Abstract：Objective： To investigate the effect of lipopolysaccharides(LPS) on neutrophil phagocytosis and its potential mechanism. Methods：(1) Neutrophils separated from the blood samples of healthy adult were divided into control group, LPS 10 min, 20 min, 30 min group; each group was treated with GFPE.coli (25922GFP) in proportion as 1 ∶50 for 30 min. Neutrophil phagocytosis was detected by using flow cytometry and fluorescence microscope. (2) Neutrophils were randomly divided into control group, LPS group, LY294002(PI3K inhibitor) group and LPS+LY294002 group; some of them were stained with filamentous actin(F-actin) fluorochrome and analyzed by flow cytometry and fluorescence microscope. In addition, the neutrophil morphology and Factin were also observed by fluorescence microscope. Each group was treated with GFP-E.coli (25922GFP) in proportion as 1 ∶50 for 30 min. Neutrophil phagocytosis was detected by flow cytometry and fluorescence microscope. Expression of Akt, PI3K,p-Akt and pPI3K were determined by western blotting. Results： (1) Compared with control group, three LPS-treated groups showed higher expression levels of 25922GFP fluorescence and p-PI3K, pAkt in neutrophils; the neutrophil phagocytosis in three LPS-treated groups were higher than that in control group(both P＜0.05); (2) Compared with control group, LPS group had higher levels of F-actin expression, changed cell morphology, while there were no special changes of cell morphology in LY294002 group and LPS+LY294002 group; LPS+LY294002 group showed lower levels of F-actin than that in LPS group(P＜0.05). And there were no significant changes in expression of p-Akt among control goup, LY294002 group and LPS+LY294002 group, while lower than LPS group. Conclusion：LPS could enhance the neutrophil phagocytosis, which was associated with the activated phosphorylation of PI3K/Akt.
收稿日期: 2016-08-15
基金资助:
国家自然科学基金资助项目(81071546，81272148，81471903)
通讯作者:
孙炳伟(通讯作者)，教授，E-mail：sunbinwe@hotmail.com
作者简介: 张艺森(1992—)，男，硕士研究生；
引用本文:
张艺森，王旭，秦魏婷，宋明明，孙炳伟. 脂多糖调控PI3K/Akt通路增强中性粒细胞吞噬功能[J]. 江苏大学学报:医学版, 2016, 26(05): 395-399,404.
ZHANG Yi-sen, WANG Xu， QIN Wei-ting， SONG Ming-ming, SUN Bing-wei. Lipopolysaccharides enhances neutrophil phagocytosis of E.coli via PI3K/Akt pathway. Journal of Jiangsu University(Medicine Edition), 2016, 26(05): 395-399,404.
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2016, Vol. 26 
