Ultra high affinity neutralizing antibodies
Ultra high affinity antibodies with binding affinities in the range of 10 10 M −1 , and even 10 11 M −1 are disclosed. Such antibodies include antibodies having novel high affinity complementarity determining regions (CDRs), especially those with framework and constant regions derived from either humans or mice. Methods of preparing and screening such antibodies, as well as methods of using them to prevent and/or treat disease, especially virus-induced diseases, are also disclosed.
1. A method for preventing a respiratory syncytial virus (RSV)-induced disease, comprising administering to a patient a high affinity neutralizing immunoglobulin that specifically binds to a RSV F antigen with an affinity constant (K a ) of at least 10 10 M −1 as measured by surface plasmon resonance, wherein the high affinity neutralizing immunoglobulin binds to the same epitope on the RSV F antigen as an antibody comprising a heavy chain variable region (VH) having an amino acid sequence SEQ ID NO:2 ( FIG. 1B ) and a light chain variable region (VL) having the amino acid sequence SEQ ID NO:1 ( FIG. 1A ).
2. A method for treating a respiratory syncytial virus-induced disease, comprising administering to a patient a high affinity neutralizing immunoglobulin that specifically binds to a RSV F antigen with a K a of at least 10 10 M −1 as measured by surface plasmon resonance, wherein the high affinity neutralizing immunoglobulin binds to the same epitope on the RSV F antigen as an antibody comprising a VH having the amino acid sequence SEQ ID NO:2 ( FIG. 1B ) and a VL having an amino acid sequence SEQ ID NO:1 ( FIG. 1A ).
3. The method of claims 1 or 2 , wherein the immunoglobulin comprises one or more amino acid changes in one or more complementarity determining regions (CDRs) as compared to an existing antibody, wherein the existing antibody comprises:
a. a VL comprising the following CDR sequences:
VL CDR1 SASSSVGYMH (SEQ ID NO: 3),
VL CDR2 DT KLAS (SEQ ID NO: 4), and
VL CDR3 FQGS YPFT (SEQ ID NO 5); and
b. a VH comprising the following CDR sequences:
VH CDR1 T GMSVG (SEQ ID NO: 6),
VH CDR2 DIWWDDKKDYNPSLKS (SEQ ID NO: 7), and
VH CDR3 SMITN YFDV (SEQ ID NO: 8),
and wherein one or more amino acid residue substitutions are made at the boxed positions, such that the amino acid substitutions have the effect of producing an increase in the K a of the antibody.
4. The method of claims 1 or 2 , wherein the immunoglobulin has a K a of at least 10 11 M −1 .
5. The method of claim 3 , wherein the immunoglobulin has a K a of at least 10 11 M −1 .
6. The method of claim 1 or 2 , wherein the immunoglobulin neutralizes RSV as measured by a microneutralization assay.
7. The method of claim 3 , wherein the immunoglobulin neutralizes RSV as measured by a microneutralization assay.
8. The method of claim 4 , wherein the immunoglobulin neutralizes RSV as measured by a microneutralization assay.
9. The method of claim 6 , wherein the immunoglobulin has an IC 50 in the microneutralization assay that is less than the IC 50 of the IX-493 antibody.
10. The method of claim 7 , wherein the immunoglobulin has an IC 50 in the microneutralization assay that is less than the IC 50 of the IX-493 antibody.
11. The method of claim 8 , wherein the immunoglobulin has an IC 50 in the microneutralization assay that is less than the IC 50 of the IX-493 antibody.
12. The method of claim 1 or 2 , wherein the immunoglobulin comprises:
a. a VH CDR1 having the amino acid sequence TAGMSVG (SEQ ID NO:9);
b. a VH CDR2 having the amino acid sequence DIWWDDKKDYNPSLKS (SEQ ID NO:7);
c. a VH CDR3 having the amino acid sequence SMITNFYFDV (SEQ ID NO:11);
d. a VL CDR1 having the amino acid sequence SASSSVGYMH (SEQ ID NO:3);
e. a VL CDR2 having the amino acid sequence DTFKLAS (SEQ ID NO:12); and
f. a VL CDR3 having the amino acid sequence FQGSFYPFT (SEQ ID NO: 14).
13. The method of claim 1 or 2 , wherein the immunoglobulin is a tetrameric antibody, a Fab fragment, an F(ab)′ 2 , a heavy-light chain dimer, or a single chain structure.
14. The method of claim 1 or 2 , wherein the immunoglobulin is a monoclonal antibody.
15. The method of claim 1 or 2 , wherein the immunoglobulin is a humanized antibody.
16. The method of claim 12 , wherein the immunoglobulin further comprises:
(a) a framework region of a VL having the amino acid sequence of SEQ ID NO:1 and framework region of a VH having the amino acid of SEQ ID NO:2;
(b) a framework region of a VL having the amino acid sequence of SEQ ID NO: 17 and framework region of a VH having the amino acid of SEQ ID NO:18;
(c) a framework region of a VL having the amino acid sequence of SEQ ID NO: 19 and framework region of a VH having the amino acid of SEQ ID NO:20;
(d) a framework region of a VL having the amino acid sequence of SEQ ID NO:21 and framework region of a VH having the amino acid of SEQ ID NO:22;
(e) a framework region of a VL having the amino acid sequence of SEQ ID NO:23 and framework region of a VH having the amino acid of SEQ ID NO:24; or
(f) a framework region of a VL having the amino acid sequence of SEQ ID NO:25 and framework region of a VH having the amino acid of SEQ ID NO:26.
17. The method of claim 1 or 2 , wherein the immunoglobulin comprises a light chain variable region having the amino acid sequence of SEQ ID NO:23 and a heavy chain variable region having the amino acid sequence of SEQ ID NO:24.
18. The method of claim 1 or 2 , wherein the patient is a human.
19. The method of claim 3 , wherein the patient is a human.
20. The method of claim 4 , wherein the patient is a human.
21. The method of claim 6 , wherein the patient is a human.
22. The method of claim 8 , wherein the patient is a human.
23. The method of claim 5 , wherein the patient is a human.
24. The method of claim 7 , wherein the patient is a human.
25. The method of claim 5 , wherein the immunoglobulin neutralizes RSV as measured by a microneutralization assay.
26. The method of claim 25 , wherein the patient is a human.
27. The method of claim 3 , wherein the immunoglobulin is a monoclonal antibody.
28. The method of claim 3 , wherein the immunoglobulin further comprises:
(a) a framework region of a VL having the amino acid sequence of SEQ ID NO:1 and framework region of a VH having the amino acid of SEQ ID NO:2;
(b) a framework region of a VL having the amino acid sequence of SEQ ID NO:17 and framework region of a VH having the amino acid of SEQ ID NO:18;
(c) a framework region of a VL having the amino acid sequence of SEQ ID NO:19 and framework region of a VH having the amino acid of SEQ ID NO:20;
(d) a framework region of a VL having the amino acid sequence of SEQ ID NO:21 and framework region of a VH having the amino acid of SEQ ID NO:22;
(e) a framework region of a VL having the amino acid sequence of SEQ ID NO:23 and framework region of a VH having the amino acid of SEQ ID NO:24; or
(f) a framework region of a VL having the amino acid sequence of SEQ ID NO:25 and framework region of a VH having the amino acid of SEQ ID NO:26.
29. The method of claim 1 or 2 , wherein the Ka is 10 10 −M −1 .
30. The method of claim 3 , wherein the Ka is 10 10 −M −1 .
31. The method of claim 1 or 2 , wherein the Ka is 10 11 −M −1 .
32. The method of claim 3 , wherein the Ka is 10 11 −M −1 .