Antibody anilino maytansinoid conjugates (AaMCs) have been prepared in which a maytansinoid bearing an aniline group was linked through the aniline amine to a dipeptide, which in turn was covalently attached to a desired monoclonal antibody. Several such conjugates were prepared utilizing different dipeptides in the linkage including Gly-Gly, l-Val-l-Cit, and all four stereoisomers of the Ala-Ala dipeptide. The properties of AaMCs could be altered by the choice of dipeptide in the linker. Each of the AaMCs, except the AaMC bearing a d-Ala-d-Ala peptide linker, displayed more bystander killing in vitro than maytansinoid ADCs that utilize disulfide linkers. In mouse models, the anti-CanAg AaMC bearing a d-Ala-l-Ala dipeptide in the linker was shown to be more efficacious against heterogeneous HT-29 xenografts than maytansinoid ADCs that utilize disulfide linkers, while both types of the conjugates displayed similar tolerabilities.
抗体氨基氮杂丝
氨霉素偶联物(AaMCs)已制备完成,其中一种含有
苯胺基团的氮杂丝
氨霉素通过
苯胺胺键与二肽连接,该二肽又通过共价键与所需单克隆
抗体相连。利用不同二肽(包括甘-甘、左旋缬-左旋瓜
氨酸和丙
氨酸-丙
氨酸的四种立体异构体)制备了多种此类偶联物。通过选择连接子中的二肽,可以改变AaMCs的性质。除携带d-Ala-d-Ala肽链连接子的AaMC外,每种AaMC在体外均显示出比使用二
硫键连接子的氮杂丝
氨霉素ADC更高的旁观者杀伤效果。在小鼠模型中,携带d-Ala-l-Ala二肽连接子的抗CanAg AaMC在对抗异质性HT-29异种移植方面比使用二
硫键连接子的氮杂丝
氨霉素ADC更有效,而这两种偶联物显示出相似的耐受性。