The expression of sialic acid-binding immunoglobulin-like lectin-1 on peripheral blood mononuclear cells and its relationship with disease activity in rheumatoid arthritis / 中华风湿病学杂志

ABSTRACT

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 reversetranscription-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 cells 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±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 and healthy 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-1 in RA patients.Circulating Siglec-1 may be considered as a potential noninvasive biomarker for monitoring disease activity in RA.