水分子通道蛋白-5在干燥综合征唇腺中的异常表达

Abnormal expression of aquaporin-5 in labial glands of Sjogren′s syndrome patients

目的研究干燥综合征(Sj觟gren'ssyndrome,SS)患者唇腺中水分子通道蛋白-5(aquaporin5,AQP5)mRNA和蛋白表达水平的改变。方法收集50例SS和20例对照组(非结缔组织病患者13例和无SS的结缔组织病患者7例)的唇腺活检标本。①提取唇腺组织中的总RNA,用反转录聚合酶链反应(RT-PCR)方法共扩增AQP5和3-磷酸甘油醛脱氢酶(glyceraldehyde3-phosphatedehydrogenase,GAPDH)的片段,计算AQP5/GAPDH吸光度(A)比值。②利用亲合纯化的山羊抗人AQP5抗体,将唇腺组织切片进行免疫组织化学染色,计算AQP5阳性腺泡率。③将各组结果进行Mann-Whitney检验,并与临床检验结果进行相关性分析。结果原发性干燥综合征患者唇腺中AQP5在mRNA水平的表达,与非结缔组织病组相比明显升高(P<0.05),并与疾病病程呈正相关。SS患者,特别是原发性干燥综合征患者唇腺腺泡细胞腔面AQP5蛋白的表达,与非结缔组织病组相比明显降低(P<0.05),并与唇腺淋巴细胞浸润灶评分呈负相关。结论SS患者唇腺AQP5的表达异常,提示在SS发病机制中,AQP5的转录、转运过程中某些环节可能发生了改变。

Objective To investigate the mRNA transcription and protein expression of aquaporin-5（AQP5） in labial glands of Sjoegren＇s syndrome patients. The correlation of the results with the clinical manifestations and the possible role of AQP5 in the pathogenesis of Sjoegren＇s syndrome was analyzed. Methods The biopsy specimens from Sjoegren＇s syndrome and control patients were collected in the stomatological clinic of Peking Union Medical College Hospital.①The mRNA expression level tested by the RT-PCR and ②the expression of AQP5 in the labial gland acini on slides were compared. ③The correlation of clinical manifestation with the AQP5 expression was analyzed. Results ①The mRNA transcription level of AQP5 in labial glands in primary Sjoegren＇s syndrome patients was increased statistically （P=0.046）, compared to that in non-connective-tis-sue-disease patients.②The AQP5 distributed on the luminal membrane of labial gland acini from Sjoegren＇s syndrome patient, especially the primary Sjoegren＇s syndrome patients, was decreased statistically （P〈0.05） compared to that in non-connective-tissue- disease controls.③The mRNA transcription of AQP5 in labial glands from Sjoegren＇s syndrome patients was positively correlated with the disease course, and the Pearson＇s correlation coefficient was 0.60 （P=0.008）. ④The AQP5 distributed on the luminal membrane of labial gland acini from Sjoegren＇s syndrome patient＇s was negatively correlated with the lymphocyte focus-score, and the Pearson＇s correlation coefficient was -0.36 （P=0.03）. Conclusion The increased transcription of AQP5 mRNA and decreased expression of AQP5 protein in labial glands from primary Sjoegren＇s syndrome patients suggests that the change in transcription and transportation of AQP5 may play a role in the pathogenesis of Sjoegren＇s syndrome.