Increased levels of the chemokines GROalpha and MCP-1 in sputum samples from patients with COPD.
BACKGROUND
Patients with chronic obstructive pulmonary disease (COPD) have increased numbers of neutrophils and macrophages in their lungs. Growth related oncogene-alpha (GROalpha) attracts neutrophils, whereas monocyte chemoattractant protein-1 (MCP-1) attracts monocytes that can differentiate into macrophages. The aim of this study was to determine the concentration of GROalpha and MCP-1 in bronchoalveolar lavage (BAL) fluid and sputum from non-smokers, healthy smokers and patients with COPD, and to see if there was a correlation between the concentrations of these chemokines, lung function, and numbers of inflammatory cells.


METHODS
BAL fluid and sputum from non-smokers (n=32), healthy smokers (n=36), and patients with COPD (n=40) were analysed for the presence of GROalpha and MCP-1 using ELISA. Cells counts were performed on the samples and correlations between the concentrations of these chemokines, lung function, and inflammatory cells observed.


RESULTS
Median (SE) GROalpha and MCP-1 levels were significantly increased in sputum from patients with COPD compared with non-smokers and healthy smokers (GROalpha: 31 (11) v 2 (2) v 3 (0.8) ng/ml; MCP-1: 0.8 (0.4) v 0.2 (0.1) v 0.1 (0.04) ng/ml, p<0.05), but not in BAL fluid. There were significant negative correlations between both GROalpha and MCP-1 levels in sputum and forced expiratory volume in 1 second (FEV(1)) % predicted (GROalpha: r=-0.5, p<0.001; MCP-1: r=-0.5, p<0.001), together with significant positive correlations between GROalpha and MCP-1 and neutrophil numbers in sputum (GROalpha: r=0.6, p<0.001; MCP-1: r=0.4, p<0.01).


CONCLUSIONS
These results suggest that GROalpha and MCP-1 are involved in the migration of inflammatory cells, thus contributing to the inflammatory load associated with COPD.
Traves
S L
SL
Department of Thoracic Medicine, National Heart and Lung Institute, Imperial College, School of Medicine, Dovehouse Street, London SW3 6LY, UK.
Culpitt
S V
SV
Russell
R E K
RE
Barnes
P J
PJ
Donnelly
L E
LE
D000328:Adult; D015415:Biomarkers; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002452:Cell Count; D018932:Chemokine CCL2 / Q000378:metabolism*; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors / Q000378:metabolism*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006133:Growth Substances / Q000378:metabolism*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008264:Macrophages / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000737:chemistry; D029424:Pulmonary Disease, Chronic Obstructive / Q000209:etiology* / Q000378:metabolism; D012907:Smoking / Q000378:metabolism; D013183:Sputum / Q000166:cytology / Q000378:metabolism*
D015415:Biomarkers; C475829:CXCL1 protein, human; D018932:Chemokine CCL2; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins