微卡对哮喘豚鼠肺组织嗜酸粒细胞凋亡及Bcl-2蛋白表达的影响

Effects of M. vaccae on eosinophil apoptosis and Bcl-2 protein expression in lung tissues of asthmatic guinea pigs

目的 :研究微卡对哮喘豚鼠肺组织嗜酸粒细胞凋亡及Bcl- 2蛋白表达的影响。方法 :30只豚鼠随机分为生理盐水组、哮喘组及微卡组 ,每组 10只。微卡组每只豚鼠在OVA致敏前 10d肌注 2 2 5 μg微卡。应用TUNEL法检测肺组织嗜酸粒细胞的凋亡 ,免疫组化法检测肺组织Bcl- 2蛋白的表达。结果 :微卡组豚鼠肺组织嗜酸粒细胞凋亡指数 (2 3 78± 5 4 2 ) %显著高于哮喘组 (4 5 6± 0 6 8) % (P <0 0 1) ;肺组织Bcl- 2蛋白平均积分吸光度值(15 5 6 3± 4 92 4 )显著低于哮喘组 (2 32 1 9± 75 1 2 ) (P <0 0 5 )。结论 :微卡能诱导哮喘豚鼠肺组织嗜酸粒细胞凋亡 ,可能与其抑制Bcl- 2蛋白在哮喘豚鼠肺组织的表达有关。

AIM: To study the effects of M. vaccae on eosinophil apoptosis and Bcl-2 protein expression in lung tissues of asthmatic guinea pigs. METHODS: 30 guinea pigs were divided into normal saline (NS) group, asthma group and M. vaccae treatment group at random, every group included 10 guinea pigs. Guinea pigs in M. vaccae treatment group were injected intramuscularly with 22 5 μg M. vaccae 10 days before OVA immunization. TdT-mediated dUTP nick end labeling (TUNEL) technique was used to investigate the apoptosis of eosinophils and immunohistochemistry method was used to study the expression of Bcl-2 protein in lung tissues. RESULTS: The apoptosis index (AI) of eosinophils in lung tissues in M. vaccae treatment group was significant higher than that in asthma group (23 78±5 42)% vs (4 56±0 68)%, P <0 01]. The mean optical density value of Bcl-2 protein in lung tissues of M. vaccae treatment group was significant lower than that of asthma group ( 1 556 3 ±492 4) vs ( 2 321 9 ±751 2), P< 0 05]. CONCLUSION: The apoptosis of eosinophils induced by M. vaccae in lung tissues of asthmatic guinea pigs may be due to the inhibition of Bcl-2 protein expression.