ABSTRACT
Objective To investigate the expression of T cell immunoglobulin and mucindomain-containing molecule-3 (TIM3) on PBMCs,and the plasma concentrations of soluble forms of Galetcin9 and their clinical relationship with rheumatoid arthritis (RA).Methods Peripheral blood samples were collected from 39 patients,25 osteoarthritis (OA) patients and 20 healthy subjects (HC).The expressions of TIM3 on peripheral blood mononuelear cells (PBMCs) were detected by flow cytometry.The concentrations of soluble Galetcin9 were assessed by enzyme linked immunosorbent assay (ELISA).And the relationship between their expression levels and clinical manifestations were analyzed.Levene F test was used for statistical analysis,normal distribution data were compared by t test and Pearson correlation analysis,while Mann-Whitney U test and Spearman correlation analysis were used for non-normal distribution data.Results The expression of TIM3 on CD4+ T cells was significantly higher than that of the HC [(14.7±3.2)％ vs (5.1±0.8)％,t=2.339,P=0.022 7],while there was no statistical difference between the RA group and the OA group [(14.7±3.2)％ vs (5.8±0.4)％,t=1.928,P=0.058 9].The expression of TIM3 was significantly correlated with the concentration of RF in the serum and the corresponding DAS28 score (r=0.325 8,P=0.043 0;r=0.407 5,P=0.010 0).The expression of TIM3 on CD8 + T cells in RA patients was significantly higher than that in the HC and OA [(21.1±3.4)％ vs (8.3±1.5)％,t=2.531,P=0.0142;(21.1±3.4)％ vs (10.7±1.0)％,t=2.314,P=0.024 0] which was significantly correlated with the concentration of RF in serum and the corresponding DAS28 score (r=0.451 5,P=0.003 9;r=0.524 1,P=0.000 6) as well.However,the expression of TIM3 on CD56+ NK cells was not significantly different from that of either OA or HC[(56.4±3.4)％ vs (50.6±3.8)％,t=1.047,P=0.299 8;(56.4± 3.4)％ vs (56.1±3.4)％,t=0.048,P=0.961 9],the concentration of serum RF and the corresponding DAS28 score were not significantly related.We also found that plasma Galectin 9 concentrations in RA patients were significantly higher than those of OA patients [(4.24±0.22) ng/ml vs (3.15±0.18) ng/ml,t=3.187,P=0.024] and healthy subjects [(4.24±0.22) ng/ml vs (2.55±0.14) ng/ml,t=5.567,P＜0.01],which was correlated with RF and DAS28 (r=0.479 2,P=0.002 0;r=0.353 0,P=0.027 5) while there was no correlation with CRP (r=0.176 3,P=0.283 1).Conclusion The upregulated expressions of TIM3 on peripheral lymphocytes and the high levels of plasma concentration of soluble Galectin 9 are closely correlated with the severity of the disease,suggesting that TIM3/Galectin 9 pathway may play a critical role in the pathogenesis of RA.