Correlation between the distribution of peripheral blood monocyte subsets and the pathogenesis of rheumatoid arthritis / 中华检验医学杂志

ABSTRACT

Objective:This work aims to assess the distribution of peripheral blood monocyte subsets, the expression level of the functional markers in rheumatoid arthritis (RA) patients, and analyze the correlation between the above indexes and the onset of RA.Methods:Peripheral blood mononuclear cells were collected and isolated from 62 RA patients, 52 healthy control (HC) and 12 disease control group′s patients via density centrifugation. The enrolled patients were attended or underwent physical examination in East Hospital, Tongji University from June 2020 to December 2021. Monocytes could be classified into classical (CM), intermediate (IM) and non-classical (NCM). Then, the flow cytometry was performed to examine the distribution of monocyte subsets and the measure the expression level of human leukocyte antigen DR (HLA-DR), intracellular tumor necrosis factor α (TNF-α) in peripheral blood monocytes. The statistical methods in this study mainly include: Kruskal-Wallis H test, Chi-Square test, Mann-Whitney U test, Wilcoxon matched-pairs signed ranks test, Spearman correlation coefficient test and Logistic regression analysis. The diagnostic value of IM proportion in RA was analyzed by ROC curve. Results:The monocytes number and monocytes proportion in white blood cells were much higher in RA [0.40 (0.40, 0.50), 7.60% (5.97%, 8.53%)] and disease control [0.40 (0.40, 0.68), 8.20% (5.85%, 10.28%)] compared with HC [0.30 (0.30, 0.40), 5.80% (5.03%, 6.38%)] ( H=24.733, P<0.001; H=27.469, P<0.001). A statistic-significant difference was detected among the proportion of CM[85.49%(76.91%,89.21%),88.94%(86.36%,91.72%),90.26%(80.25%, 92.56%)],IM[11.65%(8.47%,17.89%),7.89%(5.36%,10.75%), 5.56%(4.17%, 8.27%)], NCM[2.22%(1.39%, 3.74%), 2.49%(1.74%, 4.66%), 5.13%(3.39%, 9.85%)] in RA group, HC group and disease control group ( H=11.389, P=0.003; H=20.815, P<0.001; H=10.640, P=0.005). The proportion of CM was lower in RA and the IM proportion was increased in RA( P=0.003; P=0.003). The intracellular TNF-α level of monocytes in all three groups revealed the trend that IM>NCM>CM. The intracellular TNF-α in IM of RA was positively associated with serum TNF-α ( r=0.376, P=0.041). The HLA-DR expression in IM subsets were higher than CM and NCM subsets in all RA,HC and disease control groups. The expression of HLA-DR of IM in RA group and disease control was higher than HC group [8 611.50 (6201.3, 9890.8), 10 295.0 (7 899.0, 13632.0), 6 278.00(4 057.8, 9522.0), H=10.495, P=0.005]. There were no correlations between the proportion of peripheral blood IM and clinical characteristics CRP ( r=0.119, P=0.359), RF ( r=0.204, P=0.112) and ESR ( r=0.153, P=0.236). Logistic regression analysis showed that the proportion of IM ( OR=1.169, 95% CI 1.003-1.363, P=0.046), CRP ( OR=1.277, 95% CI 1.000-1.631, P=0.050), RF ( OR=1.179, 95% CI 1.080-1.287, P<0.001) are positively correlated with RA onset. The area under ROC curve for diagnosis of RA with IM proportion was 0.687, and the 95% confidence interval was 0.590-0.784, P<0.001. Conclusions:The distribution of monocyte subsets in peripheral blood of RA patients is abnormal. The increase in the proportion of IM, the enhanced antigen-presenting ability, and the increased level of TNF-α secretion in RA patients may play an important role in the pathogenesis of RA.