系统性红斑狼疮患者外周血白细胞介素9及CD4＋白细胞介素9＋T细胞的变化及其意义

Abnormality and significance of interleukin-9 and CD4 interleukin-9 T-cells in peripheral blood of patients with systemic lupus erythematosus

目的研究系统性红斑狼疮（SLE）患者外周血中自细胞介素（IL）9mRNA、IL-9蛋白水平以及CD4＋IL-9＋T细胞百分比及其与临床指标的相关性，并观察糖皮质激素治疗对血浆IL-9水平及外周血CD4＋IL-9＋T细胞百分比的影响。方法采用实时荧光定量聚合酶链反应（real—timePCR）、酶联免疫吸附试验（ELISA）及流式细胞学分别检测28例SLE患者及12名健康体检者外周血中IL-9mRNA、IL-9蛋白水平及CIM＋IL-9＋T细胞百分比，比较其在各组中的差异并分析糖皮质激素治疗对其的影响。结果（1）SLE患者外周血IL-9mRNA的表达明显高于健康对照组（P〈0．01）；SLE活动组患者血浆IL-9水平及缓解组血浆IL-9水平均明显高于健康对照组[（68±11）ng／L、（56±14）ng／L比（26±6）ng／L，P〈0．01及P〈0．05]；SLE活动组患者外周血中CD4＋IL-9＋T细胞百分比明显高于健康对照组和缓解组（1．96％±0．31％比0．28％±0．05％、0．89％±0．13％，均P〈0，01），缓解组亦高于健康对照组（P〈0．05）；（2）血浆IL-9水平和外周血CD4＋IL-9＋T细胞百分比均与SLE活动性指数（SLEDAI）呈正相关；（3）初发活动期SLE患者在接受甲泼尼龙（0．8nag·kg～·d“）治疗后第1、2、3周血浆IL-9水平及外周血CD4＋IL-9＋T细胞百分比均低于治疗前。结论IL-9及CD4＋IL-9＋T细胞可能在SLE的发病中起着重要作用，其含量异常可反映SLE的活动性及严重程度。

Objective To examine the protein and mRNA levels of interleukin-9 （IL-9） and the frequencies of CD4 ＋ IL-9 ＋ T-cells in peripheral blood of patients with systemic lupus erytbematosus （ SLE ） and explore the roles of double positive T cells and IL-9 in the pathogenesis of SLE and the effects of glucocorticoid. Methods Twenty-eight hospitalized SLE patients were recruited and 12 healthy volunteers selected as normal controls. The mRNA levels of IL-9 in peripheral blood were measured by real timepolymerase chain reaction （RT-PCR）, plasma protein of IL-9 by enzyme-linked immunosorbent assay （ELISA） and frequencies of CD4 ＋ IL-9 ＋ T-cells by flow cytometry. And the differences between two groups and the effects of glucocortieoid were analyzed. Results （ 1 ） The mRNA levels of IL-9 were significantly elevated in SLE patients as compared with normal controls （ P 〈 0. 01 ）. The serum levels of IL-9 were significantly higher in active and inactive SLE patients than those in healthy individuals （ 68 ＋ 11 vs 26 ＋ 6 ng/L, P 〈 0.01 ; 56 s 14 vs 26 s 6 ng/L, P 〈 0.05 ）. The percentages of CD4 IL-9 ＋ T-cells increased in active SLE patients （1.96% s0.31% ） versus inactive SLE patients （0.89% s0.13%, P 〈0.01 ） and healthy controls （0.28% s0.05%, P 〈 0. 001 ）. And it was higher in inactive SLE patients than that in controls （ P 〈 0.05 ）. （ 2 ） The serum levels of IL-9 and the frequencies of CIM ＋ IL-9 T-cells were positively correlated with SLE disease activity index （SLEDAI）. （ 3 ） The frequencies of CD4 ＋ IL-9 ＋ T-cells and the serum levels of IL-9 in 8 untreated active SLE patients decreased at weeks 1, 2 and 3 after the therapy of methylprednisolone （0.8 mg . kg-l . d-l） versus those at pre-treatment. Conclusion The abnormalities of IL-9 and CD4 IL-9 T-cells may play an important role in the pathogenesis of SLE. And thefrequencies of CIM IL-9 T-cells and the levels of IL-9 are evaluative parameters of SLE activity and severity.