去泛素化酶MYSM1调控人B细胞向浆细胞的分化

Deubiquitinase MYSM1 Regulates Differentiation of Human B Cells to Plasma Cells

目的:探讨去泛素化酶MYSM1对人B细胞向浆细胞分化的调控作用。方法:构建去泛素化酶MYSM1的干扰载体和过表达载体,包装相应慢病毒及对照慢病毒;经人外周血磁珠分选出的CD19^+B细胞;经慢病毒感染48 h后,LPS刺激诱导感染后的CD19^+B细胞向浆细胞分化。流式细胞术检测CD138表达,荧光定量PCR检测B细胞及分化过程中重要转录因子的表达变化。结果:干扰MYSM1表达后,B细胞向浆细胞分化比例显著升高(P<0.01),抑制浆细胞分化的转录因子Pax5和Bach2的表达水平显著下降(P<0.01),而促进浆细胞分化的转录因子Prdm1和Xbp1的表达水平显著升高(P<0.01)。相反,过表达MYSM1后,B细胞向浆细胞分化比例显著下降(P<0.01),抑制浆细胞分化的转录因子Pax5和Bach2的表达水平显著升高(P<0.01),而促进浆细胞分化的转录因子Prdm1和Xbp1的表达水平显著下降(P<0.01)。结论:去泛素化酶MYSM1负调控人B细胞向浆细胞的分化。

Objective:To study the regulatory effect of deubiquitinase MYSM1 on differentiation of B cells to plasma cells.Methods:The interfering and overexpression plasmids of MYSM1 were constructed and then the corresponding lentiviruses were packaged.Human CD19^+B cells were isolated from human peripheral blood with Miltenyi B cell isolation kit.Purified CD19^+B cells were transduced with lentiviruses and then treated with LPS,the CD138 expression was detected by flow cytometry.The expression of transcription factor was determined by quantitative PCR.Results:The differentiation of B cells to plasma cells was enhanced after interfering in MYSM1 expression.Quantitative PCR showed that mRNA levels of Pax5 and Bach2 in cells with interfering in MYSM1 were much lower than their counterpart(P<0.01),and mRNA levels of Prdm1 and Xbp1 in cells with interfering in MYSM1 were much higher than their counterpart(P<0.01).On the contrary,the differentiation of B cells to plasma cells was inhibited after the overexpression of MYSM1.Quantitative PCR showed that mRNA levels of Pax5 and Bach2 in cells with MYSM1 overexpression were higher than those in control cells(P<0.01),and mRNA levels of Prdm1 and Xbp1 in cells with MYSM1 overexpression were much lower than those in their counterpart(P<0.01).Conclusion:MYSM1 negatively regulates differentiation of human B cells to plasma cells.