Vet. Res. 37 (2006) 401-415
DOI: 10.1051/vetres:2006008

The sheep and cattle Peyer's patch as a site of B-cell development

Masahiro Yasuda^{a, b}, Craig N. Jenne^a, Laurie J. Kennedy^a and John D. Reynolds<sup>a

a</sup>  Immunology Research Group, Department of Cell Biology and Anatomy, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
^b  Department of Veterinary Anatomy, University of Miyazaki, Miyazaki, Japan

(Received 4 July 2005; accepted 15 November 2005; published online 14 April 2006)

Abstract - 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.

Key words: B-cell development / apoptosis / antibody diversity / selection / Peyer's patch

Corresponding author: John D. Reynolds reynolds@ucalgary.ca

© INRA, EDP Sciences 2006