title: Intestinal villous M cells: an antigen entry site in the mucosal epithelium.
abstract: M cells located in the follicle-associated epithelium of Peyer's patches (PP) are shown to be the principal sites for the sampling of gut luminal antigens. Thus, PP have long been considered the gatekeepers of the mucosal immune system. Here, we report a distinct gateway for the uptake of gut bacteria: clusters of non-follicle-associated epithelium-associated Ulex europaeus agglutinin (UEA)-1(+) cells, which we have designated intestinal villous M cells. Interestingly, villous M cells are developed in various PP [or gut-associated lymphoid tissue (GALT)]-null mice, such as in utero lymphotoxin beta receptor (LTbetaR)-Ig-treated, lymphotoxin alpha (LTalpha)(-/-), tumor necrosis factor/LTalpha(-/-), and inhibition of differentiation 2 (Id2)(-/-) mice. Intestinal villous M cells have been observed to take up GFP-expressing Salmonella, Yersinia, and Escherichia coli-expressing invasin, as well as gut bacterial antigen for subsequent induction of antigen-specific immune responses. Thus, the identified villous M cells could be an alternative and PP-independent gateway for the induction of antigen-specific immune responses by means of the mucosal compartment.
authors.affiliation: Department of Mucosal Immunology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
authors.forename: Myoung Ho
authors.initials: MH
authors.lastname: Jang
authors.forename: Mi-Na
authors.initials: MN
authors.lastname: Kweon
authors.forename: Koichi
authors.initials: K
authors.lastname: Iwatani
authors.forename: Masafumi
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Terahara
authors.forename: Chihiro
authors.initials: C
authors.lastname: Sasakawa
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Suzuki
authors.forename: Tomonori
authors.initials: T
authors.lastname: Nochi
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Yokota
authors.forename: Paul D
authors.initials: PD
authors.lastname: Rennert
authors.forename: Takachika
authors.initials: T
authors.lastname: Hiroi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tamagawa
authors.forename: Hideki
authors.initials: H
authors.lastname: Iijima
authors.forename: Jun
authors.initials: J
authors.lastname: Kunisawa
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Yuki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kiyono
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology*; D001422:Bacterial Adhesion; D007413:Intestinal Mucosa / Q000166:cytology* / Q000276:immunology / Q000382:microbiology / Q000648:ultrastructure; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008854:Microscopy, Electron; D010581:Peyer's Patches / Q000276:immunology; D012486:Salmonella typhimurium / Q000502:physiology
chemical_list: D000941:Antigens