脐带间质干细胞移植对Graves病小鼠调节性B细胞的影响

The effect of umbilical cord mesenchymal stem cells transplantation for the GD mice on regulatory B cells

目的探讨脐带间质干细胞(UC-MSCs)治疗Graves病(GD)小鼠的作用机制。方法 32只小鼠随机分为正常对照组(G0组)、GD对照组(G1组)和UC-MSCs治疗组(G2组)。留取小鼠血清,化学发光法检测血清游离甲状腺素(FT4)水平,酶联免疫吸附法检测甲状腺刺激抗体(TSAb)浓度。取甲状腺,制备石蜡切片行苏木精-伊红染色。取脾脏,部分制成单个核细胞悬液,行三标记免疫荧光染色、流式细胞分析CD1dhi CD5+CD19+Bregs比例;部分脾脏提取总RNA,实时荧光定量PCR检测Bregs相关细胞因子白细胞介素-10(IL-10)mRNA和转化生长因子-β(TGF-β)mRNA的表达水平。结果 26周时G2组血清中TSAb浓度与脾脏组织中CD19+B细胞较G1组明显降低(P<0.05),B细胞中CD1dhi CD5+CD19+Bregs所占比例和脾组织IL-10mRNA、TGF-βmRNA表达量较G1组却明显上升(P<0.05),且在移植前、后血清TSAb浓度差与脾脏中CD1dhi CD5+CD19+Bregs所占比例变化呈显著负相关,与IL-10、TGF-βmRNA的表达量变化呈显著正相关。结论 UC-MSCs可能通过上调Bregs表达而发挥治疗作用。

Objective To investigate the therapeutic mechanism of umbilical cord mesenchymal stem cell（UC-MSCs）trans-plantation for the graves disease（GD）mice .Methods Thirty two mice were divided into 3 groups as following ：normal control group （G0） ,GD control group （G1） ,UC-MSCs group（G2） .Enzyme linked immunosorbent assay（ELISA）was used to measure the level of TSAb in blood serum and the expression of FT4 was measured by chemiluminescence .Thyroid sections were stained with hema-toxylin and eosin（HE）for histological examination .Splenocytes were stained with multicolor immunofluorescence and detected by flow cytometry to analyze the percentages of CD1dhiCD5＋CD19＋ regulatory B cells（Bregs） .Expressions of IL-10 and TGF-βmR-NA in spleen organization were measured by Real-time PCR .Results At 26 weeks ,the level of TSAb in blood serum in G2 was more significantly decreased than in G1（P〈0 .05） ,and the level of CD19＋ B in spleen in G2 was also more significantly decreased than in G1（P〈0 .05） ,however ,the percentage of CD1dhiCD5＋CD19＋ Bregs splenocytes and the levels of IL-10 and TGF-βmRNA in spleen organization were more significantly increased than in G1（P〈0 .05） .The concentration differences of TSAb in serum was negatively correlated with the percentage differences of CD1dhi CD5＋ CD19＋ Bregs ,however ,positively correlated with the expres-sion differences of IL-10 and TGF-βmRNA in spleen before and after transplantation .Conclusion Activation of Bregs may be one of the mechanisms of UC-MSCs therapeutic effect on GD mice .