DSM Nutritional Products Ltd., R & D Human Nutrition and Health, P.O. Box 2676, 4002 Basel, Switzerland.
University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
Nutrients. 2018 Feb 13;10(2):203. doi: 10.3390/nu10020203.
Toll-like receptors (TLRs) are powerful molecular regulators by which the immune system may "sense" the environment and protect the host from pathogens or endogenous threats. In mammalian cells, several TLRs were identified with a tissue and cell type-specific distribution. Understanding the functions of specific TLRs is crucial for the development and discovery of compounds useful to maintaining or re-establishing homeostasis in the gastrointestinal tract (GIT). Due to their relevance in regulating the inflammatory response in the GIT, we will focus here on TLR2, TLR4, and TLR5. In particular, we describe (a) the molecular pathways activated by the stimulation of these receptors with their known bacterial ligands; (b) the non-bacterial ligands known to interact directly with TLR2 and TLR4 and their soluble forms. The scope of this minireview is to highlight the importance of bacterial and non-bacterial compounds in affecting the gut immune functions via the activation of the TLRs.
Toll 样受体（TLRs）是强大的分子调节剂，免疫系统可以通过它们“感知”环境并保护宿主免受病原体或内源性威胁。在哺乳动物细胞中，已经鉴定出几种具有组织和细胞类型特异性分布的 TLR。了解特定 TLR 的功能对于开发和发现有助于维持或重建胃肠道（GIT）内稳态的化合物至关重要。由于它们在调节 GIT 中的炎症反应方面的相关性，我们将在这里重点介绍 TLR2、TLR4 和 TLR5。特别是，我们描述了 (a) 这些受体受到其已知细菌配体刺激后激活的分子途径；(b) 已知直接与 TLR2 和 TLR4 及其可溶性形式相互作用的非细菌配体。这篇迷你综述的目的是强调细菌和非细菌化合物通过激活 TLR 对肠道免疫功能的影响的重要性。
