Therapeutic agent for malignant tumors expressing MHC class II
View Patent ↗Provided is a novel therapeutic agent specific for a malignant tumor expressing MHC class II. The present invention provides an antibody recognizing a protein constituting MHC class II expressed on a malignant tumor, the antibody comprising at least one selected from heavy chain CDR1 (amino acid sequence represented by positions 49 to 54 of SEQ ID NO: 54), heavy chain CDR2 (amino acid sequence represented by positions 69 to 84 of SEQ ID NO: 54), heavy chain CDR3 (amino acid sequence represented by positions 117 to 128 of SEQ ID NO: 54), light chain CDR1 (amino acid sequence represented by positions 46 to 55 of SEQ ID NO: 56), light chain CDR2 (amino acid sequence represented by positions 71 to 77 of SEQ ID NO: 56), and light chain CDR3 (amino acid sequence represented by positions 100 to 108 of SEQ ID NO: 56).
1. An antibody recognizing a MHC class II protein expressed on a malignant tumor, the antibody comprising a light chain CDR1 (amino acid sequence represented by positions from 49 to 54 of SEQ ID NO: 54), a light chain CDR2(amino acid sequence represented by positions from 69 to 84 of SEQ ID NO: 54), a light chain CDR3 (amino acid sequence represented by positions from 117 to 128 of SEQ ID NO: 54), a heavy chain CDR1 (amino acid sequence represented by in positions from 46 to 55 of SEQ ID NO: 56), a heavy chain CDR2 (amino acid sequence represented by positions from 71 to 77 of SEQ ID NO: 56), and a heavy chain CDR3 (amino acid sequence represented by positions from 100 to 108 of SEQ ID NO: 56).
2. The antibody according to claim 1 , comprising:
a light chain having a light chain variable region comprising an amino acid sequence in positions from 19 to 143 of SEQ ID NO: 54,
wherein one or several amino acids within the framework region of the amino acid sequence of SEQ ID NO: 54 are optionally deleted, substituted, added, or a combination thereof.
3. The antibody according to claim 1 , comprising:
a heavy chain having a heavy chain variable region comprising an amino acid sequence in positions from 23 to 132 of SEQ ID NO: 56
wherein one or several amino acids within the framework region of the amino acid sequence of SEQ ID NO: 56 are optionally deleted, substituted, added, or a combination thereof.
4. The antibody according to claim 1 ,
wherein the antibody has a specific cytotoxic activity against the malignant tumor.
5. The antibody according to claim 1 ,
wherein the malignant tumor expressing the MHC class II protein is malignant lymphoma.
6. The antibody according to claim 1 ,
wherein the MHC class II protein is at least one member selected from the group consisting of HLA-DPβ, HLA-DQβ, and HLA-DRβ.
7. The antibody according to claim 6 ,
wherein the MHC class II protein is HLA-DRβ.
8. A pharmaceutical composition, comprising:
the antibody according to claim 1 .
9. A therapeutic agent, comprising:
the antibody according to claim 1 as an active ingredient,
wherein the therapeutic agent is suitable for the malignant tumor expressing the MHC class II protein.
10. A reagent, comprising:
the antibody according to claim 1 ,
wherein the reagent is suitable for detecting the malignant tumor expressing the MHC class II protein.
11. A method for treating the malignant tumor expressing the MHC class II protein, comprising:
administering an effective amount of the antibody according to claim 1 to a subject in need thereof.