Development of intestinal M cells.
Intestinal epithelium contains several specialized cell types including M cells, which can be found in the follicle-associated epithelium (FAE) or occasionally on the villi. M cells are critical for sampling of intestinal flora and for transferring pathogens across the epithelial barrier for recognition by the immune system. Development of M cells on the villi (M(v)) is independent of the presence of lymphocytes, while development of the FAE and M cells within the FAE (M(f)) is dependent on B lymphocytes. Here, the concept is discussed that B cells are not required for induction of M(f) differentiation but are required for transition to and maintenance of the mature M(f) phenotype. Signaling pathways possibly involved in the B-cell-independent stages of M-cell development are also discussed.
Mach
Julie
J
The Jackson Laboratory, Bar Harbor, ME 04609, USA.
Hshieh
Tammy
T
Hsieh
Dennis
D
Grubbs
Nathaniel
N
Chervonsky
Alexander
A
D000818:Animals; D002454:Cell Differentiation / Q000276:immunology*; D006801:Humans; D018928:Immunity, Mucosal; D007413:Intestinal Mucosa / Q000166:cytology* / Q000276:immunology*