ANTIBODIES SPECIFIC FOR IMMUNOGLOBULIN-LIKE TRANSCRIPT 3 (ILT3) AND USES THEREOF
Humanized, non-promiscuous monoclonal antibodies specific for immunoglobulin-like transcript 3 (ILT3), also known as Leukocyte immunoglobulin-like receptor subfamily B member 4 (LILRB4), are described.
1 .- 26 . (canceled)
27 . A nucleic acid molecule encoding an antibody or antigen fragment that binds the extracellular domain of human immunoglobulin-like transcript 3 (ILT3) having amino acids 1-238 of SEQ ID NO: 1, wherein the antibody or antigen binding fragment comprises:
(a) a heavy chain complementarity determining region 1 (HC-CDR1), wherein the HC-CDR1 has the amino acid sequence set forth in SEQ ID NO: 17; an HC-CDR2, wherein the HC-CDR2 has the amino acid sequence set forth in SEQ ID NO: 19, 20, or 21; an HC-CDR3, wherein the HC-CDR3 has the amino acid sequence set forth in SEQ ID NO: 23; and
(b) a light chain complementarity determining region 1 (LC-CDR1), wherein the LC-CDR1 has the amino acid sequence set forth in SEQ ID NO: 34, 35, 36, 37, 38, 39, 40, 41, or 42; an LC-CDR2, wherein the LC-CDR2 has the amino acid sequence set forth in SEQ ID NO: 43; and an LC-CDR3, wherein the LC-CDR3 has the amino acid sequence set forth in SEQ ID NO: 44.
28 . A vector comprising the nucleic acid molecule of claim 27 .
29 . A host cell comprising the vector of claim 28 .
30 . A method for producing an antibody or antigen binding fragment that binds the extracellular domain of human immunoglobulin-like transcript 3 (ILT3) having amino acids 1-238 of SEQ ID NO: 1 comprising:
(a) providing a host cell comprising the vector of claim 28 ;
(b) culturing the host cell in culture medium under conditions to enable expression of the antibody or antigen binding fragment encoded by the vector; and,
(c) obtaining the antibody or antigen binding fragment from the culture medium to provide the antibody or antigen binding fragment.
31 . The nucleic acid molecule of claim 27 , wherein
(a) the HC-CDR1 has the amino acid sequence set forth in SEQ ID NO: 17; the HC-CDR2 has the amino acid sequence set forth in SEQ ID NO:20; and the HC-CDR3 has the amino acid sequence set forth in SEQ ID NO: 23; and
(b) the LC-CDR1 has the amino acid sequence set forth in SEQ ID NO: 41; the LC-CDR2 has the amino acid sequence set forth in SEQ ID NO:43; and, the LC-CDR3 has the amino acid sequence set forth in SEQ ID NO: 44
32 . The nucleic acid molecule of claim 27 , wherein the V H comprises a framework selected from the group consisting of human V H 1, V H 2, V H 3, V H 4, V H S, and V H 6, and variants thereof having 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, additions, deletions, or combinations thereof; and, the V L comprises a framework selected from the group consisting of human V κ 1, V κ 2, V κ 3, V κ 4, V K S, V κ 6, V λ 1, V λ 2, V λ 3, V λ 4, V λ 5, V λ 6, V λ 7, V λ 8, V λ 9, and V λ 10, and variants thereof having 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, additions, deletions, or combinations thereof.
33 . The nucleic acid molecule of claim 27 , wherein the antibody comprises an HC having a human IgG1, IgG2, IgG3, or IgG4 HC constant domain or variant thereof having 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, additions, deletions, or combinations thereof compared to the amino acid sequence of the native IgG1, IgG2, IgG3, or IgG4 isotype constant domain.
34 . The nucleic acid molecule of claim 33 , wherein the antibody comprises an LC having a human kappa or lambda LC constant domain or variant thereof comprising 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, additions, deletions, or combinations thereof compared to the amino acid sequence of the native human kappa or lambda light chain constant domain.
35 . The nucleic acid molecule of claim 31 , wherein the antibody comprises:
(i) a V H having a framework selected from the group consisting of human V H 1, V H 2, V H 3, V H 4, V H S, and V H 6 and a human IgG1 or IgG4 HC constant domain or variant thereof comprising 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, additions, deletions, or combinations thereof compared to the amino acid sequence of the native IgG1 or IgG4 isotype HC constant domain; and,
(ii) a V L having a framework selected from the group consisting of human V κ 1, V κ 2, V κ 3, V κ 4, V K S, V κ 6, V λ 1, V λ 2, V λ 3, V λ 4, V λ 5, V λ 6, V λ 7, V λ 8, V λ 9, and V κ 10 and a human kappa or lambda LC constant domain or variant thereof comprising 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, additions, deletions, or combinations thereof compared to the amino acid sequence of the native human kappa or lambda LC constant domain.
