Monoclonal antibody-cytokine fusion protein dimer and application thereof
Provided are a monoclonal antibody-cytokine fusion protein dimer and an application thereof. The monoclonal antibody comprises two heavy chains, the fusion protein dimer comprises a first heavy chain polypeptide chain and a second heavy chain polypeptide chain, wherein one heavy chain of the monoclonal antibody is connected to a cytokine to form the first heavy chain polypeptide chain, and the other heavy chain of the monoclonal antibody is optionally connected to another cytokine to form the second heavy chain polypeptide chain. The monoclonal antibody-cytokine fusion protein dimer provided not only fully retains the biological activity of the antibody, but also significantly improves the biological activity of the cytokine(s). More importantly, by using the target specificity of the antibody molecule, the immune response of immune cells is enhanced and the toxicity of the cytokine(s) is reduced, and thus, on the premise of enhancing the efficacy of the drug, the safety of the medication is ensured.
1 . A monoclonal antibody-cytokine fusion protein dimer, wherein the monoclonal antibody comprises two heavy chains and two associated light chains, the fusion protein dimer comprises a first heavy chain polypeptide chain and a second heavy chain polypeptide chain, wherein one heavy chain of the monoclonal antibody is connected with a cytokine to form the first heavy chain polypeptide chain, and the other heavy chain of the monoclonal antibody is connected with another cytokine to form the second heavy chain polypeptide chain, wherein the monoclonal antibody is a full-length anti-PD-1 antibody, wherein the associated light chains each comprise the amino acid sequence of SEQ ID NO:52, and wherein:
the first heavy chain polypeptide chain comprises the amino acid sequence of SEQ ID NO: 60, and the second heavy chain polypeptide chain comprises the amino acid sequence of SEQ ID NO:58;
the first heavy chain polypeptide chain comprises the amino acid sequence of SEQ ID NO: 58, and the second heavy chain polypeptide chain comprises the amino acid sequence of SEQ ID NO:56; or
the first heavy chain polypeptide chain comprises the amino acid sequence of SEQ ID NO: 62, and the second heavy chain polypeptide chain comprises the amino acid sequence of SEQ ID NO:56.
2 . The monoclonal antibody-cytokine fusion protein dimer according to claim 1 , wherein one heavy chain of the monoclonal antibody is connected with cytokine IL-12 to form the first heavy chain polypeptide chain, and the other heavy chain of the monoclonal antibody is connected with the cytokine IL-2 or an IL-2 mutant to form the second heavy chain polypeptide chain.
3 . The monoclonal antibody-cytokine fusion protein dimer according to claim 2 , wherein the monoclonal antibody is connected with the cytokines through Fc regions of the heavy chains.
4 . The monoclonal antibody-cytokine fusion protein dimer according to claim 3 , wherein the Fc regions of the two heavy chains of the monoclonal antibody are different and have an asymmetric complementary structure therebetween.
5 . The monoclonal antibody-cytokine fusion protein dimer according to claim 4 , wherein the Fc region of any one heavy chain of the monoclonal antibody has a mutation combination T366W/S354C, and the Fc region of the other complementary heavy chain has a mutation combination T366S/L368A/Y407V/Y349C.
6 . The monoclonal antibody-cytokine fusion protein dimer according to claim 2 , wherein the IL-12 has an amino acid sequence of SEQ ID NO:4.
7 . The monoclonal antibody-cytokine fusion protein dimer according to claim 2 , wherein the monoclonal antibody and the cytokines are connected through the linker sequence or directly fused.
8 . The monoclonal antibody-cytokine fusion protein dimer according to claim 7 , wherein the linker sequence is selected from (S(G 4 S) 1-3 ) (SEQ ID NO:64), (G 4 S) 1-3 (SEQ ID NO:65), KRVAPELLGGPS (SEQ ID NO:66), ASTKG (SEQ ID NO:67), NSPPAA (SEQ ID NO:68), EPKSSDKTHTSPPSP (SEQ ID NO:69), ERKSSVESPPSP (SEQ ID NO:70) and ESKYGPPSPPSP (SEQ ID NO:71).
9 . An isolated polynucleotide, encoding the monoclonal antibody-cytokine fusion protein dimer according to claim 2 .
10 . An expression vector comprising the polynucleotide according to claim 9 .
11 . A host cell comprising the expression vector of claim 10 .
12 . An anti-tumor pharmaceutical composition, comprising the monoclonal antibody-cytokine fusion protein dimer according to claim 2 and a pharmaceutically acceptable carrier.
13 . An isolated polynucleotide, encoding the monoclonal antibody-cytokine fusion protein dimer according to claim 1 .
14 . An expression vector comprising the polynucleotide according to claim 13 .
15 . A host cell comprising the polynucleotide according to claim 13 .
16 . A method of treating a tumor, comprising administrating to the subject a therapeutically effective amount of the monoclonal antibody-cytokine fusion protein dimer according to claim 2 .