Effect of pregnancy on endothelial progenitor cells in patients with rheumatoid arthritis and its mechanism / 中华风湿病学杂志

ABSTRACT

Objective:To investigate the effect of pregnancy on endothelial progenitor cells (EPCs) in patients with rheumatoid arthritis (RA) and its mechanism.Methods:The newly treated RA patients in our hospital from January 2016 to June 2018, were included in this study. According to pregnancy or not, patients were divided into simple RA group and RA pregnancy group. They were all female patients, 30 in each group. Immunohistochemical staining was used to detect the number of lymphocyte common antigen (LCA) + lymphocytes and CD68 + macrophages in synovial tissue, flow cytometry was used to detect the proportion of EPC and endothelial cells, and enzyme-linked immunosorbent assay(ELISA) was used to detect the concentrations of vascular endothelial growth factor (VEGF), stromal cell derived factor (SDF-1), interleukin (IL)-6 and IL-10 in EPC supernatant. T-test was used for the comprarison between the two groups, and single factor analysis of variancewas used for the comparison between multiple groups. Results:Immunohistoche-mical results showed that the number of CD68 + macrophages and LCA + lymphocytes in synovium of RA with pregnancy group was significantly lower than that of non-pregnant RA group. The results of ELISA showed that the concentration of human leucocyte antigen-G (HLA-G) in peripheral blood was (8.9±1.7) pg/ml in non- pregnant RA group and (396.7±89.6) pg/ml in RA pregnancy group, the difference beween the two groups was statistically significant ( t=4.329, P<0.01). The results of flow cytometry showed that the proportion of EPC in lymphocytes was (0.13±0.03)% in non-pregnant RA group and (0.76±0.09)% in RA with pregnancy group, the difference beween the two groups was statisti-cally significant ( t=6.671, P<0.01). The results of correlation analysis showed that the proportion of EPC in peripheral blood was positively correlated with HLA-G concentration ( r=0.886 1, P<0.01). In vitro experiments showed that HLA-G could promote the recovery of EPC paracrine and differentiation function in RA patients. Conclusion:Pregnancy can improve the number and biological function of EPC in patients with RA. HLA-G may play an important role in this process.