Expression of human Interferon Regulatory Factor 3 (IRF-3) in alveolar macrophages relates to clinical and functional traits in COPD.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a frequent cause of morbidity and mortality. Dysregulated and enhanced immune-inflammatory responses have been described in COPD. Recent data showed impaired immune responses and, in particular, of interferon (IFNs) signaling pathway in these patients. AIM: To evaluate in peripheral lung of COPD patients, the expression of some of the less investigated key components of the innate immune responses leading to IFN productions including: IFN-receptors (IFNAR1/IFNAR2), IRF-3 and MDA-5. Correlations with clinical traits and with the inflammatory cell profile have been assessed. METHODS: Lung specimens were collected from 58 subjects undergoing thoracic surgery: 22 COPD patients, 21 smokers with normal lung function (SC) and 15 non-smoker controls (nSC). The expression of IFNAR1, IFNAR2, IRF-3 and MDA-5, of eosinophils and activated NK cells (NKp46+) were quantified in the peripheral lung by immunohistochemistry. RESULTS: A significant increase of IRF-3 + alveolar macrophages were observed in COPD and SC compared with nSC subjects. However, in COPD patients, the lower the levels of IRF-3 + alveolar macrophages the lower the FEV1 and the higher the exacerbation rate. The presence of chronic bronchitis (CB) was also associated with low levels of IRF-3 + alveolar macrophages. NKp46 + cells, but not eosinophils, were increased in COPD patients compared to nSC patients (p < 0.0001). CONCLUSIONS: Smoking is associated with higher levels of innate immune response as showed by higher levels of IRF-3 + alveolar macrophages and NKp46 + cells. In COPD, exacerbation rates, severe airflow obstruction and CB were associated with lower levels of IRF-3 expression, suggesting that innate immune responses characterize specific clinical traits of the disease.

Thymic Stromal Lymphopoietin and Tezepelumab in Airway Diseases: From Physiological Role to Target Therapy.

Thymic stromal lymphopoietin (TSLP), is a protein belonging to a class of epithelial cytokines commonly called alarmins, which also includes IL-25 and IL-33. Functionally, TSLP is a key player in the immune response to environmental insults, initiating a number of downstream inflammatory pathways. TSLP performs its role by binding to a high-affinity heteromeric complex composed of the thymic stromal lymphopoietin receptor (TSLPR) chain and IL-7Rα. In recent years, the important role of proinflammatory cytokines in the etiopathogenesis of various chronic diseases such as asthma, chronic rhinosinusitis with nasal polyposis (CRSwNP), chronic obstructive pulmonary diseases (COPDs), and chronic spontaneous urticaria has been studied. Although alarmins have been found to be mainly implicated in the mechanisms of type 2 inflammation, studies on monoclonal antibodies against TSLP demonstrate partial efficacy even in patients whose inflammation is not definable as T2 and the so-called low T2. Tezepelumab is a human anti-TSLP antibody that prevents TSLP-TSLPR interactions. Several clinical trials are evaluating the safety and efficacy of Tezepelumab in various inflammatory disorders. In this review, we will highlight major recent advances in understanding the functional role of TSLP, its involvement in Th2-related diseases, and its suitability as a target for biological therapies.

Immune induction of airway remodeling.

Airway remodeling is accepted to be a determining component within the natural history of asthma. It is a phenomenon characterized by changes in the airways structures that marches in parallel with and can be influenced by airway inflammation, floating at the interface between both natural and adaptive immunity and physical and mechanical cells behavior. In this review we aimed to highlight the comprehensive, yet not exhaustive, evidences of how immune cells induce, regulate and adapt to the recognized markers of airway remodeling. Mucous cell hyperplasia, epithelial dysfunction and mesenchymal transition, extracellular matrix protein synthesis and restructuration, fibroblast to myofibroblast transition, airway smooth muscle proliferation, bioactive and contractile properties, and vascular remodeling encompass complex physiopathological mechanisms that can be induced, suppressed or regulated by different cellular and molecular pathways. Growth factors, cytokines, chemokines and adhesion molecules expressed or derived either from the immune network of cells infiltrating the asthmatic airways and involving T helper lymphocytes, immune lymphoid cells, dendritic cells, eosinophils, neutrophils, mast cells or by the structural components such as epithelial cells, fibroblasts, myocytes, airway smooth muscle cells concur with protein cellular matrix component and metalloproteases in modifying the airway structure in a detrimental way. The consequences in lung function decline, fixed airway obstruction and clinical severity of the disease suggest the possibility of identify among the immune molecular pathway of remodeling some biological parameters or signal pathway to be either a good tracer for monitoring the disease evolution or a target for hypothetical phenotypes and endotypes. In the era of personalized medicine, a biomarker of remodeling might predict a response to small-molecule inhibitors or biologicals potentially targeting a fundamental aspect of asthma pathogenesis that impacts on the low responsiveness to airway inflammation directed treatments.

