Chicken cathelicidin-B1, an antimicrobial guardian at the mucosal M cell gateway.
Mucosal epithelial M cells provide an efficient portal of entry for microorganisms. Initially defined by their irregular microvilli and abundant transcytotic channels in the avian bursa of Fabricius, M cells also are found in the lymphoid follicle-associated epithelium of the mammalian appendix, Peyer's patches, and other mucosal surface-lymphoid interfaces. We describe here a previously unrecognized cathelicidin gene in chickens, chCATH-B1, that is expressed exclusively in the epithelium of the bursa of Fabricius. Like the mature peptides of previously identified cathelicidins, the carboxyl-terminal peptide of chCATH-B1 has broad antimicrobial activity against Gram-positive and Gram-negative bacteria. chCATH-B1 expression is restricted to the secretory epithelial cell neighbors of the M cells, whereas its mature peptide is transported to become concentrated on the fibrillar network surrounding basolateral surfaces of the M cells that overlie the bursal lymphoid follicles. We conclude that chCATH-B1 is well placed to serve a protective antimicrobial role at the M cell gateway.
Goitsuka
Ryo
R
Research Institute for Biological Sciences, Tokyo University of Science, Noda, Chiba 278-0022, Japan.
Chen
Chen-Lo H
CL
Benyon
Lesley
L
Asano
Yusuke
Y
Kitamura
Daisuke
D
Cooper
Max D
MD
D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000494:pharmacology / Q000502:physiology*; D030161:Avian Proteins / Q000235:genetics* / Q000494:pharmacology / Q000502:physiology*; D001483:Base Sequence; D002060:Bursa of Fabricius / Q000166:cytology / Q000276:immunology*; D002645:Chickens / Q000276:immunology*; D018076:DNA, Complementary / Q000378:metabolism; D004847:Epithelial Cells / Q000276:immunology; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D018928:Immunity, Mucosal; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D010802:Phylogeny; D054804:Cathelicidins