Plourde R, Phillips A T, Wu C H, Hays R M, Chowdhury J, Chowdhury N, Wu G Y
Immune Response Corporation, Carlsbad, California, USA.
Bioconjug Chem. 1996 Jan-Feb;7(1):131-7. doi: 10.1021/bc950083m.
A derivative of colchicine was synthesized, in a manner that preserved its important structural features, and conjugated to an asialoglycoprotein. The conjugate was characterized by ultraviolet-visible spectrophotometry and protein analysis. An average coupling ratio of 2 mol of colchicine per mole of asialoglycoprotein was achieved. The conjugate was stable to incubation in serum but was split into its separate components under chemically reducing conditions. Incubation with cells in culture revealed that the conjugate had antiproliferative activity similar to that of colchicine, but only in asialoglycoprotein receptor-containing cells. There was no effect at all on asialoglycoprotein receptor (-) cells. Furthermore, the antiproliferative effect of the conjugate on receptor (+) cells was blocked by addition of a large molar excess of free asialoglycoprotein. Immunofluorescence microscopy revealed disruption of microtubules in cell cultures that were pretreated with the conjugate. These results indicate that a colchicine conjugate that is taken up specifically into cells by asialoglycoprotein receptors and released intracellularly in a biologically active form can be prepared.
合成了一种秋水仙碱衍生物，其合成方式保留了其重要的结构特征，并将其与去唾液酸糖蛋白偶联。通过紫外可见分光光度法和蛋白质分析对该偶联物进行了表征。实现了每摩尔去唾液酸糖蛋白平均2摩尔秋水仙碱的偶联比。该偶联物在血清中孵育时稳定，但在化学还原条件下会分解为其单独的组分。与培养细胞一起孵育表明，该偶联物具有与秋水仙碱相似的抗增殖活性，但仅在含有去唾液酸糖蛋白受体的细胞中如此。对去唾液酸糖蛋白受体（-）细胞完全没有影响。此外，通过添加大量摩尔过量的游离去唾液酸糖蛋白，可阻断偶联物对受体（+）细胞的抗增殖作用。免疫荧光显微镜检查显示，用该偶联物预处理的细胞培养物中的微管受到破坏。这些结果表明，可以制备一种通过去唾液酸糖蛋白受体特异性摄取到细胞中并以生物活性形式在细胞内释放的秋水仙碱偶联物。
