Airway neutrophils apoptosis in children with severe asthma / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the changes of neutrophils in airway inflammation in children with severe asthma.</p><p><b>METHOD</b>Children with mild to moderate asthma (n=23), severe asthma (n=16) and healthy control subjects (n=16) underwent lung function tests and sputum induction. The sputum specimens were assayed for cellular differential count, the supernatant and peripheral blood were assayed for the concentrations of IL-8 by "sandwich" enzyme linked immunosorbent assay (ELISA). Sputum supernatant, IL-8 and mifepristone were assessed for their abilities to prolong the in vitro survival of blood-derived neutrophils.</p><p><b>RESULT</b>The percentage of sputum neutrophils was significantly higher in severe asthmatics [59.54 (41.99-74.65)%] than mild-moderate asthmatics [30.03 (15.94-47.71)%] and healthy control subjects [29.72(16.53-45.74)%] (P < 0. 01); the level of IL-8 in sputum was significantly higher in severe asthmatics [2907.78 (331.67 - 3457.93) ng/L] than mild-moderate asthmatics [287.58 (130.75-656.84) ng/L] and healthy control subjects [179.2 (58.55-346.59) ng/L] (P < 0.01); the percentages of neutrophilic apoptosis respectively cultured with LPS [(10.57 +/- 1.97)%], severe asthmatics supernatant [(11.82 +/- 2.96)%], IL-8 [(10.47 +/- 1.93)%], dexamethasone [(9.93 +/- 1.95)%], severe asthma supernatant + mifepristone [(12.15 +/- 2.86)%] in vitro were lower than that cultured with PBS [(17.98 +/- 2.27)%], healthy control supernatant [(17.37 +/- 2.50)%], mild-moderate asthmatics supernatant [(16.35 +/- 3.26)%], mifepristone [(17.89 +/- 2.38)%], and dexamethasone + mifepristone [(17.06 +/- 2.59)%] (P < 0.01).</p><p><b>CONCLUSION</b>Suppression of neutrophilic apoptosis seems to play a potential role in airway neutrophilic inflammation in severe asthmatics, and the level of IL-8 in sputum was significantly higher in patients with severe asthmatics.</p>

Eosinophils apoptosis in asthmatic children / 中华儿科杂志

<p><b>UNLABELLED</b>Prominent eosinophil airway inflammation is important in the pathogenesis of asthma. There is increasing evidence that the disorder of eosinophil apoptosis contributes to the mechanism. But most of the studies have been done in vitro or on animal models, very few were done among the adult asthmatics in vivo.</p><p><b>OBJECTIVE</b>The aim of this study was to elucidate the relationship between the apoptotic eosinophils and Bcl-2 in asthmatic children in vivo.</p><p><b>METHODS</b>Eleven mild to moderate asthmatic patients were recruited and the range of age was 7 - 14 years (9 males, 2 females), meanwhile 7 patients with lower respiratory infection were recruited as control and the range of age was 9 - 14 years (5 males, 2 females). Before and after inhaled glucocorticoid (GC) induced sputum, bronchoalveolar lavage (BAL), bronchial mucosa specimens and peripheral blood were obtained for measuring and comparing the changes of apoptotic EG(2)(+) cell by combining the techniques of TUNEL and immunohistochemistry, meanwhile the expression of Bcl-2 in bronchial mucosa specimens was measured by using the immunohistochemical assay.</p><p><b>RESULTS</b>Before the inhalation of GC, the apoptotic EG(2)(+) cells in asthmatics were significantly lower than that in control group (P < 0.01), and the numbers of EG(2)(+) cell in asthmatics group were significantly higher than that in control group (P < 0.001). After the treatment apoptotic EG(2)(+) cells in asthmatics were increased (P < 0.01), and the numbers of EG(2)(+)cell were decreased (P < 0.01, P < 0.05 and P < 0.05, respectively), FEV(1)% was increased (P < 0.05). Before the inhalation of GC, the numbers of Bcl-2(+) cell in asthmatic airway submucosa were higher than that in control group (P < 0.05) but after the treatment the number of Bcl-2(+) cell did not change significantly. (4) Before and after GC treatment the percentages of apoptotic eosinophils of peripheral blood in vivo had no significant changes compared with those of control subjects (P > 0.05). There was a positive correlation between apoptosis of EG(2)(+) cell in sputum, BAL, airway submucosa and FEV(1)% (P < 0.05).</p><p><b>CONCLUSION</b>Apoptosis of EG(2)(+) cell decreased in the airway of asthmatic children and inducing EOS apoptosis is one of the important mechanism of inhaled GC therapy for asthma.</p>