Poly(ethylene glycol)-avidin bioconjugates: suitable candidates for tumor pretargeting
Poly(ethylene glycol)-avidin bioconjugates: suitable candidates for tumor pretargeting
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DOI：
10.1016/s0168-3659(02)00199-2
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发表时间：
2002-09-18
影响因子：
10.8
通讯作者：
Paganelli, G
中科院分区：
文献类型：
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作者：
Caliceti, P;Chinol, M;Paganelli, G
抗生物素蛋白-聚（乙二醇）（PEG）缀合物通过用线性5 kDa PEG或支链10或20 kDa PEG衍生约10%的蛋白质氨基（每个蛋白质分子4个氨基）获得。圆二色性分析表明，聚合物共轭既不改变蛋白质结构，也不改变存在于生物素结合位点水平的芳香族氨基酸的环境。进行了光谱研究，以评估生物素结合位点的数量或抗生物素蛋白/生物素亲和力方面的缀合物的生物素识别活性。抗生物素蛋白-PEG 5 kDa和抗生物素蛋白-PEG 10 kDa显示出超过90%的天然蛋白生物活性，而PEG 20 kDa发现生物素化抗体的识别减少约25%。体内实验表明，该蛋白的免疫原性顺序为：野生型亲和素>亲和素-PEG 5 kDa>亲和素-PEG 10 kDa>亲和素-PEG 20 kDa。通过静脉注射到携带实体瘤的小鼠中，所有缀合物相对于天然蛋白质在循环中显示出延长的持久性。抗生物素蛋白-PEG 5 kDa、抗生物素蛋白-PEG 10 kDa和抗生物素蛋白-PEG 20 kDa的曲线下面积值比野生型抗生物素蛋白高约3倍、7倍和30倍，在肾脏和肝脏中的积累减少。有趣的是，所有缀合物在肿瘤块中显著累积。特别是，在抗生物素蛋白-PEG 20 kDa的情况下，在给药5 μ l后肿瘤中累积了注射剂量（ID）/g组织的8%，并且在整个72小时内维持了超过6%的ID/g。(C)2002 Elsevier Science B. V.保留所有权利。
Avidin-poly(ethylene glycol) (PEG) conjugates were obtained by derivatization of about 10% of the protein amino groups (four amino groups per protein molecule) with linear 5 kDa PEG or branched 10 or 20 kDa PEGs. Circular dichroism analysis showed that the polymer conjugation neither altered the protein structure nor the environment of the aromatic amino acids which are present at the level of the biotin binding site. Spectroscopic studies were carried out to evaluate the biotin recognition activity of the conjugates either in terms of number of biotin binding sites or avidin/biotin affinity. Avidin-PEG 5 kDa and avidin-PEG 10 kDa displayed over 90% of the native protein biological activity while a reduction in the recognition of biotinylated antibodies of about 25% was found with PEG 20 kDa. In vivo studies demonstrated that the protein immunogenicity was in the order: wild type avidin>avidin-PEG 5 kDa>avidin-PEG 10 kDa>avidin-PEG 20 kDa. By intravenous injection into mice bearing a solid tumor, all conjugates displayed prolonged permanence in the circulation with respect to the native protein. The area under the curve values of avidin-PEG 5 kDa, avidin-PEG 10 kDa and avidin-PEG 20 kDa were about 3-, 7- and 30-times higher than the wild type avidin with reduced accumulation in kidneys and liver. Interestingly, all conjugates accumulated significantly in the tumor mass. In particular, in the case of avidin-PEG 20 kDa, 8% of the injected dose (ID)/g of tissue accumulated in the tumor after 5 It from the administration and over 6% of the ID/g was maintained throughout 72 h. (C) 2002 Elsevier Science B.V. All rights reserved.