Roberto Marchese

Association between reduced bronchodilatory effect of deep inspiration and loss of alveolar attachments

BackgroundWe have previously shown that the bronchodilatory effect of deep inspiration is attenuated in individuals with COPD. This study was designed to investigate whether the impairment in this effect is associated with loss of alveolar attachments.MethodsWe measured deep inspiration (DI)-induced bronchodilation in 15 individuals with and without COPD (67 ± 2.2 yrs of age, mean ± SEM) undergoing lobar resection for peripheral pulmonary nodule. Prior to surgery, we measured TLCO and determined the bronchodilatory effect of deep inspiration after constricting the airways with methacholine. The number of destroyed alveolar attachments, as well as airway wall area and airway smooth muscle area, were determined in tumor-free, peripheral lung tissue.ResultsThe bronchodilatory effect of deep inspiration correlated inversely with the % destroyed attachments (r = -0.51, p = 0.05) and directly with the airway smooth muscle area (r = 0.59, p = 0.03), but not with the total wall area (r = 0.39, p = 0.15).ConclusionWe postulate that attenuation of airway stretch due to loss of alveolar attachments contributes to the loss of the bronchodilatory effect of lung inflation in COPD.

Fully Covered Self-Expandable Metal Stent in Tracheobronchial Disorders: Clinical Experience

Background: The third-generation fully covered self-expandable metallic stent (SEMS) has been developed to solve the problems of difficult removal and in-stent granuloma formation related to the uncovered or partially covered type. There are few written reports about the performance of this type of stents with early encouraging results. Objectives: To report and analyse our experience with the Silmet® stent in the management of malignant and benign tracheobronchial disorders. Methods: We retrospectively reviewed medical records of patients who underwent fully covered SEMS Silmet placement at the Interventional Pulmonology Unit, La Maddalena Cancer Center, Palermo, Italy, between May 2010 and August 2013. Results: Stents were placed in 52 patients with malignant (n = 49) and benign airway obstruction (n = 2) and broncho-oesophageal fistula (n = 1). SEMSs were inserted into the trachea (n = 19), the main bronchi (n = 21) and the peripheral bronchi (n = 31). Besides 1 procedural dislocation, the deployment was successful in all patients with an immediate significant improvement of symptoms (Barthel Index p < 0.001; Medical Research Council score p < 0.001). A radiographic improvement was detected in 48% of patients. The mean follow-up duration was 119 ± 120 days (range 22-549 days). Complications observed were: migration (7.6%), tumour overgrowth (15%), infections (5.7%), granulation tissue formation (3.8%) and mucus plug (3.8%). Conclusions: The Silmet stent is effective, safe and simple to implant and remove. We suggest its use in cases of tight stenoses, in the treatment of small- to medium-caliber airways or in cases of tortuous airways.

Tracheal Stent to Repair Tracheal Laceration After a Double-Lumen Intubation

A 59-year-old woman was referred for a diagnostic video thoracoscopy under general anesthesia. At the end of the procedure, the patient presented with subcutaneous emphysema and cyanosis, abdominal distension, and bradycardia. A rigid bronchoscopy showed a longitudinal laceration in the pars membranacea of the trachea. A tracheal silicon stent was positioned on an emergency basis. She was intubated, positioning the tracheal tube cuff distal of the stent under bronchoscopic vision. A computed tomographic scan performed immediately after the procedure showed left pneumothorax, pneumoperitoneum, pneumopericardium, and diffuse subcutaneous emphysema. The subsequent course of the patient was uneventful. The patient was discharged home on postoperative day 4. After 1 year, the stent was removed with the evidence of complete trachel healing.

Functional characterization of a novel 3D model of the epithelial-mesenchymal trophic unit

ABSTRACT Background/Aim: Epithelial-mesenchymal communication plays a key role in tissue homeostasis and abnormal signaling contributes to chronic airways disease such as COPD. Most in vitro models are limited in complexity and poorly represent this epithelial-mesenchymal trophic unit. We postulated that cellular outgrowth from bronchial tissue would enable development of a mucosal structure that recapitulates better in vivo tissue architecture. Materials and Methods: Bronchial tissue was embedded in Matrigel and outgrowth cultures monitored using time-lapse microscopy, electrical resistance, light and electron microscopy. Cultures were challenged repetitively with cigarette smoke extract (CSE). Results: The outgrowths formed as a multicellular sheet with motile cilia becoming evident as the Matrigel was remodeled to provide an air interface; cultures were viable for more than one year. Immunofluorescence and electron microscopy (EM) identified an upper layer of mucociliary epithelium and a lower layer of highly organized extracellular matrix (ECM) interspersed with fibroblastic cells separated by a basement membrane. EM analysis of the mucosal construct after repetitive exposure to CSE revealed epithelial damage, loss of cilia, and ECM remodeling, as occurs in vivo. Conclusions: We have developed a robust bronchial mucosal model. The structural changes observed following CSE exposure suggest the model should have utility for drug discovery and preclinical testing, especially those targeting airway remodeling.

