大鼠胰腺神经节苷脂表达：自身免疫性胰岛B细胞破坏模型与正常品系之间的差异。

Rat pancreatic ganglioside expression: differences between a model of autoimmune islet B cell destruction and a normal strain.

作者信息

Dotta F, Tiberti C, Previti M, Anastasi E, Andreani D, Lenti L, Pontieri G M, Gianani R, Appel M C, Eisenbarth G S

机构信息

Clinica Medica 2 (Endocrinology), University of Rome, La Sapienza, Italy.

出版信息

Clin Immunol Immunopathol. 1993 Feb;66(2):143-9. doi: 10.1006/clin.1993.1018.

DOI:10.1006/clin.1993.1018

PMID:8453786

Abstract

Islet cell antibodies (ICA) bind antigens expressed in both human and rat pancreatic islets. Biochemical studies have shown that an ICA-autoantigen has the properties of a monosialo-ganglioside migrating between GM2 and GM1 standards (GM2-1). We therefore aimed to isolate and characterize gangliosides from whole pancreas and isolated islets of bio breeding diabetes-prone (BB-DP), bio breeding diabetes-resistant (BB-DR), and Wistar Furth (WF) rat strains. Gangliosides were characterized by TLC, HPLC, diode array analysis, and ganglioside-specific staining. ICA binding was studied by indirect immunostaining. The GM2-1 fraction was present in BB-DP, BB-DR, and WF rat pancreases (11, 17, and 9.5%, respectively, of total ganglioside content). Substantial differences were found in other fractions: in BB-DP pancreas, in addition to GM2-1, the main fractions were GM3 (49%), GD1a (12%), GT1b (5%), and a ganglioside migrating between GM1 and GD3 standards (23%), while in BB-DR pancreas the above components were 71, 5.5, 2, and 4.5%, respectively; in WF pancreas, the main fractions were GM3, GD3, GD1a, GT1b and a trisialoganglioside (GT*) migrating above the GT1b standard (42.7, 7, 20.2, 13.8, and 6.8, respectively). A different pattern of ganglioside expression was found in isolated islets of BB-DP, BB-DR, and WF rats: the GM2-1 fraction represented, respectively, 29.1, 30.4, and 31.6% of total ganglioside content; GM3 51.1, 66, and 68.4%. A fraction migrating between GM1 and GD3 standards was present only in BB-DP and BB-DR islets (19.8 and 3.6%, respectively). ICA-positive human sera reacted with pancreas of all rat strains studied, with similar end-point titers. In conclusion, (1) the GM2-1 ganglioside, in the same way as a putative target antigen of ICA, is equally expressed in BB-DP, BB-DR, and WF rat pancreata; and (2) the GM1-GD3 is expressed in higher amounts in BB-DP than in BB-DR pancreas and islets and is absent in WF.

摘要

胰岛细胞抗体（ICA）可与人及大鼠胰腺胰岛中表达的抗原结合。生化研究表明，一种ICA自身抗原具有在GM2和GM1标准物之间迁移的单唾液酸神经节苷脂（GM2-1）的特性。因此，我们旨在从生物繁殖糖尿病易感性（BB-DP）、生物繁殖糖尿病抗性（BB-DR）和Wistar Furth（WF）大鼠品系的全胰腺和分离的胰岛中分离并鉴定神经节苷脂。通过薄层层析（TLC）、高效液相色谱（HPLC）、二极管阵列分析和神经节苷脂特异性染色对神经节苷脂进行鉴定。通过间接免疫染色研究ICA结合情况。GM2-1组分存在于BB-DP、BB-DR和WF大鼠的胰腺中（分别占总神经节苷脂含量的11%、17%和9.5%）。在其他组分中发现了显著差异：在BB-DP胰腺中，除GM2-1外，主要组分是GM3（49%）、GD1a（12%）、GT1b（5%）以及一种在GM1和GD3标准物之间迁移的神经节苷脂（23%），而在BB-DR胰腺中，上述组分分别为71%、5.5%、2%和4.5%；在WF胰腺中，主要组分是GM3、GD3、GD1a、GT1b和一种迁移在GT1b标准物之上的三唾液酸神经节苷脂（GT*）（分别为42.7%、7%、20.2%、13.8%和6.8%）。在BB-DP、BB-DR和WF大鼠分离的胰岛中发现了不同的神经节苷脂表达模式：GM2-1组分分别占总神经节苷脂含量的29.1%、30.4%和31.6%；GM3分别为51.1%、66%和68.4%。一种在GM1和GD3标准物之间迁移的组分仅存在于BB-DP和BB-DR胰岛中（分别为19.8%和3.6%）。ICA阳性的人血清与所有研究的大鼠品系的胰腺反应，终点滴度相似。总之，（1）GM2-1神经节苷脂，与ICA的假定靶抗原一样，在BB-DP、BB-DR和WF大鼠胰腺中表达相同；（2）GM1-GD3在BB-DP中的表达量高于BB-DR的胰腺和胰岛，且在WF中不存在。