期刊
JOURNAL OF EXPERIMENTAL MEDICINE
卷 207, 期 1, 页码 29-37出版社
ROCKEFELLER UNIV PRESS
DOI: 10.1084/jem.20090633
关键词
-
资金
- Ministry of Education, Culture, Sports, Science, and Technology of Japan
- Core Research for Evolutional, Science, and Technology, Japan Science and Technology Agency
The complement system is an essential component of innate immunity, participating in the pathogenesis of inflammatory diseases and in host defense. In the lectin complement pathway, mannose-binding lectin (MBL) and ficolins act as recognition molecules, and MBL-associated serine protease (MASP) is a key enzyme; MASP-2 is responsible for the lectin pathway activation. The function of other serine proteases (MASP-1 and MASP-3) is still obscure. In this study, we generated a MASP-1- and MASP-3-deficient mouse model (Masp1/3(-/-)) and found that no activation of the alternative pathway was observed in Masp1/3(-/-) serum. Mass spectrometric analysis revealed that circulating complement factor D (Df) in Masp1/3(-/-) mice is a zymogen (pro-Df) with the activation peptide QPRGR at its N terminus. These results suggested that Masp1/3(-/-) mice failed to convert pro-Df to its active form, whereas it was generally accepted that the activation peptide of pro-Df is removed during its secretion and factor D constitutively exists in an active form in the circulation. Furthermore, recombinant MASP-1 converted pro-Df to the active form in vitro, although the activation mechanism of pro-Df by MASP-1 is still unclear. Thus, it is clear that MASP-1 is an essential protease of both the lectin and alternative complement pathways.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据