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1.  Targeted lung denervation for moderate to severe COPD: a pilot study 
Thorax  2015;70(5):411-419.
Parasympathetic pulmonary nerves release acetylcholine that induces smooth muscle constriction. Disruption of parasympathetic pulmonary nerves improves lung function and COPD symptoms.
To evaluate ‘targeted lung denervation’ (TLD), a novel bronchoscopic therapy based on ablation of parasympathetic pulmonary nerves surrounding the main bronchi, as a potential therapy for COPD.
This 1-year, prospective, multicentre study evaluated TLD in patients with COPD forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) (FEV1/FVC <0.70; FEV1 30%–60% predicted). Patients underwent staged TLD at 20 watts (W) or 15 W following baseline assessment off bronchodilators. Assessments were repeated on tiotropium before treatment and off bronchodilators at 30, 90, 180, 270 and 365 days after TLD. The primary endpoint was freedom from documented and sustained worsening of COPD directly attributable to TLD to 1 year. Secondary endpoints included technical feasibility, change in pulmonary function, exercise capacity, and quality of life.
Twenty-two patients were included (n=12 at 20 W, n=10 at 15 W). The procedures were technically feasible 93% of the time. Primary safety endpoint was achieved in 95%. Asymptomatic bronchial wall effects were observed in 3 patients at 20 W. The clinical safety profiles were similar between the two energy doses. At 1 year, changes from baseline in the 20 W dose compared to the 15 W dose were: FEV1 (+11.6%±32.3 vs +0.02%±15.1, p=0.324), submaximal cycle endurance (+6.8 min±12.8 vs 2.6 min±8.7, p=0.277), and St George's Respiratory Questionnaire (−11.1 points ±9.1 vs −0.9 points ±8.6, p=0.044).
Bronchoscopic TLD, based on the concept of ablating parasympathetic pulmonary nerves, was feasible, safe, and well tolerated. Further investigation of this novel therapy is warranted.
Trial registration number
PMCID: PMC4413833  PMID: 25739911
COPD ÀÜ Mechanisms; Bronchoscopy
2.  Lung volume reduction coil treatment for patients with severe emphysema: a European multicentre trial 
Thorax  2014;69(11):980-986.
The lung volume reduction (LVR) coil is a minimally invasive bronchoscopic nitinol device designed to reduce hyperinflation and improve elastic recoil in severe emphysema. We investigated the feasibility, safety and efficacy of LVR coil treatment in a prospective multicentre cohort trial in patients with severe emphysema.
Patients were treated in 11 centres. Safety was evaluated by recording all adverse events, efficacy by the St George's Respiratory Questionnaire (SGRQ) as primary endpoint, and pulmonary function testing, modified Medical Research Council dyspnoea score (mMRC) and 6-min walk distance (6MWD) up to 12 months after the final treatment.
Sixty patients (60.9 ± 7.5 years, forced expiratory volume in 1 s (FEV1) 30.2 ± 6.3% pred) were bronchoscopically treated with coils (55 bilateral, 5 unilateral), with a median of 10 (range 5–15) coils per lobe. Within 30 days post-treatment, seven chronic obstructive pulmonary disease exacerbations (6.1%), six pneumonias (5.2%), four pneumothoraces (3.5%) and one haemoptysis (0.9%) occurred as serious adverse events. At 6 and 12 months, respectively, ΔSGRQ was −12.1±12.9 and −11.1±13.3 points, Δ6MWD was +29.7±74.1 m and +51.4±76 m, ΔFEV1 was +0.11±0.20 L and +0.11±0.30 L, and ΔRV (residual volume) was −0.65±0.90 L and −0.71±0.81 L (all p<0.01). Post hoc analyses showed significant responses for SGRQ, 6MWD and RV in patients with both heterogeneous and homogeneous emphysema.
LVR coil treatment results in significant clinical improvements in patients with severe emphysema, with a good safety profile and sustained results for up to 1 year.
Trial registration number:
PMCID: PMC4215297  PMID: 24891327
Emphysema; Bronchoscopy
3.  Bronchial Thermoplasty – Long Term Safety and Effectiveness in Severe Persistent Asthma 
Bronchial thermoplasty (BT) has previously been shown to improve asthma control out to 2 years in patients with severe persistent asthma.
To assess effectiveness and safety of BT in asthma patients 5 years post therapy.
BT-treated subjects from the Asthma Intervention Research 2 (AIR2) Trial ( NCT01350414) were evaluated annually for 5 years to assess long-term safety of BT and durability of treatment effect. Outcomes assessed post-BT included severe exacerbations, adverse events, healthcare utilization, spirometry data, and high resolution computed tomography (HRCT) scans.
