Peyer’s Patches: Organized Lymphoid Structures for the Induction of Mucosal Immune Responses in the Intestine

Abstract

Peyer’s patches (PP) comprise transmucosal clusters of lymphoid follicles overlaid with a specialized lympho-epithelium and consequently play a central role in the induction of mucosal immune responses in the gut. Despite considerable achievements in the last 3 decades, in our understanding of how PP are involved in the induction of immune responses, much remains to be learned about these major organized lymphoid organs. The history and current status of PP termed ‘the major inductive site of immune responses’ is reviewed. The present understanding of PP biology and function, taking into account their preferential and unique retention of immune competent cells at specific sites, is discussed.

BOARD-INVITED REVIEW: Porcine mucosal immunity of the gastrointestinal tract1

“…Islands of discrete, organized lymphoid tissue with areas populated by B and T lymphocytes located in the small intestine are known as Peyer's patches and have been thoroughly reviewed elsewhere (Mayrhofer, 1984;Heel et al, 1997;Makala et al, 2002). Unlike the adjacent absorptive epithelium, Peyer's patches are overlaid with a specialized follicle-associated epithelium.…”

Roles of M cells in infection and mucosal vaccines

“…2 M cells (membranous epithelial, microfold or microvillous cells), first observed in 1965, 3 are functional units constituting inductive sites of the intestinal mucosal immune system. In the human gastrointestinal tract, M cells are predominantly present on the follicle-associated epithelium (FAE) which overlies the dome structure of Peyer's patches (PPs) in the small intestine, 4 and have been identified in the crypt epithelium of human tonsils and adenoids 5 and colon and rectum of mice. 6 They are specialized epithelial cells of GALT, playing a crucial role in the intestinal immune system by sampling and uptake of antigens, and then transporting them from the gut lumen to the underlying immune system.…”

The effect of in vivo exposure to zearalenone on cytokine secretion by Th1 and Th2 lymphocytes in porcine Peyer’s patches after in vitro stimulation with LPS

“…Gut-associated lymphoid tissue is found in three major regions in the form of Peyer's patches, lymphoid tissue in the lamina propria and endothelial lymphocytes. Peyer's patches, which are distributed most abundantly in the ileum, are part of gut-associated lymphoid tissue, and they recognize antigens through M (microfold) cells in the surrounding epithelium (Makala et al 2002). Antigens penetrating Peyer's patches activate B and T lymphocytes.…”