Autoimmunity and chronic obstructive pulmonary disease: thinking beyond cigarette smoke

Risk of Chronic Obstructive Pulmonary Disease in Female Adults With Primary Sjögren Syndrome: A Nationwide Population-Based Cohort Study

No large-scale population-based cohort study has ever investigated the risk of developing chronic obstructive pulmonary disease (COPD) in patients with Sjögren syndrome (SS). This study evaluated the risk of COPD in women with primary SS (pSS) in a nationwide population.We used the data of the National Health Insurance Research Database of Taiwan to establish a pSS group consisting of 3013 female adults diagnosed between 2000 and 2005, and a non-SS group consisting of 12,052 women without SS matched by a propensity score. Incident COPD cases were identified to the end of 2011. The pSS group to non-SS group adjusted hazard ratios (aHRs) of COPD were estimated using multivariable Cox proportional hazards regression analysis.After a mean follow-up period of 7.99 years, the incidence of COPD was 1.4-fold greater in the pSS group than in the non-SS group (3.87 vs 2.77 per 1000 person-years) with an aHR of 1.39 (95% confidence interval [CI] = 1.10-1.75, P = 0.007). The COPD incidence was 7-fold greater for women aged 50 years and above than women aged 20 to 49, with the aHR of 4.24 (95% CI = 3.06-5.88, P < 0.001). Comorbidity increased the COPD risk further for women with pSS. Women with both pSS and comorbidity had an aHR of 3.11 (95% CI = 2.23-4.33, P < 0.001) for COPD, compared to those free of both pSS and comorbidity.Women with pSS are at a greater risk of developing COPD than those without SS. Patients with SS require close monitoring to prevent COPD development, particularly for those with comorbidity.

Implications of the inflammatory response for the identification of biomarkers of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by both local and systemic inflammation. Because inflammation plays a critical role in the development, course and severity of COPD, inflammatory markers have the potential to improve the current diagnostic and prognostic approaches. Local inflammation in COPD is characterized by an infiltration of inflammatory cells, with an increased expression of cytokines, chemokines, enzymes, growth factors and adhesion molecules. Systemic low-grade inflammation is another common but nonspecific finding in COPD. Exacerbations of COPD are acute clinical events accompanied by an exaggerated inflammatory response. Future investigations in the field of COPD biomarkers should take into account different study designs and biochemical assays, disease course and duration, variations in symptom severity and timing of measurement.

Immunoregulation of Bone Marrow-Derived Mesenchymal Stem Cells on the Chronic Cigarette Smoking-Induced Lung Inflammation in Rats

Impact of bone mesenchymal stem cell (BMSC) transfusion on chronic smoking-induced lung inflammation is poorly understood. In this study, a rat model of smoking-related lung injury was induced and the rats were treated with vehicle or BMSCs for two weeks. Different subsets of CD4+ T cells, cytokines, and anti-elastin in the lungs as well as the lung injury were characterized. Serum and lung inducible nitric oxide synthase (iNOS) and STAT5 phosphorylation in lymphocytes from lung tissue were also analyzed. Results indicated that transfusion of BMSCs significantly reduced the chronic smoking-induced lung injury, inflammation, and levels of lung anti-elastin in rats. The frequency of Th1 and Th17 cells and the levels of IL-2, IL-6, IFN-γ, TNF-α, IL-17, IP-10, and MCP-1 increased, but the frequency of Tregs and IL-10 decreased. Transfusion of BMSCs significantly modulated the imbalance of immune responses by mitigating chronic smoking-increased Th1 and Th17 responses, but enhancing Treg responses in the lungs of rats. Transfusion of BMSCs limited chronic smoking-related reduction in the levels of serum and lung iNOS and mitigated smoking-induced STAT5 phosphorylation in lymphocytes from lung tissue. BMSCs negatively regulated smoking-induced autoimmune responses in the lungs of rats and may be promising for the intervention of chronic smoking-related lung injury.

Increased incidence of autoimmune markers in patients with combined pulmonary fibrosis and emphysema

Background

Combined pulmonary fibrosis and emphysema (CPFE) is an umbrella term encompassing upper lobe emphysema and lower lobe pulmonary fibrosis with pathogenesis elusive. The aim of our study was to investigate the incidence of autoimmune markers in patients with CPFE.

Methods

In this multicenter study we retrospectively evaluated records from patients with CPFE (n=40) and IPF (n=60) without emphysema. Baseline demographic characteristics, high-resolution computed tomography (HRCT), spirometry, histopathological, treatment, serum immunologic and survival data were investigated. B cell presence was estimated with CD20 immunostaining in representative lung biopsy samples from CPFE patients and control subjects.

Results

A statistically significant increased number of CPFE patients with elevated serum ANA with or without positive p-ANCA titers compared to patients with IPF without emphysema was observed. Patients with CPFE and positive autoimmune markers exhibited improved survival compared to patients with a negative autoimmune profile. A massive infiltration of clusters of CD20+ B cells forming lymphoid follicles within the fibrotic lung in CPFE patients with positive serum immunologic profile compared to patients with negative profile, was noted and positively correlated with improved survival.

Conclusions

A significant proportion of patients with CPFE may present with underlying auto-immune disorders that may reside insidiously and be associated with favorable prognosis. Early identification of these patients using a panel of auto-antibodies may lead to more targeted and effective therapeutic applications.