Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2010, Vol. 21 ›› Issue (2): 84-88 doi: 10.13538/j.1001-8042/nst.21.84-88


Tumor targeting of 125I-labeled anti-EGFR monoclonal antibody LA22 in HT-29 human colon cancer

ZHAO Huiyun JIA Bing WANG Fan LIU Zhaofei*   

  1. Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University, Beijing 100191, China
ZHAO Huiyun, JIA Bing, WANG Fan, LIU Zhaofei. Tumor targeting of 125I-labeled anti-EGFR monoclonal antibody LA22 in HT-29 human colon cancer.Nuclear Science and Techniques, 2010, 21(2): 84-88     doi: 10.13538/j.1001-8042/nst.21.84-88


Epidermal growth factor receptor (EGFR) plays a critical role in proliferation, apoptosis, angiogenesis, invasiveness and distant metastasis of tumors. In this study, the tumor targeting properties of anti-EGFR monoclonal antibody (mAb) LA22 in a colon cancer mouse model are evaluated. The results from flow cytometry assay and immunofluorescent staining clearly showed that HT-29 human colon cancer cells were EGFR positive, and the binding of mAb LA22 to the HT-29 cell surface was specific. The saturation binding experiment of 125I-LA22 to HT-29 cells revealed that LA22 possessed moderate affinity to EGFR with the Kd value calculated to be 3.28±0.76 nM. The in vivo γ imaging demonstrated the specific accumulation of 125I-LA22 in HT-29 tumor xenografts. The specific tumor targeting properties of mAb LA22 make it a good candidate for tumor targeted radioimmunotherapy of EGFR-positive tumors when it is labeled with therapeutic nuclides, such as 131I, 177Lu, or 90Y.

Key words: Epidermal growth factor receptor, LA22, Monoclonal antibody, Tumor targeting, Gamma imaging