Computed tomographic scan-diagnosed chronic obstructive pulmonary disease-emphysema: eotaxin-1 is associated with bronchodilator response and extent of emphysema.
BACKGROUND
Bronchodilator responses are a hallmark of asthma and a subset of chronic obstructive pulmonary disease (COPD). We evaluated subjects with COPD and computed tomographic (CT) scan evidence of emphysema to determine the biomarker profile associated with a bronchodilator response.


OBJECTIVE
We investigated whether subjects with COPD and a bronchodilator response had increased levels of bronchoalveolar lavage (BAL) fluid eosinophil biomarkers, T(H)2 cytokines, CC chemokines, and serum allergen-specific IgE.


METHODS
All patients with COPD and control subjects (n = 31) had chest CT scans to detect emphysema and subsequent pulmonary function studies, BAL for biomarkers, and serum IgE measurements.


RESULTS
CT scan score, FEV(1), carbon monoxide single-breath diffusion capacity, and BAL fluid neutrophil biomarker levels were similar in subjects with COPD who had or did not have a bronchodilator response of greater than 12%. In contrast, levels of BAL fluid eosinophil biomarkers (eosinophil cationic protein [ECP] and eotaxin-1) were greater in patients with COPD with a bronchodilator response, whereas T(H)2 cytokines were not detectable in any patients with COPD. BAL fluid ECP and eotaxin-1 levels correlated with CT scan extent of emphysema. Immunostaining of COPD lung sections from a separate cohort of subjects with COPD and healthy subjects demonstrated epithelial expression of eotaxin-1 but no lung expression of IL-4 or IL-5.


CONCLUSIONS
Subjects with COPD diagnosed on the basis of the presence of emphysema on CT scan who have a bronchodilator response have increased levels of BAL ECP and eotaxin-1 but not T(H)2 cytokines.


CONCLUSIONS
Eosinophil biomarkers (ECP-1 and eotaxin-1) might identify a subset of subjects with COPD with emphysema on CT scans who have a bronchodilator response and an increased extent of emphysema on CT scanning.
Miller
Marina
M
Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0635, USA.
Ramsdell
Joe
J
Friedman
Paul J
PJ
Cho
Jae Youn
JY
Renvall
Marian
M
Broide
David H
DH
D000368:Aged; D015415:Biomarkers / Q000032:analysis; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D054413:Chemokine CCL11 / Q000032:analysis*; D018946:Chemokine CCL5 / Q000032:analysis; D047150:Eosinophil Cationic Protein / Q000032:analysis; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000473:pathology; D014057:Tomography, X-Ray Computed
D015415:Biomarkers; D001993:Bronchodilator Agents; D054413:Chemokine CCL11; D018946:Chemokine CCL5; D007073:Immunoglobulin E; D047150:Eosinophil Cationic Protein