目的：观察全身型重症肌无力（myasthenia gravis, MG）患者血中T淋巴细胞亚群百分比的变化，分析其与患者症状加重或缓解间的关系。方法：采用流式细胞术分别检测51例全身型MG患者在病情加重及缓解的不同时期外周血中T淋巴细胞亚群百分比的变化，分析其与症状波动之间的关系，另设30名健康体检者为对照组。结果：加重期MG患者血中的CD4⁺CD25⁺CD127^low/-调节性T淋巴细胞和CD4⁺CD45RA⁺原始T淋巴细胞百分比均明显低于对照组（5.54%±1.88%比7.95%±3.45%，P<0.05;11.42%±6.97%比 24.98%±7.86%，P<0.05）;而MG患者加重期血中的CD4⁺CD45RO⁺T淋巴细胞百分比高于缓解期及对照组（35.06%±8.78%比30.82%±8.43%;35.06%±8.78%比30.09%±7.53%，P均<0.05）。采用受试者工作特征曲线（receiver operating characteristic curve，ROC曲线）分析淋巴细胞百分比在MG诊断中的价值，患者血中的CD4⁺CD25⁺CD127^low/-调节性T淋巴细胞和CD4⁺CD45RA⁺T淋巴细胞诊断全身型MG发病的ROC曲线下面积（area under curve，AUC）分别为0.713和0.900（P<0.05）;CD4⁺CD45RO⁺ T淋巴细胞诊断MG症状加重的AUC为0.675，其最佳临界值为32.06%。结论：检测调节性T淋巴细胞和CD4⁺CD45RA⁺T淋巴细胞百分比对全身型MG的发病具有一定诊断价值，而CD4⁺CD45RO⁺T淋巴细胞百分比与全身型MG患者的症状波动相关，有可能成为衡量其病情变化的标志物。

Objective: To investigate the relationship between changes of T lymphocytes and exacerbation and remission in patients with generalized myasthenia gravis (GMG). Methods: Flow cytometry was used to detect the change of T lymphocyte subsets in peripheral blood of 51 patients with GMG during different periods of exacerbation and remission, and analyzed the relationship between the changes of T lymphocytes and symptom fluctuations. Results: The percentage of CD4⁺CD25⁺CD127^low/-regulatory T lymphocytes and CD4⁺CD45RA⁺naive T lymphocytes was significantly lower in exacerbation period than that in control group (P<0.05), whereas the percentage of CD4⁺CD45RO⁺ memory T lymphocytes in exacerbation period was significantly higher than that in remission period and control group(P<0.05). The AUC of CD4⁺CD25⁺CD127^low/-regulatory T lymphocytes and CD4⁺CD45RA⁺naive T lymphocytes were 0.713 and 0.900, respectively. The AUC of CD4⁺CD45RO⁺ memory T lymphocytes in exacerbation period was 0.675 and the optimum critical value was 32.06%. Conclusions: Regulatory T lymphocytes and CD4⁺CD45RA⁺naive T lymphocytes have diagnostic value for GMG. CD4⁺CD45RO⁺ memory T lymphocytes are correlated with symptom aggravation and remission of GMG, and may be used as a marker for measuring the symptom fluctuation of myasthenia gravis.