协同刺激分子B7-H3在重症肌无力患者外周血中的表达

目的:检测重症肌无力(MG)患者外周血中协同刺激分子B7-H3的表达,并探讨其临床意义。方法:收集35例MG患者和44例健康对照(HC)外周血标本,采用免疫荧光标记,流式细胞检测外周血单个核细胞模型B7-H3(mB7-H3)的表达,ELISA法检测MG和HC血浆中可溶性B7-H3(sB7-H3)的含量。结果:MG患者外周血T淋巴细胞、单核细胞和B淋巴细胞上mB7-H3低水平表达,与HC无差异;MG患者外周血sB7-H3浓度为(2.166±0.958)ng/mL,显著低于HC(3.379±0.768)ng/mL;全身型MG(GMG)sB7-H3的浓度为(1.664±0.699)ng/mL,低于眼肌型MG(OMG)(2.396±0.985)ng/mL;并发胸腺异常的MG sB7-H3浓度为(1.593±0.441)ng/mL,低于胸腺正常MG(2.364±1.014)ng/mL;MGsB7-H3含量与QMGS评分呈负相关(r=-0.4189,P=0.012);免疫细胞mB7-H3与血浆sB7-H3无相关性。结论:MG患者sB7-H3表达下调,与疾病严重程度相关;在不同病理类型MG患者体内存在差异性表达,提示该分子可能参与了MG的免疫病理进程。

Expression of B7-H3 costimulatory molecule in peripheral blood of myasthenia gravis patients

AIM: To reveal the clinical significance of B7-H3 costimulatory molecule in myasthenia gravis(MG) patients by analyzing membranous B7-H3(mB7-H3) and soluble B7-H3(sB7-H3) expressions.METHODS: We collected peripheral blood samples of 35 MG patients and 44 health controls(HC) and detected the expression of mB7-H3 on peripheral blood mononuclear cells(PBMCs) using flow cytometry.ELISA was performed to analyze the levels of sB7-H3 in plasma samples from MG patients and HC.RESULTS: There was no significant difference in the expressions of mB7-H3 on T lymphocytes,monocytes or B cells between MG patients and HC.However,the level of sB7-H3 from MG patients was(2.166±0.958) ng/mL,significantly lower than that from HC(3.379±0.768) ng/mL.The level of sB7-H3 in general MG(GMG) patients(1.664±0.699) ng/mL was lower than that in ocular MG(OMG) patients(2.396±0.985) ng/mL.In MG patients complicated with abnormal thymus,the level of sB7-H3 was(1.593±0.441) ng/mL,also lower than that in MG patients with normal thymus(2.364±1.014) ng/mL.In addition,a significant negative correlation was found between the levels of sB7-H3 and QMGS in MG patients(r=-0.4189,P=0.012),but sB7-H3 was not associated with mB7-H3 in MG patients.CONCLUSION: In MG patients,down-regulation of sB7-H3 is finely correlated to the severity of the disease.Its different expression levels in various types of MG patients indicate that this costimulatory molecule may be involved in the immunopathogenesis of MG.