Expression and regulation of antimicrobial peptides in the gastrointestinal tract
Expression and regulation of antimicrobial peptides in the gastrointestinal tract
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DOI：
10.1189/jlb.0503249
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发表时间：
2004-01-01
影响因子：
5.5
通讯作者：
Mahida, YR
中科院分区：
文献类型：
--
作者：
Cunliffe, RN;Mahida, YR
胃肠道（GI）暴露于各种微生物。抗菌肽的表达已在胃肠道的不同区域得到证实，主要是在上皮细胞中，这些细胞代表了微生物必须与之相互作用以进行入侵的第一个宿主细胞。肠上皮单层是复杂的，由不同的细胞类型组成，并且大多数具有有限的寿命。在GI抗微生物肽中，α-和β-防御素已被研究得最多，并且由不同类型的上皮细胞表达。肠道α-防御素表达通常限于小肠中的潘氏细胞和中间细胞。然而，在肠α-防御素的前体形式的加工中，小鼠和人类之间存在重要差异。寄生虫感染诱导小鼠小肠中肠α-防御素表达的潘氏细胞和中间细胞的数量增加。在慢性炎症的结肠粘膜中，化生的潘氏细胞（在正常结肠中不存在）也表达肠α-防御素。β-防御素的上皮表达可以是组成型的或由感染和炎症刺激诱导的。β-防御素家族的一些成员的产生似乎仅限于胃肠道的不同部分。最近的研究使用基因操作的啮齿动物已经证明了肠道抗菌肽在先天宿主防御微生物中的可能体内重要性。这些肽作为先天性和适应性免疫系统细胞的化学引诱物的能力也可能在胃肠道慢性炎症的持续中发挥重要作用。
The gastrointestinal (GI) tract is exposed to a wide range of microorganisms. The expression of antimicrobial peptides has been demonstrated in different regions of the GI tract, predominantly in epithelial cells, which represent the first host cells with which the microorganisms have to interact for invasion. The intestinal epithelial monolayer is complex, consisting of different cell types, and most have a limited lifespan. Of the GI antimicrobial peptides, alpha- and beta-defensins have been studied the most and are expressed by distinct types of epithelial cells. Enteric alpha-defensin expression is normally restricted to Paneth and intermediate cells in the small intestine. However, there are important differences between mice and humans in the processing of the precursor forms of enteric alpha-defensins. Parasite infection induces an increase in the number of enteric alpha-defensin-expressing Paneth and intermediate cells in the murine small intestine. In the chronically inflamed colonic mucosa, metaplastic Paneth cells (which are absent in the normal colon) also expres's enteric alpha-defensins. Epithelial expression of beta-defensins may be constitutive or inducible by infectious and inflammatory stimuli. The production of some members of the beta-defensin family appears to be restricted to distinct parts of the GI tract. Recent studies using genetically manipulated rodents have demonstrated the likely in vivo importance of enteric antimicrobial peptides in innate host defense against microorganisms. The ability of these peptides to act as chemoattractants for cells of the innate- and adaptive-immune system may also play an important role in perpetuating chronic inflammation in the GI tract.