Nakisa Zarrabi-Ahrabi - Science and Research Unit, Islamic Azad University, Tehran, Iran
Shideh Montaser-Kouhsari - Science and Research Unit, Islamic Azad University, Tehran, Iran
Payam Behradkia - Department of Radioisotope, Nuclear Research Center, AOEI, Tehran, Iran
Mohammad Shafiei - Department of Radioisotope, Nuclear Research Center, AOEI, Tehran, Iran

Introduction: Binding a monoclonal antibody to tumor associated antigens is an effective method for cancer therapy because these agents can specifically target malignant cells, in fact monoclonal antibodies are effective agents for diagnosis, grading and treatment of different kinds of cancers. Methods: In this research, a new monoclonal antibody against colon cancer cells was prepared and antigen concentration in different cells determined by a radioimmunoassay method using iodine (I-125) labeled protein G. Results: 125I-labeled protein G percent binding to white blood cell, HT29, LS180 and MCF7 cell lines were 7.1%, 91.2%, 75.8% and 40.2%, respectively. Conclusion: Regarding importance of monoclonal antibody applications, it is necessary to find an efficient method for their evaluation in cancer therapy. In this method, a radioactive agent with no count restriction was used. Also by this method, amount of the antigen can be easily quantified.

Hybridoma, Radioimmunoassay technique, Protein G