IL-17A-associated IKK-α signaling induced TSLP production in epithelial cells of COPD patients

Thymic stromal lymphopoietin (TSLP) is a cytokine expressed in the epithelium, involved in the pathogenesis of chronic disease. IL-17A regulates airway inflammation, oxidative stress, and reduction of steroid sensitivity in chronic obstructive pulmonary disease (COPD). TSLP and IL-17A were measured in induced sputum supernatants (ISs) from healthy controls (HC), healthy smokers (HS), and COPD patients by enzyme-linked immunosorbent assay. Human bronchial epithelial cell line (16HBE) and normal bronchial epithelial cells were stimulated with rhIL-17A or ISs from COPD patients to evaluate TSLP protein and mRNA expression. The effects of the depletion of IL-17A in ISs, an anticholinergic drug, and the silencing of inhibitor kappa kinase alpha (IKKα) on TSLP production were evaluated in 16HBE cells. Coimmunoprecipitation of acetyl-histone H3(Lys14)/IKKα was evaluated in 16HBE cells treated with rhIL-17A and in the presence of the drug. TSLP and IL-17A levels were higher in ISs from COPD patients and HS compared with HC. TSLP protein and mRNA increased in 16HBE cells and in normal bronchial epithelial cells stimulated with ISs from COPD patients compared with ISs from HC and untreated cells. IKKα silencing reduced TSLP production in 16HBE cells stimulated with rhIL-17A and ISs from COPD patients. RhIL-17A increased the IKKα/acetyl-histone H3 immunoprecipitation in 16HBE cells. The anticholinergic drug affects TSLP protein and mRNA levels in bronchial epithelial cells treated with rhIL-17A or with ISs from COPD patients, and IKKα mediated acetyl-histone H3(Lys14). IL-17A/IKKα signaling induced the mechanism of chromatin remodeling associated with acetyl-histone H3(Lys14) and TSLP production in bronchial epithelial cells. Anticholinergic drugs might target TSLP derived from epithelial cells during the treatment of COPD.Lung disease: inflammatory proteins implicated in chronic obstructive pulmonary diseaseTwo proteins involved in the maturation of immune cells contribute to the inflammation responsible for chronic obstructive pulmonary disease (COPD) and could thus provide promising drug targets for future therapies. Mirella Profita from the Institute of Biomedicine and Molecular Immunology “Alberto Monroy” in Palermo, Italy, and colleagues showed that lung secretions from people with COPD and those who smoke cigarettes have higher levels of interleukin-17A and thymic stromal lymphopoietin (TSLP), two proteins associated with inflammatory immune responses, than samples from healthy non-smokers. In bronchial epithelial cell lines, the researchers showed that interleukin-17A induces the expression of TSLP, whereas an existing bronchodilatator anticholinerc drug, usually used to treat COPD, reduces TSLP levels. The authors suggest that these drugs could complement existing COPD therapies to block proinflammatory proteins.

An ex vivo model of the human airways to study the effects of long-term exposure to Space conditions

An innovative 3D model of the human bronchial mucosa, a result of a long- term collaboration with Prof. Davies from the University of Southampton, UK, will be used to study, on board the International Space Station (ISS), the chang- es occurring in lungs exposed to the adverse environmental conditions found in Space. Our research group has developed a tissue engineered human airway model, providing a viable alternative to the use of animal models. The bronchial outgrowth offers numerous advantages compared to traditional approaches that use human tissue, including: the morphological analogy with the bronchial mucosa; the possibility to study long-term exposure (several months) to environmental factors (cigarette smoke, respiratory viruses, etc.) being able to analyze eventual changes in the long term; the possibility to add cellular and humoral components of the immune system in order to evaluate their effects. Recently, our application to the ILSRA 2014 solicitation by NASA/ESA, in which we propose to study the effects of prolonged stay on board the ISS on the development and function of human airway cells in our model, was successful and our project was selected. This project will involve several international partners, including, in addition to the University of Palermo and Southampton, the Euro-Mediterranean Institute of Science and Technology (IEMEST, Palermo), the University of Leiden (NL), the University of Galveston (Texas, USA), the Wyle Laboratories (Texas, USA) and NASA itself. The results obtained will be particularly useful in view of exploratory missions of our solar system planned in the near future. To verify the resilience of the model to the extreme environmental conditions on board the vectors that transport the samples to the ISS, and therefore collect essential data prior to the flight experiments, differentiated outgrowths obtained from healthy patients were exposed for up to 1 week to the following stress conditions: withdrawal of growth medium, reduced culture temperature (10 and 20°C), absence of CO2, intense rolling and shaking motions. TER values were measured 1 week prior to 1 week after the exposures to evaluate the effects of these stimuli. The data obtained show that even though the stimuli determined a slight degree of tissue alteration (reduction of TER) during exposure, the outgrowths promptly recovered their origi- nal structure and function.