부산대학교 도서관

Background: Apoptosis of eosinophils is of increasingly important value in modulating allergic airway inflammation in asthma. Our purpose was to investigate the degree of expression of the antiapoptotic B-cell lymphoma/leukaemia-2 (Bcl-2) protein in sputum eosinophils daring acute asthma exacerbation and its relationship with exacerbation severity. Methods: Sputum was obtained from 33 asthmatic children and 15 healthy children as a control group. Patients were studied daring an acute asthma exacerbation. They were classified according to the severity of exacerbation into mild, moderate and severe (n = 11 for each). Patients with severe exacerbation were followed up until remission and another sputum sample was obtained. Number of sputum eosinophils was expressed as percentage of leucocytes. Bcl-2 expression in sputum eosinophils was assessed by immunohistochernical staining techniques; the results were expressed as percentage of positively stained cells over total eosinophils. Results: Sputum eosinophils and Bcl-2+ eosinophils' percentages were significantly higher in patients with acute exacerbation than controls (P<0.01). Patients with severe exacerbation had significantly higher sputum Bcl-2+ eosinophils' percentage than those with mild-to-moderate exacerbation (mean + SD = 42.4 ± 3 1.96% vs. 5.7 ± 14.5%, P< 0.01). A significant negative correlation was found between Bci-2+ eosinophils' percentage and peak expiratory flow rate % predicted (P< 0.05); After remission, patients with severe exacerbation showed a significant decrease of Bcl-2 eosinophils' percentage (P< 0.05). Conclusion Our findings suggest that Bcl-2 prolongs survival and decreases apoptosis of airway eosinophils in asthma especially during exacerbation. Eosinophil apoptosis and Bcl-2 represent a target for new and effective therapeutic strategies of asthma. [ABSTRACT FROM AUTHOR]