中文摘要：

用125I和111In标记人源化抗EGFR单克隆抗体Panitumumab,在体外用EGFR阳性细胞UM-SCC-22B测定125I-Panitumumab和111In-DOTA-Panitumumab的放射免疫活性分数,并在正常小白鼠体内进行生物分布研究。研究结果表明,Panitumumab的125I和111In标记均具有较高的标记率,经PD-10纯化后放化纯均高于98%1。25I和111In标记的Panitumumab具有较高的体外免疫活性。生物分布实验数据显示,实验中所有的时间点,111In-DOTA-Panitumumab在肝脏和脾脏中的摄取均显著高于125I标记物,说明不同核素标记对生物分子的体内外性质具有一定的影响。

英文摘要：

Panitumumab（also known as ABX-EGF or Vectibix）,is the first fully human anti-epidermal growth factor receptor（EGFR） monoclonal antibody that was approved by the FDA.Here we labeled Panitumumab with both 125I and 111In,and the in vitro and in vivo behaviors of 125I and 111In labeled Panitumumab were compared.Panitumumab was conjugated with the chelator DOTA for 111In labeling and 125I-Panitumumab was prepared by Iodogen method.The in vitro radioimmunoreactive fractions of 125I/111In-Panitumumab were determined on UM-SCC-22B head and neck cancer cells（EGFR-positive）.Their in vivo biodistribution properties in normal mice were determined.125I or 111In labeled Panitumumab can be prepared with high yield and high radiochemical purity,and both the two radiotracers possess excellent in vitro stability and high immunoreactivity.The uptake of 111In labeled Panitumumab in liver and spleen is significantly higher than those of 125I labeled Panitumumab as determined by biodistribution studies.Our data demonstrates that labeling with different radioisotopes may affect the in vitro and in vivo properties of biological molecules.