Rig-I基因表达下降对成熟B细胞株的影响

The influence of the down-regulated expression or Rig-I gene on the differentiation of mature B cells

Rig-I是全反式维甲酸诱导NB4细胞分化过程的上调基因,可能与细胞分化有关。通过RNAi的方法,使一株B细胞株(1B4.B6.细胞株)的Rig-I下降,研究其下调后对该B细胞株的影响。结果表明Rig-I下调表达使1B4.B6.细胞株中的CD138单阳性细胞比例明显减少,B220单阳性和CD138+B220+双阳性细胞不同程度的升高,这可能与B细胞株分化成浆细胞有关,同时Rig-I下调使LPS刺激该细胞株产生IgG3的胚系转录本(germlinetranscript)的表达下调。提示Rig-I可能参与抗体类别转换。

Rig-I is the up-regulated gene in NB4 cells when it was induced by AIRA, and it may be involved in the processes of cell differentiation. By using the RNAi technology, the reduction of the Rig-1 gene expression in a strain of the B cell lines (1B4.B6 cell line) was possible, and after reduction of the gene expression, the influences on the differentiation of B cells were investigated in the present study. The experimental results showed that, in 1B4.B6 cell line, the percentage of the CD138 single positive cells was significantly decreased after reduced expression of the Rig-I gene, while that of the B220 single positive cells and the CD138+B220+ double positive cells was increased with different degrees. These results suggest that the Rig-I might be involved in the course of differentiation from B cells to plasma cells, and that the reduced expression of Rig-I gene would down-regulate the expression of IgG3 germline transcripts in 1B4.B6 cells during the stimulation of B cell lines with LPS, indicating that Rig-I gene is also involved in antibody class switch.