Yasuda Masahiro, Jenne Craig N, Kennedy Laurie J, Reynolds John D
Immunology Research Group, Department of Cell Biology and Anatomy, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada.
Vet Res. 2006 May-Jun;37(3):401-15. doi: 10.1051/vetres:2006008. Epub 2006 Apr 14.
In sheep and cattle, the ileal Peyer's patch (PP), which extends one-two meters along the terminal small intestine, is a primary lymphoid organ of B-cell development. B-cell diversity in the ileal PP is thought to develop by combinatorial mechanisms, gene conversion and/or point mutation. These species also have jejunal PP that function more like secondary lymphoid tissues concerned with mucosal immune reactions. These two types of PP differ significantly in their histology, ontogeny and the extent of lymphocyte traffic. The prenatal development of follicles in the PP begins first in the jejunum during the middle of gestation and then in the ileum during late gestation. B-cells proliferate rapidly in the ileal PP follicle; up to five percent of these cells survive while the majority dies by apoptosis, perhaps driven by the influence of environmental antigen and/or self-antigen. The surviving cells migrate from the ileal PP and populate the peripheral B-cell compartment. By adolescence, the ileal PP has involuted but the function of jejunal PP, compatible with a role as secondary lymphoid organ, continues throughout life. In this review, we focus on the development of PP as a site of B-cell repertoire generation, positive and negative B-cell selection, and the differences between ileal PP and jejunal PP.
在绵羊和牛中，回肠派尔集合淋巴结（PP）沿末端小肠延伸1至2米，是B细胞发育的主要淋巴器官。回肠PP中的B细胞多样性被认为是通过组合机制、基因转换和/或点突变形成的。这些物种也有空肠PP，其功能更类似于与黏膜免疫反应相关的二级淋巴组织。这两种类型的PP在组织学、个体发生和淋巴细胞迁移程度上有显著差异。PP中滤泡的产前发育首先在妊娠中期的空肠开始，然后在妊娠后期的回肠开始。B细胞在回肠PP滤泡中迅速增殖；其中高达5%的细胞存活下来，而大多数细胞通过凋亡死亡（可能是受环境抗原和/或自身抗原的影响）。存活的细胞从回肠PP迁移并填充外周B细胞区室。到青春期时，回肠PP已退化，但空肠PP作为二级淋巴器官的功能在整个生命过程中持续存在。在这篇综述中，我们重点关注PP作为B细胞库产生位点的发育、B细胞的阳性和阴性选择，以及回肠PP和空肠PP之间的差异。
