -0.04) and a borderline improvement in pre-bronchodilator forced expiratory volume in one second (mean difference 165 mL, 95% CI -13-342) relative to inhaled corticosteroid alone. Theophylline alone improved the ACQ score (-0.55, 95% CI -0.99- -0.11), but not lung function. In the present pilot study, the combination of low-dose theophylline and inhaled beclometasone produced improvements in both lung function and symptoms in a group of smokers with asthma. Larger trials are required to extend and confirm these findings.

T helper type 17-related cytokine expression is increased in the bronchial mucosa of stable chronic obstructive pulmonary disease patients.

There are increased numbers of activated T lymphocytes in the bronchial mucosa of stable chronic obstructive pulmonary disease (COPD) patients. T helper type 17 (Th17) cells release interleukin (IL)-17 as their effector cytokine under the control of IL-22 and IL-23. Furthermore, Th17 numbers are increased in some chronic inflammatory conditions. To investigate the expression of interleukin (IL)-17A, IL-17F, IL-21, IL-22 and IL-23 and of retinoic orphan receptor RORC2, a marker of Th17 cells, in bronchial biopsies from patients with stable COPD of different severity compared with age-matched control subjects. The expression of IL-17A, IL-17F, IL-21, IL-22, IL-23 and RORC2 was measured in the bronchial mucosa using immunohistochemistry and/or quantitative polymerase chain reaction. The number of IL-22(+) and IL-23(+) immunoreactive cells is increased in the bronchial epithelium of stable COPD compared with control groups. In addition, the number of IL-17A(+) and IL-22(+) immunoreactive cells is increased in the bronchial submucosa of stable COPD compared with control non-smokers. In all smokers, with and without disease, and in patients with COPD alone, the number of IL-22(+) cells correlated significantly with the number of both CD4(+) and CD8(+) cells in the bronchial mucosa. RORC2 mRNA expression in the bronchial mucosa was not significantly different between smokers with normal lung function and COPD. Further, we report that endothelial cells express high levels of IL-17A and IL-22. Increased expression of the Th17-related cytokines IL-17A, IL-22 and IL-23 in COPD patients may reflect their involvement, and that of specific IL-17-producing cells, in driving the chronic inflammation seen in COPD.