IgA肾病患者腭扁桃体单个核细胞IgA类别转换基因表达变化  

Expression of IgA class switching gene in tonsillar mononuclear cells in patients with IgA nephropathy

作　　者：刘虹[1] 彭佑铭[1] 刘伏友[1] 肖薇薇[1] 李卫卫[1] 张俞[1] 刘洋[1] 

机构地区：[1]中南大学湘雅二医院肾内科湖南省肾脏病与血液净化学重点实验室中南大学肾脏病研究所,长沙410011

出　　处：《中华肾脏病杂志》2012年第2期83-88,共6页Chinese Journal of Nephrology

基　　金：基金项目：国家自然科学基金（81170663）

摘　　要：目的 研究脂多糖（LPS）或溶血性链球菌（HS）刺激IgA肾病和非肾脏疾病慢性扁桃体炎患者腭扁桃体单个核细胞Iα-Cα胚系转录本、激活诱导的胞嘧啶脱氨酶（AID）mRNA和蛋白的表达,以探讨IgA肾病腭扁桃体单个核细胞IgA及IgA1产生异常的分子机制.方法 入组2009年1月到2010年2月在我院住院的IgA肾病患者27例,非肾脏疾病慢性扁桃体炎患者27例作为对照.通过单个核细胞分离液和密度梯度离心法分离出腭扁桃体单个核细胞.IgA肾病组及非肾脏疾病慢性扁桃体炎组腭扁桃体单个核细胞分别分为3组：LPS刺激组,HS刺激组和未刺激组.ELISA法检测培养上清中IgA和IgA1的浓度.实时PCR检测Iα-Cα胚系转录本和AID mRNA的表达；Western印迹检测AID蛋白的表达.结果 IgA肾病组腭扁桃体单个核细胞IgA和IgA1的分泌,特别是IgA1/IgA较慢性扁桃体炎组显著增加（P＜0.05）,Iα-Cα和AID mRNA和AID蛋白的表达较慢性扁桃体炎组显著增加（均P＜0.05）.IgA肾病组腭扁桃体单个核细胞IgA和IgA1的水平在刺激后明显增加（P＜0.05）；Iα-Cα和AID mRNA的表达明显上调（均P＜0.05）；AID蛋白表达明显增加（LPS刺激组P＜0.05,HS刺激组P＜0.01）.结论 LPS和HS均能够诱导IgA肾病患者腭扁桃体单个核细胞IgA和IgA1的分泌、AID和Iα-Cα的表达增加,提示IgA肾病患者腭扁桃体IgA和IgA1的分泌增加可能与IgA类别转换相关基因AID和Iα-Cα高表达有关.Objec0tive To investigate the molecular mechanism of the mal-production of IgA and IgA1 by tonsillar mononuclear cells （TMCs） in IgA nephropathy （IgAN） patients by measuring the mRNA expression of Iα-Cα germline transcript and the mRNA and protein expression of activated induced cytidine deaminase （AID） in cultured TMCs stimulated with lipopolysaccharide （LPS） or hemolytic streptococcus （HS） in IgAN patients as well as the chronic tonsilitis patients. Methods Twent-seven IgAN patients admitted into our hospital from Jan.2009 to Feb.2010 were enrolled.Twent-seven patients with chronic tonsillitis without renal disease were selected as control.Tonsillar mononuclear cells were isolated by density gradient centrifugation in lymphocyte separation medium.The amount of IgA or IgA1 secreted in the culture supernatants was determined by specific enzyme-linked immunosorbent assay （ELISA）.Expressions of Iα-Cα germline transcript and AID mRNA were examined by real-time PCR.The AID protein was determined by Western blot. Results The production of IgA and IgA1 protein,especially the ratio of IgA1/IgA and the expression of AID protein in TMCs were significantly increased in IgAN group compared with chronic tonsillitis group （all P〈0.05）.The IgA and IgA1 level of stimulated TMCs were obviously increased in patients with IgAN compared with control group （P〈0.05）.And the expressions of Iα-Cα mRNA,AID mRNA and AID protein were up-regulated significantly in stimulated TMCs （all P〈0.05）. Conclusions Both LPS and HS can induce the production of IgA and IgA1 and up-regulate the expressions of AID and Iα-Cα in TMCs of IgAN patients.Our results indicate that the TMCs are capable of producing high level of IgA and IgA1 stimulated by LPS or HS,whuch may be due to the incression of AID and Iα-Cα.

关 键 词：肾小球肾炎 IGA 免疫球蛋白类别转换 扁桃体 胞嘧啶脱氨酶 胚系转录本 

分 类 号：R692.3[医药卫生—泌尿科学]