Screening of a novel CD47-blocking monoclonal antibody and observation of its anti-colorectal cancer activity
LU Yang
YUAN Xiangfei
ZHANG Yanjun
FAN Dongmei
XIONG Dongsheng
Abstract：Objective To screen a novel blocking monoclonal antibody targeting human CD47 protein and to ob-serve its anti-colorectal cancer activity,providing a new option for immunotherapy targeting the human CD47 target.Methods We obtained a murine hybridoma cell line that stably secreted CD47 antibodies using monoclonal antibody screening technology.Ascites were prepared in mice,and the purified antibody 47-F was obtained.The binding affinity of 47-F to CD47 protein was assessed using flow cytometry,and its competitive binding with the commercial CD47 antibody B6H12.2 to target cells was evaluated.Hemagglutination assay was conducted to determine the erythrocyte toxicity of 47-F.Human macrophages derived from peripheral blood mononuclear cells were isolated,and phagocytosis assay was used to observe the in vitro effects of 47-F,B6H12.2,and isotype control antibodies on macrophage-mediated phagocytosis of colorectal cancer cell lines HCT116 and SW620.A subcutaneous colorectal cancer xenograft model in mice was estab-lished,and mice were randomly assigned into the antibody treatment group and PBS control group.The in vivo inhibitory effect of 47-F on tumor growth was evaluated.Results The 47-F antibody effectively bound to CD47 protein with high af-finity and competitively inhibited the binding of the commercial antibody B6H12.2 to human CD47 protein in a concentra-tion-dependent manner.Hemagglutination assay results showed that 47-F did not induce red blood cell agglutination,indi-cating low erythrocyte toxicity.Compared with the control antibody,both 47-F antibody and B6H12.2 antibody significant-ly increased the phagocytosis rates of SW620 and HCT116 cells by human macrophages,with 47-F antibody demonstrating stronger pro-phagocytic activity than B6H12.2 antibody(P<0.05).On day 19 of antibody administration,the tumor vol-ume in the antibody-treated group was significantly smaller than that in the PBS control group(P<0.05),with a tumor inhi-bition rate of 80.6%.Conclusions A novel CD47-blocking monoclonal antibody,47-F,has been successfully identi-fied.This antibody exhibits strong binding affinity,potent pro-phagocytic activity,low erythrocyte toxicity,and robust an-ti-colorectal cancer activity.
Keywords：CD47monoclonal antibodycolorectal carcinomatumor-associated macrophageserythrocytotoxicity
Publication Date：2025-04-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 37-41 )