Labeling of monoclonal antibodies with diethylenetriaminepentaacetic acid-appended radioiodinated peptides containing D-amino acids.
Labeling of monoclonal antibodies with diethylenetriaminepentaacetic acid-appended radioiodinated peptides containing D-amino acids.
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使用附加有二亚乙基三胺五乙酸的含有 D-氨基酸的放射性碘标记的肽标记单克隆抗体。
DOI：
10.1021/bc980075g
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Griffiths,GL
中科院分区：
文献类型：
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作者：
Govindan,SV;Mattes,MJ;Stein,R;McBride,BJ;Karacay,H;Goldenberg,DM;Hansen,HJ;Griffiths,GL
为了优化使用放射性碘内化单抗(MAbs)进行放射免疫治疗，必须开发实用的方法来提高131I在肿瘤中的滞留水平。以前设计的溶酶体包埋(“残存”)碘标记大多基于碳水化合物−酪胺加合物，但这些方法存在总产率低和/或mAb聚集水平高的缺点。我们开发了一种使用硫醇反应性的二乙三胺五乙酸−多肽加合物的方法，其中的多肽与包括d-酪氨酸在内的一个或多个氨基酸组装。通过在固相上制备官能团保护的多肽，用1-(p-异硫氰酸二苯甲基)R-Gly-d-Tyr-d-Lys[1-(p-thiocarbonylaminobenzyl)DTPA]，或DTPA二酸酐选择性地衍生化赖氨酸侧链，最后对多肽的N-末端进行衍生，使其含有马来酰亚胺基团。将这些多肽进行放射性碘标记，然后结合成二硫化物还原的单抗，以一瓶法进行，总产率为32−89%，比活度为1.8mCi/mg，聚集度小于2%。用该方法标记的两株内在型mAbL12(抗CD22B细胞淋巴瘤mAb)和Rs7(靶向EGP-1抗原的抗腺癌mAb)在体外对RAMOS和CALU-3肿瘤细胞的存留率分别是用氯胺-T法标记的单抗的2−3倍。给出了新方法的基本原理、合成、放射化学和体外数据。
The optimal use of radioiodinated internalizing monoclonal antibodies (mAbs) for radioimmunotherapy necessitates the development of practical methods for increasing the level of retention of131I in the tumor. Lysosomally trapped (“residualizing”) iodine radiolabels that have been previously designed are based mostly on carbohydrate−tyramine adducts, but these methods have drawbacks of low overall yields and/or high levels of mAb aggregation. We have developed a method using thiol-reactive diethylenetriaminepentaacetic acid (DTPA)−peptide adducts wherein the peptides are assembled with one or mored-amino acids, includingd-tyrosine. Two such substrates, R-Gly-d-Tyr-d-Lys[1-(p-thiocarbonylaminobenzyl)DTPA], referred to as IMP-R1, and [R-d-Ala-d-Tyr-d-Tyr-d-Lys]2(CA-DTPA), referred to as IMP-R2, wherein R is 4-(N-maleimidomethyl)cyclohexane-1-carbonyl, were synthesized by preparing functional group-protected peptides on a solid phase, selectively derivatizing the lysine side chain with 1-(p-isothiocyanatobenzyl)DTPA or DTPA dianhydride (CA-DTPA), deprotecting other functional groups, and finally derivatizing the peptide's N-terminus so it contained a maleimide group. Radioiodinations of the peptides followed by conjugations to disulfide-reduced mAbs, carried out as a one-vial procedure, resulted in 32−89% overall yields, at specific activities of 1.8−11.1 mCi/mg, with less than 2% aggregation. Two internalizing mAbs, LL2 (anti-CD 22 B-cell lymphoma mAb) and RS7 (an anti-adenocarcinoma mAb which targets EGP-1 antigen), labeled with this procedure exhibited a 2−3-fold better cellular retention in Ramos and Calu-3 tumor cell lines, in vitro, respectively, compared to the same mAbs radioiodinated with the chloramine-T method. The rationale for the new approach, syntheses, radiochemistry and in vitro data are presented.