Changes in Sputum T-lymphocyte Subpopulations at the Onset of Severe Exacerbations of Chronic Obstructive Pulmonary Disease

Respir Med. 2005 May;99(5):572-9. doi: 10.1016/j.rmed.2004.10.005. Epub 2004 Nov 13.

Abstract

CD8+ve T-cell responses play a primary role in chronic obstructive pulmonary disease (COPD), but there is little information regarding COPD exacerbations. Sputum induction is a relatively non-invasive and safe method to study airway inflammation. The aim of the study was to investigate changes in airway T-lymphocyte subpopulations at the onset of severe COPD exacerbations via analysis of sputum. Induced sputum samples were collected from 12 COPD patients aged (mean+/-sd) 69+/-7 years, ex-smokers (68+/-23 pack-years), mean FEV1 (%predicted) 40+/-14 at the onset of an acute severe exacerbation requiring hospital admission and 16 weeks after remission of the exacerbation. Inflammatory cells and T-lymphocyte subpopulations (CD4, CD8, Tc1, Tc2) were measured using chemical and double immunocytochemical methods. Increased percentages of sputum neutrophils (P=0.002) and decreased CD4/CD8 and CD8-IFNgamma/CD8-IL4+ve (Tc1/Tc2) cell ratios (P=0.03, P=0.02, respectively) were found at the onset of exacerbation compared to stable state. We conclude that a CD8+ve type-2-mediated immune response is induced at the onset of severe COPD exacerbation.

MeSH terms

  • Acute Disease
  • Aged
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology*
  • Female
  • Humans
  • Immunohistochemistry
  • Lymphocyte Count
  • Male
  • Middle Aged
  • Pulmonary Disease, Chronic Obstructive / immunology*
  • Smoking / immunology
  • Sputum / cytology
  • Sputum / immunology*
  • Statistics, Nonparametric
  • Th1 Cells / immunology
  • Th2 Cells / immunology