中文摘要：

目的检测类风湿关节炎（ rheumatoid arthritis, RA）患者外周血CD19＋CD24hiCD38hi调节性B细胞（regulatory Bcells，Bregs）比例及功能的变化情况，初步探讨Bregs在RA发病中的作用。方法采用流式细胞染色方法检测健康对照组及RA患者外周血单核细胞（ peripheral blood mononuclear cell, PBMC）中CD19＋CD24hi CD38hiB细胞和CD4T细胞比例变化情况；活细胞荧光染料CFSE染色方法检测CD19＋CD24hiCD38hiB细胞对NaiveCD4T细胞增殖能力的影响；同时检测CD19＋CD24hiCD38hi B细胞分泌IL-10的能力及对CD4T细胞分泌IFN-γ能力的影响。结果与健康对照组相比，RA患者外周血CD19＋CD24hiCD38hiB细胞比例显著降低，而CD4T细胞比例显著升高，且随着病情严重程度升高，差异有统计学意义（P〈0．05）。功能研究显示，RA患者外周血CD19＋CD24hiCD38hiB细胞分泌IL-10水平显著降低（P〈0．01），且其抑制NaiveCD4T细胞增殖及分泌IFN-γ的能力均显著降低（P〈0．01）。结论RA患者外周血CD19＋CD24hiCD38hiB细胞分泌IL-10能力下降，导致免疫抑制功能降低，进而引起CD4T细胞比例升高和IFN-γ水平升高，影响RA病情进展。

英文摘要：

Objective To investigate the role of CD19 ＋ CD24hiCD38hi regulatory B （Breg） cells in the progression of rheumatoid arthritis （RA） , the proportion and function of Breg cells were detected in the peripheral blood of RA pa- tients. Methods Flow cytometry staining were used to detect the percentage of peripheral blood CD19 ＋ CD24hiCD38hi B cells and CD4 T cells from the healthy controls and RA patients;and the effects of CD19 ＋ CD24hiCD38hi B cells on the proliferative capacity of Naive CD4 T cells were detected by the live cell fluorescence dye CFSE labeling assay. The effects of CD19 ＋ CD24hicD38hi B cells on the ability to secret IFN-γ of CD4 T cells and the ability to secret IL-10 of CD19 ＋ CD24hi CD38hi B cells were also be detected. Results The proportion of the CD19＋ CD24hiCD38hi B cells in the peripher- al blood in RA patients was significantly decreased compared with the healthy group controls. However, the proportion of CD4 T cells in the RA patients was higher than those in healthy controls, and the differences were more significant with the progression of RA（P 〈 0.05 ）. Functional studies demonstrate that the ability to secret IL-10 of CD19 ＋ CD24hiCD38hi B cells was lower in the RA patients （P 〈 0.01 ）. Moreover, the ability to inhibit the proliferation and secretion capacity of Naive CD4 T cells was greatly decreased compared with healthy controls（P 〈 0.01 ）. Conclusion The ability to secrete IL-10 of CD19＋ CD24hiCD38hi B cells in the peripheral blood is reduced in the RA patients,leading to the impairment of the function of the immune suppression, and the increased proportion of CD4 T ceils in the peripheral blood with the rised levels of IFN-γ, and accelerate the progression of RA patients.