摘要
目的 :探讨脂多糖结合蛋白 (LBP)对脂多糖 (LPS)激活肺泡巨噬细胞内p38信号通路的调节作用。方法 :经硫酸铵盐析、Bio -Rex70阳离子交换层析和MonoQ阴离子交换层析 ,从大鼠急性期血清中分离纯化LBP。分别用 0 0 1mg/L和 1mg/L的LPS刺激肺泡巨噬细胞 ,并加入不同浓度LBP( 0mg/L、0 0 1mg/L、0 1mg/L、1mg/L和 10mg/L) ,观察肺泡巨噬细胞中p38蛋白激酶的磷酸化程度。结果 :纯化的大鼠LBP在SDS -PAGE的 6 0kD处呈现单一条带 ,并可增强LPS与单核细胞的结合。当LPS浓度为 0 0 1mg/L时 ,1mg/L以下的LBP可明显增敏LPS对肺泡巨噬细胞内p38信号通路的激活 ,并且这种增敏作用随LBP浓度的增加而增强。但LBP为 10mg/L时 ,LBP对LPS的增敏作用反而有所减弱 ;当LPS为 1mg/L时 ,LBP对LPS激活肺泡巨噬细胞内p38信号通路无调节作用。结论 :LBP对低浓度LPS( 0 0 1mg/L)激活肺泡巨噬细胞内p38信号通路有明显的调节作用 ;而高浓度LPS( 1mg/L)不需LBP的增敏作用 。
AIM: To investigate the regulatory effects of lipopolysaccharide binding protein(LBP)on activation of p38 signaling pathway induced by lipopolysaccharide(LPS)in alveolar macrophages. METHODS: The LBP from actue phase rat serum was purified by ammonium sulphate precipitation, Bio-Rex70 resin and the MonoQ column. Rat alveolar macrophages were exposed to LPS (0 01 mg/L or 1 mg/L) the various concentrations of LBP(0 mg/L, 0 01 mg/L, 0 1 mg/L,1 mg/L and 10 mg/L) Western blotting were used to detect phospho-p38 in alveolar macrophages RESULTS: SDS-PAGE analysis indicated that the purified preparation of rat LBP showed homogeneity and the molecular weight was 60 kD.The binding of lipopolysaccharide to mononuclear cells were enhanced by purified rat LBP. Stimulation of rat alveolar macrophages with LPS at concentration of 0.01 mg/L was LBP dependent. LBP at concentrations up to 1 mg/L was able to increase the activation of p38. However , when LBP concentrations were further increased to 10 mg/L, the phosphorylation levers of p38 were lower as compared with that in the presence of 1 mg/L. Stimulation of rat alveolar macrophages with LPS at concentrations of 1 mg/L was LBP-independent. CONCLUSION: The activation of p38 induced by LPS at lower concentration(0.01 mg/L ) was LBP-dependent, meanwhile, LPS at higher concentration (1 mg/L ) was LBP-independent.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2003年第9期1202-1205,共4页
Chinese Journal of Pathophysiology
基金
国家自然科学基金重点资助项目 (No .39730 2 10 )
关键词
脂多糖类
脂多糖结合蛋白
p38
巨噬细胞
肺泡
Lipopolysaccharides
Lipopolysaccharide binding protein
p38
Macrophages,alveolar
