舌下含服粉尘螨疫苗免疫治疗法对哮喘小鼠树突状细胞及NF-κB的影响

Effect of Dust Mite Vaccine Sublingual Immunotherapy on Dendritic Cells and NF-κB in Asthma Mice

目的通过对哮喘模型小鼠舌下含服粉尘螨疫苗进行治疗,研究治疗前后树突状细胞(dendritic cell,DC)和NF-κB在颌下淋巴结和肺部的变化,比较高剂量疫苗和低剂量疫苗对哮喘小鼠的治疗疗效。方法采用常规方法制备舌下含服粉尘螨疫苗。28只BALB/c小鼠按随机数字表法分为正常组(A组)、哮喘模型组(B组)、粉尘螨高剂量治疗组(C组)、粉尘螨低剂量治疗组(D组),每组7只。检测小鼠气道高反应性,观察支气管肺胞灌洗液(BALF)中细胞计数和分类,肺组织HE染色观察小鼠肺部炎症状况;通过免疫组织化学染色和体视学测量观察各组小鼠肺组织NF-κB阳性细胞的变化和颌下淋巴结33D1阳性DC的表达。结果 C组BALF中嗜酸性细胞计数、肺组织炎症细胞浸润较B组显著减少(P<0.05),气道高反应性下降(P<0.01)。C、D组哮喘小鼠颌下淋巴结33D1阳性DC和肺部NF-κB阳性细胞的数密度、体密度、表面积密度均下降,C组比D组下降更明显(P<0.01)。结论高剂量舌下含服粉尘螨疫苗治疗哮喘小鼠有显著疗效,与DC的免疫耐受和NF-κB的下调密切相关。

Objective To investigate the changes in dendritic cells（DCs） and NF-κB before and after sublingual therapy with dust mite vaccine,and to further compare the therapeutic effects of high doses of vaccine and low doses of vaccine in mice with allergic asthma.Methods Sublingual dust mite vaccine was prepared by route method.A total of 28 BALB/c mice were randomly divided into four groups： normal group（group A）,asthma model group（group B）,high doses of dust mite vaccine immunotherapy group（group C） and low doses of dust mite vaccine immunotherapy group（group D）,with 7 mice in each group.The changes in NF-κB positive cells in lung tissue and 33D1 positive DCs in submandibular lymph nodes after immunotherapy were analyzed by immunohistochemistry and stereology.Airway hyperreactivity was determined,cells contained in bronchoalveolar lavage fluid（BALF） were accounted and classified,and lung inflammation was assayed by HE staining.Results Compared with group B,eosinophil count in BALF,lung inflammatory infiltration and airway hyperreactivity significantly decreased in group C（P0.01）.Mice in group C and D displayed reduced number density,bulk density and surface area density of 33D1 positive DCs and NF-κB positive cells after immunotherapy,and the reduction in group C was more obvious than that in group D（P0.01）.Conclusion Sublingual therapy with dust mite vaccine can effectively alleviate the clinical symptoms in the mouse asthma model,and the mechanism is involved in the immunotolerance of DCs and down-regulation of NF-κB.