Abstract: Provided in the present application are an antibody against factor XIa in the activated form of coagulant factor XI, a preparation method therefor and the use thereof. The CDR of the heavy chain variable region of the antigen-binding fragment of the antibody comprises the amino acid sequence shown in SEQ ID NOs: 1-3, and the CDR of the light chain variable region thereof comprises the amino acid sequence shown in SEQ ID NOs: 4-6. The antibody can specifically bind to FXIa but not to FXI, and has the effect of inhibiting the endogenous pathway of human coagulation without affecting the exogenous pathway thereof, which can significantly inhibit the formation of arteriovenous shunt thrombosis, but does not increase the bleeding time and volume. Same has the potential to become an antithrombotic drug.

Abstract: The present invention provides an anti-B7H4 antibody-drug conjugate specifically binding to B7H4, and a composition comprising same, wherein the structure of the anti-B7H4 antibody-drug conjugate is shown as formula (I-1). The present invention further provides a method and use of the antibody-drug conjugate provided herein. The anti-B7H4 antibody-drug conjugate of the present invention has better inhibitory activity against tumor cell proliferation in vitro and a better tumor inhibition effect in vivo.

Abstract: Provided in the present application are an antibody against factor XIa in the activated form of coagulant factor XI, a preparation method therefor and the use thereof. The CDR of the heavy chain variable region of the antigen-binding fragment of the antibody comprises the amino acid sequence shown in SEQ ID NOs: 1-3, and the CDR of the light chain variable region thereof comprises the amino acid sequence shown in SEQ ID NOs: 4-6. The antibody can specifically bind to FXIa but not to FXI, and has the effect of inhibiting the endogenous pathway of human coagulation without affecting the exogenous pathway thereof, which can significantly inhibit the formation of arteriovenous shunt thrombosis, but does not increase the bleeding time and volume. Same has the potential to become an antithrombotic drug.