162/190 BT-treated subjects (85.3%) from the AIR2 Trial completed 5 years of follow-up. The proportion of subjects experiencing severe exacerbations and Emergency Room visits, and the rates of events in each of years 1 to 5 remained low and were less than those observed in the 12 months prior to BT treatment (average 5 year reduction in proportions: 44% for exacerbations and 78% for ER visits). Respiratory adverse events and respiratory-related hospitalizations remained unchanged in Years 2 through 5 as compared to the first year after BT. Pre-BD FEV1 values remained stable between years 1 and 5 after BT, despite a 17% reduction in average daily inhaled corticosteroid dose. HRCT scans from baseline to 5 years after BT showed no structural abnormalities that could be attributed to BT.
These data demonstrate the 5-year durability of the benefits of BT with regard to both asthma control (based on maintained reduction in severe exacerbations and ER visits for respiratory symptoms) and safety. BT has become an important addition to our treatment armamentarium and should be considered for patients with severe persistent asthma who remain symptomatic despite taking ICS (inhaled corticosteroids) and LABA (long-acting-β2-agonists).
PMCID: PMC4114404  PMID: 23998657
Bronchial thermoplasty; asthma; Bronchoscopic procedure; Alair System; asthma exacerbation
4.  Critical role of aldehydes in cigarette smoke-induced acute airway inflammation 
Respiratory Research  2013;14(1):45.
Cigarette smoking (CS) is the most important risk factor for COPD, which is associated with neutrophilic airway inflammation. We hypothesize, that highly reactive aldehydes are critical for CS-induced neutrophilic airway inflammation.
BALB/c mice were exposed to CS, water filtered CS (WF-CS) or air for 5 days. Levels of total particulate matter (TPM) and aldehydes in CS and WF-CS were measured. Six hours after the last exposure, inflammatory cells and cytokine levels were measured in lung tissue and bronchoalveolar lavage fluid (BALF). Furthermore, Beas-2b bronchial epithelial cells were exposed to CS extract (CSE) or WF-CS extract (WF-CSE) in the absence or presence of the aldehyde acrolein and IL-8 production was measured after 24 hrs.
Compared to CS, in WF-CS strongly decreased (CS; 271.1 ± 41.5 μM, WF-CS; 58.5 ± 8.2 μM) levels of aldehydes were present whereas levels of TPM were only slightly reduced (CS; 20.78 ± 0.59 mg, WF-CS; 16.38 ± 0.36 mg). The numbers of mononuclear cells in BALF (p<0.01) and lung tissue (p<0.01) were significantly increased in the CS- and WF-CS-exposed mice compared to air control mice. Interestingly, the numbers of neutrophils (p<0.001) in BALF and neutrophils and eosinophils (p<0.05) in lung tissue were significantly increased in the CS-exposed but not in WF-CS-exposed mice as compared to air control mice. Levels of the neutrophil and eosinophil chemoattractants KC, MCP-1, MIP-1α and IL-5 were all significantly increased in lung tissue from CS-exposed mice compared to both WF-CS-exposed and air control mice. Interestingly, depletion of aldehydes in WF-CS extract significantly reduced IL-8 production in Beas-2b as compared to CSE, which could be restored by the aldehyde acrolein.
Aldehydes present in CS play a critical role in inflammatory cytokine production and neutrophilic- but not mononuclear airway inflammation.
PMCID: PMC3671961  PMID: 23594194
Cigarette smoke; Aldehydes; Mouse model; Airway inflammation; COPD
5.  Role of aberrant metalloproteinase activity in the pro-inflammatory phenotype of bronchial epithelium in COPD 
Respiratory Research  2011;12(1):110.
Cigarette smoke, the major risk factor for COPD, is known to activate matrix metalloproteinases in airway epithelium. We investigated whether metalloproteinases, particularly A Disintegrin and Metalloproteinase (ADAM)17, contribute to increased pro-inflammatory epithelial responses with respect to the release of IL-8 and TGF-α, cytokines implicated in COPD pathogenesis.
We studied the effects of cigarette smoke extract (CSE) and metalloproteinase inhibitors on TGF-α and IL-8 release in primary bronchial epithelial cells (PBECs) from COPD patients, healthy smokers and non-smokers.
We observed that TGF-α was mainly shed by ADAM17 in PBECs from all groups. Interestingly, IL-8 production occurred independently from ADAM17 and TGF-α shedding, but was significantly inhibited by broad-spectrum metalloproteinase inhibitor TAPI-2. CSE did not induce ADAM17-dependent TGF-α shedding, while it slightly augmented the production of IL-8. This was accompanied by reduced endogenous inhibitor of metalloproteinase (TIMP)-3 levels, suggesting that CSE does not directly but rather indirectly alter activity of ADAM17 through the regulation of its endogenous inhibitor. Furthermore, whereas baseline TGF-α shedding was lower in COPD PBECs, the early release of IL-8 (likely due to its shedding) was higher in PBECs from COPD than healthy smokers. Importantly, this was accompanied by lower TIMP-2 levels in COPD PBECs, while baseline TIMP-3 levels were similar between groups.
