HDL suppresses dendritic cell maturation and modulates CD4+ T cell subtypes against inflammatory in a mouse model of rheumatoid arthritis

Abstract Background: To investigate the mechanism of anti-inflammatory effect of High-density lipoprotein (HDL) in collagen-induced arthritis (CIA) mice. Methods: The CIA animal model was constructed, and the mice were separated into three groups: control, CIA and CIA + HDL. In the CIA + HDL group, HDL was given on day 40, and an additional injection was administered every 3 days for a total of five doses. The levels of mouse HDL were measured by using ELISA kits, and liver, heart, kidney and colon tissue sections were stained with H＆E. Additionally, the splenic CD4+ T cell phenotypes in each group were analyzed. Immature DCs were stimulated with LPS in the presence or absence of HDL, and the expression of surface markers was investigated by FACS. Results: HDL decreased the ratio of Th1/Th2 cells and increased the Th1/Th17 cell ratio in the CIA + HDL group compared with those of the CIA one (P<0.05). In vitro, the expression of MHC-II, CD86, and CD40 in CD11c+ BMDCs was suppressed by HDL. The level of HDL in the CIA group was significantly reduced compared with that of the control one (P<0.05), and there were no significant pathological changes in the liver, heart, kidney and colon tissues of the mice among the three groups. Conclusion: HDL exerts anti-inflammatory effect in CIA mice by suppressing DCs maturation and modulating CD4+ T cell subtypes.