Fut8基因通过促进VLA-4/VCAM-1表达影响B细胞发育

Fut8 gene affects the development of B cells by regulating the core fucosylation of VLA-4/VCAM-1

目的探讨核心岩藻糖基化修饰对VLA-4/VCAM-1表达及B细胞发育的影响。方法通过RNA干扰技术使前B细胞(70Z/3)和基质细胞(ST2)的Fut8基因沉默,免疫沉淀和Western blot检测Fut8基因沉默效率,以细胞黏附实验和克隆形成实验分别研究Fut8基因对VLA-4/VCAM-1之间亲和力和对B细胞分化发育的影响。结果 Fut8基因沉默使VLA-4/VCAM-1之间的亲和力以及前B细胞和基质细胞之间的黏附作用降低,并使前B细胞的克隆形成能力明显下降。流式细胞仪分析结果也表明,Fut8-/-祖B细胞向前B细胞分化过程受阻。结论本实验揭示了Fut8基因调节VLA-4/VCAM-1之间结合能力以及前B细胞克隆形成的机理,为B细胞分化发育研究提供理论依据。

The aim of this study is to explore the role of fucosyhransferase Ⅷ （Fut8） in VLA-4/VCAM-1 expression and B cell development. Firstly, Fut8-knockdown 70Z/3 cells and Fut8-knockdown ST2 cells were established by RNA inference using 70Z/3 cells （pre-B cell line） and ST2 cells. Then Fur8 gene-silencing effects were detected by Western blot. In cell adhesion assays and colony forming tests, we found that the loss of a core fucose in both very late antigen 4 （VLA-4） and vascular cell adhesion molecule 1 （VCAM-1） would lead to a decreased binding between pre-B cells and stromal cells, followed the impaired pre-B cells generation in Fur8^＋mice. Flow cytometry analysis revealed that Fut8 expression was extremely required for regulating pre-B cell reproduction. These findings clearly demonstrated that the Fur8 could regulate the VLA-4/VCAM-1 interaction and the proper transition from pro-B to pre-B cells, showing the important role of Fur8 in B cell differentiation and development.