Peyer patches

Peyers patches are covered by epithelial cells which can differentiate into M cells. M cells play an important role in the immunologic surveillance of the gut and are involved in specific functions like transport of particles, antigens, macromolecules. M cells seem to be involve in the absorption of intact proteins (Walker and Sanderson 1992). Peyers patches have been studied for uptake of macromolecules. Their proximal vicinity to immunocompetent cells is another hurdle for industrial use as a preferred uptake route (Daugherty and Mrsny 1999 Neutra 1998). M cells have been used to study uptake of lectins (for overview, see Daugherty and Mrsny 1999). However both cell types - Peyers patches and M cells - clearly are limited in their use as a preferred uptake route due to a small surface area they are covering and the limited capacity of absorbed molecules. 

Epithelial cells covering the Peyers patches form the barrier in the intestine. 

Le Fevre, H.E. Joel, D.D. Shidlousky, G. Retention of ingested latex particles in peyers patches of gerinfree and conventional mice. Soc. Exp. Biol. Med. 1985, 179,... 

Frequent diarrheal stools, anorexia, increased fluid loss, ulceration, death of crypt cells and Peyers Patch lymphoid tissue... 

The ileum, a site that is responsible for a large part of the immune body response and where most of the Peyer patches are found in the mucous membrane, is considered an important site of probiotic... 

I.M. van der Lubben, J.C. Verhoef, A.C. V m Aelst, G. Borchard, and H.E. Junginger, Chitosan microparticles for oral vaccination Prepcuation, characterization md preliminary in vivo uptake studies in murine Peyers patches. Biomaterials, 22,687-694, 2001. 

Ruiz-Santana, S., Lopez, A., Torres, S., et al. (2001) Prevention of dexamethasone-induced lymphocytic apoptosis in the intestine and in Peyer patches by enteral nutrition. J Parenter Enteral Nutr 25, 338-345. 

NF-kB is also crucial for the proper functioning of the adaptive immune system not only by acting on the immune cells themselves but also by participating in the development and organization of the secondary lymphoid organs (lymph nodes, spleen, and Peyer s patches), in which both B and T lymphocytes undergo maturation and activation. NF-kB proteins have an important role in lymphocyte development and... 

A wide diversity of herbal remedies have purported abilities to stimulate defense functions. Complexes of carbohydrate and lignin, which are present in some herbs, modulate enteric immune functions (Kiyohara et al, 2000), and the changes in cytokine secretion (Matsumoto and Yamada, 2000) can trigger systemic responses. The polysaccharides present in other herbal medicines augment production of immunoglobulin (Ig) A by the Peyer s patches in the small intestine (Sakushima et al, 1997 Yu et al, 1998). The responses of the enteric immune system to lectins are variable (Pusztai 1993), and can elicit systemic responses (Lavelle et al, 2000). Other phytochemicals provide protection by inducing detoxification pathways in mucosal cells (Williamson et al, 1998). 

SAKUSHIMA J, NOSE M, OGiHARA Y (1997) Effect of hachimi-jio-gan on immunoglobulin A producing cells in Peyer s patch by oral administration. Biol Pharm Bull. 20 1175-7. 

M cell Microfold or membranous cell of Peyer s patch epithelium MCP Membrane co-factor protein MCP-1 Monocyte chemotactic protein-1... 

Gut-associated lymphoid tissue (GALT) Lymphoid tissue, including Peyer s patches, found in the gut that is important for providing localized immunity against pathogens. 

Mora JR, Bono MR, Manjunath N, et al. Selective imprinting of gut-homing T cells by Peyer s patch dendritic cells. Nature 2003 424 88-93. 

Although most drugs are absorbed from the intestine by the blood capillary network in the villi, they can also be taken up by the lymphatic system (an integral and necessary part of the vascular system, the function of which is to collect extra tissue fluid and return it to the vascular compartment), particularly by M cells that reside in the Peyer s patch regions of the intestine. Peyer s patches have also been implicated in the regulation of the secretory immune response. Wachsmann et al. [277] reported that an antigenic material encapsulated within a liposome, when administered perorally, is taken up by these M cells and exhibited better saliva and serum IgA (primary and secondary)... 

Figure 4 Epithelium overlying a human Peyer s patch and associated immunological and lymphoid cell regions. (From Ref. 77.)...

C Press, S McClure, T Landsverk. Computer-assisted morphometric analysis of absorptive and follicle-associated epithelia of Peyer s patches. Immunology 72 386-392, 1991. 

J. Kraehenbuhl, and E. Pringault. Conversion by Peyer s patch lymphocytes of human enterocytes into M cells that transport bacteria., Science 1997, 277, 949-952... 

Promote Peyer s patch Wall-lumen mixing... 

The main site of the mucosal immune system in the gut is referred to as gut-associated lymphoid tissue (GALT), which can be divided into inductive and effector sites. In the small intestine, the inductive sites are in the Peyer s patches, which consist of large lymphoid follicles in the terminal small intestine. The contact with external antibodies triggers a series of cascade events in the body based on immune response (Brandtzaeg et al., 1999). 

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