Thakurdas Shakeel M, Melicoff Ernestina, Sansores-Garcia Leticia, Moreira Daniel C, Petrova Youlia, Stevens Richard L, Adachi Roberto
Department of Pulmonary Medicine, The University of Texas M. D. Anderson Cancer Center and Center for Lung Inflammation and Infection, Institute for Biosciences and Technology, Houston, Texas 77030, USA.
J Biol Chem. 2007 Jul 20;282(29):20809-15. doi: 10.1074/jbc.M611842200. Epub 2007 Apr 23.
Although it has been shown that mast cell-deficient mice have diminished innate immune responses against bacteria, the most important immunoprotective factors secreted from activated mast cells have not been identified. Mouse mast cell protease 6 is a tetramer-forming tryptase. This serine protease is abundant in the secretory granules and is exocytosed upon bacterial challenge. Here we have described the generation of a mast cell protease-6-null mouse. Our discovery that mice lacking this neutral protease cannot efficiently clear Klebsiella pneumoniae from their peritoneal cavities reveals an essential role for this serine protease, and presumably its human ortholog, in innate immunity.
尽管已有研究表明，肥大细胞缺陷小鼠对细菌的固有免疫反应有所减弱，但激活的肥大细胞分泌的最重要的免疫保护因子尚未得到鉴定。小鼠肥大细胞蛋白酶6是一种形成四聚体的类胰蛋白酶。这种丝氨酸蛋白酶在分泌颗粒中含量丰富，并在细菌攻击时被胞吐。在这里，我们描述了肥大细胞蛋白酶6基因敲除小鼠的产生。我们发现，缺乏这种中性蛋白酶的小鼠无法有效地从腹腔清除肺炎克雷伯菌，这揭示了这种丝氨酸蛋白酶及其可能的人类同源物在固有免疫中的重要作用。
