Pulmonary vascular inflammation: effect of TLR signalling on angiopoietin/TIE regulation
Pulmonary vascular inflammation: effect of TLR signalling on angiopoietin/TIE regulation
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DOI：
10.1111/1440-1681.12680
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发表时间：
2017-01-01
影响因子：
2.9
通讯作者：
Klaschik, Sven
中科院分区：
文献类型：
--
作者：
Hilbert, Tobias;Dornbusch, Kathrin;Klaschik, Sven
肺血管阻力增加是脓毒症的重要并发症。Toll样受体（TLR）和血管生成素（ANG）信号通路均参与肺动脉高压的发生。我们假设TLR刺激细菌配体直接影响血管生成素/TIE轴的配体和受体的表达和分泌。将肺源性微血管内皮细胞（HPMEC）和平滑肌细胞（SMC）与凝血酶以及TLR 2、-4、-5和-9的配体一起孵育。采用实时荧光定量PCR和ELISA法检测ANG 1、2、TIE 2和IL-8的表达和分泌。TLR刺激对HPMEC中ANG 2和TIE 2的表达以及SMC中ANG 1的表达均无影响。然而，在用TLR 9配体CpG刺激后，释放的ANG 1和-2的总体水平减半，并且当最初由顺序进行的刺激引起时，TLR 4活化显著增强ANG 2释放。此外，增强的ANG 2活性增加了内皮通透性，如体外transwell试验所示。我们的结论是，细菌配体的单一TLR刺激对人肺血管细胞中ANG 1，-2和TIE 2的表达和分泌的改变没有显著作用。需要各种刺激之间的相互作用来诱导ANG 1和-2之间的不平衡。
Increased pulmonary vascular resistance is a critical complication in sepsis. Toll-like receptor (TLR) as well as angiopoietin (ANG) signalling both contribute to the emergence of pulmonary arterial hypertension. We hypothesized that TLR stimulation by bacterial ligands directly affects expression and secretion of ligands and receptors of the angiopoietin/TIE axis. Microvascular endothelial (HPMEC) and smooth muscle cells (SMC) of pulmonary origin were incubated with thrombin and with ligands for TLR2, -4, -5, and -9. Expression and secretion of ANG1, -2, TIE2 and IL-8 were determined using quantitative real-time PCR and ELISA. TLR stimulation had no impact either on the expression of ANG2 and TIE2 in HPMEC or on that of ANG1 in SMC. However, overall levels of both released ANG1 and -2 were halved upon stimulation with the TLR9 ligand CpG, and ANG2 release was significantly enhanced by TLR4 activation when initially provoked by sequentially performed stimulation. Furthermore, enhanced ANG2 activity increased endothelial permeability, as demonstrated in an in vitro transwell assay. We conclude that sole TLR stimulation by bacterial ligands plays no significant role for altered expression and secretion of ANG1, -2 and TIE2 in human pulmonary vascular cells. The interplay between various stimuli is required to induce imbalances between ANG1 and -2.