Our data indicate that IL-8 secretion is regulated independently from ADAM17 activity and TGF-α shedding and that particularly its early release is differentially regulated in PBECs from COPD and healthy smokers. Since TIMP-2-sensitive metalloproteinases could potentially contribute to IL-8 release, these may be interesting targets to further investigate novel therapeutic strategies in COPD.
PMCID: PMC3182910  PMID: 21861887
Cigarette smoke; ADAM17; IL-8; TGF-α; TIMP-2
6.  Design of the exhale airway stents for emphysema (EASE) trial: an endoscopic procedure for reducing hyperinflation 
Airway Bypass is a catheter-based, bronchoscopic procedure in which new passageways are created that bypass the collapsed airways, enabling trapped air to exit the lungs. The Exhale Airway Stents for Emphysema (EASE) Trial was designed to investigate whether Exhale® Drug-Eluting Stents, placed in new passageways in the lungs, can improve pulmonary function and reduce breathlessness in severely hyperinflated, homogeneous emphysema patients (NCT00391612).
The multi-center, randomized, double-blind, sham-controlled trial design was posted on in October 2006. Because Bayesian statistics are used for the analysis, the proposed enrollment ranged from 225 up to 450 subjects at up to 45 institutions. Inclusion criteria are: high resolution CT scan with evidence of homogeneous emphysema, post-bronchodilator pulmonary function tests showing: a ratio of FEV1/FVC < 70%, FEV1≤50% of predicted or FEV1 < 1 liter, RV/TLC≥0.65 at screening, marked dyspnea score ≥2 on the modified Medical Research Council scale of 0-4, a smoking history of at least 20 pack years and stopped smoking for at least 8 weeks prior to enrollment. Following 16 to 20 supervised pulmonary rehabilitation sessions, subjects were randomized 2:1 to receive either a treatment (Exhale® Drug-Eluting Stent) or a sham bronchoscopy. A responder analysis will evaluate the co-primary endpoints of an FVC improvement ≥12% of the patient baseline value and modified Medical Research Council dyspnea scale improvement (reduction) ≥1 point at the 6-month follow-up visit.
If through the EASE Trial, Airway Bypass is shown to improve pulmonary function and reduce dyspnea while demonstrating an acceptable safety profile, then homogeneous patients will have a minimally invasive treatment option with meaningful clinical benefit.
Trial Registration NCT00391612
PMCID: PMC3024306  PMID: 21214899
7.  Mitochondrial Localization and Function of Heme Oxygenase-1 in Cigarette Smoke–Induced Cell Death 
Cigarette smoke–induced apoptosis and necrosis contribute to the pathogenesis of chronic obstructive pulmonary disease. The induction of heme oxygenase-1 provides cytoprotection against oxidative stress, and may protect in smoking-related disease. Since mitochondria regulate cellular death, we examined the functional expression and mitochondrial localization of heme oxygenase-1 in pulmonary epithelial cells exposed to cigarette smoke extract (CSE), and its role in modulating cell death. Heme oxygenase-1 expression increased dramatically in cytosolic and mitochondrial fractions of human alveolar (A549), or bronchial epithelial cells (Beas-2b) exposed to either hemin, lipopolysaccharide, or CSE. Mitochondrial localization of heme oxygenase-1 was also observed in a primary culture of human small airway epithelial cells. Furthermore, heme oxygenase activity increased dramatically in mitochondrial fractions, and in whole cell extracts of Beas-2b after exposure to hemin and CSE. The mitochondrial localization of heme oxygenase-1 in Beas-2b was confirmed using immunogold-electron microscopy and immunofluorescence labeling on confocal laser microscopy. CSE caused loss of cellular ATP and rapid depolarization of mitochondrial membrane potential. Apoptosis occurred in Beas-2b at low concentrations of cigarette smoke extract, whereas necrosis occurred at high concentrations. Overexpression of heme oxygenase-1 inhibited CSE-induced Beas-2b cell death and preserved cellular ATP levels. Finally, heme oxygenase-1 mRNA expression was elevated in the lungs of mice chronically exposed to cigarette smoke. We demonstrate the functional compartmentalization of heme oxygenase-1 in the mitochondria of lung epithelial cells, and its potential role in defense against mitochondria-mediated cell death during CSE exposure.
PMCID: PMC1899328  PMID: 17079780
cigarette smoke; COPD; heme oxygenase-1; mitochondria
8.  Heme oxygenase-1 prevents smoke induced B-cell infiltrates: a role for regulatory T cells? 
Respiratory Research  2008;9(1):17.
