母牛分枝菌菌苗对哮喘豚鼠肺组织嗜酸粒细胞凋亡及Fas、bcl-2蛋白表达的影响

Effects of mycobacterium vaccae vaccine on eosinophil apoptosis,protein expression of Fas and bcl-2 in lung tissues of asthmatic guinea pig

目的:研究母牛分枝杆菌菌苗对哮喘豚鼠肺组织嗜酸粒细胞凋亡及Fas、bcl-2蛋白表达的影响。方法:30只豚鼠随机分为生理盐水组、哮喘组及母分枝杆菌菌苗组。应用卵白蛋白(OVA)建立哮喘模型,母牛分枝杆菌菌苗组每只豚鼠在OVA致敏前10天肌注22.5μg母牛分枝杆菌菌苗。最后一次激发后,TUNEL法检测肺组织嗜酸粒细胞凋亡,免疫组化法检测肺组织Fas、bcl-2蛋白的表达。结果:母牛分枝杆菌菌苗组豚鼠肺组织嗜酸粒细胞凋亡指数(23.8±5.4)%显著高于哮喘组(4.6±0.7)%(P<0.01);肺组织Fas蛋白表达(OD值)(0.202±0.013)显著高于哮喘组(0.051±0.025)(P<0.01);肺组织bcl-2蛋白表达(OD值)(0.054±0.032)显著低于哮喘组(0.181±0.041)(P<0.01)。结论:母牛分枝杆菌菌苗通过上调Fas蛋白、下调bcl-2蛋白在哮喘豚鼠肺组织的表达而诱导哮喘豚鼠肺组织嗜酸粒细胞凋亡。

Objective:To study the effects of Mycobacterium vaccae vaccine on eosinophil apoptosis,protein expression of Fas and bcl-2 in lung tissues of asthmatic guinea pig.Methods:30 guinea pigs were randomly divided into NS,asthma and Mycobacterium vaccae vaccine group.A guinea pig model of asthma was estbalished with OVA(ovalbumin).Each guinea pig of Mycobacterium vaccae vaccine group was injected intramuscularly with 22.5μg of Mycobacterium vaccae vaccine 10 days before OVA immunization.After the last challenge,TdT-mediated dUTP nick end labeling (TUNEL)technique was used to determine the apoptosis of eosinophils and immunohistochemistry method was used to determine protein expression of Fas and bcl-2 in lung tissue sections.Results:Guinea pigs of Mycobacterium vaccae vaccine group had a higher AI(apoptosis index) of eosinophils in lung tissues[(23.8±5.4)%]than that of asthma group[(4.6±0.7)%,P<0.01],a higher expression of Fas protein(optical density value,OD value)in lung tissues[(0.202±0.013)]than that of asthma group[(0.051±0.025),P<0.01],and a lower expression of bcl-2 protein(OD value)in lung tissues[0.054±0.032)]than that of asthma group[0.181±0.041),P<0.01].Conclusion:Mycobacterium vaccae vaccine can induce the apoptosis of eosinophils in lung tissues of asthmatic guinea pigs by up-regulating the expression of Fas protein and down-regulating the expression of bcl-2 protein in lung tissues.