Toll-like receptors 2 and 4 are up-regulated during intestinal inflammation
Toll-like receptors 2 and 4 are up-regulated during intestinal inflammation
复制标题
DOI：
10.1053/gast.2002.33662
复制
发表时间：
2002-06-01
期刊：
影响因子：
29.4
通讯作者：
Rogler, G
中科院分区：
文献类型：
--
作者：
Hausmann, M;Kiessling, S;Rogler, G
背景与目的：细菌壁产物在肠粘膜免疫和非免疫细胞的激活中发挥重要作用。 Toll 样受体 (TLR) TLR2 和 TLR4 已被确定为由细菌壁成分激活的信号受体。方法：采用免疫组织化学方法分析内镜和手术获得的人肠粘膜中TLRs的表达。通过配备 CD33 抗体的免疫磁珠分离肠道巨噬细胞。对TLR1-5进行逆转录聚合酶链反应。结果通过 Northern blot 和流式细胞术得到证实。通过聚合酶链反应-酶联免疫吸附测定试剂盒对 Interleukin-1beta 信使 RNA (mRNA) 进行定量。结果：免疫组织化学显示，与非炎症粘膜相比，炎症肠粘膜粘膜下细胞的 TLR2 和 TLR4 抗原表达显着增加。通过双标记技术将 TLR 表达定位于肠道巨噬细胞。正常粘膜CD33阳性巨噬细胞的mRNA无法获得TLR-聚合酶链式反应产物。我们观察到炎症相关巨噬细胞中 TLR2、TLR4 和 TLR5 mRNA 的诱导。 TLR1 和 TLR3 仅在血液单核细胞中检测到。单核细胞对脂多糖刺激产生 3 倍的反应，体外分化的巨噬细胞细胞内白细胞介素 1β mRNA 增加 16 倍。来自正常粘膜的巨噬细胞对脂多糖没有反应，显示出 TLR 表达的功能相关性。结论：本研究显示肠道巨噬细胞中 TLR2 和 TLR4 表达的炎症依赖性诱导。 TLR 的缺失消除了粘膜巨噬细胞对细菌壁产物的反应性。因此，TLR 的存在可能会促进炎症过程。
Background & Aims: Bacterial wall products play an important role in the activation of immune and nonimmune cells of the intestinal mucosa. Toll-like receptors (TLRs) TLR2 and TLR4 have been identified as signaling receptors activated by bacterial wall components. Methods: Expression of TLRs in human intestinal mucosa obtained by endoscopy and surgery was analyzed by immunohistochemistry. Intestinal macrophages were isolated by immunomagnetic beads armed with a CD33 antibody. Reverse-transcription polymerase chain reaction was performed for TLR1-5. Results were confirmed by Northern blot and flow cytometry. Interleukin-1beta messenger RNA (mRNA) was quantified by a polymerase chain reaction-enzyme-linked immunosorbent assay-kit. Results: Immunohistochemistry revealed a significant increase in the TLR2 and TLR4 antigen expression on submucosal cells in inflamed intestinal mucosa compared with non-inflamed mucosa. TLR expression was localized in intestinal macrophages by double-labeling techniques. No TLR-polymerase chain reaction product could be obtained with mRNA from CD33-positive macrophages from normal mucosa. We observed an induction of mRNA for TLR2, TLR4, and TLR5 in inflammation-associated macrophages. TLR1 and TLR3 were only detectable in blood monocytes. Monocytes reacted to lipopolysaccharide stimulation with a 3-fold and in vitro differentiated macrophages with a 16-fold increase of cellular interleukin-1beta mRNA. Macrophages from normal mucosa did not respond to lipopolysaccharide showing the functional relevance of TLR expression. Conclusions: This study shows the inflammation-dependent induction of TLR2 and TLR4 expression in intestinal macrophages. The absence of TLRs abolishes the reactivity of mucosal macrophages to bacterial wall products. Presence of TLRs may thereby contribute to the inflammatory process.