One year of mepolizumab. Efficacy and safety in real-life in Italy.

BACKGROUND: Severe asthma is a disease with a heavy socio-economic burden and a relevant impact on the life of patients. Mepolizumab (MEP) was recently introduced in practice. The previous data were favourable as efficacy and safety are concerned. Nowadays, we can report the clinical data after more than one year of use of MEP in the real-life setting. OBJECTIVE: To evaluate the efficacy and safety of MEP in a real life framework, mainly concerning asthma exacerbations, steroid dependence, effects on respiratory function and adverse events. METHODS: This retrospective analysis was performed on 138 patients, treated with MEP for at least 12 months, and referred to eleven severe asthma clinics in Italy. All patients met the criteria for severe uncontrolled asthma according to ATS/ERS guidelines and prescribing MEP conditions according to the Italian Drug Agency (AIFA). RESULTS: We could observe 138 patients (78 female, age 58 ±â€¯10 years). The average age of onset of asthma was 34 ±â€¯16 years. The blood eosinophil count decreased from 822 ±â€¯491/µL at baseline to 117 ±â€¯96/µL (p < .0001) after 12 months of therapy. Exacerbations decreased from 3.8/year to 0.7/year (-81%; p < .0001). Steroid-dependent patients before MEP (80%) with a daily dose of 10.1 ±â€¯9.4 mg prednisone decrease at 28% after 12 months with a mean of 2.0 ±â€¯4.2 mg/day (p < .0001). The occurrence of adverse events was overall low. CONCLUSIONS & CLINICAL RELEVANCE: In this real-life setting, MEP confirmed its efficacy and safety profile, already shown in clinical trials. This was apparent concerning exacerbation rate, systemic steroids intake and safety.

Molecular diagnosis and precision medicine in allergy management.

Precision medicine (PM) can be defined as a structural model aimed at customizing healthcare, with medical decisions/products tailored on an individual patient at a highly detailed level. In this sense, allergy diagnostics based on molecular allergen components allows to accurately define the patient's IgE repertoire. The availability of highly specialized singleplexed and multiplexed platforms support allergists with an advanced diagnostic armamentarium. The therapeutic intervention, driven by the standard diagnostic approach, but further supported by these innovative tools may result, for instance, in a more appropriate prescription of allergen immunotherapy (AIT). Also, the phenotyping of patients, which may have relevant effects on the treatment strategy, could be take advantage by the molecular allergy diagnosis.

Biomarkers and severe asthma: a critical appraisal.

Severe asthma (SA) is a clinically and etiologically heterogeneous respiratory disease which affects among 5-10 % of asthmatic patients. Despite high-dose therapy, a large patients percentage is not fully controlled and has a poor quality of life. In this review, we describe the biomarkers actually known in scientific literature and used in clinical practice for SA assessment and management: neutrophils, eosinophils, periostin, fractional exhaled nitric oxide, exhaled breath condensate and galectins. Moreover, we give an overview on clinical and biological features characterizing severe asthma, paying special attention to the potential use of these ones as reliable markers. We finally underline the need to define different biomarkers panels to select patients affected by severe asthma for specific and personalized therapeutic approach.

The administration of a polyvalent mechanical bacterial lysate in elderly patients with COPD results in serological signs of an efficient immune response associated with a reduced number of acute episodes.

The administration of a polyvalent mechanical bacterial lysate (PMBL) in elderly patients with COPD has been shown to reduce the number of exacerbation. This is largely related to the involvement of cells belonging to the innate and the adaptive immune system (including dendritic cells, granulocytes, T and B lymphocytes and NK cells) that actively cooperate inducing the production of specific opsonizing antibodies directed to the antigens of PMBL. We have evaluated the production of antibodies directed to respiratory and systemic pathogens in a group of elderly COPD patients, recruited in a clinical trial, ancillary to a larger multicenter double blind, placebo-controlled, parallel-designed clinical trial in which patients were randomized to daily receive either PMBL or placebo. The treated group not only experienced a reduced number of seroconversion, but also, better controlled the number of infectious episodes and COPD exacerbations. It was thus evident that the administration of PMBL resulted not only effective in inducing the secretion of specific antibodies, but also effective in reducing the infectious episodes trough the potentiation of the antibody-mediated arm of the immune response.

