Roles of BCR signaling mediated by PLC-γ2 on memory response

为了阐明PLC-γ2在记忆反应中的作用，我们将PLC-γ2条件性基因敲除小鼠与表达Cre的小鼠杂交。在γ-Cre小鼠B细胞中，只有表达Cre重组酶的细胞表达Cre重组酶。因此，B细胞正常分化为成熟期，只有对抗原有反应并转为免疫球蛋白G_1+的B细胞表达cre重组酶，以取消PLC-γ-2的表达。这将使分析PLC-γ2在免疫球蛋白1记忆应答中的作用与其他免疫球蛋白类的应答相比较。我们首先检测了PLC-γ2基因在体外免疫球蛋白1开关细胞中是否有效缺失，并在我们建立的小鼠中发现了这种情况。另一项发现是，这些小鼠的IgG1滴度在这些小鼠中显著降低。这些结果有力地表明，PLC-γ2在记忆反应中起着关键作用。

We have crossed the PLC-γ2 conditional knock-out mice with IgG1-Cre expressing mice In order to clarify the roles of PLC-γ2 on memory response. In the B cells from IgG1-Cre mice, only the cells those express γ1 germline transcript express Cre recombinase. For this reason, B cells differentiate normally to mature stage and only those which responded to antigen and switched to IgG1+ express cre recombinase to abolish PLC-γ2 expression. This will make it possible to analyze the role of PLC-γ2 in the IgG1 memory response in comparison with response of other IgG class.We first examined whether PLC-γ2 gene is efficiently deleted in IgG1 switched cells in vitro or not, and found that it is the case in the mice we have established. Another finding is that IgG1 titer in those mice is markedly decreased in these mice. Together with these results, it is strongly suggested that PLC-γ2 is playing a pivotal role in memory responses.