Bioprobes for lysyl oxidases and uses thereof
The present invention relates to novel bioprobes which are capable of binding to certain amine oxidase enzymes. These bioprobes are useful in methods of detecting and determining the concentration of certain amine oxidase enzymes in a sample as well as in methods for the quantitative assessment of inhibition of certain amine oxidases.
1 . A bioprobe of formula W-L-Z, wherein W represents an affinity tag; L represents a linker; and Z represents a moiety that binds to a protein selected from the group consisting of LOX, LOXL1, LOXL2, LOXL3 and LOXL4 protein, wherein Z is a moiety of Formula Ib:
wherein:
R 1a is selected from the group consisting of hydrogen, C 1-6 alkyl, —O—C 1-6 alkyl and —C(O)NR 2 R 3 or represents an attachment point for L; and
R 2 and R 3 are independently selected from the group consisting of hydrogen and C 1-6 alkyl.
2 . A method for determining a measure of the concentration of a protein selected from a lysyl oxidase (LOX) protein and a lysyl oxidase-like (LOXL) protein in a sample containing or suspected of containing the protein, comprising:
(a) obtaining a sample containing or suspected of containing the protein from a subject;
(b) contacting the sample with:
(i) a capture antibody specific for the protein under conditions sufficient to form a protein/capture antibody complex; and
(ii) the bioprobe of claim 1 ; and
(c) performing an immunoassay to measure the total concentration of the protein in the sample, wherein the immunoassay is a digital ELISA.
3 . The method of claim 2 , wherein the bioprobe is selected from the group consisting of:
4 . A method for determining the extent of enzyme inhibition of a protein selected from a lysyl oxidase (LOX) protein and a lysyl oxidase-like (LOXL) protein by a LOX or LOXL inhibitor, the method comprising:
(a) obtaining a sample containing or suspected of containing the protein from a subject;
(b) contacting the sample with a first amount of the LOX or LOXL inhibitor;
(c) contacting the sample with:
(i) a capture antibody specific for the protein under conditions sufficient to form a protein/capture antibody complex; and
(ii) a bioprobe of claim 1 ; and
(d) performing an immunoassay to measure the concentration of the protein with an enzymatic pocket occupied by the bioprobe, wherein the immunoassay is a digital ELISA.
5 . The method according to claim 4 , further comprising determining the measure of the concentration of the protein in the sample from step (a) according to a method comprising:
contacting the sample with:
(i) a capture antibody specific for the protein under conditions sufficient to form a protein/capture antibody complex; and
(ii) the bioprobe of claim 1 ; and
performing an immunoassay to measure the total concentration of the protein in the sample, wherein the immunoassay is a digital ELISA.
6 . The method according to claim 4 , further comprising determining the measure of the concentration of the protein in the sample from step (a) or (b) by:
(e) contacting the sample with a capture antibody specific for the protein under conditions sufficient to form a protein/capture antibody complex; and
(f) adding a detection antibody specific for the protein to the sample, then performing a second immunoassay to measure the total concentration of the protein in the sample, wherein the second immunoassay is a digital ELISA.
7 . The method according to claim 4 ,
wherein the binding of the LOX or LOXL inhibitor to the enzymatic pocket of the protein does not interfere with the immunoassay to measure the concentration of the protein; or
wherein the binding of the capture antibody to the protein does not interfere with the binding of the bioprobe to the enzymatic pocket of the protein; or
wherein the binding of the capture antibody to the protein does not interfere with the binding of the LOX or LOXL inhibitor to the enzymatic pocket of the protein.
8 . The method according to claim 4 , wherein the LOX or LOXL inhibitor is administered to a subject, the method comprising replacing step (a) and (b) with steps:
(a1) administering a first amount of the LOX or LOXL inhibitor to the subject; and
(b1) obtaining a sample containing or suspected of containing the protein from the subject after a predetermined period of time.
9 . The method according to claim 8 , wherein the method further comprises measuring the concentration of the protein in a sample obtained from the subject prior to administration of the LOX or LOXL inhibitor.
10 . The method according to claim 2 , further comprising:
(d) comparing the measured total concentration of the protein in the sample to a standard level; and
(e) identifying patients likely to benefit from treatment with a LOX or LOXL inhibitor.
11 . The method according to claim 2 , further comprising:
(d) comparing the measured total concentration of the protein in the sample to a standard level, wherein a difference in the concentration of the protein present in the sample compared to the standard level is indicative of the subject having a condition associated with the protein; and
wherein the condition associated with the protein is selected from the group consisting of a liver disorder, a kidney disorder, a lung disorder, fibrosis, cancer and angiogenesis.
12 . The method according to claim 2 , wherein the sample is a bodily fluid or a tissue sample.
13 . The method according to claim 12 , wherein the bodily fluid is blood or a blood component.
14 . The method according to claim 2 , wherein the volume of the sample is less than 1 mL.
15 . The method according to claim 2 , wherein the protein concentration is measured at a picomolar concentration.
16 . The method according to claim 2 , wherein the LOXL protein is a LOXL2 protein.
17 . The method according to claim 2 , wherein the capture antibody is AF2639 and the detection antibody is Fitzgerald 70R-12876.
18 . The method according to claim 2 , wherein the protein is LOX.
19 . The method according to claim 2 , wherein the capture antibody is L4794 and the detection antibody is ab219369.
20 . The method according to claim 2 , wherein the affinity tag is biotin.
21 . A kit for determining a measure of the concentration of a protein selected from a lysyl oxidase (LOX) protein and a lysyl oxidase-like (LOXL) protein in a sample, the kit comprising
a capture antibody specific for the protein, and
the bioprobe of claim 1 .
22 . A kit for determining the extent of enzyme inhibition of a protein selected from a lysyl oxidase (LOX) protein and a lysyl oxidase-like (LOXL) protein by a LOX or LOXL inhibitor, the kit comprising:
a capture antibody specific for the protein,
the bioprobe of claim 1 , and
a detection antibody specific for the protein.