Cytokine production by bronchoalveolar lavage T lymphocytes in chronic obstructive pulmonary disease.
BACKGROUND
T lymphocytes (predominantly CD8+ cells) have previously been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD).


OBJECTIVE
We sought to describe the profile of cytokine production by CD8+ and CD4+ cells isolated from bronchoalveolar lavage fluid.


METHODS
Bronchoalveolar lavage was performed in 11 patients with COPD (median FEV1, 63.3% of predicted value) and 9 healthy control subjects. CD8+ and CD4+ T cells were isolated by means of positive selection after macrophage depletion. CD8+ and CD4+ cells were activated with anti-CD3/CD28 antibodies for 60 hours before restimulation with phorbol 12-myristate 13-acetate-ionomycin and brefeldin. Three-color flow cytometry was used to simultaneously measure levels of intracellular cytokines.


RESULTS
IL-4 was expressed by a higher percentage of stimulated CD8+ T cells (TC2) compared with CD4+ T cells (TH2) in patients with COPD (P = .01). In contrast, IFN-gamma was expressed in a significantly higher percentage of stimulated CD4+ T cells (TH1) than CD8+ T cells (TC1) in the COPD group (P = .04). TNF-alpha was expressed by almost all TC1 and TH1 cells, with virtually no expression by TC2 and TH2 cells. In addition, a small number of T cells expressing TNF-alpha alone without concomitant IFN-gamma or IL-4 expression were seen in the majority of subjects. There was a higher percentage of TC2 cells in subjects with COPD compared with that seen in the control group (P = .03). Stimulation with anti-CD3/CD28 antibodies increased the percentage of TC2 cells and decreased the percentage of TH2 cells.


CONCLUSIONS
Our results suggest that there are increased numbers of TC2-like cytokine-expressing cells in the lungs of patients with COPD.


CONCLUSIONS
These cells might be a source of TH2 cytokines, which might, at least in part, explain the lung eosinophilia associated with COPD exacerbations.
Barczyk
Adam
A
Airways Disease Section, National Heart and Lung Institute, Imperial College, London, UK.
Pierzchała
Władysław
W
Kon
Onn M
OM
Cosio
Borja
B
Adcock
Ian M
IM
Barnes
Peter J
PJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology* / Q000276:immunology; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D002469:Cell Separation; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis* / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000276:immunology / Q000378:metabolism*
D016207:Cytokines