ヒトグリオーマ細胞におけるガングリオシド代謝速度の細胞密度依存性の検討

概要

論文の詳細を見る
The effects of cell density on the gangliosides of 5 human glioma cell lines were studied. The cell lines used were KG-1C (GM3-dominant), A172 and H4 (GM2-dominant), and Hs683 and SW1088 (GM3, GM2-co-dominant) cells. All these cell lines showed higher immunofluorescence with anti-ganglioside antibodies in FACS analysis at sparse density than at confluent density. The chemical content of gangliosides was consistent in spite of differences in cell densities. The mechanisms of crypticity of gangliosides at confluent culture were under investigation. We first evaluated the metabolic turnover rate of gangliosides at different cell densities. The results clearly showed a more rapid turnover of gangliosides at sparse density from approximately 2 to 15 fold in terms of radioactivities of incorporated tritium into gangliosides. Surface labeling of GM2 with the use of limited sodium periodate oxidation of sialylated residue equally labeled GM2 either from the confluent cells or the sparse cells. Disassembly of actin filaments with cytochalasin B(10μM) partially exposed cryptic GM2 of confluent cells, indicating reversibility of the crypticity. When the cells were observed with a confocal laser microscope, the distribution of gangliosides corresponded to adhesion plaque. Furthermore the result of immuno-electronmicroscopy showed that gangliosides were included in caveolae-like structures. We speculate that better accessibility of antibodies toward gangliosides should be facilitated by the same mechanism which should, in turn, provide easier access of carbohydrate-hydrolysis enzymes to gangliosides at sparse cell density in order to maintain an enhanced turnover rate. It is also possible that the function of gangliosides has something to do with cell-to-cell contact, proliferation, locomotion, and signal transduction.
札幌医科大学の論文
1997-12-01

ヒトグリオーマ細胞におけるガングリオシド代謝速度の細胞密度依存性の検討

スポンサーリンク

概要

著者

関連論文

スポンサーリンク