Moderate asthma: burden, mechanisms and therapeutic perspectives.

PURPOSE OF REVIEW: Global Initiative for Asthma (GINA) document provides a classification of asthma severity according with the current level of treatment required to achieve diseases control and underlines the limitations of this approach. In this review, we will provide an overview of recent investigations that have analyzed clinical and molecular features of moderate asthma. RECENT FINDINGS: Moderate asthma is heterogeneous in terms of response to inhaled treatment and pathogenetic mechanisms underlying the clinical features. Analysis of inflammatory pathways in patients who do not achieve disease remission allows identification of patient subgroups that may benefit from specific biological treatments. SUMMARY: Scientific progress makes increasingly clear that there are biological mechanisms capable of identifying and justifying the degree of severity of asthma. The identification of these, combined with the development of new pharmacological treatments, will be the cornerstones of improving the management of asthma in its degrees of severity.

Long-Term Efficacy of Mepolizumab at 3 Years in Patients with Severe Asthma: Comparison with Clinical Trials and Super Responders.

The efficacy mepolizumab in severe asthmatic patients is proven in the literature. Primarily to study the effect of mepolizumab on exacerbations, steroid dependence, and the continuation of efficacy in the long term. Secondarily to evaluate the effect of the drug on nasal polyps. Analyzing data from SANI (Severe Asthma Network Italy) clinics, we observed severe asthmatic patients treated with mepolizumab 100 mg/4 weeks, for a period of 3 years. 157 patients were observed. Exacerbations were reduced from the first year (-84.6%) and progressively to 90 and 95% in the second and third ones. Steroid-dependent patients decreased from 54% to 21% and subsequently to 11% in the second year and 6% in the third year. Patients with concomitant nasal polyps, assessed by SNOT-22, showed a 49% reduction in value from baseline to the third year. The study demonstrated the long-term efficacy of mepolizumab in a real-life setting.

Nasal cytology as a reliable non-invasive procedure to phenotype patients with type 2 chronic rhinosinusitis with nasal polyps.

Background: The identification of type-2 inflammation in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) acquires a crucial role in the endotypization needed for selecting patients for biological drugs targeting type-2 inflammation: to date, the parameters used include systemic and histological biomarkers. The aim of this study was to investigate whether nasal cytology could identify type-2 inflammation in patients with CRSwNP. Methodology: Thirty-three consecutive patients with CRSwNP underwent nasal cytology sampling at the level of the lower nasal turbinate, and of the polypoid tissue, and surgical polyp tissue sample was collected. The cellularity of the 3 collected samples were compared. Results: Mean nasal polyp tissue, nasal polyps cytology and inferior turbinate cytology eosinophils counts were 43.7 ± 39.6 cells/HPF, 32.8 ± 44.7 cells/HPF and 27.6 ± 58.0 cells/HPF respectively with inferior turbinate cytology eosinophils significantly lower than nasal polyp tissue count (p = 0.007). Both mean nasal polyps cytology eosinophils and mean inferior turbinate cytology eosinophils were significantly higher in patients with type-2 CRSwNP (52.5 ± 67.0 cells/HPF vs 12.2 ± 17.3 cells/HPF, p = 0.012, and 32.0 ± 62.1 cells/HPF vs 2.9 ± 2.9 cells/HPF, p = 0.020 respectively). Conclusions: Nasal cytology is suitable tool for assessing local biomarkers of type-2 inflammation in CRSwNP.

In Vitro Reduction of Interleukin-8 Response to Enterococcus faecalis by Escherichia coli Strains Isolated from the Same Polymicrobial Urines.

Urinary tract infections are often polymicrobial and are mainly due to uropathogenic Escherichia coli (UPEC). We previously demonstrated a link among clinical fluoroquinolone susceptible E. coli reducing in vitro urothelial interleukin-8 (CXCL8) induced by E. coli K-12, polymicrobial cystitis, and pyuria absence. Here, we evaluated whether fifteen clinical fluoroquinolone susceptible UPEC were able to reduce CXCL8 induced by Enterococcus faecalis that had been isolated from the same mixed urines, other than CXCL8 induced by E. coli K-12. We also evaluated the connection between fluoroquinolone susceptibility and pathogenicity by evaluating the immune modulation of isogenic gyrA, a mutant UPEC resistant to ciprofloxacin. Using the 5637 bladder epithelial cell line, we observed that lower CXCL8 induced the most UPEC isolates than K-12 and the corresponding E. faecalis. During coinfections of UPEC/K-12 and UPEC/E. faecalis, we observed lower CXCL8 than during infections caused by K-12 and E. faecalis alone. UPEC strains showed host-pathogen and pathogen-pathogen interaction, which in part explained their persistence in the human urinary tract and coinfections, respectively. Mutant UPEC showed lower modulating activity with respect to the wildtypes, confirming the connection between acquired fluoroquinolone resistance and the decrease of innate microbial properties.

