Chemical and Chemoenzymatic Synthesis of S-Linked Ganglioside Analogues and Their Protein Conjugates for Use as Immunogens
作者:Jamie R. Rich、Warren W. Wakarchuk、David R. Bundle
DOI:10.1002/chem.200500518
日期:2006.1.11
Analogues of the tumor-associated gangliosides GM(3) and GM(2) containing terminal S-linked neuraminic acid residues and an amino terminated, truncated ceramide homologue have been synthesized and conjugated to a protein. The synthesis involved coupling of a S-linked sialyl alpha(2-->3) galactose disaccharide with a glucosyl sphingosine analogue, followed by elaboration and deprotection to give amino-terminated
合成了与肿瘤相关的神经节苷脂GM(3)和GM(2)的类似物,这些神经节苷脂含有末端S连接的神经氨酸残基和一个氨基末端,截短的神经酰胺同系物,并与蛋白质偶联。合成过程包括将S-连接的唾液酸α(2-> 3)半乳糖二糖与葡萄糖基鞘氨醇类似物偶联,然后进行精制和脱保护,得到氨基末端的糖基神经酰胺1。糖基转移酶催化的三糖1的延伸提供了可及性。修饰的GM(2)四糖2或含硫的GD(3)类似物30。由于它们对内源性糖苷水解酶的潜在抗性增强以及其固有的非自身特性,含有非还原性末端硫糖苷键的糖类抗原可能比O型连接的抗原更具免疫原性,并且可以刺激能够识别天然存在的寡糖的抗体的产生。我们的初步结果表明,实际上这些抗原是可行的免疫原,此外,在异源糖蛋白结合物的情况下,免疫血清与O-神经节苷脂发生交叉反应。