新型磁共振靶向对比剂Gd-DTPA-链霉亲和素的制备及其反应条件的实验研究

南方医科大学学报 ›› 2004, Vol. 24 ›› Issue (01): 15-17.

新型磁共振靶向对比剂Gd-DTPA-链霉亲和素的制备及其反应条件的实验研究

刘岘, 许乙凯, 黄其鎏

第一军医大学南方医院影像中心, 广东, 广州, 510515

出版日期:2004-01-20 发布日期:2004-01-20
基金资助:
收稿日期:2003-5-26。
基金项目:国家自然科学基金(30371608);广东省自然科学基金(020053)
作者简介:刘岘(1974- ),男,2001年毕业于第一军医大学,现为在读博士研究生,电话:020-61642086,E-mail:liuxian@fimmu.com

Preparation of a novel targeted MR contrast agent Gd-DTPA-streptavidin and exploration of its reaction conditions

LIU Xian, XU Yi-kai, HUANG Qi-liu

第一军医大学南方医院影像中心, 广东, 广州, 510515

Online:2004-01-20 Published:2004-01-20

摘要/Abstract

摘要： 目的探讨制备Gd3⁺标记的二乙三胺五乙酸-链霉亲和素(Gd-DTPA-SA)的最佳反应条件。方法选择不同pH值的反应体系(pH值分别为5、6、7、8)及不同DTPA-SA的摩尔比率(1000、500、200、100),测定不同反应条件下的每个SA分子所结合的Gd3⁺数目及Gd-DTPA-SA的结合活性。结果随着反应体系pH值的增高,每个SA分子所结合的Gd3⁺数目增高;当DTPA-SA摩尔比率低于500时,DTPA-SA联结Gd的数目随着DTPA-SA摩尔比的增高而增高;而当摩尔比率为1 000时,则出现下降。各实验组Gd-DTPA-SA复合物的生物素结合活性无明显差异。结论 SA分子所结合的Gd3⁺数目依赖于反应体系的pH值及DTPA环酐-蛋白的摩尔比值,而Gd-DTPA-SA的生物素结合活性与反应条件无关。

Abstract: Objective To explore the optimal reaction condition of D TP A-coupled streptavidin labeled with gadolinium ion.Methods The number streptav idin-coupled of gadolinium ions and maximum biotin-binding capacity of Gd-DTPA-S A complex were analyzed at different DTPA-to-SA molar ratios (1000, 500, 200, 100) and in buffer solutions of different pH values (pH 5, 6, 7, and 8, respectiv ely).Results The number of streptavidin-coupled gadolinium ions increased with the pH value of the reaction system. When the DTPA-to-SA molar ratio was below 500, the number of gadolinium ions that SA-DTPA coupled increased with the DTPA -to-SA molar ratio, but tended to decrease when the ratio was 1000. No signific ant difference in the maximum biotin-binding capacity of Gd-DTPA-SA complex was noted between the groups.Conclusion The number of gadolinium ions that s treptavidin coupled depends on the pH value of the reaction system and DTPA-to-S A molar ratio, but the maximum biotin-binding capacity of Gd-DTPA-SA complex is not affected by the reaction conditions.

中图分类号:

刘岘, 许乙凯, 黄其鎏. 新型磁共振靶向对比剂Gd-DTPA-链霉亲和素的制备及其反应条件的实验研究[J]. 南方医科大学学报, 2004, 24(01): 15-17.

LIU Xian, XU Yi-kai, HUANG Qi-liu. Preparation of a novel targeted MR contrast agent Gd-DTPA-streptavidin and exploration of its reaction conditions[J]. Journal of Southern Medical University, 2004, 24(01): 15-17.

参考文献

[1] 许乙凯.磁共振对比剂的发展概况及存在问题[J].第一军医大学学报,2002,22(9):769-71.Xu YK. Contrast agents in magnetic resonance imaging:development and problems[J]. J First Mil Med Univ/Di Yi Jun Yi Da Xue Xue Bao,2002,22(9):769-71.
[2] 刘岘,许乙凯,黄其鎏,等.使用SPIO对大鼠肝癌模型进行MR增强显像的实验研究[J].第一军医大学学报,2002,22(12):1061-5.Liu X,Xu YK,Huang QL,et al. Superparamagnetic iron oxideenhanced magnetic resonance imaging of hepatocellular carcinoma in rats[J]. J First Mil Med Univ/Di Yi Jun Yi Da Xue Xue Bao,2002,22(12):1061-5.
[3] Paik CH,Ebert MvA,Murphy PR,et al. Factors influencing DTPA conjugation with antibody by cyclic DTPA anhydride[J]. J Nucl Med,1983,24 (12):1158-63.
[4] Paik CH,Murphy PR,Eckelman WC,et al. Optimization of the DTPA mixed-anhydride reaction with antibody at low concentration[J]. JNucl Med,1983,24 (10):932-6.
[5] Sakahara H,Endo K,Nakashima T,et al. Effect of DTPA conjugation on the antigen binding activity and biodistribution of monoclonal antibodies against α-Fetoprotein[J]. J Nucl Med,1985,26 (7):751-5.
[6] Hnatowich DJ,Childs RL,Lanteigne D,et al. The preparation of DTPA-coupled antibodies radiolabeled with metallic radionuclides:an improved method[J]. J Immun Methods,1983,65 (1):147-57.
[7] Kobayashi H,Wu C,Yoo TM,et al. Evaluation of the in vivo biodistribution of yttrium-labeled isomers of CIIX-DTPA-conjugated monoclonal antibody[J]. J Nucl Med,1998,39 (5):829-36.
[8] Paik CH,Hong JJ,Ebbert MA,et al. Relative reactivity of DTPA,immunoreactive antibody-DTPA conjugates,and nonimmunoreactive antibody-DTPA conjugates toward indium-111[J]. J Nucl Med,1985,26 (5):482-7.
[9] Gitlin G,Khait I,Bayer EA,et al. Studies on the biotin-binding sites ofavidin and streptavidin:a chemically induced dynamic nuclear polarization investigation of the status of tyrosine residues[J].Biochem J,1989,259 (2):493-8.
[10] Wilchek M,Bayer EA. Introduction to avidin-biotin technology[J].Methods Enzymol,1990,184 (1):5-13.
[11] Wilchek M,Bayer EA. Applications of avidin-biotin technology:,literature survey[J]. Methods Enzymol,1990,184 (1):14-45.
[12] Chen L,Schechter B,Arnon R,et al. Tissue selective affinity targeting using the avidin-biotin system[J]. Drug Dev Res,2000,50 (1):258-71.