Sensor molecules in intestinal innate immunity against bacterial infections
Sensor molecules in intestinal innate immunity against bacterial infections
复制标题
DOI：
10.1097/01.mog.0000208458.38772.2a
复制
发表时间：
2006-03-01
影响因子：
2.5
通讯作者：
Eckmann, L
中科院分区：
文献类型：
--
作者：
Eckmann, L
综述目的Toll样受体（TLR）和含核苷酸结合寡聚化结构域（NOD）的蛋白是微生物标记分子的先天免疫传感器。本文综述了这些传感器在肠道生理学中的功能，最近的研究发现TLR是膜结合的，并为微生物衍生的分子调查细胞外空间，而NOD含有蛋白质的细胞质和检测细胞质中的微生物分子。大多数微生物传感器识别细菌细胞壁及其附属物的成分。例如，TLR4检测革兰氏阴性细菌细胞壁中的脂多糖。TLR5识别鞭毛蛋白，鞭毛蛋白是细菌鞭毛运动所需的组分。NOD1识别革兰氏阳性细菌细胞壁中含有二氨基庚二酸的二肽或三肽基序，而NOD2检测胞壁酰二肽，一种普遍存在的细胞壁肽聚糖基序。因此，TLR4是沙门氏菌根除所必需的，NOD1有助于控制幽门螺杆菌感染，NOD2参与粘膜防御单核细胞增生李斯特菌。这些传感器还调节粘膜炎症独立的病原体infections.Summary Toll样受体和核苷酸结合寡聚化结构域的蛋白质不仅在宿主防御已知的胃肠道细菌病原体中发挥关键作用，但也有助于粘膜稳态在明显缺乏这样的病原体。
Purpose of review Toll-like receptors (TLRs) and nucleotide-binding oligomerization domain (NOD)-containing proteins are innate immune sensors for microbial signature molecules. This review highlights new insights into the functions of these sensors in intestinal physiology.Recent findings TLRs are membrane bound and survey the extracellular space for microbe-derived molecules, while NOD-containing proteins are cytoplasmic and detect microbial molecules in the cytoplasm. Most microbial sensors recognize components of the bacterial cell wall and its appendages. For example, TLR4 detects lipopolysaccharide in the Gram-negative bacterial cell wall. TLR5 recognizes flagellin, a component of bacterial flagella required for motility. NOD1 recognizes diaminopimelic acid-containing dipeptide or tripeptide motifs in the Gram-positive bacterial cell wall, while NOD2 detects muramyl dipeptide, a ubiquitous cell wall peptidoglycan motif. These sensors are important for host defense against gastrointestinal pathogens, Thus, TLR4 is required for Salmonella eradication, NOD1 contributes to controlling Helicobacter pylori infection, and NOD2 is involved in mucosal defense against Listeria monocytogenes. These sensors also regulate mucosal inflammation independent of pathogen infections.Summary Toll-like receptors and nucleotide-binding oligomerization domain-containing proteins not only play critical roles in host defense against known gastrointestinal bacterial pathogens, but also contribute to mucosal homeostasis in the apparent absence of such pathogens.