Bispecific antigen-binding construct and preparation method and use thereof

Abstract

Disclosed are a bispecific antigen-binding construct and the preparation method and use thereof, wherein the construct comprises a first antigen binding unit and a second antigen binding unit, the first antigen binding unit is a single chain variable region antibody fragment ScFV which specifically binds to the surface antigen of immune cells, and the second antigen binding unit is a Slit2D2 protein fragment which specifically binds to the surface antigen Robo1 of tumour cells. That is to say, the construct can bind to the surface antigen of immune cells and the surface Robo1 molecule of tumour cells at the same time, so that as the distance between tumour cells and immune cells get smaller, the quiescent immune cells are effectively activated, and the effect of killing and wounding tumours is produced. The construct has advantages of small molecular weight and good tissue penetrability, has significant killing and wounding effects on the tumour cells which express a large amount of Robo1, and can be used in the development of anti-tumour drugs.