Tanabe S-I, Bodet C, Grenier D
Groupe de Recherche en Ecologie Buccale, Faculté de Médecine Dentaire, Université Laval, Quebec City, Quebec, Canada.
J Periodontal Res. 2009 Aug;44(4):503-10. doi: 10.1111/j.1600-0765.2008.01141.x. Epub 2008 Oct 22.
Treponema denticola is a key pathogen associated with periodontitis, a chronic inflammatory disease affecting tooth-supporting tissues. In the present study, we investigated the response of human macrophage-like cells to stimulation by peptidoglycan isolated from T. denticola. We also studied the effect of the peptidoglycan preparation on the phosphorylation state of kinases.
Monoblastic leukemia cells (U937 strain) were differentiated into adherent macrophage-like cells using phorbol myristic acid prior to being stimulated for 6 or 24 h with various amounts of T. denticola peptidoglycan. Secreted inflammatory mediators were quantified by enzyme-linked immunosorbent assays. The phosphorylation state of kinases was determined by immunoblotting.
The T. denticola peptidoglycan preparation, which was non-toxic for macrophage-like U937 leukemia cells at the concentration used, significantly increased, in a dose-dependent manner, the secretion of the pro-inflammatory cytokines tumor necrosis factor alpha, interleukin-1beta and interleukin-6. It also increased the secretion of two potent chemokines, interleukin-8 (IL-8) and regulated on activation normal T cell expressed and secreted (RANTES). T. denticola peptidoglycan also induced a significant increase in the secretion of prostaglandin E(2) and matrix metalloproteinase 9 by macrophage-like cells. The phosphorylation state of several kinases, including extracellular regulated protein-serine kinase 2 (+99%), G protein-coupled receptor-serine kinase 2 (+50%), Yes-related protein-tyrosine kinase (+44%) and extracellular regulated protein-serine kinase 1 (+30%) also increased following stimulation with the peptidoglycan preparation.
T. denticola peptidoglycan activates intracellular signaling pathways, leading to an increased production of inflammatory mediators by macrophage-like cells.
齿垢密螺旋体是一种与牙周炎相关的关键病原体，牙周炎是一种影响牙齿支持组织的慢性炎症性疾病。在本研究中，我们调查了人巨噬细胞样细胞对从齿垢密螺旋体分离的肽聚糖刺激的反应。我们还研究了肽聚糖制剂对激酶磷酸化状态的影响。
单核细胞白血病细胞（U937株）在用佛波醇肉豆蔻酸酯分化为贴壁巨噬细胞样细胞后，用不同量的齿垢密螺旋体肽聚糖刺激6或24小时。通过酶联免疫吸附测定法定量分泌的炎症介质。通过免疫印迹法测定激酶的磷酸化状态。
在所用浓度下对巨噬细胞样U937白血病细胞无毒的齿垢密螺旋体肽聚糖制剂，以剂量依赖性方式显著增加促炎细胞因子肿瘤坏死因子α、白细胞介素-1β和白细胞介素-6的分泌。它还增加了两种强效趋化因子白细胞介素-8（IL-8）和正常T细胞激活后表达和分泌的调节趋化因子（RANTES）的分泌。齿垢密螺旋体肽聚糖还诱导巨噬细胞样细胞分泌前列腺素E2和基质金属蛋白酶9显著增加。在用肽聚糖制剂刺激后，包括细胞外调节蛋白丝氨酸激酶2（+99%）、G蛋白偶联受体丝氨酸激酶2（+50%）、Yes相关蛋白酪氨酸激酶（+44%）和细胞外调节蛋白丝氨酸激酶1（+30%）在内的几种激酶的磷酸化状态也增加。
齿垢密螺旋体肽聚糖激活细胞内信号通路，导致巨噬细胞样细胞产生更多的炎症介质。
