Goitsuka Ryo, Chen Chen-Lo H, Benyon Lesley, Asano Yusuke, Kitamura Daisuke, Cooper Max D
Research Institute for Biological Sciences, Tokyo University of Science, Noda, Chiba 278-0022, Japan.
Proc Natl Acad Sci U S A. 2007 Sep 18;104(38):15063-8. doi: 10.1073/pnas.0707037104. Epub 2007 Sep 7.
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.
黏膜上皮M细胞为微生物提供了一个有效的进入途径。M细胞最初是在禽类法氏囊的不规则微绒毛和丰富的转胞吞通道中被定义的，在哺乳动物阑尾、派尔集合淋巴结和其他黏膜表面淋巴界面的淋巴滤泡相关上皮中也有发现。我们在此描述了鸡体内一个先前未被识别的cathelicidin基因chCATH - B1，它仅在法氏囊上皮中表达。与先前鉴定的cathelicidins的成熟肽一样，chCATH - B1的羧基末端肽对革兰氏阳性菌和革兰氏阴性菌具有广泛的抗菌活性。chCATH - B1的表达局限于M细胞的分泌上皮细胞邻域，而其成熟肽则被转运并集中在覆盖法氏囊淋巴滤泡的M细胞基底外侧表面周围的纤维网络上。我们得出结论，chCATH - B1在M细胞通道处处于有利位置，可发挥保护性抗菌作用。
