胸腺基质淋巴细胞生成素在1-氯-2,4-二硝基苯致敏诱导皮炎小鼠中的表达

The expression of thymic stromal lymphopoietin in a mouse model of dermatitis induced by 1-chloro-2,4-dinitrobenzene

目的:了解胸腺基质淋巴细胞生成素(TSLP)在1-氯-2,4-二硝基苯(DNCB)致敏诱导皮炎小鼠中的表达,并评价TSLP在小鼠皮炎免疫反应中的作用。方法:将20只11周龄SPF级BALB/c小鼠随机分为2组(每组10只):致敏组先后接受含1.0%和0.1%DNCB的橄榄油丙酮(4∶1)溶液反复刺激背部皮肤,对照组接受基质溶液(橄榄油∶丙酮=4∶1)涂抹背部皮肤。实验期间观察小鼠皮炎症状,监测小鼠挠痒次数和皮炎症状评分,观察皮肤组织病理改变。21 d后检测2组血浆总Ig E水平;利用实时荧光定量聚合酶链式反应(q PCR)法检测皮肤、肝脏、脾脏和肾脏组织中TSLP m RNA水平,采用western-blot法分析TSLP蛋白表达情况。结果:2组小鼠的抓挠次数和皮炎症状评分分别在致敏第8天和第6天后出现差异(P<0.05);致敏组小鼠血浆总Ig E水平[(132.61±14.89)μg/L]较对照组[(109.13±2.51)μg/L]显著升高(t=4.92,P<0.05)。与对照组(1)相比,致敏组皮肤(1.83)、脾脏(1.06)和肾脏(1.10)组织中TSLP m RNA相对表达量均升高,而肝脏(0.90)组织TSLP m RNA相对表达量降低,但组间比较差异均无统计学意义(P均>0.05)。Western-blot结果示TSLP蛋白在上述组织中的表达均无差异。结论:TSLP在DNCB致敏诱导皮炎小鼠的皮肤、肝脏、脾脏和肾脏组织中表达均无明显差异,其在小鼠皮炎免疫反应中的作用仍需进一步的研究。

Objective： To determine the expression levels of thymic stromal lymphocytes（TSLP） and its role in immune re- sponse in dermatitis induced by 1-chloro-2,4-dinitrobenzene（DNCB）. Methods： Twenty l 1-week-old SPF BALB/c mice were randomly divided into 2 groups（10 miee per group）. Dermatitis was induced by topical application of 1.0% DNCB in vehicle （olive oil/acetone, 4/1）, following by 0.1% DNCB on the back skin. The control group was given vehicle alone. In addition to dermatitis scores and scratching counts, changes in cutaneous pathology were also evaluated. Total IgE levels were mea- sured 21 days after sensitization. TSLP mRNA and protein levels in the skin, liver, spleen and kidney were evaluated with qPCR and western blot, respectively. Results： Both scratching counts and dermatitis scores were significantly different between the two groups 6 and 8 days after sensitization（P〈0.05）. Total IgE levels were significantly higher in dermatitis than in con- trols[（132.61±14.89）μg/Lvs. （109.13±2.51）μg/L, t=4.92, P〈0.05]. In comparison with controls, expression levels of TSLP mR- NA increased in all tissues except the liver（P all〉0.05 between groups）. Expression levels of TSLP protein did not differ sig- nificantly among these tissues. Conclusions： Expression levels of TSLP in the skin, liver, spleen and kidney are no dramatic differences between DNCB induced dermatitis and normal mice. Further studies are required to elucidate the role of TSLP in immune response in dermatitis induced by DNCB.