鼻息肉组织和外周血中B细胞亚群和表型功能特征比较分析

Comparison of subpopulations, phenotypes and functions of B cells in nasal polyp tissues and PBMCs

目的比较鼻息肉组织和外周血中B细胞的亚群分布、表型及功能特征。方法分离鼻息肉组织浸润的单个核细胞和病人外周血PBMCs,流式细胞术分析其B细胞表面分子的表达;体外培养10 d后,ELISA法检测培养上清中免疫球蛋白(Ig)含量。结果鼻息肉浸润单个核细胞与外周血PBMCs相比,CD19+B细胞的比例无显著变化,但CD19+CD38highCD20+/-浆细胞的比例明显升高(P<0.05)。分析B细胞亚群表明,与PBMCs中B细胞相比,鼻息肉浸润B细胞中含有较高比例的记忆性B细胞和生发中心细胞,初始B细胞比例则较低(P<0.05)。鼻息肉浸润B细胞大都处于活化状态,CD69的水平明显高于PBMCs中B细胞。与PBMCs中B细胞相比,鼻息肉浸润B细胞表面IgG表达显著升高而IgM表达明显降低(P<0.05)。ELISA检测结果表明,未经刺激的鼻息肉浸润单个核细胞产生IgG、IgA和IgM含量与PBMCs相比均显著增加(P<0.05)。结论鼻息肉组织和外周血中B细胞亚群分布及功能特征均存在一定差别,本实验为进一步研究B细胞在鼻息肉病理机制中的作用提供了初步的实验依据。

In this study, we aimed to compare the subpopulations, phenotypes and functions of B cells in nasal polyp tissues and peripheral blood of patients. Firstly, nasal polyp-infiltrating mononuclear cells and PBMCs were isolated and the surface markers on B cells were assayed by flow cytometry（FCM）. The nasal polyp-infiltrating mononuclear cells and PBMCs were cultured for 10 days, and the production of immunoglobulins in supernatants was detected by ELISA. FCM analysis revealed that there was no significant difference in the ratio of B cells in nasal polyp-infiltrating mononuclear cells and PBMCs, but higher frequencies of CD19＋CD38highCD20＋/-plasma cells were existed in nasal polyp-infiltrating mononuclear cells（P〈0.05）. Compared with PBMCs, nasal polyp-infiltrating B cells demonstrated higher proportion of memory B cells and germinal center cells（GC cells）, but lower frequencies of na觙ve B cells（P〈0.05）. In addition, most of nasal polyp-infiltrating B cells were activated, and expressed higher levels of CD69 than B cells from PBMCs（P〈0.05）. Compared to PBMCs, the expression of IgG on nasal polypinfiltrating B cells was higher, but the expression of IgM was lower（P〈0.05）. ELISA analysis showed that nasal polyp-infiltrating mononuclear cells could produce more IgG, IgA and IgM than PBMCs（P〈0.05）. In conclusion,subpopulations, phenotypes and functional characteristics of B cells in nasal polyp tissue were different from that of PBMCs at some levels. And our data may facilitate the further study on the function of B cells in nasal polyp.