The (6-maleimidocaproyl)hydrazone of doxorubicin was synthesized and conjugated to several mAbs, including chimeric BR96, via a Michael addition reaction to thiol-containing mAbs. DTT reduction of disulfides present in the mAb was a reliable and general method for generating a consistent number of reactive SH groups. The conjugates, after purification by Bio-Beads, were free of unreacted linker and/or doxorubicin. All conjugates released doxorubicin under acidic conditions that mimic the lysosomal environment, while they were relatively stable at neutral pH. BR96 conjugates showed antigen-specific cytotoxicity.

中文翻译：

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阿霉素的（6-Maleimidocaproyl）--一种制备阿霉素免疫缀合物的新衍生物。

合成了阿霉素的（6-马来酰亚胺基己酰基）hydr，并通过与含硫醇的mAb进行迈克尔加成反应将其与几种mAb（包括嵌合BR96）偶联。DTT还原mAb中存在的二硫键是一种可靠且通用的方法，用于生成一致数量的反应性SH基团。在通过Bio-Beads纯化后，偶联物不含未反应的接头和/或阿霉素。所有缀合物在模拟溶酶体环境的酸性条件下释放阿霉素，而它们在中性pH下相对稳定。BR96偶联物显示出抗原特异性细胞毒性。