Experimental study of PD⁃1/PD⁃L1 signal pathway probe targeting osteosarcoma / 安徽医科大学学报

ABSTRACT

Objective @# To explore a non⁃invasive assay for screening osteosarcoma patients with positive programed death receptor⁃1 ( PD⁃1) /programmed death receptor ligand⁃1 ( PD⁃L1) signaling pathway expression @*Methods @#The subcutaneous tumor bearing mouse model of human Osteosarcoma cells ( OS⁃732) was established by the method of tumor formation , and toxicity test was performed to verify the toxicity of PD⁃L1 antibody to mouse organs . 124 I ⁃anti⁃PD⁃L1 monoclonal antibody molecular probe was further synthesized , and OS⁃732 rats were injected with 18 . 5 MBq 124 I ⁃anti⁃PD⁃L1 probe in tail vein to start OS⁃732 osteosarcoma Micro Positron E mission Tomography/ Computed Tomography (Micro⁃PET/CT) imaging. @*Results @#OS⁃732 osteosarcoma model was successfully constructed , immunohistochemistry confirmed the presence of PD⁃L1 expression in OS⁃732 osteosarcoma , and Micro⁃PET/CT imaging was successfully performed at different time points (2 , 24 and 48 h after probe injection) to achieve non⁃invasive real⁃time observation of PD⁃L1 in OS⁃732 osteosarcoma . @*Conclusion @# In this study , the 124 I ⁃anti⁃PD⁃L1 monoclonal antibody molecular probe was constructed in vitro , and Micro PET /CT imaging verified that the probe successfully targeted the PD⁃L1 receptor of OS⁃732 Osteosarcoma , and showed clear immune imaging , indicating that it is hopeful to achieve non⁃invasive screening of Osteosarcoma patients with PD⁃L1 positive expression in clinical practice , and this technology might benefit the majority of Osteosarcoma patients .