Hadi Hassannia1, Mohammad Mehdi Amiri2, Farhad Jadidi-Niaragh3, Reza Hosseini-Ghatar1, Jalal Khoshnoodi1, Ramezan-Ali Sharifian4, Forough Golsaz-Shirazi1, Mahmood Jeddi-Tehrani5, Fazel Shokri6. 1. Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 2. Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: m_amiri@tums.ac.ir. 3. Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. 4. Department of Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran. 5. Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran. 6. Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran. Electronic address: fshokri@tums.ac.ir.
Abstract
INTRODUCTION: Immunotherapy with tumor-associated antigens (TAAs) is a potentially powerful approach to eradicate tumor cells. The receptor tyrosine kinase-like orphan receptor 1 (ROR1) plays a crucial role for survival of tumor cells and is overexpressed in various malignancies. In the present study, we developed a syngeneic mouse tumor model to assess anti-tumor effect of mouse ROR1 specific polyclonal antibody (pAb) in vivo. MATERIALS AND METHODS: Mouse ROR1 specific antibody was produced in rabbit using recombinant ROR1 protein. Tow mouse tumor cell lines, (4T1 and CT26), were transfected with full length mouse ROR1 construct and stable clones were selected and characterized by immunocytochemistry, Western blot and flow cytometry. In vitro and in vivo anti-tumor activities of anti-ROR1 antibody were assessed by XTT and syngeneic BALB/c mouse model, respectively. RESULTS: We successfully established two mouse ROR1-overexpressing tumor cell lines. The in vitro results indicate that the ROR1pAb did not significantly inhibit growth of ROR1+ cell lines. One of these cell lines (CT26-ROR1) was implanted in syngeneic BALB/c mice to assess anti-ROR1 tumor inhibitory activity in vivo. The tumor size was significantly reduced in mice treated with ROR1 specific pAb. CONCLUSION: Our results demonstrated for the first time tumor inhibitory effect of mouse ROR1 specific antibody in a syngeneic mouse tumor model. This model is a promising tool for preclinical assessment of ROR1 therapeutics and investigation of the underling molecular mechanisms.
INTRODUCTION: Immunotherapy with tumor-associated antigens (TAAs) is a potentially powerful approach to eradicate tumor cells. The receptor tyrosine kinase-like orphan receptor 1 (ROR1) plays a crucial role for survival of tumor cells and is overexpressed in various malignancies. In the present study, we developed a syngeneic mousetumor model to assess anti-tumor effect of mouseROR1 specific polyclonal antibody (pAb) in vivo. MATERIALS AND METHODS:MouseROR1 specific antibody was produced in rabbit using recombinant ROR1 protein. Tow mousetumor cell lines, (4T1 and CT26), were transfected with full length mouseROR1 construct and stable clones were selected and characterized by immunocytochemistry, Western blot and flow cytometry. In vitro and in vivo anti-tumor activities of anti-ROR1 antibody were assessed by XTT and syngeneic BALB/c mouse model, respectively. RESULTS: We successfully established two mouseROR1-overexpressing tumor cell lines. The in vitro results indicate that the ROR1pAb did not significantly inhibit growth of ROR1+ cell lines. One of these cell lines (CT26-ROR1) was implanted in syngeneic BALB/c mice to assess anti-ROR1tumor inhibitory activity in vivo. The tumor size was significantly reduced in mice treated with ROR1 specific pAb. CONCLUSION: Our results demonstrated for the first time tumor inhibitory effect of mouseROR1 specific antibody in a syngeneic mousetumor model. This model is a promising tool for preclinical assessment of ROR1 therapeutics and investigation of the underling molecular mechanisms.