目的: 检测系统性硬化症(systemic sclerosis，SSc)患者血浆外泌体微小RNA(microRNA，miRNA)的表达，探讨其在SSc中的临床意义。方法: 选取20例梅州市人民医院风湿免疫科2020年1月至2022年1月未接受治疗的初诊SSc患者，同时以年龄及性别匹配的15例健康志愿者作为对照组。采用超速离心法获得血浆外泌体，采用实时荧光定量聚合酶链式反应(quantative real-time polymerase chain reaction, qRT-PCR)检测外泌体miR-34-5p、miR-92-3p和miR-142-3p的表达。采用Spearman秩相关系数检验分析miRNA表达水平与SSc临床特点的相关性。结果: 20例SSc患者的平均年龄为(52.6±12.6)岁，男性7例，女性13例。根据皮肤累及范围，13例为局限皮肤型SSc (limited cutaneous systemic sclerosis, lcSSc)，7例为弥漫皮肤型SSc (diffuse cutaneous systemic sclerosis, dcSSc)。根据高分辨率胸部CT检查结果，7例确诊间质性肺病(interstitial lung disease, ILD)，13例确诊非ILD。SSc患者血浆外泌体miR-34-5p、miR-92-3p和miR-142-3p的表达水平显著高于对照组(分别为P=0.003、P=0.000 1和P=0.016)。与未并发ILD的患者相比，并发ILD患者miR-34-5p和miR-142-3p的表达水平显著降低(分别为P=0.037和P=0.015)。miR-34-5p和miR-142-3p的表达水平与ILD(分别为r=-0.48、P=0.031和r=-0.55、P=0.011)、关节炎(分别为r=-0.46、P=0.040和r=-0.48、P=0.032)均呈负相关。miR-142-3p与红细胞沉降率呈负相关(r=-0.55、P=0.012)。结论: SSc的血浆外泌体miR-34-5p、miR-92-3p和miR-142-3p存在表达失调，表达异常的miR-34-5p和miR-142-3p与SSc相关ILD(SSc associated ILD, SSc-ILD)存在相关性。

Objective: To detect the expression of plasma exosomal microRNA (miRNA) in systemic sclerosis (SSc), and to investigate its clinical significance. Methods: A total of 20 patients who were initially diagnosed with SSc and did not receive medication in Department of Rheumatology and Immunology of Meizhou People' s Hospital from January 2020 to January 2022 were recruited, as well as 15 healthy individuals whose gender and age matched with those of the SSc patients. Plasma exosomes were isolated using ultracentrifugation method. The expression levels of exosomal miR-34-5p, miR-92-3p and miR-142-3p were detected by quantative real-time polymerase chain reaction (qRT-PCR). Correlations between the expression levels of exosomal miRNAs and clinical characteristic were analyzed by Spearman's rank correlation coefficient test. Results: The mean age of 20 patients with SSc was (52.6±12.6) years, including 7 males and 13 females. Among the 20 SSc patients, 13 cases were diagnosed as limited cutaneous systemic sclerosis (lcSSc) and 7 cases were diagnosed as diffuse cutaneous systemic sclerosis (dcSSc) according to the extent of skin involvement. According to the findings of high resolution chest CT, 7 of 20 SSc patients were diagnosed with interstitial lung disease (ILD) and 13 SSc patients were diagnosed with non-ILD. The expression levels of exosomal miR-34-5p, miR-92-3p and miR-142-3p were significantly elevated in the SSc patients compared with those in the healthy controls group (P=0.003, P=0.000 1, and P=0.016, respectively). Compared with the SSc patients without ILD, the expression levels of miR-34-5p and miR-142-3p were significantly lower in the SSc patients with ILD (P=0.037 and P=0.015, respectively). The expression levels of exosomal miR-34-5p and miR-142-3p showed negative correlation with ILD (r=-0.48, P=0.031 and r=-0.55, P=0.011, respectively), and arthritis (r=-0.46, P=0.040 and r=-0.48, P=0.032, respectively). The expression levels of exosomal miR-142-3p showed a negative correlation with erythrocyte sedimentation rate (ESR) (r=-0.55, P=0.012). Conclusion: Plasma exosomal miR-34-5p, miR-92-3p and miR-142-3p were dysregulated in SSc. The dyregulation of exosomal miR-34-5p and miR-142-3p showed correlation with SSc associated ILD (SSc-ILD).