Synthetic antibodies to BAX and uses thereof

Patent metadata

Field	Value
Publication number	US-10294294-B2
Application number	US-201615756997-A
Country	US
Kind code	B2
Filing date	Aug 25, 2016
Priority date	Sep 10, 2015
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

Synthetic fragment antigen-binding (Fab) antibodies are disclosed that bind to an N-terminal activation site of BCL-2-associated X-protein (BAX) and inhibit BAX activation. Also disclosed are methods of using the Fabs for measuring inactive monomeric BAX levels, screening for small molecules that bind to an N-terminal activation site of BAX, inhibiting apoptotic cell death, and predicting the ability of a cancer therapy to promote apoptotic cell death.

First claim

What is claimed is:

1. A synthetic fragment antigen-binding (Fab) antibody that binds to an N-terminal activation site of BCL-2-associated X-protein (BAX) and inhibits BAX activation, wherein the synthetic fragment antigen-binding (Fab) antibody is selected from the group consisting of
2B1 Fab, having a light chain comprising a CDR L1, a CDRL2 and a CDRL3 region comprising the amino acid sequence SEQ ID NO: 1 (QYSGSGHYLI), a CDRH1 region comprising the amino sequence SEQ ID NO: 2 (IYSSSM), a CDRH2 region comprising the amino acid sequence SEQ ID NO: 3 (SISSSSSYTS) and a CDRH3 region comprising the amino acid sequence SEQ ID NO: 4 (RGYWYYWAWWASAMD);
3G11 Fab, having a light chain comprising a CDR L1, a CDRL2 and a CDRL3 region comprising the amino acid sequence SEQ ID NO: 9 (QWSFGPI), a CDRH1 region comprising the amino sequence SEQ ID NO: 10 (ISYYSM), a CDRH2 region comprising the amino acid sequence SEQ ID NO: 11(SIYPYSSSTY) and a CDRH3 region comprising the amino acid sequence SEQ ID NO: 12 (RSSAMD); and
2D9 Fab, having a light chain comprising a CDR L1, a CDRL2 and a CDRL3 region comprising the amino acid sequence SEQ ID NO: 13 (QWSHYLI), a CDRH1 region comprising the amino sequence SEQ ID NO: 14(LYYYSM), a CDRH2 region comprising the amino acid sequence SEQ ID NO: 15 (SISPSYGYTS) and a CDRH3 region comprising the amino acid sequence SEQ ID NO: 16 (RSSFYYYALD).

2. The synthetic Fab antibody of claim 1 , wherein the antibody maintains BAX in its inactive, monomeric form.

3. The synthetic Fab antibody of claim 1 , wherein the antibody binds to residues of helices α1 and α6, and to residues of α1-α2 loop of BAX.

4. The synthetic Fab antibody of claim 1 , wherein the antibody binds to BAX with a half-maximal binding (EC 50 ) affinity of 2 nM-70 nM.

5. The synthetic Fab antibody of claim 1 , wherein the antibody blocks the interaction of BAX with a BAX activating partner.

6. The synthetic Fab antibody of claim 5 , wherein the BAX activating partner is selected from the group consisting of tBID, PUMA, BIM and NOXA.

7. The synthetic Fab antibody of claim 1 , wherein the synthetic Fab antibody is conjugated to a therapeutic agent.

8. The synthetic Fab antibody of claim 1 , wherein the synthetic Fab antibody is conjugated to an agent that facilitates transport across a cell membrane.

9. The synthetic Fab antibody of claim 1 , wherein the synthetic Fab antibody is labeled with a fluorescent label or a radioactive label.

Assignees

• Albert Einstein College Medicine Inc
• The Governing Councel Of The Univ Of Toronto
• Albert Einstein College Medicine
• Governing Council Univ Toronto

Inventors

• Gavathiotis Evripidis
• Lai Jonathan R
• Sidhu Sachdev

Classifications

• G01N33/575

  for cancer · CPC title

• C07K2317/565

  Complementarity determining region [CDR] · CPC title

• G01N2500/04

  Screening involving studying the effect of compounds C directly on molecule A (e.g. C are potential ligands for a receptor A, or potential substrates for an enzyme A) · CPC title

• G01N2510/00

  Detection of programmed cell death, i.e. apoptosis · CPC title

• C07K16/005

  constructed by phage libraries · CPC title