NEUTRALIZING ANTIBODIES TO GP120 AND THEIR USE
Antibodies and antigen binding fragments that specifically bind to gp120 and neutralize HIV-1 are disclosed. Nucleic acids encoding these antibodies, vectors and host cells are also provided. Methods for detecting HIV-1 using these antibodies are disclosed. In addition, the use of these antibodies, antigen binding fragment, nucleic acids and vectors to prevent and/or treat an HIV-1 infection is disclosed.
1 . An isolated monoclonal antibody, comprising:
a heavy chain variable region (V H ) comprising a heavy chain complementarity determining region (HCDR)1, a HCDR2, and a HCDR3 and an amino acid sequence at least 90% identical to SEQ ID NO: 1; and
a light chain variable region (V L ) comprising a light chain complementarity determining region (LCDR)1, a LCDR2, and a LCDR3 and an amino acid sequence at least 90% identical to SEQ ID NO: 2; and wherein:
the V H comprises:
a tryptophan residue at kabat position 50;
a tyrosine residue at kabat position 54;
an asparagine residue at kabat position 58;
a glycine residues at kabat positions 60-62; and
an arginine residue at kabat position 71; and
the V L comprises:
glycine residues at kabat positions 28 and 30;
a hydrophobic residue at kabat position 91;
a glutamate or glutamine residue at kabat position 96; and
an LCDR3 that is five amino acids in length according to kabat positioning; and
the antibody specifically binds to HIV-1 gp120 and neutralizes HIV-1 infection.
2 . The isolated monoclonal antibody of claim 1 , wherein in aggregate the amino acid sequences of the HCDR1, the HCDR2, the HCDR3, the LCDR1, the LCDR2, and the LCDR3 together comprise up to 10 amino acid substitutions compared to the corresponding CDR sequences of an N6 antibody comprising the V H and V L set forth as SEQ ID NOs: 1 and 2, respectively.
3 . The isolated monoclonal antibody of claim 1 , wherein in aggregate the amino acid sequences of the HCDR1, the HCDR2, the HCDR3, the LCDR1, the LCDR2, and the LCDR3 together comprise up to 5 amino acid substitutions compared to the corresponding CDR sequences of an N6 antibody comprising the V H and V L set forth as SEQ ID NOs: 1 and 2, respectively.
4 . The isolated monoclonal antibody of claim 1 , comprising no more than one amino acid substitution in each CDR compared to the corresponding CDR sequences of an N6 antibody comprising the V H and V L set forth as SEQ ID NOs: 1 and 2, respectively.
5 . The isolated monoclonal antibody of claim 2 , wherein the amino acid substitutions are conservative amino acid substitutions.
6 . The isolated monoclonal antibody of claim 1 , wherein the HCDR1, the HCDR2, the HCDR3, the LCDR1, the LCDR2, and the LCDR3 comprise the consensus amino acid sequences set forth as SEQ ID NOs: 19, 20, 21, 22, 23, and 24, respectively.
7 . The isolated monoclonal antibody of claim 1 , wherein the HCDR1, the HCDR2, the HCDR3, the LCDR1, the LCDR2, and the LCDR3 comprise the amino acids sequences set forth as SEQ ID NOs: 7, 8, 9, 10, 11, and 12, respectively.
8 . The isolated monoclonal antibody of claim 1 , wherein the V H comprises an amino acid sequence at least 95% identical to SEQ ID NO: 1 and the V L comprises amino acid sequence at least 95% identical SEQ ID NO: 2.
9 . The isolated monoclonal antibody of claim 1 , wherein
the V H comprises a VH1-2 germline origin that is from 20-35% divergent from the germline gene;
the V L comprises a IGKV3-11, IGKV3-20, IGKV1-33, or IGLV2 germline origin that is from 15-35% divergent from the corresponding germline gene.
10 . The isolated monoclonal antibody of claim 1 , wherein the antibody is an IgG, IgM or IgA.
11 . The isolated monoclonal antibody of claim 1 , comprising a recombinant constant domain comprising a modification that increases binding to the neonatal Fc receptor, wherein the recombinant constant domain is an IgG1 constant domain comprising M428L and N434S mutations.
