CD22-TARGETED CHIMERIC ANTIGEN RECEPTOR, PREPARATION METHOD THEREFOR AND APPLICATION THEREOF
Provided are a CD22-targeted chimeric antigen receptor, a preparation method therefor and an application thereof. The chimeric antigen receptor comprises a leader sequence, a CD22-targeted scFv, a hinge region, a transmembrane region, and an intracellular signal domain. Provided are a nucleic acid molecule encoding the chimeric antigen receptor and a corresponding expression vector, a CAR-T cell, and an application thereof. The chimeric antigen receptor targets CD22 positive cells and can be used for treating CD22-positive B-cell leukemia, and some CD19-negative and CD22-positive patients in which acute B-cell leukemia has recurred after anti-CD19 CAR-T treatment.
1 . A chimeric antigen receptor (CAR), characterized in that an antigen binding domain (i.e., scFv) of the chimeric antigen receptor comprises an antibody heavy chain variable region shown in SEQ ID NO.: 1 or 3 and an antibody light chain variable region shown in SEQ ID NO.: 2 or 4.
2 . The CAR as described in claim 1 , characterized in that the structure of the antigen binding domain is shown in formula I or II below:
V L -V H (I);
V H -V L (II)
wherein V H is the antigen heavy chain variable region; V L is the antigen light chain variable region; “-” is a linking peptide or peptide bond; preferably, the structure of the antigen binding domain is as shown in formula I.
3 . The CAR as described in claim 2 , characterized in that the amino acid sequence of the V L is shown in SEQ ID NO.: 1, and the amino acid sequence of the V H is shown in SEQ ID NO.: 2.
4 . The CAR as described in claim 2 , characterized in that the amino acid sequence of the V L is shown in SEQ ID NO.: 3, and the amino acid sequence of the V H is shown in SEQ ID NO.: 4.
5 . The CAR as described in claim 1 , characterized in that the structure of the chimeric antigen receptor is shown in formula III below:
L-V L -V H -H-TM-C-CD3ζ (III)
wherein,
L is an optional leader sequence, i.e., a signal peptide;
H is a hinge region;
TM is the transmembrane domain;
C is a costimulatory signal molecule;
CD3ζ is a cytoplasmic signaling sequence derived from CD3ζ; and
V H , V L and “-” are as defined above.
6 . A nucleic acid molecule, characterized in that the nucleic acid molecule encodes the chimeric antigen receptor (CAR) as described in claim 1 .
7 . A vector, characterized in that the vector contains the nucleic acid molecule as described in claim 6 .
8 . A host cell, characterized in that the host cell contains the vector as described in claim 7 or a chromosome integrated with an exogenous nucleic acid molecule as described in claim 6 or expressing the CAR as described in claim 1 .
9 . A formulation, characterized in that the formulation contains the chimeric antigen receptor as described in claim 1 , the nucleic acid molecule as described in claim 6 , the vector as described in claim 7 , or the host cell as described in claim 8 , and a pharmaceutically acceptable carrier, diluent or excipient.
10 . A use of the chimeric antigen receptor as described in claim 1 , the nucleic acid molecule as described in claim 6 , the vector as described in claim 7 , or the host cell as described in claim 8 , or the formulation as described in claim 9 , which is used for preparing a drug or a preparation for preventing and/or treating cancers or tumors.