Stimulation of phagocytosis and phagosome-lysosome fusion by glycolipids from Grifola frondasa (Maitake).

本文试图阐明灰树花（Grifola frondosa，Maitake）糖脂的结构与人单核细胞（MN）和多形核白细胞（PMN）吞噬过程的关系。灰树花（Grifola frondosa（Maitake））的特征脂质成分为心磷脂（CL）、磷脂酰丝氨酸（PS）、磷脂酰胆碱（PC）、磷脂酰肌醇（PI）、磷脂酸（PA）、磷脂酰胆碱（PC）、磷脂酰乙醇胺（PE）和3种糖脂（MGL-1，2，3）。采用薄层层析、红外光谱、FAB质谱和核磁共振等方法对舞茸糖脂的结构进行了研究。使用用糖脂（MGL-1，2，3）包被的杀死的金黄色葡萄球菌细胞，检测糖脂对人PMN或MN的吞噬作用的影响。荧光显微镜下吖啶橙染色计数细菌，测定PMN吞噬体-溶酶体融合率。超氧阴离子的产生由细胞色素c的还原来确定。MGL-2的吞噬作用和吞噬体-溶酶体融合均呈剂量依赖性，而MGL-1和MGL-3则无此作用。MGL-2包被葡萄球菌的吞噬率是未包被葡萄球菌的2倍，吞噬率是未包被葡萄球菌的6倍。MGL-2对PMN释放超氧阴离子无影响。我比较了来自沙门氏菌的脂多糖（LPS）与来自舞茸的MGL-2的效果。糖脂（MGL-2）可逆转LPS对吞噬功能的抑制作用。

In this report, I attempted to elucidate the relationship between the structure of glycolipids from Grifola frondosa (Maitake) and the mechnism of phagocytic processes in human monocytes (MN) or polymorphonuclear leukocytes (PMN). The characteristic lipid components of Grifola frondosa (Maitake) were cardiolipin (CL), phosphatidylserine (PS) phosphatidylcholine (PC), phosphatidylinositol (PI), phosphatidic Acid (PA), phosphatidylcholine (PC), phosphatidyl-ethanolamine (PE), and three classes of glycolipids (MGL-1,2,3). The structures of glycolipids from Maitake were determined by thin layr chromatography (TLC), Infrared spectrometry, FAB mass spectrometry and NMR spectrometry. The effect of glycolipids on phagocytosis by human PMN or MN using killed Staphylococcus aureus cells coated with glycolipids (MGL-1,2,3) was examined. The rate of phagosome-lysosome fusion by PMN was determined by counting acridine orange-stained bacteria under a fluorescence microscope. Superoxide anion production was determined by the reduction of cytochrome c. Both phagocytosis and phagosome-lysosome fusion of MGL-2 was stimulated in dose-dependent manner, while MGL-1 and MGL-3 did not. Relative phagosome-lysosome fusion rate of MGL-2-coated staphylococci was six times higher than that of the noncoated control and phagocytic rate was twice, respectively. The superoxide anion release from PMN was not affected by MGL-2. I compared the effect of lipopolysaccharide (LPS) from Salmonella enteritidis with that of MGL-2 from Maitake. The glycolipid (MGL-2) reversed the inhibition of phagocytosis by LPS.