重症肌无力患者胸腺组织中Bcl-2和Fas表达水平的研究

目的探讨凋亡相关基因Bcl-2、Fas(又称Apo-1抗原,CD95)在重症肌无力患者胸腺组织中的表达及其临床意义.方法通过免疫组化法,检测经手术治疗的56例重症肌无力患者的胸腺组织(31例胸腺增生、25例胸腺瘤)中Bcl-2、Fas的表达水平,并以25例正常胸腺组织(取自先天性心脏病手术中因显露视野需要而切除的胸腺组织)作为对照组.结果 Bcl-2在胸腺瘤、胸腺增生组织中的表达均高于对照组,差别有显著性意义(均P＜0.01),胸腺瘤和胸腺增生两组之间的Bcl-2表达水平差别无显著性意义(P＞0.05);Fas在胸腺瘤中的表达上升,明显高于胸腺增生组和对照组(均P＜0.01),胸腺增生组与对照组Fas表达水平差别无显著性意义(P＞0.05).结论 Bcl-2的高水平表达导致胸腺免疫异常,在重症肌无力的发生中起重要作用,而Fas在胸腺瘤的发生中起重要的作用.

The level of BCL-2 and FAS expression in thymic tissue of myasthenia gravis

Objective To evaluate clinical significance of expression level of apoptosis-associated genes, BCL-2 and FAS(Apo-1 antigen,CD95)in thymic tissue from the patients with myasthenia gravis. Methods Fifty six patients with myasthenia gravis (31 cases with hyperplastic thymus and 25 cases with thymoma) who underwent maximal thymectomy were included in the study. The clinical stages (Osserman classification) were stage I in 23, IIA in 8, IIB in 22 and III in 3. The normal thymic tissue from 25 patients with congenital heart diseases was used as controls. The expression of BCL-2 and FAS in the tissue of hyperplastic thymus, thymoma and normal thymus was detected by immunohistochemistry. Results Bcl-2 expression was significantly higher in thymic hyperplasia and thymomas compared with normal thymus(P<0.01 and P<0.01). Fas expression was significantly higher in thymomas than that in controls, and there was no difference between hyperplastc thymus and normal controls. The expression levels of Bcl-2 and Fas had no relation to age, gender, course of disease and Osserman classification. Conclusion It suggested that BCL-2 was a trigger in myasthenia gravis, and Fas was a essential factor in the course of thymoma concomitance myasthenia gravis.