| 1. |
- Andelid, Kristina, 1953, et al.
(författare)
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Systemic cytokine signaling via IL-17 in smokers with obstructive pulmonary disease: a link to bacterial colonization?
- 2015
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Ingår i: International Journal of Chronic Obstructive Pulmonary Disease. - : Informa UK Limited. - 1178-2005. ; 10, s. 689-702
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Tidskriftsartikel (refereegranskat)abstract
- We examined whether systemic cytokine signaling via interleukin (IL)-17 and growth-related oncogene-alpha (GRO-alpha) is impaired in smokers with obstructive pulmonary disease including chronic bronchitis (OPD-CB). We also examined how this systemic cytokine signaling relates to bacterial colonization in the airways of the smokers with OPD-CB. Currently smoking OPD-CB patients (n=60, corresponding to Global initiative for chronic Obstructive Lung Disease [ GOLD] stage I-IV) underwent recurrent blood and sputum sampling over 60 weeks, during stable conditions and at exacerbations. We characterized cytokine protein concentrations in blood and bacterial growth in sputum. Asymptomatic smokers (n=10) and never-smokers (n=10) were included as control groups. During stable clinical conditions, the protein concentrations of IL-17 and GRO-alpha were markedly lower among OPD-CB patients compared with never-smoker controls, whereas the asymptomatic smoker controls displayed intermediate concentrations. Notably, among OPD-CB patients, colonization by opportunistic pathogens was associated with markedly lower IL-17 and GRO-alpha, compared with colonization by common respiratory pathogens or oropharyngeal flora. During exacerbations in the OPD-CB patients, GRO-alpha and neutrophil concentrations were increased, whereas protein concentrations and messenger RNA for IL-17 were not detectable in a reproducible manner. In smokers with OPD-CB, systemic cytokine signaling via IL-17 and GRO-alpha is impaired and this alteration may be linked to colonization by opportunistic pathogens in the airways. Given the potential pathogenic and therapeutic implications, these findings deserve to be validated in new and larger patient cohorts.
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| 2. |
- Levanen, B., et al.
(författare)
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Impact of tobacco smoking on cytokine signaling via interleukin-17A in the peripheral airways
- 2016
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Ingår i: International Journal of Chronic Obstructive Pulmonary Disease. - : Informa UK Limited. - 1178-2005. ; 11, s. 2109-2116
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Tidskriftsartikel (refereegranskat)abstract
- There is excessive accumulation of neutrophils in the airways in chronic obstructive pulmonary disease (COPD) but the underlying mechanisms remain poorly understood. It is known that extracellular cytokine signaling via interleukin (IL)-17A contributes to neutrophil accumulation in the airways but nothing is known about the impact of tobacco smoking on extracellular signaling via IL-17A. Here, we characterized the impact of tobacco smoking on extracellular cytokine signaling via IL-17A in the peripheral airways in long-term smokers with and without COPD and in occasional smokers before and after short-term exposure to tobacco smoke. We quantified concentrations of IL-17A protein in cell-free bronchoalveolar lavage (BAL) fluid samples (Immuno-quantitative PCR) and cytotoxic T-cells (immunoreactivity for CD8(+) and CD3(+)) in bronchial biopsies. Matrix metalloproteinase-8 and human beta defensin 2 proteins were also quantified (enzyme-linked immunosorbent assay) in the BAL samples. The concentrations of IL-17A in BAL fluid were higher in long-term smokers without COPD compared with nonsmoking healthy controls, whereas those with COPD did not differ significantly from either of the other groups. Short-term exposure to tobacco smoke did not induce sustained alterations in these concentrations in occasional smokers. Long-term smokers displayed higher concentrations of IL-17A than did occasional smokers. Moreover, these concentrations correlated with CD8(+) and CD3(+) cells in biopsies among long-term smokers with COPD. In healthy nonsmokers, BAL concentrations of matrix metalloproteinase-8 and IL-17A correlated, whereas this was not the case in the pooled group of long-term smokers with and without COPD. In contrast, BAL concentrations of human beta defensin 2 and IL-17A correlated in all study groups. This study implies that long-term but not short-term exposure to tobacco smoke increases extracellular cytokine signaling via IL-17A in the peripheral airways. In the smokers with COPD, this signaling may involve cytotoxic T-cells. Long-term exposure to tobacco smoke leads to a disturbed association of extracellular IL-17A signaling and matrix metalloproteinase-8, of potential importance for the coordination of antibacterial activity.
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