类风湿关节炎患者外周血单个核细胞唾液酸结合免疫球蛋白样凝集素-1的表达及与疾病活动度的关系

The expression of sialic acid-binding immunoglobulin-like lectin-1 on peripheral blood mononuclearcells and its relationship with disease activity in rheumatoid arthritis

目的观察唾液酸结合免疫球蛋白样凝集素-1（Siglec-1）在类风湿关节炎（RA）患者外周血单个核细胞（PBMCs）上的表达水平，并探讨其与RA疾病活动度的关系。方法分别采用流式细胞术及实时荧光定量反转录聚合酶链反应（RT-PCR）检测42例RA患者、28例骨关节炎患者和26名健康对照者外周血Siglec-1蛋白和mRNA表达，并将Siglec-1表达与28个关节疾病活动度评分（DAS28）以及超敏c反应蛋白（hs-CRP）作相关性分析。组间均数比较采用t检验，相关性分析采用Pearson相关分析。结果流式细胞仪检测发现，RA组Siglec-1阳性细胞占PBMCs比例为（15．2±7．6）％，明显高于骨关节炎组[（2．3±2．6）％]和健康对照组[（2．1±1．6）％，t值分别为8．615，8．661；P均〈0．01]，并且表达Siglec-1的细胞主要为单核细胞；RA组Siglec-1mRNA的相对表达量为（3．4±1．5），明显高于骨关节炎组（1．2±0.4）和健康对照组（1．0±0．4）（￡值分别为3．446，3．966；P均〈0．05）。而骨关节炎组和健康对照组之间Siglec-1蛋白和mRNA表达差异无统计学意义（P〉0．05）。此外，RA患者Siglec—1的表达与DAS28及hs-CRP均呈正相关（r值分别为0．89，0．48；P均〈0．01）。结论RA患者外周血PBMCs已经激活并高表达Siglec-1，Siglec-1可能作为无创性指标用于监测RA疾病活动度和炎症程度。

Objective To investigate the expression of sialic acid-binding immunoglobulin-like lectin- 1 （Siglec-1） in the peripheral blood mononuclear cells （PBMCs） in patients with rheumatoid arthritis （RA）, osteoarthritis （OA） and healthy controls and to explore the relationship between Siglec-1 expression and disease activity in RA. Methods Siglec-1 protein and mRNA levels were measured by flow cytometry and real-time quantitative reverse transcription-polymerase chain reaction （qRT-PCR） in 42 RA patients, 28 OA patients and 26 healthy controls, respectively. The correlation studies between Siglec-1 and disease activity score 28 （DAS28） or C-reactive protein were performed. T-test was used for comparisons between groups and Pearson＇s correlation test was used for correlation analysis. Results The percentage of Siglec-1 positive ceils of PBMCs in RA group [（15.2±7.6）%] was significantly higher than that in the OA group [（2.3 ±2.6）%] or healthy controls [（2.1±1.6）%, t=-8.615, 8.661; all P〈0.01 ]. And the major cell type in PBMCs that expressed Siglec-1 was monocytes. The relative Siglec-1 mRNA expression in PBMCs in the RA group （3.4：t：1.5） was also significantly higher than that in the OA group （1.2±0.4） or healthy controls [（1.0± 0.4）, t=3.446, 3.966; all P〈0.05]. But no significant differences of Siglec-1 protein and mRNA between the OA group andhealthy controls were found. Furthermore, positive correlations between Siglec-1 protein and DAS28 or hs-CRP were found in RA patients （r--0.89, P〈0.01; r=0.48, P〈0.01）. Conclusion PBMCs are activated which are characterized by elevated expression of Siglec-I in RA patients. Circulating Siglec-1 may be considered as a potential noninvasive biomarker for monitoring disease activity in RA.