Smoking is the most important cause for the development of COPD. Since not all smokers develop COPD, it is obvious that other factors must be involved in disease development. We hypothesize that heme oxygenase-1 (HO-1), a protective enzyme against oxidative stress and inflammation, is insufficiently upregulated in COPD.
The effects of HO-1 modulation on cigarette smoke induced inflammation and emphysema were tested in a smoking mouse model.
Mice were either exposed or sham exposed to cigarette smoke exposure for 20 weeks. Cobalt protoporphyrin or tin protoporphyrin was injected during this period to induce or inhibit HO-1 activity, respectively. Afterwards, emphysema development, levels of inflammatory cells and cytokines, and the presence of B-cell infiltrates in lung tissue were analyzed.
Smoke exposure induced emphysema and increased the numbers of inflammatory cells and numbers of B-cell infiltrates, as well as the levels of inflammatory cytokines in lung tissue. HO-1 modulation had no effects on smoke induced emphysema development, or the increases in neutrophils and macrophages and inflammatory cytokines. Interestingly, HO-1 induction prevented the development of smoke induced B-cell infiltrates and increased the levels of CD4+CD25+ T cells and Foxp3 positive cells in the lungs. Additionally, the CD4+CD25+ T cells correlated positively with the number of Foxp3 positive cells in lung tissue, indicating that these cells were regulatory T cells.
These results support the concept that HO-1 expression influences regulatory T cells and indicates that this mechanism is involved in the suppression of smoke induced B-cell infiltrates. The translation of this interaction to human COPD should now be pursued.
PMCID: PMC2254411  PMID: 18252008
9.  Heme oxygenase-1 and carbon monoxide in pulmonary medicine 
Respiratory Research  2003;4(1):7.
Heme oxygenase-1 (HO-1), an inducible stress protein, confers cytoprotection against oxidative stress in vitro and in vivo. In addition to its physiological role in heme degradation, HO-1 may influence a number of cellular processes, including growth, inflammation, and apoptosis. By virtue of anti-inflammatory effects, HO-1 limits tissue damage in response to proinflammatory stimuli and prevents allograft rejection after transplantation. The transcriptional upregulation of HO-1 responds to many agents, such as hypoxia, bacterial lipopolysaccharide, and reactive oxygen/nitrogen species. HO-1 and its constitutively expressed isozyme, heme oxygenase-2, catalyze the rate-limiting step in the conversion of heme to its metabolites, bilirubin IXα, ferrous iron, and carbon monoxide (CO). The mechanisms by which HO-1 provides protection most likely involve its enzymatic reaction products. Remarkably, administration of CO at low concentrations can substitute for HO-1 with respect to anti-inflammatory and anti-apoptotic effects, suggesting a role for CO as a key mediator of HO-1 function. Chronic, low-level, exogenous exposure to CO from cigarette smoking contributes to the importance of CO in pulmonary medicine. The implications of the HO-1/CO system in pulmonary diseases will be discussed in this review, with an emphasis on inflammatory states.
PMCID: PMC193681  PMID: 12964953
carbon monoxide; heme oxygenase-1; lung disease
10.  Long-term follow-up after bronchoscopic lung volume reduction treatment with coils in patients with severe emphysema 
Respirology (Carlton, Vic.)  2014;20(2):319-326.
Background and objective
Bronchoscopic lung volume reduction coil (LVR-coil) treatment has been shown to be safe and clinically effective in patients with severe emphysema in the short term; however, long-term safety and effectiveness has not been evaluated. The aim of this study was to investigate the long-term safety and effectiveness of LVR-coil treatment in patients with severe emphysema.
Thirty-eight patients with severe emphysema (median age is 59 years, forced expiratory volume in 1 s is 27% predicted) who were treated in LVR-coil clinical trials were invited for a voluntary annual visit. Safety was evaluated by chest X-ray and recording of adverse events and by efficacy by pulmonary function testing, 6-min walk distance (6MWD) and questionnaires.
Thirty-five patients visited the hospital 1 year, 27 patients 2 years and 22 patients 3 years following coil placement. No coil migrations were observed on X-rays. At 1-year follow-up, all clinical outcomes significantly improved compared with baseline. At 2 years, residual volume % pred, modified Medical Research Council (mMRC) and the SGRQ score were still significantly improved. At 3 years, a significant improvement in mMRC score remained, with 40% of the patients reaching the 6MWD minimal important difference, and 59% for the St George's Respiratory Questionnaire (SGRQ) minimal important difference.
Follow-up of the patients treated with LVR-coils in our pilot studies showed that the coil treatment is safe with no late pneumothoraces, coil migrations or unexpected adverse events. Clinical benefit gradually declines over time; at 3 years post-treatment, around 50% of the patients maintained improvement in 6MWD, SGRQ and mMRC.
PMCID: PMC4321042  PMID: 25418910
bronchoscopy and interventional technique; clinical respiratory medicine; coil; emphysema; long-term follow-up

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