12 . An antigen binding fragment comprising the V H and the V L of the isolated monoclonal antibody of claim 1 .
13 . The antigen binding fragment of claim 12 , wherein the antigen binding fragment is a Fv, Fab, F(ab′) 2 , scFV or a scFV 2 fragment.
14 . The isolated monoclonal antibody of claim 1 , wherein the antibody specifically binds to a CD4 binding site on gp120.
15 . The isolated monoclonal antibody of claim 1 , wherein the antibody neutralizes at least 50% of the HIV-1 isolates listed in FIG. 2B (6540.v4.c1, 620345.c1, T278-50, 6322.V4.C1, DU422.01, X2088.c9, 6545.V4.C1, 242-14, T250-4, 7165.18, BL01.DG, HO86.8, 6471.V1.C16, 6631.V3.C10, TVI.29, TZA125.17, CAP210.E8, DU172.17) with an inhibitory concentration (IC 50 ) of <50 μg/ml.
16 . An isolated bispecific antibody comprising the V H and the V L of the isolated human monoclonal antibody of claim 1 .
17 . The isolated bispecific antibody of claim 16 , wherein the antibody specifically binds to gp120 and to CD3.
18 . The isolated monoclonal antibody of claim 1 , linked to an effector molecule or a detectable marker
19 . An isolated nucleic acid molecule encoding the V H , the V L , or V H and the V L of the antibody of claim 1 .
22 . The isolated nucleic acid molecule of claim 19 , comprising a cDNA molecule encoding the V H , the V L , or the V H and the V L .
21 . The isolated nucleic acid molecule of claim 19 , encoding the antibody.
22 . The isolated nucleic acid molecule of claim 19 , encoding a chimeric antigen receptor comprising an extracellular domain, wherein the extracellular domain comprises the V H and the V L .
23 . The isolated nucleic acid molecule of claim 19 , operably linked to a promoter.
24 . An expression vector comprising the nucleic acid molecule of claim 19 .
25 . The expression vector of claim 24 , wherein the expression vector is a viral vector.
26 . The expression vector of claim 25 , wherein the viral vector is an adeno-associated viral vector.
27 . An isolated host cell transformed with the nucleic acid molecule of claim 19 or an expression vector comprising the nucleic acid molecule.
28 . A pharmaceutical composition for use in treating an HIV-1 infection, comprising:
a therapeutically effective amount of the antibody of claim 1 , or an antigen binding fragment of the antibody or a nucleic acid molecule encoding the antibody or antigen binding fragment or an expression vector comprising the nucleic acid molecule; and
a pharmaceutically acceptable carrier.
29 . The pharmaceutical composition of claim 28 , further comprising an additional antibody, antigen binding fragment, or nucleic acid encoding the additional antibody or antigen binding fragment, wherein the additional antibody or antigen binding fragment specifically binds to HIV-1 Env and neutralizes HIV-1 infection.
30 . A method of producing an antibody that specifically binds to HIV-1 gp120, comprising:
expressing a heterologous nucleic acid molecule comprising the nucleic acid molecule of claim 19 in a host cell to produce the antibody; and
purifying the antibody that specifically binds to HIV-1 gp120.
31 . A method of detecting an HIV-1 infection in a subject, comprising:
contacting a biological sample from the subject with the antibody of claim 1 or an antigen binding fragment of the antibody under conditions sufficient to form an immune complex; and
detecting the presence of the immune complex in the sample, wherein the presence of the immune complex in the sample indicates that the subject has the HIV-1 infection.
32 . A method of treating an HIV-1 infection in a subject, comprising administering to the subject a therapeutically effective amount of the antibody of claim 1 or an antigen binding fragment of the antibody or a nucleic acid molecule encoding the antibody or antigen binding fragment or an expression vector comprising the nucleic acid molecule, thereby treating the HIV-1 infection.
33 . The method of claim 32 , wherein the subject is at risk of or has an HIV-1 infection.
34 . The method of claim 32 , further comprising administering to the subject an additional antibody, antigen binding fragment, or nucleic acid encoding the additional antibody or antigen binding fragment, wherein the additional antibody or antigen binding fragment specifically binds to HIV-1 Env and neutralizes HIV-1 infection.