氨茶碱对哮喘豚鼠嗜酸细胞IL-3、IL-5及GM-CSF受体表达的影响

目的　观察氨茶碱(AM)对嗜酸细胞(Eos)上白介素 5受体α(IL 5Rα)、白介素 3受体α(IL 3Rα)、粒 巨噬细胞集落刺激因子受体α(GM CSFRα)及共同β链(βcR)mRNA表达的影响,探讨茶碱促进哮喘Eos凋亡的机制。方法　 18只健康豚鼠随机分为正常组、哮喘组、茶碱组,每组 6只,以卵蛋白致敏激发制作豚鼠哮喘模型,密度梯度分离法分离支气管灌洗液(BALF)中的低密度Eos(HEos)及正常密度Eos(NEos),以末端脱氧核苷酸转移酶介导的dUTP缺口末端标记(TUNEL)法检测细胞凋亡,原位杂交检测各受体mRNA表达,RT PCR法检测EosIL 5Rα、IL 3Rα相对含量。结果　哮喘组HEos及NEos凋亡 (4±2, 3±2)明显低于正常组(8±2, 7±2,P<0 01),而哮喘组细胞数 (75±13, 51±11 )明显高于正常组(5±2, 10±3,P<0 01)。用AM 24h后不同密度Eos数量 ( 36±14, 33±8 )均明显低于哮喘组 (P<0 01, 0 05),AM组Eos凋亡 ( 15±5, 14±4 )明显高于哮喘组(P<0 01);哮喘组Eos表达IL 5、IL 3及GM CSFα受体mRNA,明显低于正常组 (P<0 01, 0 05 ),AM组中低密度Eos表达各受体mRNA均明显高于哮喘组 (P<0 05 );而哮喘组βcR表达(41±6, 39±7)表达显著高于正常组 (28±5,26±5,P<0 01),AM组βcR表达与哮喘组比较差异无显著性(P>0 05)。HEos表达各受体与NEo

The effects of aminophylline on mRNA expression of interleukin-5,interleukin-3 and granulocyte-macrophage colony-stimulating factor receptors in eosinophils of asthmatic guinea pigs

Aim To investigate the effect of Aminophyllin e(AM) on expression of Interleukin-5 receptor α(IL-5Rα), IL-3Rα, granulocy te- macrophage-colony-stimulating factor receptor α(GM-CSFRα) and common β receptor(βcR) in eosinophils(Eos) of BALF in asthmatic guinea pigs, and mech anism of AM promoting Eos apoptosis. Methods 18 guinea pigs wer e divided into three groups randomly, normal control group, asthma group and AM -treated group. Asthma model of guinea pigs was sensitized by ovalbumin. Hypode nse Eos(HEos) and normodense Eos(NEos) were purified from BALF by gradients of p ercoll. Apoptosis was detected by TUNEL. mRNA expression of IL-5Rα, IL-3Rα, GM-CSFRα and βcR in Eos were measured by RT-PCR and hybridization.Re sults Apoptosis of HEos and NEos in asthma group(4±2,3±2) were low er than that in normal group(8±2,7±2)(P<0.01). Eos apoptosis in AM- treated group(15±5, 14±4) was remarkably higher than that in asthmatic group( P<0.01); Expression of IL-5Rα,IL-3Rα,GM-CSFRα mRNA in Eos from asthma tic group were notably lower, expression of βcR mRNA was higher than that from normal group(P<0.01,0.05). Expression of IL-5Rα,IL-3Rα,GM-CSFRα mR NA in HEos from AM-treated group were significantly higher than that from asthm atic group(P<0.05),while expression of βcR mRNA were not changed. Conclusions Apoptosis of Eos is inhibited in asthma. AM promotes the a poptosis in BALF Eos of guinea pigs with asthma. AM decreases the effect of IL- 5, IL-3, GM-CSF and promoting apoptosis in lung Eos by inducing expression of their α chain mRNA.