engleski

Chronic activation of polymorphonuclear leukocytes in COPD patients

Background: Cigarette smoking is a major risk factor for chronic obstructive pulmonary disease (COPD). Exposure to cigarette smoke and subsequent inflammatory response may cause a secretion of cellular proteases involved in a degradation of extracellular matrix in lungs. Objective: The aim of this study was to evaluate the difference in release of matrix metalloproteinase-9 (MMP-9) from polymorphonuclear leukocytes (PMN) between patients with COPD and healthy controls. Materials and Methods: The study included 23 patients with stable COPD and 9 healthy controls. PMN were isolated from blood of all participants and exposed to 4 % cigarette smoke extract (CSE) or basal culture media (as a control). After 20 h incubation, MMP-9 concentration and LDH activity were measured in PMN culture media using the ELISA and spectrophotometric method, respectively. Statistical analysis was performed using the SigmaStat program. Results: Exposure of PMN to 4 % CSE during 20 h incubation did not cause changes in LDH activity in PMN culture media comparing to untreated PMN (P=0.689), showing no toxic effects of CSE towards PMN under these conditions. In basal conditions when no stimulation was applied, PMN of COPD patients released significantly more MMP-9 compared with PMN of healthy controls (P=0.016). Stimulation of PMN of healthy controls with CSE increased the release of MMP-9 into the culture media (P=0.025), while no further increase over the high basal secretion rate was found in COPD patients. Conclusions: Results are showing chronic activation of PMN in patients with COPD and suggesting their indirect role in the degradation of extracellular matrix in lungs.

chronic obstructive pulmonary disease ; cigarette smoke extract ; matrix metalloproteinase-9 ; poymorphonuclear leukocytes

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