Departamento de Patologia, Centro de Ciencias Biologicas, Universidade Estadual de Londrina, Rodovia Celso Garcia Cid PR445 KM380, 86051-990, Londrina, Parana, Brazil.
Can J Physiol Pharmacol. 2012 Feb;90(2):187-99. doi: 10.1139/y11-116. Epub 2012 Feb 9.
Endothelin mediates neutrophil recruitment during innate inflammation. Herein we address whether endothelin-1 (ET-1) is involved in neutrophil recruitment in adaptive inflammation in mice, and its mechanisms. Pharmacological treatments were used to determine the role of endothelin in neutrophil recruitment to the peritoneal cavity of mice challenged with antigen (ovalbumin) or ET-1. Levels of ET-1, tumour necrosis factor α (TNFα), and CXC chemokine ligand 1 (CXCL1) were determined by enzyme-linked immunosorbent assay. Neutrophil migration and flow cytometry analyses were performed 4 h after the intraperitoneal stimulus. ET-1 induced dose-dependent neutrophil recruitment to the peritoneal cavity. Treatment with the non-selective ET(A)/ET(B) receptor antagonist bosentan, and selective ET(A) or ET(B) receptor antagonists BQ-123 or BQ-788, respectively, inhibited ET-1- and ovalbumin-induced neutrophil migration to the peritoneal cavity. In agreement with the above, the antigen challenge significantly increased levels of ET-1 in peritoneal exudates. The ET-1- and ovalbumin-induced neutrophil recruitment were reduced in TNFR1 deficient mice, and by treatments targeting CXCL1 or CXC chemokine receptor 2 (CXCR2); further, treatment with bosentan, BQ-123, or BQ-788 inhibited ET-1- and antigen-induced production of TNFα and CXCL1. Furthermore, ET-1 and ovalbumin challenge induced an increase in the number of cells expressing the Gr1(+) markers in the granulocyte gate, CD11c(+) markers in the monocyte gate, and CD4(+) and CD45(+) (B220) markers in the lymphocyte gate in an ET(A)- and ET(B)-dependent manner, as determined by flow cytometry analysis, suggesting that ET-1 might be involved in the recruitment of neutrophils and other cells in adaptive inflammation. Therefore, the present study demonstrates that ET-1 is an important mediator for neutrophil recruitment in adaptive inflammation via TNFα and CXCL1/CXCR2-dependent mechanism.
内皮素在先天炎症中介导中性粒细胞募集。在此,我们研究内皮素-1(ET-1)是否参与了小鼠适应性炎症中的中性粒细胞募集及其机制。使用药理学治疗来确定内皮素在抗原(卵清蛋白)或 ET-1 刺激后小鼠腹腔内中性粒细胞募集中的作用。通过酶联免疫吸附试验测定 ET-1、肿瘤坏死因子α(TNFα)和 CXC 趋化因子配体 1(CXCL1)的水平。在腹腔内刺激后 4 小时进行中性粒细胞迁移和流式细胞术分析。ET-1 诱导剂量依赖性中性粒细胞向腹腔募集。用非选择性 ET(A)/ET(B)受体拮抗剂波生坦、选择性 ET(A)或 ET(B)受体拮抗剂 BQ-123 或 BQ-788 分别处理,可抑制 ET-1 和卵清蛋白诱导的中性粒细胞向腹腔迁移。与此一致的是,抗原挑战明显增加了腹腔渗出液中的 ET-1 水平。TNFR1 缺陷小鼠中 ET-1 和卵清蛋白诱导的中性粒细胞募集减少,靶向 CXCL1 或 CXC 趋化因子受体 2(CXCR2)的治疗也减少了这种募集;此外,波生坦、BQ-123 或 BQ-788 处理抑制了 ET-1 和抗原诱导的 TNFα 和 CXCL1 的产生。此外,通过流式细胞术分析,ET-1 和卵清蛋白刺激以 ET(A)和 ET(B)依赖性方式增加了粒细胞门中 Gr1(+)标记物表达的细胞数量、单核细胞门中 CD11c(+)标记物表达的细胞数量以及淋巴细胞门中 CD4(+)和 CD45(+)(B220)标记物表达的细胞数量,表明 ET-1 可能参与了适应性炎症中中性粒细胞和其他细胞的募集。因此,本研究表明,ET-1 通过 TNFα 和 CXCL1/CXCR2 依赖性机制成为适应性炎症中中性粒细胞募集的重要介质。