Preparation, quality control and biodistribution of 99mTc-labeled biotinylated CL3
FAN Yi-xiang
PENG Wu-he
SHI Wei-min
LIU Xiao-bing
Abstract：Objective To prepare 99mTc-labeled biotinylated CL3 (99mTc-CL3-Bt) and study its quality control and biodistribution in rats. Methods Monoclonal antibody (Mab) CL3 binding to biotin was reduced with 2-mercaptoethanol (2-ME) and labeled directly with 99mTc to produce 99mTc-CL3. The immunoactivity of 99mTc-CL3-Bt and 99mTc-CL3 was measured by cell binding test and the results compared; The 2 labeled antibodies were injected into nude mice bearing colorectal cancer xenograft via tail vein at the dosage of 99mTc-CL3-Bt and 99mTc-CL3 respectively. The mice were put to death 6 h later and the percentage of absorbed dose per gram tissue (ID%/g) and its tumor to non-tumor ratio (T/NT) were measured. Results The cell binding rates of 99mTc-CL3-Bt and 99mTc-CL3 were 90% and 94%, and their ID%/g of tumor averaged 6.3±1.1 and 6.7±0.9 respectively, which were statistically comparable (t=0.6293,P>0.05); the ratios of the ID%/g in the tumor to that in the blood were 0.70±0.24 and 0.80±0.12 respectively, showing no significant difference (t=0.8333, P>0.05), either. Conclusion With out decrease of immunoactivity after its preparation, 99mTc-CL3-Bt can be absorbed into the tumor specifically and is applicable in the clinical research of radioimmunoimaging.
Keywords：monoclonal antibodybiotinylationtechnetiumisotope labelingimmunoactivitybiodistribution
Publication Date：2000-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：2( 515-516 )