Quick Olfactory Sniffin' Sticks Test (Q-Sticks) for the detection of smell disorders in COVID-19 patients.

BACKGROUND: Coronavirus disease (COVID-19) infection represents a worldwide critical health burden from the sanitary perspective. This disease's symptoms range from a mild flu-like form to a severe life-threatening respiratory disease and respiratory failure. Several patients, however, remain paucisymptomatic. Among the symptoms that seem relevant are the changes in taste and smell, regardless of the disease's severity. METHODS: Data from patients affected by COVID-19 infection, hospitalized from 15 to 29 April, 2020, were analyzed. Questionnaires about smell, taste, and nasal function were administered to all, and a proportion also received the Quick olfactory Sniffin' Sticks Test (q-Sticks) to objectivate the presence of anosmia or hyposmia. The results of instruments and Q-Sticks were then compared. RESULTS: Thirty-seven patients (20 males, 54.1%), with a mean age 0f 69.19 years (SD = 17.96; median 76, IQR: 63-82) were evaluated. Among the patients, 8 (22%) were asymptomatic. Out of the remaining 29 patients, 28 (97%) had fever, 19 (66%) asthenia, 11 (38%) dry cough, 10 (34%) dyspnea, and 6 (21%) gastroenteric symptoms. The q-Sticks test was performed on 27 patients and showed that 6 with anosmia, and 16 patients had hyposmia, where only 5 (14%) patients complained of loss of smell by conducting the questionnaires. CONCLUSION: Although olfactory disturbances may be secondary to other factors, a sudden onset of anosmia or hyposmia should be assessed as a possible symptom of COVID-19 infection. The use of questionnaires or anamnestic collection is sometimes not enough, while adding to them a simple test such as the q-Sticks test can provide more accurate and reliable data. A simple, easy-to-perform, and reliable tool (q-Sticks) for olfactory disorders assessment can be administered to identify the real size of anosmia in patients with COVID-19 infection and detect the early stage of infection or paucisymptomatic patients, therefore becoming important to reduce the spreading of the pandemic.

Severe asthma: One disease and multiple definitions.

INTRODUCTION: There is, so far, no universal definition of severe asthma. This definition usually relies on: number of exacerbations, inhaled therapy, need for oral corticosteroids, and respiratory function. The use of such parameters varies in the different definitions used. Thus, according to the parameters chosen, each patient may result in having severe asthma or not. The aim of this study was to evaluate how the choice of a specific definition of severe asthma can change the allocation of patients. METHODS: Data collected from the Severe Asthma Network Italy (SANI) registry were analyzed. All the patients included were then reclassified according to the definitions of U-BIOPRED, NICE, WHO, ATS/ERS, GINA, ENFUMOSA, and TENOR. RESULTS: 540 patients, were extracted from the SANI database. We observed that 462 (86%) met the ATS/ERS criteria as well as the GINA criteria, 259 (48%) the U-Biopred, 222 (41%) the NICE, 125 (23%) the WHO, 313 (58%) the Enfumosa, and 251 (46%) the TENOR criteria. The mean eosinophil value were similar in the ATS/ERS, U-Biopred, and Enfumosa (528, 532 and 516 cells/mcl), higher in WHO and Tenor (567 and 570 cells/mcl) and much higher in the NICE classification (624 cells/mcl). Lung function tests resulted similarly in all groups, with WHO (67%) and ATS/ERS-GINA (73%), respectively, showing the lower and upper mean FEV1 values. CONCLUSIONS: The present observations clearly evidence the heterogeneity in the distribution of patients when different definitions of severe asthma are used. However, the recent definition of severe asthma, provided by the GINA document, is similar to that indicated in 2014 by ATS/ERS, allowing mirror reclassification of the patients examined. This lack of homogeneity could complicate the access to biological therapies. The definition provided by the GINA document, which reflects what suggested by ATS/ERS, could partially overcome the problem.

