Synthetic antibodies to BAX and uses thereof

Patent metadata

Field	Value
Publication number	US-11174308-B2
Application number	US-202016988947-A
Country	US
Kind code	B2
Filing date	Aug 10, 2020
Priority date	Sep 10, 2015
Publication date	Nov 16, 2021
Grant date	Nov 16, 2021

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:
3H4 Fab, having a light chain comprising a CDR L1, a CDRL2, and a CDRL3 region comprising the amino acid sequence of SEQ.ID.No:69, wherein the CDRL3 region comprises QSWYYSYPI (SEQ ID NO: 25), and a heavy chain CDRH1 region comprising the amino sequence LSYSSM (SEQ ID NO: 26), a CDRH2 region comprising the amino acid sequence SISSYYSYTS (SEQ ID NO: 27), and a CDRH3 region comprising the amino acid sequence RYYGYGGGID (SEQ ID NO: 28);
2A6 Fab, having a light chain comprising a CDR L1, a CDRL2, and a CDRL3 region comprising the amino acid sequence of SEQ.ID.NO:75, wherein the CDRL3 region comprises QSAGGYPLI (SEQ ID NO: 29), and a heavy chain CDRH1 region comprising the amino sequence IYYSSM (SEQ ID NO: 30), a CDRH2 region comprising the amino acid sequence SISPYSSYTS (SEQ ID NO: 31), and a CDRH3 region comprising the amino acid sequence RSFGYGWAFD (SEQ ID NO: 32);
3H1 Fab, having a light chain comprising a CDR L1, a CDRL2, and a CDRL3 region comprising the amino acid sequence of SEQ.ID.NO:67, wherein the CDRL3 region comprises QHSYPI (SEQ ID NO: 33), and a heavy chain CDRHI region comprising the amino sequence ISYSSI (SEQ ID NO: 34), a CDRH2 region comprising the amino acid sequence SIYSYSGSTY (SEQ ID NO: 35), and a CDRH3 region comprising the amino acid sequence RYGAMD (SEQ ID NO: 36).

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
• Governing Council Univ Toronto
• Albert Einstein College Medicine Inc

Inventors

• Gavathiotis Evripidis
• Lai Jonathan R
• Sidhu Sachdev

Classifications

• G01N33/575

  for cancer · CPC title

• C07K2317/92

  Affinity (KD), association rate (Ka), dissociation rate (Kd) or EC50 value · CPC title

• C07K2317/565

  Complementarity determining region [CDR] · CPC title

• G01N2510/00

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

• A61K9/127

  Synthetic bilayered vehicles, e.g. liposomes or liposomes with cholesterol as the only non-phosphatidyl surfactant · CPC title