SLE患者血清中的IL-6对造血干细胞来源的树突状细胞分化发育的影响

Effect of IL-6 in SLE serum on the differentiation and maturation of dendritic cells derived from hematopoietic precursor cells

目的:观察系统性红斑狼疮(systemic lupus erythematosus,SLE)患者血清中的IL-6对脐血CD34+造血干细胞(Hematopoietic precursor cells,HPCs)来源的树突状细胞(Dendritic cells,DCs)分化发育的影响。方法:免疫磁珠法(MACS)分离纯化脐血CD34+HPCs,GM-CSF+IL-4+TNF-α方案诱导其分化形成DCs。在培养过程中,分别加入正常人血清和IL-6水平升高的SLE血清,并通过IL-6抗体的中和作用,观察IL-6对DCs分化发育的影响。流式细胞术检测DCs表型(HLA-DR、CD80、CD86、CD83、CD1a),细胞增殖/毒性试剂盒(CCK-8)分析DCs刺激同种异体T细胞增殖的能力,酶联免疫吸附试验(ELISA)检测DCs分泌IL-12、IL-10、IFN-γ的水平。结果:SLE患者血清中的IL-6水平较正常人升高;在高IL-6的SLE血清作用下,脐血CD34+HPCs可分化形成不表达IL-10、IFN-γ的DCs,其HLA-DR、CD80、CD86的表达上调,刺激同种异体T细胞增殖的能力增强,但IL-12的分泌水平却有所下降。结论:SLE血清中显著升高的IL-6对CD34+造血干细胞来源的DCs的分化发育产生了异常影响,改变了DCs的特性,可能参与SLE的发生和发展。

Objective：To study the effect of IL-6 in SLE serum on the differentiation and maturation of dendritic cells（DCs） derived from cord blood CD34^＋ hematopoietic precursor cells （HPCs）. Methods：CD34^＋HPCs were isolated and purified from cord blood by magnetic cell sorting system（MACS）, and cultured with GM-CSF＋IL-4^＋TNF-α. Normal serum or SLE serum with high level of IL-6 was added into culture medium respectively. The phenotypes of DCs（HLA-DR,CD80,CD86, CD83 and CDla） were analyzed by FCM. Thcir abilities of stimulating allogenic T lymphocytes proliferation were examined by CCK-8, and ELISA was used to assess the IL-12, IL-10 and IFN-γ concentration in the culture supernatant. Results：The serum level of IL-6 was significantly higher in SLE patients than in controls. When cultured in SLE serum with high level of IL-6, CD34^＋HPCs could be induced to differentiate into DCs which produced little IL-10, little IFN-γ and lower IL-12, but expressed higher levels of HLA-DR, CD80 and CD86, and showed increased abilities of stimulating allogenic T lymphocytes proliferation compared with those cultured in normal serum. Conclusion： The high level of IL-6 in SLE serum has abnormal impacts on the differentiation and maturation of DCs and alters their characteristics, which may be involved in the initiation and maintenance of SLE.