Plasma Galectin-3 and urine proteomics predict FEV1 improvement in omalizumab-treated patients with severe allergic asthma: Results from the PROXIMA sub-study.

BACKGROUND: Patients with severe allergic asthma (SAA) when treated with omalizumab may exhibit different extent of response. Identifying biomarkers that can predict the extent of treatment effectiveness in patients can be useful in personalizing omalizumab treatment. METHODS: Patients from the longitudinal phase of the PROXIMA study were selected for this ancillary study. After 12 months of omalizumab treatment, patients were categorized according to their response to treatment as: "clinical responder" (Asthma Control Questionnaire [ACQ] total score <1 at Month 12 and/or with a reduction in number of exacerbation versus the previous year); "functional responder" (an increment of ≥0.1 L in forced expiratory volume in 1 s [FEV1] at Month 12 versus baseline); and "super responder" (among clinical responders group, who also showed a functional response). Plasma galectin-3 (GAL-3) levels were quantified using a micro titer plate-based enzyme linked immunosorbent assay kit. RESULTS: The Majority of patients (86.36%) in sub-study population were identified as clinical responders. Of the total patients identified as clinical responders, 64.86% were identified as super responders. A statistically significant difference in the baseline plasma GAL-3 levels between responders and non-responders was observed only in the functional responders group (P = 0.0446). Patients with plasma GAL-3 level of ≥11 ng/mL had a greater probability of being a super responder (P = 0.0118) or a functional responder (P = 0.0032). CONCLUSION: Our findings support the use of plasma GAL-3 as a predictive marker to stratify responders and identify super responders and functional responders to omalizumab treatment in patients with severe allergic asthma using less invasive sample like plasma.

Evolving phenotypes to endotypes: is precision medicine achievable in asthma?

Introduction: The development of biologic molecules led to a drastic change in the therapeutic approach to asthma. With the prospect of acting on different pathophysiological mechanisms of the disease, the idea of precision medicine was developed, in which a single molecule is able to modify a specific triggering mechanism. Thus, it seemed limiting to stop at the distinction of patients phenotypes and the concept of endotypes became more relevant in the therapeutic approach.Areas covered: This review deepened the topic of precision medicine through the transition from phenotyping to endotyping. We performed a review of the literature, preferring articles quoted in Medline and published in journals with an impact factor. Results showed that it is fundamental to take into consideration the role of biomarkers and the related therapies currently available for precision medicine.Expert opinion: The possible overlap of patients in different phenotypes requires a more precise classification, which considers endotypization. With the development of biological drugs able to modify and modulate some pathophysiological mechanisms of the disease, the theoretical concept of endotyping becomes practical, allowing the clinician to choose the specific mechanism to 'attack' in order to control the disease.

Efficacy of Benralizumab in severe asthma in real life and focus on nasal polyposis.

INTRODUCTION: Severe asthma occurs in 5-10% of asthmatic patients, with nasal polyposis as one of the most frequent comorbidity. Benralizumab was recently marketed, thus we could analyse its effects in real-life in severe asthma, and compare the effects of the drug in patients with and without polyposis. METHODS: Patients with severe asthma, receiving Benralizumab were enrolled in Italian asthma centres. The efficacy criteria for asthma (exacerbation rate, oral corticosteroid intake, hospitalizations, pulmonary function, exhaled nitric oxide) were evaluated at baseline and after 24 weeks of treatment. Patients were then sub-analysed according to the presence/absence of nasal polyposis. RESULTS: Fifty-nine patients with severe uncontrolled asthma (21 males, age range 32-78) and treated with benralizumab for at least 24 weeks has been evaluated, showing significant improvements in asthma-related outcomes, except for pulmonary function and exhaled nitric oxide. This included a reduction in the sino-nasal outcome-22 score versus baseline of 13.7 points (p = .0037) in the 34 patients with nasal polyposis. Anosmia disappeared in 31% patients (p = .0034). When comparing the groups with and without nasal polyposis, a similar reduction of exacerbations was seen, with a greater reduction of the steroid dependence in patients with polyposis (-72% vs -53%; p < .0001), whereas lung function was significantly more improved (12% vs 34%, p = .0064) without polyposis patients. CONCLUSIONS: Benralizumab, after 6 months of treatment, confirmed its efficacy in severe asthma, and also in nasal polyposis, which is the most frequent comorbidity. The efficacy of Benralizumab in reducing steroid dependence was even higher in patients with polyposis.

