中文摘要：

目的研究结缔组织病（CTD）患者血浆白细胞介素（IL）-9水平及其与结缔组织病相关间质性肺疾病（ETD-ILD）患者的关系，探讨其含量异常在该类疾病中的意义。方法选择健康体检者20名，CTD患者61例，其中系统性硬化病（SSc）患者19例、类风湿关节炎（RA）患者15例、皮肌炎（DM）患者14例及系统性红斑狼疮（SLE）患者13例，根据有无合并ILD，将CTD患者分为CTD—ILD组29例及单纯CTD组32例，采用酶联免疫吸附试验（EHSA）检测各组血浆IL-9、IL-4及干扰素．1水平，比较其在各组中的差异，3组间的比较采用方差分析，3组中的两两比较采用Dunnett-t检验，计数资料采用χ2检验，相关分析采用非参数Spearman相关分析。结果3组血浆中IL．9水平（79±17，38±10，14±6）pg/ml差异有统计学意义（F=6．687，P=0．002），血浆IL-9水平在单纯CTD组（38±10）pg/ml及CTD-ILD组（79±17）pg/ml均高于健康对照组（14±6）pg/ml（f=2．115，P〈0．05；t=3．476，P〈0．01），CTD—ILD组明显高于CTD组（t=2．460，P〈0．05），血浆IL9水平与CTD患者干扰素-γ水平、用力肺活量值及一氧化碳弥散量值呈负相关（r=-0．58，-0．60，-0．52，P均〈O．05），与IL-4水平呈正相关（r=0．56，P〈0．05）。结论IL-9可能参与CTD的发病，并可能在CTD患者肺间质损害过程中发挥重要作用。

英文摘要：

Objective To investigate the level of interleukin （IL）-9 in patients with connective tissues disease （CTD） and connective tissue disease with interstitial lung disease （CTD-ILD）, and explore the role of IL-9 in the pathogenesis of CTD and CTD-ILD. Methods Sixty-one hospitalized untreated CTD patients were recruited and 20 healthy volunteers were enrolled as healthy controls. Patients in the CTD group included 19 systemic sclerosis （SSc） patients, 15 rheumatoid arthritis （RA） patients, 14 dermatomyositis （DM） patients, 13 systemic lupus erytbematosus （SLE） patients, 61 patients with CTD were divided into two groups, 32 cases with simple CTD and 29 CTD patients complicated with ILD （CTD-ILD group）. Plasma protein levels of IL-9, IL-4 and IFN-γ were measured by enzyme-linked immunosorbent assay （ELISA）, the differences between the groups were analyzed. Analysis of variance （ANOVA） was applied for data analysis between the three groups, pair-wise comparison was performed with Dunnett-t-test. For counting data, chi-square test was used for analysis. Non-parameterical Spearman＇s analysis was used for correlation analysis. Results There were significant differences among the three groups （79±17, 38±10, 14±6） pg/ml （F=6.687, P=0.002）, the serum IL-9 levels were increased in the CTD-ILD group （79±17） pg/ml arid the CTD group （38±10） pg/ml compared with healthy controls （14±6） pg/ml （t=2.115, P〈0.05, t=3.467, P〈0.01）, and it was higher in CTD-ILD group than in CTD group （t=2.460,P〈0.05）. Serum IL-9 levels were negatively correlated with the level of IFN-γ FVC % and DLCO %, and were positively correlated （r=-0.58, -0.60, -0.52, P〈0.05 for each） with the level of IL-4 （r=0.56, P〈0.05）. Conclusion IL-9 may play an important role in the pathogenesis of CTD, and may contribute to the progression of interstitial lung injury in CTD patients.