Surfactant protein A protects growing cells and reduces TNF-alpha activity from LPS-stimulated macrophages
Surfactant protein A protects growing cells and reduces TNF-alpha activity from LPS-stimulated macrophages
复制标题
DOI：
10.1152/ajplung.1996.271.2.l310
复制
发表时间：
1996-08-01
影响因子：
4.9
通讯作者：
Wright, JR
中科院分区：
文献类型：
--
作者：
McIntosh, JC;MervinBlake, S;Wright, JR
In addition to its effect on surfactant lipids, surfactant protein (SP)-A promotes host defense. To define further the role of SP-A in regulating immune cell function, we evaluated the effect of SP-A on lipopolysaccharide (LPS)-activated alveolar macrophages in two settings. First, cocultured LPS-activated macrophages significantly inhibited lung fibroblast growth, but SP-A (added daily) attenuated this effect. Both LPS and SP-A acted via macrophages rather than directly on the fibroblasts, at least partially by affecting tumor necrosis factor (TNF)-alpha activity. TNF-alpha reproduced the growth suppression, anti-TNF-alpha antibodies attenuated the effect of LPS-activated macrophages, and SP-A reduced TNF-alpha activity in conditioned medium. Second, SP-A reduced TNF-alpha activity in medium from isolated LPS-stimulated macrophages. The effects of SP-A were noted with or without serum, were dose-dependent and reversible, and were seen with two different serotypes of smooth LPS. Equimolar concentrations of immunoglobulin G and C1q had no effect. Thus SP-A both enhances host defense and modulates immune functions of alveolar macrophages.
