Engineering an antibody with picomolar affinity to DOTA chelates of multiple radionuclides for pretargeted radioimmunotherapy and imaging.
Engineering an antibody with picomolar affinity to DOTA chelates of multiple radionuclides for pretargeted radioimmunotherapy and imaging.
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DOI：
10.1016/j.nucmedbio.2010.08.013
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发表时间：
2011-02
影响因子：
3.1
通讯作者：
Wittrup KD
中科院分区：
文献类型：
--
作者：
Orcutt KD;Slusarczyk AL;Cieslewicz M;Ruiz-Yi B;Bhushan KR;Frangioni JV;Wittrup KD
在前靶向放射免疫治疗(PRIT)中，给予一种双功能抗体并允许其预先定位于肿瘤细胞。随后，细胞结合的抗体给药并捕获螯合的放射性核素，而未结合的半抗原则迅速从体内清除。我们的目标是将高亲和力的粘合剂设计成DOTA螯合物，用于PRIT应用。我们对抗体和半抗原药代动力学进行了数学建模，以分析半抗原肿瘤保留与半抗原结合亲和力的关系。在模型预测的推动下，我们利用定向进化和酵母表面展示技术来亲和成熟抗1，4，7，10-tetraazacyclododecane-1，4，7，10-tetraacetic酸的2D12.5抗体(DOTA)，重组为单链可变片段(ScFv)。模型预测，对于高抗原密度和饱和bsAb剂量，需要100皮摩尔(Pm)的半抗原结合亲和力才能保持接近最大的半抗原保留。我们亲和成熟了2D12.5，初始结合常数约为10纳摩尔(NM)与DOTA-Y螯合物。亲和力成熟后，对生物素标记的DOTA-Y的亲和力提高了1000倍，得到8.2±1.9皮摩尔的结合。高亲和力的ScFv与具有相似皮摩尔亲和力的钚和Gd的DOTA络合物以及具有低纳摩尔亲和力的铟的络合物结合。当被设计成针对癌胚抗原(CEA)的双特异性抗体构建物时，在异种移植小鼠模型中，预靶向高亲和力单链抗体与预靶向野生型单链抗体相比，可显著提高111In-DOTA半抗原的肿瘤保留率。我们设计了一种多功能的、高亲和力的DOTA螯合结合单链抗体。我们预计，它将在开发预靶向成像和治疗方案方面证明是有用的，以开发各种放射性金属的潜力。
In pretargeted radioimmunotherapy (PRIT), a bifunctional antibody is administered and allowed to pre-localize to tumor cells. Subsequently, a chelated radionuclide is administered and captured by cell-bound antibody while unbound hapten clears rapidly from the body. We aim to engineer high-affinity binders to DOTA chelates for use in PRIT applications. We mathematically modeled antibody and hapten pharmacokinetics to analyze hapten tumor retention as a function of hapten binding affinity. Motivated by model predictions, we used directed evolution and yeast surface display to affinity mature the 2D12.5 antibody to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), reformatted as a single chain variable fragment (scFv). Modeling predicts that for high antigen density and saturating bsAb dose, a hapten binding affinity of 100 picomolar (pM) is needed for near-maximal hapten retention. We affinity matured 2D12.5 with an initial binding constant of about 10 nanomolar (nM) to DOTA-yttrium chelates. Affinity maturation resulted in a 1000-fold affinity improvement to biotinylated DOTA-yttrium, yielding an 8.2 ± 1.9 picomolar binder. The high-affinity scFv binds DOTA complexes of lutetium and gadolinium with similar picomolar affinity and indium chelates with low nanomolar affinity. When engineered into a bispecific antibody construct targeting carcinoembryonic antigen (CEA), pretargeted high-affinity scFv results in significantly higher tumor retention of a 111In-DOTA hapten compared to pretargeted wild-type scFv in a xenograft mouse model. We have engineered a versatile, high-affinity DOTA-chelate-binding scFv. We anticipate it will prove useful in developing pretargeted imaging and therapy protocols to exploit the potential of a variety of radiometals.
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影响因子：
3.2
作者：
Ashweek, NJ;Coldham, I;Howard, S
通讯作者：
Howard, S
DOI：
10.1039/p19900002567
发表时间：
1990-09-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1
影响因子：
--
作者：
COX, JPL;CRAIG, AS;BOYCE, BA
通讯作者：
BOYCE, BA
影响因子：
6.4
作者：
FENWICK, JR;PHILPOTT, GW;CONNETT, JM
通讯作者：
CONNETT, JM
影响因子：
2.8
作者：
Aime, S;Barge, A;Bombieri, G
通讯作者：
Bombieri, G
影响因子：
12.6
作者：
Blake, DA;Jones, RM;Yu, HN
通讯作者：
Yu, HN