36 . The nucleic acid molecule of claim 32 , wherein the antibody or antigen binding fragment comprises a V H and a V L having the amino acid sequences set forth in SEQ ID NO: 15 and SEQ ID NO: 16, respectively; SEQ ID NO:45 and SEQ ID NO: 46, respectively; SEQ ID NO: 53 and SEQ ID NO: 54, respectively; SEQ ID NO: 61 and SEQ ID NO: 62, respectively; SEQ ID NO: 69 and SEQ ID NO: 70, respectively; SEQ ID NO: 77 and SEQ ID NO: 78, respectively; SEQ ID NO: 85 and SEQ ID NO: 86, respectively; SEQ ID NO: 93 and SEQ ID NO: 94, respectively; or SEQ ID NO:101 and SEQ ID NO: 102, respectively.
37 . The nucleic acid molecule of claim 32 , wherein the antibody or antigen binding fragment comprises a V H having the amino acid sequence set forth in SEQ ID NO: 117, 118, 119, 123, 124, or 125 and a V L having the amino acid sequence set forth in SEQ ID NO: 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, or 141.
38 . The nucleic acid molecule of claim 37 , wherein the antibody or antigen binding fragment comprises a V H having the amino acid sequence set forth in SEQ ID NO: 118 and a V L having the amino acid sequence set forth in SEQ ID NO: 140.
39 . The nucleic acid molecule of claim 35 , wherein the antibody comprises a heavy chain (HC) constant domain comprising the amino acid sequence set forth in SEQ ID NO: 9, 10, 11, 12, or 13.
40 . The nucleic acid molecule of claim 35 , wherein the antibody comprises a light chain (LC) constant domain comprising the amino acid sequence set forth in SEQ ID NO: 14.
41 . The nucleic acid molecule of claim 35 , wherein the antibody comprises a heavy chain (HC) comprising the amino acid sequence set forth in SEQ ID NO: 142, 143, 144, 148, 149, 150, 167, 168, 169, 170, 174, 175, 176, 177, 178, 182, 183, 184, 185, 186, 187, 191, 192, or 193.
42 . The nucleic acid molecule of claim 35 , wherein the antibody comprises a light chain (LC) comprising the amino acid sequence set forth in SEQ ID NO: 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, or 166.
43 . The nucleic acid molecule of claim 35 , wherein the antibody comprises a heavy chain (HC) comprising the amino acid sequence set forth in SEQ ID NO: 143 and a light chain (LC) comprising the amino acid sequence set forth in SEQ ID NO: 165, and variants thereof wherein the HC lacks a C-terminal Lysine residue or a C-terminal glycine-lysine.
44 . A nucleic acid molecule encoding an antibody or antigen binding fragment that binds the extracellular domain of human immunoglobulin-like transcript 3 (ILT3) having amino acids 1-238 of SEQ ID NO: 1, wherein the antibody or antigen binding fragment comprises:
(a) a heavy chain complementarity determining region 1 (HC-CDR1), wherein the HC-CDR1 has the amino acid sequence set forth in SEQ ID NO: 17; an HC-CDR2, wherein the HC-CDR2 has the amino acid sequence set forth in SEQ ID NO: 20; an HC-CDR3, wherein the HC-CDR3 has the amino acid sequence set forth in SEQ ID NO: 23; and
(b) a light chain complementarity determining region 1 (LC-CDR1), wherein the LC-CDR1 has the amino acid sequence set forth in SEQ ID NO: 41; an LC-CDR2, wherein the LC-CDR2 has the amino acid sequence set forth in SEQ ID NO: 43; and an LC-CDR3, wherein the LC-CDR3 has the amino acid sequence set forth in SEQ ID NO: 44.
45 . The nucleic acid molecule of claim 44 , wherein the antibody or antigen binding fragment comprises a V H and a V L having the amino acid sequences set forth in SEQ ID NO: 118 and SEQ ID NO: 140, respectively.
46 . The nucleic acid molecule of claim 45 , wherein the antibody comprises a heavy chain (HC) comprising the amino acid sequence set forth in SEQ ID NO: 143 and a light chain (LC) comprising the amino acid sequence set forth in SEQ ID NO: 165, and variants thereof wherein the HC lacks a C-terminal Lysine residue or a C-terminal glycine-lysine.