MAG_3和DTPA用于^(99)Tc^m标记Survivin ASON的对比研究  

The comparative study of influence of MAG_3 and DTPA on preparing ^(99)Tc^m-Survivin ASON

作　　者：高再荣[1] 张凯军[1] 张永学[1] 

机构地区：[1]华中科技大学同济医学院附属协和医院核医学科,武汉430022

出　　处：《中华核医学杂志》2004年第4期238-241,共4页Chinese Journal of Nuclear Medicine

基　　金：湖北省科技厅自然科学基金资助项目 (2 0 0 2AB1 2 1 )

摘　　要：目的　比较巯基乙酰基三甘氨酸 (MAG3)和二乙烯三胺五乙酸 (DTPA)对99Tcm 标记Sur vivin反义寡核苷酸 (SurvivinASON)的影响。方法　用DNA合成仪合成 18碱基单链SurvivinASON ,在5′末端经氨基修饰后 ,分别用S 乙酰基 N 羟基琥珀酰亚胺 MAG3(S acetyl NHS MAG3)和环DTPA酸酐作为螯合剂 ,进行99Tcm 标记 ,并对其标记率、放化纯、比活度、稳定性、细胞摄取率和细胞清除率进行比较。结果　99Tcm MAG3 ASON和99Tcm DTPA ASON的标记率分别为 (6 5 2 2± 6 87) %和 (5 0 5 6±5 4 5 ) % ;放化纯分别为 94 %和 95 % ;比活度分别为 1190和 86 0kBq μg。室温条件下 ,与生理盐水保温 4h后 ,其放化纯均 >90 % ;与正常人血清保温 4h后 ,2种标记寡核苷酸均未见明显血清蛋白质结合。99Tcm MAG3 ASON在肝癌细胞中的摄取率高于99Tcm DTPA ASON(P <0 0 1) ,但两者在肝癌细胞中的摄取均明显高于正常肝细胞 (P <0 0 1)。结论　采用S acetyl NHS MAG3和环DTPA酸酐为螯合剂 ,用99Tcm 标记SurvivinASON可行 ,前者螯合效果优于后者。Objective To investigate the influence of different chelators on preparing 99 Tc m-Survivin antisense oligonucleotide (ASON). Methods An 18 mer single-stranded ASON sequence was synthesized and linked with a primary amine on the 5′-end. The Survivin ASON was labeled with 99 Tc m by conjugating the chelator,S-acetyl-NHS-mercaptoacetyltriglycine (MAG_3) or cyclic DTPA anhydride,respectively. The properties of 99 Tc m-MAG_3-ASON and 99 Tc m-DTPA-ASON,such as radiolabeling efficiency,radiochemical purity,specific activity,accumulation in hepatocellular cancer cells (HCC) and normal liver cells,were studied. Results The radiolabeling efficiency,radiochemical purity and specific activity of 99 Tc m-MAG_3-ASON and 99 Tc m-DTPA-ASON were (65.22±6.87)% and (50.56±5.45)%,94% and 95%,1190 and 860 kBq/μg,respectively. After incubation with normal saline at room temperature for 4 h,the radiochemical purities of both radiolabeled ASONs were more than 90%. No evidence for serum protein binding of the two labeled ASONs was observed after incubation with fresh human serum at 37 ℃ in 5% CO_2 for 4 h. The accumulation rate in HCCs of 99 Tc m-MAG_3-ASON was higher than that of 99 Tc m-DTPA-ASON(P<0.01). The accumulation of both Survivin ASONs in HCCs was significantly higher than that in normal liver cells (P<0.01). Conclusion The labeling methods of Survivin ASON with 99 Tc m,conjugated by S-acetyl-NHS-MAG_3 or cyclic DTPA anhydride,were proved to be successful. Of the two chelators,S-acetyl-NHS-MAG_3 is more suitable for the radiolabeling of Survivin ASON with 99 Tc m.

关 键 词：^99TC^M标记 ^99TC^M-DTPA MAG 标记率 肝癌细胞 NHS 对比研究 酸酐 二乙烯三胺 琥珀酰亚胺 

分 类 号：R817[医药卫生—影像医学与核医学] R735.7[医药卫生—放射医学]