IgA肾病患者外周血B淋巴细胞β1,3半乳糖基转移酶及其分子伴侣mRNA的表达

Expression of β1,3 Galactosyltransferase mRNA and Cosmc mRNA in Peripheral B Lymphocyte of Patients with IgA Nephropathy

目的探讨IgA肾病患者外周血B淋巴细胞β1,3半乳糖基转移酶(β1,3GT)mRNA和其分子伴侣(Cosmc)mRNA表达水平与IgA肾病临床及病理的关系。方法 2006年5月-2007年2月在中山大学附属第一医院肾活检确诊为IgA肾病的23例患儿(IgA肾病组),按照病理分级分为Ⅰ级+Ⅱ级组(n=6)、Ⅲ级组(n=6)和Ⅳ级+Ⅴ级组(n=11)。同期本院非IgA肾病患儿10例为非IgA肾病组,本院体检健康儿童23例为健康对照组。3组儿童年龄、性别比较差异均无统计学意义。分离3组儿童外周血B淋巴细胞,提取RNA,应用实时荧光定量反转录-PCR检测外周血B淋巴细胞β1,3GT mRNA、Cosmc mRNA表达水平。结果 IgA肾病患儿外周血B淋巴细胞β1,3GTmRNA表达水平(0.88±0.17)与健康对照组(0.79±0.20)和非IgA肾病组儿童(0.84±0.21)比较差异均无统计学意义(P>0.05)。IgA肾病患儿外周血B淋巴细胞Cosmc mRNA表达水平(0.82±0.20)低于健康对照组(0.99±0.32)和非IgA肾病(1.03±0.25)(P<0.05)。IgA肾病患儿24h尿蛋白水平与外周血B淋巴细胞β1,3GT mRNA、Cosmc mRNA表达水平均呈负相关(Pa<0.05)。Ⅰ级+Ⅱ级组、Ⅲ级组、Ⅳ级+Ⅴ级组IgA肾病患儿外周血B淋巴细胞β1,3GT mRNA、Cosmc mRNA表达水平无统计学差异(Pa>0.05)。结论 IgA肾病患者外周血B淋巴细胞Cosmc mRNA表达水平降低,与临床表现密切相关。外周血B淋巴细胞Cosmc mRNA表达水平降低可能与IgA肾病的发病有关。

Objective To investigate the expression of β1, 3 galactosytransferase （β1,3GT）mRNA and Cosmc mRNA in peripheral B lymphocyte of children with IgA nephropathy, and the relationships of mRNA expression levels of β1, 3GT and Cosmc with the clinical and pathological features of IgA nephropathy.Methods From May.2006 to Feb. 2007,23 biopsy-proven IgA nephropathy patients in the First Affiliated Hospital of Sun Yat-Sen University were enrolled in IgA nephropathy group.The IgA nephropathy group was divided into 3 pathologic grade groups according to Lee pathologic grade： grade Ⅰ ＋ grade Ⅱ group（n=6）, grade Ⅲ group （n=6）, grade Ⅳ ＋ grade Ⅴgroup （n=11）. At the same time, 10 non-IgA nephropathy patients were enrolled in non-IgA nephropathy group（n=10）. And 23 healthy people were enrolled in healthy control group（n=23）. There were no significant difference in age and gender ratio among groups（Pa〉0.05）. Peripheral B lymphocytes were isolated,RNA were extracted from peripheral B lymphocytes. The mRNA expression levels of β1, 3GT mRNA and Cosmc mRNA were measured by real-time fluorescent quantitative reverse transcriptase polymerase chain reaction.Results The β1,3GT mRNA level in peripheral B lymphocyte from IgA nephropathy patients（0.88±0.17） was not significantly different from those in healthy control group （0.79±0.20） and non-IgA nephropathy patients（0.84±0.21） （P〉0.05）. Cosmc mRNA level in peripheral B lymphocyte from IgA nephropathy patients（0.82±0.20） was lower than those in healthy control group（0.99±0.32） and non-IgA nephropathy patients（1.03±0.25）（P〈0.05）.The 24-hour urine protein level of IgA nephropathy patients was negatively correlated with β1,3GT mRNA and Cosmc mRNA （Pa〈0.05）.β1,3GT mRNA and Cosmc mRNA levels had no significant difference among 3 renal pathological grade groups of IgA nephropathy patients（Pa〉0.05）.Conclusions Cosmc mRNA level in peripheral B lymphocyte from IgA nephropathy patients is downregulated. The downregulation of cosmc mRNA level is closely associated with clinical characteristics of IgA nephropathy. The downregulation of Cosmc mRNA level may be one of pathogenesis of IgA nephropathy.