系统性红斑狼疮患者外周血单个核细胞T细胞受体重组删除环水平

A study of T cell recombination excision circles levels in peripheral blood mononuclear cells of systemic lupus erythematosus patients

目的 通过检测系统性红斑狼疮（SLE）患者外周血单个核细胞（PBMC）T细胞受体重组删除环（TREC）水平,探讨其与临床表现间的关系及SLE的发病机制.方法 收集21例SLE组患者和22例年龄、性别相匹配的健康对照组一般临床资料;采集2组受试者外周静脉血,分离PBMC,实时荧光定量PCR检测TREC水平,结果以＂TREC拷贝数/1000 PBMC＂表示.结果 SLE组患者外周血PBMC中TREC水平为（9.6±7.5）拷贝/1000 PBMC,明显低于健康对照组[（16.1±11.1）拷贝/1000 PBMC,P=0.033].健康对照组PBMC中TREC水平与年龄呈负相关（r=-0.614,P=0.002）,而SLE组无这种相关性.SLE组患者PBMC中TREC水平与SLEDAI评分呈负相关（r=-0.656,P=0.001）,与皮肤黏膜受累旱负相关（r=-0.620,P=0.003）,与其他临床表现及实验室指标无明显关联.结论 SLE患者外周血TREC水平降低提示SLE患者胸腺近期输出产物比例减少,这可能与该疾病造成胸腺近期输出功能减弱和（或）T细胞外周增殖增加有关.胸腺近期输出产物在外周T细胞池巾的含量减少,可能埘SLE患者免疫功能异常产生影响.

Objective To compare the T cell receptor recombination excision cycle （TREC） levels in peripheral blood mononuclear cells （PBMC） of systemic lupus erythematosus （SLE） patients with normal age- and gender- matched controls. To investigate the correlations between TREC levels of SLE patients and their clinical features. Methods We studied TREC levels in peripheral blood mononuclear cells （PBMC） of 21 SLE patients and 22 normal age- and sex- matched controls. TREC concentration was determined by real-time quantitative polymerase chain reaction （real-time qPCR） as the number of TREC copies/1000 PBMCs. The clinical features of the SLE patients such as systemic lupus erythematosus disease activity index （SLEDAI） , ESR, C reaction protein （CRP） , ANA, anti-dsDNA and complement levels and organ involvement were recorded and assessed. Results SLE patients had lower TREC levels [ （9.6 ± 7.5 ）copies/1000 PBMC] than controls[ （16.1 ±11.1） copies/1000 PBMC,P = 0.033]. There was an inverse correlation between age and TREC levels in controls （r =- 0. 614, P = 0. 002） but not in SLE patients.There was an inverse correlation between SLEDAI and TREC levels in SLE patients（r =-0. 656, P =0. 001） and TREC levels seemed to have relations to skin lesions （ r = - 0. 620, P = 0. 003 ）. No other clinical association was observed between TREC levels and clinical and laboratory SLE manifestations.Conclusion SLE patients had lower TREC levels than normal controls and there is a tendency that TREC level is reversely correlated with disease activity. The decrease PBMC TREC level is indicative of a low proportion of recent thymic emigrant （RTE） in SLE and could be caused by decreased RTE output and/or by increased peripheral T cell proliferation in this disease. The under-representation of RTE in the peripheral T cell pool may play a role in the immune tolerance abnormalities observed in SLE.