血清对分离枯否细胞细菌脂多糖摄取过程的影响

Effects of serum on the uptake of lipopolysaccharide by isolated rat Kupffer cells

本文应用单克隆抗细菌脂多糖抗体，利用免疫荧光及激光共聚焦扫描技术，观察了分离培养的枯否细胞在有无血清条件下对二种不同分子结构细菌脂多糖摄取过程的影响。无血清状态下，枯否细胞加入S型脂多糖（S—LPS）及R型脂多糖（Rd—LPS）培育5min后，其胞浆内抗脂多糖荧光强度显著高于空白对照水平，且S—LPS培育后胞浆内荧光强度增高幅度高于Rd—LPS培养后的增高幅度。10％小牛血清状态下，S—LPS培育5min后枯否细胞胞浆出现同等程度的抗脂多糖荧光强度增强，而Rd—LPS培育后枯否细胞胞浆荧光强度无明显改变。枯否细胞胞浆内抗脂多糖荧光着色呈小片状或同点状，胞核内未见明显着色。结果提示，分离培养的枯否细胞能迅速摄取脂多糖入胞浆，摄入胞浆中的脂多糖多以颗粒形式存在，且这一摄取过程受脂多糖分子结构及血液成分的影响。

By using a monoclonal antibody specific to the core lipid A region of lipopolysaccharides (LPS) and immunofluorescent technique, effects of serum on the uptake process of two types of LPS were observed with a confocal laser scanning microscope. It was found that the fluorescent intensity to LPS in the cytoplasm of isolated Kupffer cells increased significantly after 5min incubation with wild form LPS (S - LPS) or rough form LPS (Rd - LPS) in serum- free medium, and the increase of fluorescent intensity to LPS after incubation with S - LPS was much higher than that of Rd - LPS. When S -LPS and Rd - LPS were incubated in William's medium with 10% fetal bovine serum and then added to isolated Kupffer cells, similar increase of fluorescent intensity in the cytoplasm was found in cells incubated with S -LPS, but not much changes in cells incubated with Rd -LPS. Positive fluorescent reactions to both types of LPS were found scatteredly distributed in the cytoplasm of Kupffer cells in form of micellae, but not found in the nuclei. These results suggested that isolated Kupffer cells could quickly take up LPS into the cytoplasm, and this uptaking process may be affected by the chemical structure of LPS, as well as components in the blood.