Kinoshita Makoto, Okada Masaharu, Hara Masatake, Furukawa Yutaka, Matsumori Akira
Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, 54 Kawaharacho Shogoin, Kyoto, 606-8397, Japan.
Arterioscler Thromb Vasc Biol. 2005 Sep;25(9):1858-63. doi: 10.1161/01.ATV.0000174797.71708.97. Epub 2005 Jun 23.
Recent studies have highlighted the pathogenetic importance of chronic inflammation in cardiovascular disorders such as congestive heart failure and atherosclerosis. Mast cells release a wide variety of immune mediators that may initiate inflammatory responses, whereas endothelial cells (ECs) play a prominent role in the pathogenesis of cardiovascular diseases by secreting cytokines. The purpose of this study was to clarify the role of mast cells as an activator of ECs.
ECs harvested from human umbilical cord veins were stimulated with mast cell granules (MCGs) prepared from sonicated human leukemic mast cells. The supernatants and total RNA from cells were collected. Levels of interleukin (IL)-1beta, tumor necrosis factor-alpha, and granulocyte colony-stimulating factor remained unchanged up to 24 hours. In contrast, levels of monocyte chemoattractant protein-1 (MCP-1) and IL-8 increased significantly within 6 hours. Northern blot analysis revealed an increase in MCP-1 and IL-8 mRNA expression in MCG-treated ECs. Induction of these chemokines was attenuated by antitryptase neutralizing antibody. Furthermore, MCP-1 and IL-8 were induced in ECs by incubation with human mast cell tryptase, but not with chymase.
These results indicate that the production of MCP-1 and IL-8 in ECs was induced by MCG and amplified by tryptase.
近期研究强调了慢性炎症在诸如充血性心力衰竭和动脉粥样硬化等心血管疾病发病机制中的重要性。肥大细胞释放多种可能引发炎症反应的免疫介质，而内皮细胞（ECs）通过分泌细胞因子在心血管疾病的发病机制中起重要作用。本研究的目的是阐明肥大细胞作为内皮细胞激活剂的作用。
用人白血病肥大细胞经超声处理制备的肥大细胞颗粒（MCGs）刺激从人脐静脉采集的内皮细胞。收集细胞的上清液和总RNA。白细胞介素（IL）-1β、肿瘤坏死因子-α和粒细胞集落刺激因子水平在24小时内保持不变。相比之下，单核细胞趋化蛋白-1（MCP-1）和IL-8水平在6小时内显著升高。Northern印迹分析显示，经MCG处理的内皮细胞中MCP-1和IL-8 mRNA表达增加。这些趋化因子的诱导被抗胰蛋白酶中和抗体减弱。此外，用人肥大细胞胰蛋白酶而非糜蛋白酶孵育内皮细胞可诱导MCP-1和IL-8。
这些结果表明，MCG诱导内皮细胞产生MCP-1和IL-8，并由胰蛋白酶放大。
