卵白蛋白介导白毛黑眼兔变应性鼻炎模型树突状细胞功能的改变

Functional changes of dendritic cells in the WHBE rabbits with allergic rhinitis induced by ovalbumin

目的比较观察卵白蛋白(OVA)诱导的白毛黑眼兔(WHBE兔)和日本大耳白兔(JW兔)变应性鼻炎(allergic rhinitis,AR)模型外周血来源树突状细胞(dendritic cells,DC)的功能,揭示WHBE兔对AR敏感的可能机制。方法以OVA诱导建立WHBE兔和JW兔AR模型,每次激发后观察动物一般体征,进行鼻黏膜HE染色,观察组织病理学改变。分离外周血DC,流式细胞仪检测外周血DC表面分子CD86的表达以及DC摄取抗原的能力,同时,采用荧光定量PCR检测外周血DC甘露糖受体(mannose receptor,MR)的mRNA表达水平。进一步以CFSE标记T细胞,流式细胞仪检测外周血DC诱导T细胞增殖能力。结果一般体征和HE染色观察显示,WHBE兔和JW兔模型组动物均表现为典型的变应性鼻炎症状和组织病理学改变,提示模型构建成功。WHBE兔AR模型组外周血DC CD86的表达不仅极显著高于正常对照组,亦极显著高于JW兔AR模型组(P<0.01,P<0.01)。正常稳态下,WHBE兔外周血DC MR的mRNA相对表达量极显著高于JW兔(P<0.01),经OVA诱发建立AR模型,WHBE兔外周血DC MR的mRNA表达水平显著升高(P<0.05),且显著高于JW兔模型组(P<0.05)。并且,WHBE兔模型组外周血DC摄取OVA647的能力极显著高于正常对照组(P<0.01),亦极显著高于JW兔模型组(P<0.01)。结论 WHBE兔DC对变应原更敏感,可能与其高表达抗原识别受体MR,具备更强的分化成熟、摄取抗原能力有关。

Objective To observe and compare the function of peripheral blood derived dendritic cells （DC） in white hair black eyes （WHBE） rabbits and Japanese white （JW） rabbits with allergic rhinitis （AR） induced by ovalbumin （OVA）,and to explore the mechanism of sensitivity to allergen in WHBE rabbits.Methods For the AR induction,rabbits were sensitized intraperitoneally everyday with OVA emulsified in Al（OH）3 followed from day 17 onward by 5 times nasal challenges with OVA in each nostril.General symptoms and histopathological changes of the nasal mucosa were observed.Expressions of CD86 on cell surface and antigen uptake of peripheral blood-derived dendritic cells were detected by flow cytometry at 6 days of culture.The mannose receptor （MR） mRNA expression was tested by real-time PCR.Proliferation of CFSE [5-（and 6-）-carboxyfluorescein diacetate succinimidyl ester]-labelled T cells stimulated by DC were observed by flow cytometry.Results The rabbits sensitized by OVA showed typical AR symptoms and pathological changes.Expressions of CD86 on the cell surface of dendritic cells in WHBE rabbits with AR were significantly upregulated not only compared with the normal control （NC） rabbits,but also with the JW rabbits with AR （P〈0.01）.The result of real-time PCR assay showed that MR mRNA expression of DC in the NC group of WHBE rabbits were significantly higher than that of the JWrabbits（P〈0.01）.Moreover,MR mRNA expression of DCs in the WHBE rabbits with AR were not only significantly higher than that in the NC rabbits （P〈0.05）,but also higher than that in the JW rabbits with AR （P〈0.05）.Meanwhile,OVA647 internalization percentages of DCs in the WHBE rabbits with AR were not only significantly higher than that in the NC rabbits,but also obviously higher than that in the JW rabbits with AR （P〈0.01）.Conclusions The sensitivity of WHBE rabbits to allergen may largely depend on the function of dendritic cells with high expression of mannose receptor and their strong ability of maturation and antigen uptake.