Chest
Laboratory and Animal InvestigationsExpression of Adhesion Molecules During Apoptosis of Circulating Neutrophils in COPD
Section snippets
Population and Ethics
Patients with COPD (14 patients) were recruited from the outpatient clinic of our institution. All patients were considered to be clinically stable because none of them had required medical attention and/or a change in their regular therapy (ie, inhaled bronchodilators) during the previous 4 months. None of them had been treated with inhaled or oral corticosteroids. Patients with bronchial asthma, pneumonia, or lung cancer were specifically excluded. Smokers with normal lung function (eight
Clinical Data
Table 1 shows the main clinical and lung function variables of all participants. All of them were men of similar age. The smoking history of patients with COPD was similar to that of smokers with normal lung function. None of the former was a current smoker (Table 1). COPD patients showed moderate-to-severe airflow obstruction and mild-to-moderate hypoxemia (Table 1). By design, the results of forced spirometry were normal in smokers with normal lung function and in healthy nonsmokers (Table 1).
Discussion
This study investigated potential alterations in the process of neutrophil apoptosis in COPD patients that may eventually contribute to the characteristic neutrophil accumulation described in the lungs of these patients.220 The main finding of our study was that, compared to smokers with normal lung function and never-smokers, circulating neutrophils harvested from patients with COPD show similar dynamics of apoptosis in culture, but a differential expression of two adhesion molecules (Mac-1
Conclusions
We found that, quantitatively, the rate of neutrophil apoptosis in vitro is not abnormal in COPD patients compared to healthy smokers or never-smokers. However, our study has identified qualitative differences in the surface expression of several adhesion molecules during the apoptotic process that can contribute to the perpetuation of the inflammatory state that characterizes COPD. The precise relevance of these observations in vivo requires further studies aimed at investigating neutrophil
ACKNOWLEDGMENT
The authors thank C. Erasmo and M. Bosch, for their technical collaboration during the study, and Dr. A. De la Peña (Unidad de Investigación) for his help with the statistical analysis.
References (28)
- et al.
Neutrophils from subjects with chronic obstructive lung disease show enhanced chemotaxis and extracellular proteolysis
Lancet
(1987) - et al.
Glomerular mesangial cells and inflammatory macrophages ingest neutrophils undergoing apoptosis
Kidney Int
(1992) - et al.
Human neutrophils lose their surface FcgRIII and acquire annexin V binding sites during apoptosisin vitro
Blood
(1995) - et al.
Leukocyte-endothelial adhesion molecules
Blood
(1994) - et al.
Previous uptake of apoptotic neutrophils or ligation of integrin receptors down-modulates the ability of macrophages to ingest apoptotic neutrophils
Blood
(1999) - et al.
Global strategy for the diagnosis, management and prevention of chronic obstructive pulmonary disease: NHLBI/WHO Global Initiative for Chronic Obstructive Lung Disease (GOLD) workshop summary
Am J Respir Crit Care Med
(2001) Structural and inflammatory changes in COPD: a comparison with asthma
Thorax
(1998)- et al.
Macrophage engulfment of apoptotic neutrophils contributes to the resolution of acute pulmonary inflammationin vivo.
Am J Respir Cell Mol Biol
(1995) - et al.
Expression of adhesion molecules and G proteins in circulating neutrophils in chronic obstructive pulmonary disease
Am J Respir Crit Care Med
(1998) - et al.
Enhanced neutrophil response in chronic obstructive pulmonary disease
Thorax
(2001)
Influence ofin vivoprednisolone on increasedin vitroO2−generation by neutrophils in emphysema
Eur J Respir Dis
Resolution of acute inflammation and the role of apoptosis in the tissue fate of granulocytes
Clin Sci
Bronchial epithelial cell-derived cytokines (G-CSF and GM-CSF) promote the survival of peripheral blood neutrophils
Am J Respir Cell Mol Biol
Multiple epithelial cell-derived factors enhance neutrophil survival: regulation by glucocorticoids and tumor necrosis factor-alpha
Am J Respir Crit Care Med
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Supported, in part, by Sociedad Española de Neumología y Cirucía Torácica, Associació Balear per L'estudi de las Malaltios Respiratorios. Red Respira (RTIC 0311, Fondo de Investigacioues Sanitarias, Instituto de Sahid Carlos III), and Fondo de Investigaciones Sanitarias grant No. 01/0830.