Abstract: The present application relates to a modified immune effector cell, wherein the functions of a T cell antigen receptor (TCR) and major histocompatibility complexes (MHCI, MHCII) in the modified immune effector cell are inhibited in a T cell, and the modified immune effector cell comprises a chimeric antigen receptor (CAR) targeting IL13R?2. The modified immune effector cell of the present application knocks out TCR and HLA-A genes expressed by the cell while recognizing surface antigens of tumor cells, so that multiple effects of improving the anti-tumor effect of CAR-T cells, prolonging the survival time of the cells, and reducing the immune rejection response caused by allogeneic cell therapy are achieved.

Abstract: The present application relates to an antigen-binding polypeptide that specifically binds to B7H3, comprising at least one complementarity-determining region (CDR) of an antibody heavy chain variable region (VH), wherein the VH comprises an amino acid sequence set forth in SEQ ID NO: 25. The present application further relates to a chimeric antigen receptor comprising the antigen-binding polypeptide and a universal CAR-T cell comprising the chimeric antigen receptor. The CAR-T cell recognizes a surface antigen of a tumor cell and knocks out TCR and HLA-A genes expressed by the cell at the same time, so that the immune rejection caused by an allogeneic CAR-T therapy is reduced, the survival time of the cell is prolonged, and the anti-tumor effect is improved.

Abstract: The present application relates to an antigen-binding polypeptide that specifically binds to B7H3, comprising at least one complementarity-determining region (CDR) of an antibody heavy chain variable region (VH), wherein the VH comprises an amino acid sequence set forth in SEQ ID NO: 25. The present application further relates to a chimeric antigen receptor comprising the antigen-binding polypeptide and a universal CAR-T cell comprising the chimeric antigen receptor. The CAR-T cell recognizes a surface antigen of a tumor cell and knocks out TCR and HLA-A genes expressed by the cell at the same time, so that the immune rejection caused by an allogeneic CAR-T therapy is reduced, the survival time of the cell is prolonged, and the anti-tumor effect is improved.

Abstract: A modified immune effector cell may be one in which the functions of a T cell antigen receptor (TCR) and major histocompatibility complexes (MHCI, MHCII) in the modified immune effector cell are inhibited in a T cell. Such a modified immune effector cell may include a chimeric antigen receptor (CAR) targeting GD2. Such a modified immune effector cell may knock out TCR and HLA-A genes expressed by the cell while recognizing surface antigens of tumor cells, so that multiple effects of improving the anti-tumor effect of CAR-T cells, prolonging the survival time of the cells, and reducing the immune rejection response caused by allogeneic cell therapy may be reduced.

Abstract: Provided is a modified immune effector cell, wherein compared with the expression and/or activity of the corresponding gene in a corresponding unmodified cell, the expression and/or activity of the TRAC gene and the HLA-A gene are down-regulated, the expression and/or activity of the B2M gene is not down-regulated, and the expression and/or activity of the CIITA gene is not down-regulated. Also provided is a method for preparing the modified immune effector cell.