Development of therapeutic strategy for allergic diseases based on the genome information

我们前期的研究发现，IL-4基因在CD 4 ^+ T细胞中的表达受到表观遗传学的调控。然而，这些基因调控机制实际上是不清楚的。因此，我们使用GFP报告基因转基因（Tg）小鼠研究了IL-4和KIF 3基因之间基因间区域中进化上保守的约200 bp非编码序列的作用。Notch信号已被证明在多细胞生物体的整个生命过程中影响组织的细胞分化。RBP-Jκ是Notch信号转导中下游共同的转录介质。RBP-J□的T细胞特异性缺陷导致Th 2发育的选择性丧失。IL 4基因3'端增强子与保守非编码序列（CNS）-2相关，含有多个可能的RBP-Jκ结合位点。使用转基因GFP报告系统，我们发现RBP-Jκ与CNS-2增强子的结合调节了NKT细胞和CD 44<hi>记忆表型（MP）CD 4 T细胞亚群的初始IL-4产生。Rbp-j缺陷型T细胞表现出CNS-2增强子活性和来自NKT和MP CD 4 T细胞的初始IL-4的显著降低。CNS-2活性CD 4 T细胞的耗竭显著降低了初始CD 4 T细胞的Th 2分化。这些结果表明Notch信号和MP CD 4 T细胞在抗原诱导的过敏反应的初始阶段促进初始CD 4 T细胞的Th 2分化中的功能重要性。

From our previous study, the expression of IL-4 gene is found to be epigenetically regulated in CD4^+ T cells. However, these gene regulation mechanisms are virtually unclear. Therefore, we investigated the role of an evolutionarily conserved 〜200bp non-coding sequence in the intergenic region between IL-4 and KIF3 genes using GFP reporter transgenic (Tg) mice. Notch signals have been shown to affect the cellular differentiation of tissue throughout the life of multicellular organisms. RBP-Jκ is a downstream common transcriptional mediator in Notch signaling. The T cell specific deficiency of RBP-J□ resulted in selective loss of Th2 development. Distal 3' enhancer in Il4 locus that correlates with the conserved regions called, Conserved non-coding sequences (CNS)-2, contained multiple possible binding sites for RBP-Jκ. Using a transgenic GFP reporter system, we showed that binding of RBP-Jκ to the CNS-2 enhancer regulated initial IL-4 production from NKT cells and a subset of CD44^<hi> memory phenotype (MP) CD4 T cells. The Rbp-j deficient T cells exhibited marked reduction of both CNS-2 enhancer activity and initial IL-4 from NKT and MP CD4 T cells. Depletion of CNS-2 active CD4 T cells markedly decreased Th2 differentiation from naive CD4 T cells. These results indicate the functional importance of Notch signal and MP CD4 T cells in facilitating Th2 differentiation of naive CD4 T cells during initial stage of antigen induced allergic responses.