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B cell development in GALT: role of bacterial superantigen-like molecules.

ABSTRACT: Intestinal bacteria drive the formation of lymphoid tissues, and in rabbit, bacteria also promote development of the preimmune Ab repertoire and positive selection of B cells in GALT. Previous studies indicated that Bacillus subtilis promotes B cell follicle formation in GALT, and we investigated the mechanism by which B. subtilis stimulates B cells. We found that spores of B. subtilis and other Bacillus species, including Bacillus anthracis, bound rabbit IgM through an unconventional, superantigen-like binding site, and in vivo, surface molecules of B. anthracis spores promoted GALT development. Our study provides direct evidence that B cell development in GALT may be driven by superantigen-like molecules, and furthermore, that bacterial spores modulate host immunity.

SUBMITTER: Severson KM

PROVIDER: S-EPMC3419943 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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B cell development in GALT: role of bacterial superantigen-like molecules.

Severson Kari M KM Mallozzi Michael M Driks Adam A Knight Katherine L KL

Journal of immunology (Baltimore, Md. : 1950) 20100507 12

Intestinal bacteria drive the formation of lymphoid tissues, and in rabbit, bacteria also promote development of the preimmune Ab repertoire and positive selection of B cells in GALT. Previous studies indicated that Bacillus subtilis promotes B cell follicle formation in GALT, and we investigated the mechanism by which B. subtilis stimulates B cells. We found that spores of B. subtilis and other Bacillus species, including Bacillus anthracis, bound rabbit IgM through an unconventional, superanti ...[more]

PMID: 20483765

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