Galectin-3: an early predictive biomarker of modulation of airway remodeling in patients with severe asthma treated with omalizumab for 36 months.

BACKGROUND: Bronchial asthma is a heterogeneous disease characterized by three cardinal features: chronic inflammation, variable airflow obstruction, and airway hyperresponsiveness. Asthma has traditionally been defined using nonspecific clinical and physiologic variables that encompass multiple phenotypes and are treated with nonspecific anti-inflammatory therapies. Based on the modulation of airway remodeling after 12 months of anti-immunoglobulin E (IgE) treatment, we identified two phenotypes (omalizumab responder, OR; and non-omalizumab responder, NOR) and performed morphometric analysis of bronchial biopsy specimens. We also found that these two phenotypes were correlated with the presence/absence of galectin-3 (Gal-3) at baseline (i.e., before treatment). The aims of the present study were to investigate the histological and molecular effects of long-term treatment (36 months) with anti-IgE and to analyze the behavior of OR and NOR patients. METHODS: All patients were treated with the monoclonal antibody anti-IgE omalizumab for 36 months. The bronchial biopsy specimens were evaluated using morphometric, eosinophilic, and proteomic analysis (MudPIT). New data were compared with previous data, and unsupervised cluster analysis of protein profiles was performed. RESULTS: After 36 months of treatment with omalizumab, reduction of reticular basement membrane (RBM) thickness was confirmed in OR patients (Gal-3-positive at baseline); similarly, the protein profiles (over 500 proteins identified) revealed that, in the OR group, levels of proteins specifically related to fibrosis and inflammation (e.g., smooth muscle and extracellular matrix proteins (including periostin), Gal-3, and keratins decreased by between 5- and 50-fold. Eosinophil levels were consistent with molecular data and decreased by about tenfold less in ORs and increased by twofold to tenfold more in NORs. This tendency was confirmed (p < 0.05) based on both fold change and DAVE algorithms, thus indicating a clear response to anti-IgE treatment in Gal-3-positive patients. CONCLUSIONS: Our results showed that omalizumab can be considered a disease-modifying treatment in OR. The proteomic signatures confirmed the presence of Gal-3 at baseline to be a biomarker of long-term reduction in bronchial RBM thickness, eosinophilic inflammation, and muscular and fibrotic components in omalizumab-treated patients with severe asthma. Our findings suggest a possible relationship between Gal-3 positivity and improved pulmonary function.

Molecular phenotyping and biomarker development: are we on our way towards targeted therapy for severe asthma?

Although different phenotypes of severe asthma can be identified, all are characterized by common symptoms. Due to their heterogeneity, they exhibit differences in pathogenesis, etiology and clinical responses to therapeutic approaches. The identification of distinct molecular phenotypes to define severe asthmatic patients will allow us to better understand the pathophysiology of the disease and thus to more precisely target the treatment for each patient. To achieve this goal, a systematic search for new, reliable and stable biomarkers specific for each phenotype is essential. This review focuses on the current known molecular phenotypes of severe asthma and highlights the need for biomarkers that could (either alone or in combination) be predictive of the treatment outcome.

CD4(+)CD25(high)CD127(-) regulatory T-cells in COPD: smoke and drugs effect.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a progressive lung disorder characterized by poorly reversible airway obstruction and its pathogenesis remains largely misunderstood. Local changes of regulatory T-cell populations in the lungs of COPD patients have been demonstrated although data concerning their pathologic role are contrasting. The aim of our study was to evaluate the relative percentage of regulatory T-cells in the peripheral blood of current and former smoker subjects, affected or not by COPD. Furthermore, the effect of different concentrations of budesonide and formoterol, on regulatory T-cells has been investigated. METHODS: T regulatory lymphocytes were isolated and assessed as CD4(+)CD25(high)CD127(-) cells by flow cytometry and cultured for 48 hours in the absence or in the presence of budesonide and/or formoterol at different doses. RESULTS: CD4(+)CD25(high)CD127(-) regulatory T-cells percentage was significantly reduced in COPD patients, both current and former smokers, with respect to volunteers. Furthermore, CD4(+)CD25(high)CD127(-) cells of COPD patients showed a not statistically significant response to drugs compared to healthy subjects. DISCUSSION: Our results evidenced a different behaviour of CD4(+)CD25(high)CD127(-) Treg cells in COPD patients after in vitro treatments. CONCLUSIONS: Based on our data, we suggested a possible role of CD4 CD25(high)CD127 T-cells in COPD pathogenesis.