Chimeric antigen receptors with an optimized hinge region
The present invention relates to multi-functional proteins which comprise (i) a signal peptide, (ii) a target specific recognition domain, (iii) a linker region, connecting domain (ii) and domain (iv) which comprises a specific modified hinge region of the human CD8 alpha-chain, and (iv) an effector domain. The present invention furthermore relates to nucleic acids encoding the proteins, expression constructs for expressing the protein in a host cell and host cells. The proteins of the invention are chimeric antigen receptors with an optimized linker or hinge region that are suitable for generating target-specific effector cells, for use as a medicament, in particular in the treatment of cancer and in adoptive, target-cell specific immunotherapy.
1. A protein comprising
(i) a signal peptide;
(ii) a target specific recognition domain;
(iii) a linker region, connecting the target specific recognition domain and an effector domain, wherein the linker region does not contain cysteine residue(s) and consists of:
a) the amino acid sequence of SEQ ID NO: 2, or
b) an amino acid sequence that differs in one, two or three amino acid residues from the amino acid sequence of SEQ ID NO: 2 under the proviso that amino acid residue 48 is not a cysteine and is a serine; and
(v) the effector domain comprises:
a) a transmembrane domain and an intracellular domain of human costimulatory CD28 receptor fused to an intracellular domain of a zeta-chain of a human CD3 complex of a T-cell receptor, or
b) a zeta-chain of a human CD3 complex of a T-cell receptor with the amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 9.
2. The protein according to claim 1 , wherein the target specific recognition domain (ii) binds to a tumor-associated surface antigen, a lineage-specific or tissue-specific surface antigen or a virus-specific surface antigen.
3. The protein according to claim 1 , wherein the target specific recognition domain (ii) is an antibody or an antigen binding fragment a single chain Fv (scFv) fragment, Fab fragment, a diabody, or a heavy chain variable domain and a light chain variable domain.
4. The protein according to claim 1 , comprising:
a) an amino acid sequence of SEQ ID NO: 7,
b) an amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 12,
c) an amino acid sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 7 under the proviso that amino acid residue no. 308 is not a cysteine and is a serine,
d) an amino acid sequence of SEQ ID NO: 6,
e) an amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 11, or
f) an amino acid sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 6 under the proviso that amino acid residue no. 308 is not a cysteine and is a serine.
5. The protein according to claim 1 , comprising:
a) an amino acid sequence of SEQ ID NO: 5,
b) an amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 10,
c) an amino acid sequence comprising the amino acid residues 29 to 163 of SEQ ID NO: 3, or
d) an amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 9.
6. The protein according to claim 1 , comprising:
a) the amino acid sequence of SEQ ID NO: 2,
b) an amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 8, or
c) an amino acid sequence that differs in one, two or three amino acid residues from the amino acid sequence of SEQ ID NO: 2 under the proviso that amino acid residue 48 is not a cysteine and is a serine.
7. A pharmaceutical composition comprising the protein of claim 1 and a pharmaceutical carrier.