Caninized antibodies to human CTLA-4
The present invention provides caninized anti-human CTLA-4 antibodies that have specific sequences and a high binding affinity for canine CTLA-4. The invention also relates to use of these antibodies in the treatment of cancer in canines and other companion animals.
1 . An isolated caninized antibody or antigen binding fragment thereof that specifically binds canine Cytotoxic T-Lymphocyte-Associated protein 4 (CTLA-4) comprising a canine IgG heavy chain and a canine light chain; wherein the canine light chain comprises three light chain complementary determining regions (CDRs): CDR light 1 (CDRL1), CDR light 2 (CDRL2), and CDR light 3 (CDRL3); and the canine IgG heavy chain comprises three heavy chain CDRs: CDR heavy 1 (CDRH1), CDR heavy 2 (CDRH2) and CDR heavy 3 (CDRH3):
(a) wherein CDRL1 comprises the amino acid sequence of SEQ ID NO: 54;
(b) wherein CDRL2 comprises the amino acid sequence of SEQ ID NO: 56;
(c) wherein CDRL3 comprises the amino acid sequence of SEQ ID NO: 58;
(d) wherein CDRH1 comprises the amino acid sequence of SEQ ID NO: 48;
(e) wherein CDRH2 comprises the amino acid sequence of SEQ ID NO: 50; and
(f) wherein CDRH3 comprises the amino acid sequence of SEQ ID NO: 52;
wherein the isolated caninized antibody or antigen binding fragment thereof blocks the binding of canine CTLA-4 with canine CD80, blocks the binding of canine CTLA-4 with canine CD86, or blocks binding of canine CTLA-4 with both canine CD80 and canine CD86.
2 . The isolated caninized antibody or antigen binding fragment thereof of claim 1 , wherein the canine IgG heavy chain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 60, SEQ ID NO: 62, SEQ ID NO: 64, and SEQ ID NO: 66.
3 . An isolated nucleic acid that encodes the canine IgG heavy chain of the caninized antibody or antigen binding fragment thereof of claim 2 .
4 . An expression vector comprising the isolated nucleic acid of claim 3 .
5 . A host cell comprising the expression vector of claim 4 .
6 . The isolated caninized antibody or antigen binding fragment thereof of claim 2 , wherein the canine light chain is a canine kappa light chain that comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 42, and SEQ ID NO: 46.
7 . An isolated nucleic acid that encodes the canine kappa light chain of the caninized antibody or antigen binding fragment thereof of claim 6 .
8 . An expression vector comprising the isolated nucleic acid of claim 7 .
9 . A host cell comprising the expression vector of claim 8 .
10 . A pharmaceutical composition comprising the caninized antibody or antigen binding fragment thereof of claim 6 , and a pharmaceutically acceptable carrier or diluent.
11 . A method of blocking the binding of canine CTLA-4 with canine CD80, blocking the binding of canine CTLA-4 with canine CD86, or blocking the binding of canine CTLA-4 with both canine CD80 and canine CD86 in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 10 ; wherein the subject has cancer.
12 . A method of blocking the binding of canine CTLA-4 with canine CD80, blocking the binding of canine CTLA-4 with canine CD86, or blocking the binding of canine CTLA-4 with both canine CD80 and canine CD86 in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 10 ; wherein the subject has an infection or infectious disease.
13 . A method of administering a therapeutically effective amount of the pharmaceutical composition of claim 10 to a canine subject.
14 . The isolated caninized antibody or antigen binding fragment thereof of claim 1 , wherein the canine IgG heavy chain comprises the amino acid sequence of SEQ ID NO: 62 and the canine kappa light chain comprises the amino acid sequence of SEQ ID NO: 46.
15 . A pharmaceutical composition comprising the caninized antibody or antigen binding fragment thereof of claim 14 , and a pharmaceutically acceptable carrier or diluent.
16 . A method of blocking the binding of canine CTLA-4 with canine CD80, blocking the binding of canine CTLA-4 with canine CD86, or blocking the binding of canine CTLA-4 with both canine CD80 and canine CD86 in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 15 ; wherein the subject has cancer.
17 . A method of blocking the binding of canine CTLA-4 with canine CD80, blocking the binding of canine CTLA-4 with canine CD86, or blocking the binding of canine CTLA-4 with both canine CD80 and canine CD86 in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 15 ; wherein the subject has an infection or infectious disease.
18 . A method of administering a therapeutically effective amount of the pharmaceutical composition of claim 15 to a canine subject.
19 . A pharmaceutical composition comprising the caninized antibody or antigen binding fragment thereof of claim 1 , and a pharmaceutically acceptable carrier or diluent.
20 . A method of blocking the binding of canine CTLA-4 with canine CD80, blocking the binding of canine CTLA-4 with canine CD86, or blocking the binding of canine CTLA-4 with both canine CD80 and canine CD86 in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 19 ; wherein the subject has cancer.
21 . A method of blocking the binding of canine CTLA-4 with canine CD80, blocking the binding of canine CTLA-4 with canine CD86, or blocking the binding of canine CTLA-4 with both canine CD80 and canine CD86 in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 19 ; wherein the subject has an infection or infectious disease.
22 . A method of administering a therapeutically effective amount of the pharmaceutical composition of claim 19 to a canine subject.
23 . A method of producing a caninized antibody that specifically binds CTLA-4 comprising:
a. culturing host cells that comprise
(i) an expression vector comprising a first nucleic acid encoding a canine IgG heavy chain comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 60, SEQ ID NO: 62, SEQ ID NO: 64, and SEQ ID NO: 66 in a culture medium under conditions wherein the first nucleic acid is expressed, thereby producing a polypeptide that comprises the IgG heavy chain; and
(ii) an expression vector comprising a second nucleic acid encoding a canine kappa light chain that comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 42, and SEQ ID NO: 46 in the culture medium under conditions wherein the second nucleic acid is expressed, thereby producing a polypeptide that comprises the canine kappa light chain; and
b. recovering the caninized antibody from the host cells, the culture medium, or both the host cells and the culture medium.