Peyer’s patches, M cells

It is well known that intestinal M cells have the ability to efficiently transcytose macromolecules and inert particles, which has stimulated researchers to target M cells for oral delivery of macromolecular drugs and particles.26,52 For example, Ulex europaeus 1 (UEAl), a lectin specific for a-L-fucose residues, selectively binds to mouse Peyer s patch M cells.56 It has become apparent that UEAl can be used to target macromolecules to mouse Peyer s patch M cells and to enhance macromolecular... 

Clark, M. A., Jepson, M. A., Simmons, N. L, and Hirst, B. H. Selective binding and transcytosis of Ulex europaeus 1 lectin by mouse Peyer s patch M-cells in vivo. Cell Tissue Res. 282 455-461, 1995. 

Foster, N. Clark, M.A. Jepson, M.A. Hirst, B.H. Ulex europaeus 1 lectin targets microspheres to mouse peyer s patch M-Cells in vivo. Vaccine 1998, 16, 536-541. 

Ermak, T.H. et al. Uptake and transport of copolymer biodegradable microspheres by rabbit Peyer s patch M cells. Cell Tissue Res., 279, 2, 1995. 

Pappo, J., Ermak, T. H. and Steger, H. J., Monoclonal antibody-directed targeting of fluorescent polystyrene microspheres to Peyer s patch M cells. Immunology, 73, 277-280 (1991). 

Keynote review intestinal Peyer s patch M cells and oral vaccine targeting. Review Brayden et al. (2005)... 

Targeting of mucosal vaccines to Peyer s patch M cells. Review Frey and Neutra (1997)... 

Owen, R. L., and Bhalla, D. K., 1983, Cytochemical analysis of alkahne phosphatase and sterase activities and of lectin-binding and aitionic sites in rat and mouse Peyer s patch M cells,.4w. J. Anat. 168 199-212. 

LeFevre, M. E., Warren, J. B., and Joel, D. D., 1985b, Particles and macrophages in murine Peyer s patches, Exp. Cell Biol 53 121-129. 

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... 

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)... 

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... 

Salmonella all ages/travelers to tropics 6-48 h moderate volume, and usually without blood mucosal invasion via M cells or enterocytes - macrophages and lymphocytes in Peyer s patches and other lymphoid tissue - bloodstream... 

Jones, B. D., Ghori, N., and Falkow, S. (1994). Salmonella typhimurium initiates murine infection by penetrating and destroying the specialized epithelial M cells of the Peyer s patches. /. Exp. Med. 180,15-23. 

Specialised epithelial cells, M-ceUs, overlie Peyer s patches and isolated follicles, to facilitate the transport... 

Gut associated lymphoid tissues (GALT) contain the so-called Peyer s patches which are organized lymphoid follicles with overlying M cells and are considered to be the main entry point for particulate matter during passage down the GI tract (Figure 12.3 and Figure 12.4). 

Membranous epithelial M cells are a part of the organized mucosa-associated lymphoid tissue (O-MALT). These cells are specialized for antigen sampling. Also, they are exploited as a route of invasion by several pathogens.39 M cells are concentrated in follicle-associated epithelial (FAE) tissue called Peyer s patches in the small intestine. As M cells carry out endocytotic transport, they can be potential vehicles for mucosal drug and vaccine delivery. 

Figure 10.1 Pathways for intestinal absorption of macromolecular drugs, (a) Paracellular transport of macromolecules can be achieved by altering or disrupting the tight junctions that exist between cells and are only permeable to small molecules (<100 to 200 Da). (b) Adsorptive enterocytes and (c) M cells of Peyer s patches allow transcellular transport of macromolecules involving transcytosis and receptor-mediated endocytosis.

The Peyer s patches are found particularly in the distal ileum of the intestinal tract. The epithelium covering the Peyer s patches comprises specialized antigen-presenting epithelial cells, called M-cells (modified epithelial cells). This lymphoid tissue plays an important part in the body s immune system, as it samples antigenic material entering the GI tract and mounts an immune response as appropriate. The uptake and translocation of antigen by the M-cells of Peyer s patches can be exploited for oral drug and vaccine delivery, as described below (Section 6.7.7). 

Peyer s patches. Transcellular shuttling through the M cells to the underlying Peyer s patch may involve an adsorptive and/or receptor-mediated process, with membrane-bound vacuoles or vacuoles already present in the apical cytoplasm of the cells (see below, Section 6.7.7). 

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