Long-term smoking alters abundance of over half of the proteome in bronchoalveolar lavage cell in smokers with normal spirometry, with effects on molecular pathways associated with COPD.

BACKGROUND: Smoking represents a significant risk factor for many chronic inflammatory diseases, including chronic obstructive pulmonary disease (COPD). METHODS: To identify dysregulation of specific proteins and pathways in bronchoalveolar lavage (BAL) cells associated with smoking, isobaric tags for relative and absolute quantitation (iTRAQ)-based shotgun proteomics analyses were performed on BAL cells from healthy never-smokers and smokers with normal lung function from the Karolinska COSMIC cohort. Multivariate statistical modeling, multivariate correlations with clinical data, and pathway enrichment analysis were performed. RESULTS: Smoking exerted a significant impact on the BAL cell proteome, with more than 500 proteins representing 15 molecular pathways altered due to smoking. The majority of these alterations occurred in a gender-independent manner. The phagosomal- and leukocyte trans endothelial migration (LTM) pathways significantly correlated with FEV1/FVC as well as the percentage of CD8+ T-cells and CD8+CD69+ T-cells in smokers. The correlations to clinical parameters in healthy never-smokers were minor. CONCLUSION: The significant correlations of proteins in the phagosome- and LTM pathways with activated cytotoxic T-cells (CD69+) and the level of airway obstruction (FEV1/FVC) in smokers, both hallmarks of COPD, suggests that these two pathways may play a role in the molecular events preceding the development of COPD in susceptible smokers. Both pathways were found to be further dysregulated in COPD patients from the same cohort, thereby providing further support to this hypothesis. Given that not all smokers develop COPD in spite of decades of smoking, it is also plausible that some of the molecular pathways associated with response to smoking exert protective mechanisms to smoking-related pathologies in resilient individuals. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02627872 ; Retrospectively registered on December 9, 2015.

Proteomic profiling of lung immune cells reveals dysregulation of phagocytotic pathways in female-dominated molecular COPD phenotype.

BACKGROUND: Smoking is the main risk factor for chronic obstructive pulmonary disease (COPD). Women with COPD who smoke experienced a higher risk of hospitalization and worse decline of lung function. Yet the mechanisms of these gender-related differences in clinical presentations in COPD remain unknown. The aim of our study is to identify proteins and molecular pathways associated with COPD pathogenesis, with emphasis on elucidating molecular gender difference. METHOD: We employed shotgun isobaric tags for relative and absolute quantitation (iTRAQ) proteome analyses of bronchoalveolar lavage (BAL) cells from smokers with normal lung function (n = 25) and early stage COPD patients (n = 18). Multivariate modeling, pathway enrichment analysis, and correlation with clinical characteristics were performed to identify specific proteins and pathways of interest. RESULTS: More pronounced alterations both at the protein- and pathway- levels were observed in female COPD patients, involving dysregulation of the FcγR-mediated phagocytosis-lysosomal axis and increase in oxidative stress. Alterations in pathways of the phagocytosis-lysosomal axis associated with a female-dominated COPD phenotype correlated well with specific clinical features: FcγR-mediated phagocytosis correlated with FEV1/FVC, the lysosomal pathway correlated with CT < -950 Hounsfield Units (HU), and regulation of actin cytoskeleton correlated with FEV1 and FEV1/FVC in female COPD patients. Alterations observed in the corresponding male cohort were minor. CONCLUSION: The identified molecular pathways suggest dysregulation of several phagocytosis-related pathways in BAL cells in female COPD patients, with correlation to both the level of obstruction (FEV1/FVC) and disease severity (FEV1) as well as emphysema (CT < -950 HU) in women. TRIAL REGISTRATION: No.: NCT02627872 , retrospectively registered on December 9, 2015.

Hypoxia but not cigarette smoke modulates VEGF secretion from human T cells.

Vascular endothelial growth factor (VEGF) is an important mitogen with multiple functions. In the present study we investigated whether T cell secreted VEGF and inflammatory cytokines were modulated by cigarette smoke and by a hypoxic microenvironment. T cells from peripheral blood of healthy donors were activated under normoxia (21% O(2)) or hypoxia (1-2% O(2)) with or without exposure to cigarette smoke extract. T cells were also obtained from patients with chronic obstructive pulmonary disease (COPD), a smoking-related disease characterized by accumulation of both CD4+ and CD8+T cells. Hypoxia stimulated VEGF secretion from activated T cells, whereas the release of IL-4, IL-6, IL-10, IL-13, IFN-gamma and tumour necrosis factor were not altered. Cigarette smoke extract did not affect VEGF secretion neither in hypoxia nor in normoxia, whereas the secretion of all cytokines was inhibited by the extract in both conditions. When recombinant VEGF was added the smoke-induced inhibition of the IFN-gamma and IL-13 was not observed. Activated T cells from COPD-patients secreted significantly (p < 0.05) more VEGF compared to T cells from healthy individuals. Our data suggest that both cigarette smoke extract and hypoxia modulate the T cell response. This may be of importance in diseases characterized by T cell accumulation, such as COPD.