Dotta F, Colman P G, Lombardi D, Scharp D W, Andreani D, Pontieri G M, Di Mario U, Lenti L, Eisenbarth G S, Nayak R C
Joslin Diabetes Center, Boston, MA 02215.
Diabetes. 1989 Nov;38(11):1478-83. doi: 10.2337/diab.38.11.1478.
Recent biochemical studies have shown that the cytoplasmic islet cell-antibody autoantigen has properties of a monosialoganglioside (GM). To characterize islet glycolipids and ascertain whether islets express unique gangliosides, we determined the pattern of ganglioside expression in whole human pancreas and isolated human islets using high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC). The major gangliosides detected in glycolipid extracts of whole human pancreas were GM3, GD3 (disialoganglioside), and in a lesser amount, a GD1a-comigrating ganglioside. In contrast to whole human pancreas, isolated human islets were found to predominantly express GM3, an acidic glycolipid comigrating with GM2, and a ganglioside with mobility between GM2 and GM1 by both HPLC and HPTLC. Quantitation of the major ganglioside UV peaks seen on HPLC gave the following results. In whole pancreas, GM3 represented 66.7% of total gangliosides detected; an asialoglycolipid comigrating with GM2, 2.0%; a ganglioside migrating between GM2 and GM1, 2.6%; GD3, 22.6%; and a GD1a-comigrating ganglioside, 6.1%. In isolated islets, these components were found at the following levels: GM3, 14.9%; GM2-comigrating glycolipid, 74.2%; a ganglioside migrating between GM2 and GM1, 9.8%; GD3, 1.1%; and the GD1a-comigrating ganglioside, not detectable.
近期的生化研究表明，细胞质胰岛细胞抗体自身抗原具有单唾液酸神经节苷脂（GM）的特性。为了表征胰岛糖脂并确定胰岛是否表达独特的神经节苷脂，我们使用高效液相色谱（HPLC）和高效薄层色谱（HPTLC）测定了全人类胰腺和分离出的人类胰岛中神经节苷脂的表达模式。在全人类胰腺的糖脂提取物中检测到的主要神经节苷脂是GM3、GD3（双唾液酸神经节苷脂），以及少量与GD1a共迁移的神经节苷脂。与全人类胰腺不同，通过HPLC和HPTLC发现，分离出的人类胰岛主要表达GM3、一种与GM2共迁移的酸性糖脂，以及一种迁移率介于GM2和GM1之间的神经节苷脂。对HPLC上可见的主要神经节苷脂紫外峰进行定量分析，得到以下结果。在全胰腺中，GM3占检测到的总神经节苷脂的66.7%；与GM2共迁移的去唾液酸糖脂占2.0%；迁移率介于GM2和GM1之间的神经节苷脂占2.6%；GD3占22.6%；与GD1a共迁移的神经节苷脂占6.1%。在分离出的胰岛中，这些成分的含量如下：GM3占14.9%；与GM2共迁移的糖脂占74.2%；迁移率介于GM2和GM1之间的神经节苷脂占9.8%；GD3占1.1%；与GD1a共迁移的神经节苷脂未检测到。
