摘要：

目的 探讨重症肌无力患者外周血具有CD27和CD38表型的B细胞亚群表达变化。方法 观察对象均为2016年1月至2018年12月住院治疗的重症肌无力患者共43例，采用流式细胞术和三色荧光标记法检测其外周血CD27⁺CD38^-、CD27⁺CD38⁺、CD27^-CD38⁺和CD27^-CD38^-B细胞表达变化。结果 与正常对照者相比，重症肌无力患者外周血CD27⁺CD38^-和CD27⁺CD38⁺B细胞比例升高（P=0.000，0.000）、CD27^-CD38⁺B细胞比例降低（P=0.001）。其中，外周血CD27⁺CD38^-B细胞比例，全身型高于眼肌型（P=0.031）；CD27^-CD38⁺B细胞比例，合并胸腺瘤者低于无胸腺异常者（P=0.026）；CD27⁺CD38^-和CD27⁺CD38⁺B细胞比例，肌无力危象者高于非肌无力危象者（P=0.017，0.011）。经甲泼尼龙冲击治疗后，QMGS评分减少（P=0.012）、外周血CD27⁺CD38⁺B细胞比例降低（P=0.034）、CD27^-CD38⁺B细胞比例升高（P=0.006）；Spearman秩相关分析，QMGS评分与外周血CD27⁺CD38^-B细胞比例呈正相关（r_s=0.394，P=0.009）。结论 重症肌无力患者外周血中存在具有CD27和CD38表型的B细胞亚群，其表达变化与疾病严重程度相关，提示不同表型的B细胞亚群可能在重症肌无力的免疫机制和疾病进程中发挥不同作用。

关键词: 重症肌无力, B淋巴细胞亚群, 抗原,CD27, 抗原,CD38

Abstract:

Objective To investigate the clinical significance of peripheral B cell subsets with CD27 and CD38 phenotypes in myasthenia gravis (MG) patients. Methods Peripheral blood samples of 43 MG patients and 38 healthy controls from January 2016 to December 2018 were collected. Peripheral CD27⁺CD38^-, CD27⁺CD38⁺, CD27^-CD38⁺ and CD27^-CD38^-B cells were detected through flow cytometer and tricolor fluorescence labeling. Results Percentages of CD27⁺CD38^- and CD27⁺CD38⁺B cells were increased (P=0.000, 0.000), while percentage of CD27^-CD38⁺B cells was decreased in MG patients compared with those in controls (P=0.001). The percentage of CD27⁺CD38^-B cells was higher in generalized GMG patients than that in OMG patients (P=0.031). However, patients with thymoma had lower percentage of CD27^-CD38⁺B cells than that in patients with normal thymus (P=0.026). CD27⁺CD38^- and CD27⁺CD38⁺B cells were enriched in patients with myasthenic crisis compared with patients without crisis (P=0.017, 0.011). In addition, after treatment of methylprednisolone, the Quantitative Myasthenia Gravis Score (QMGS) was decreased (P=0.012), the CD27⁺CD38⁺B cells reduced (P=0.034) and CD27⁺CD38^-B cells elevated (P=0.006). Meanwhile, percentage of CD27⁺CD38^-B cells was postively correlated with disease severity in MG patients (r_s=0.394, P=0.009). Conclusions Abnormal changes of B cell subsets with CD27 and CD38 phenotypes were observed and closely associated with disease severity in MG patients. All of these findings suggested that aberrancy of B cell subsets may be involved in the progression of MG.

Key words: Myasthenia gravis, B-lymphocyte subsets, Antigens,CD27, Antigens,CD38