Antibodies and assays for detection of Burkholderia mallei

Patent metadata

Field	Value
Publication number	US-12467921-B2
Application number	US-202117463109-A
Country	US
Kind code	B2
Filing date	Aug 31, 2021
Priority date	Aug 31, 2021
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

Disclosed are B5 hybridoma and a B5 monoclonal antibody to Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis and methods of use. Also disclosed are isolated binding fragments, isolated antibody fragments, isolated monoclonal antibodies, isolated chimeric antibodies, and isolated humanized antibodies having the binding fragments of the B5 monoclonal antibody. Also disclosed are assays for detecting B. mallei, B. pseudomallei , or B. thailandensis in a sample, for detecting infection by B. mallei, B. pseudomallei , or B. thailandensis , and therapeutic methods for treating infections by B. mallei, B. pseudomallei , or B. thailandensis.

First claim

We claim:

1 . An isolated antibody or antigen binding fragment thereof that binds to lipopolysaccharide (LPS) from Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis , the isolated antibody comprising:
a heavy chain variable domain (VH) comprising three heavy chain complementarity regions (CDRs), VHCDR1, VHCDR2, and VHCDR3, and a light chain variable domain (VL) comprising three light chain CDRs, VLCDR1, VLCDR2, and VLCDR3; wherein the VHCDR1, VHCDR2, and VHCDR3 are VHCDR1, VHCDR2, and VHCDR3, respectively, of monoclonal antibody B5 produced from a hybridoma deposited under ATCC Accession Deposit Number PTA-127021, and wherein the VLCDR1, VLCDR2, and VLCDR3 are VLCDR1, VLCDR2, and VLCDR3, respectively, of monoclonal antibody B5 produced from the hybridoma deposited under ATCC Accession Deposit Number PTA-127021.

2 . The isolated antibody of claim 1 , wherein the isolated antibody is an isolated monoclonal antibody.

3 . A chimeric antibody derived from the monoclonal antibody of claim 2 .

4 . A humanized antibody derived from the monoclonal antibody of claim 2 .

5 . The isolated antibody of claim 1 having a binding specificity to bacterial extract from Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis.

6 . The isolated antibody of claim 1 , having a relative binding specificity to purified lipopolysaccharide (LPS) from Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis over bovine serum albumin (BSA) at a ratio of a detection signal from binding to the Burkholderia mallei LPS, Burkholderia pseudomallei LPS, or Burkholderia thailandensis LPS to a detection signal from binding to BSA is between 2:1 and 20:1, when the concentration of purified lipopolysaccharide (LPS) from Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis is between 0.1 ng/μL and 10 ng/μL.

7 . The isolated antibody of claim 1 , having a relative binding specificity to purified LPS from Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis over bovine serum albumin (BSA) at a ratio between 5:1 and 20:1 of (i) a detection signal from binding of the binding fragment to the Burkholderia mallei LPS, Burkholderia pseudomallei LPS, or Burkholderia thailandensis LPS to (ii) a detection signal from binding of the binding fragment to BSA, when the concentration of purified lipopolysaccharide (LPS) from Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis is between 0.1 ng/μL and 10 ng/μL.

8 . The isolated antibody of claim 1 , in a composition for detecting antibodies against Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis.

9 . The isolated antibody of claim 1 , in a composition for treating a Burkholderia mallei, Burkholderia pseudomallei , or Burkholderia thailandensis infection.

10 . The isolated antibody of claim 1 , wherein the VH further comprises four framework regions VHFR1, VHFR2, VHFR3, and VHFR4, and the VL further comprises four framework regions VLFR1, VLFR2, VLFR3, and VLFR4.

11 . The isolated antibody of claim 10 , wherein the VHFR1, VHFR2, VHFR3, and VHFR4 of the isolated antibody are the same as or different from VHFR1, VHFR2, VHFR3, and VHFR4 of the monoclonal antibody B5 produced from the hybridoma deposited under ATCC Accession Deposit Number PTA-127021; and
wherein VLFR1, VLFR2, VLFR3, and VLFR4 of the isolated antibody are the same as or different from VHFR1, VHFR2, VHFR3, and VHFR4 of the monoclonal antibody B5 produced from the hybridoma deposited under ATCC Accession Deposit Number PTA-127021.

12 . A kit comprising the antibody of claim 1 , and optionally, an antigen.

13 . The kit of claim 12 , wherein the antigen is a purified B. mallei lipopolysaccharide (“LPS”).

14 . A test kit for detecting the presence, absence, and/or the concentration of Burkholderia mallei (“ B. mallei ”) antibodies in a test sample, the kit comprising an antigen and the isolated antibody or antigen binding fragment of claim 1 .

15 . The test kit of claim 14 , wherein each of the antigen and the isolated antibody or antigen binding fragment is in the form of a solid or a liquid.

16 . The test kit of claim 14 further comprising a solid support, wherein the antigen is in the form of a solid immobilized on a surface of the solid support.

17 . The test kit of claim 16 , wherein the solid support is a plate comprising a plurality of microtiter wells, wherein the antigen is immobilized on a bottom surface of at least a portion of the wells.

18 . The test kit of claim 16 , wherein the solid support further comprises an inlet and a first channel or a first set of channels,
wherein the first channel or first set of channels is configured to allow a solution to flow from the inlet to the reaction region.

19 . The test kit of claim 18 , wherein the solid support further comprises a second channel or a second set of channels and an outlet,
wherein the second channel or second set of channels is configured to allow the solution to flow from the reaction region to the outlet.

20 . The test kit of claim 14 further comprising one or more reagents selected from the group consisting of a second antibody-detection label conjugate, an enzyme substrate, and a stop solution, and combinations thereof.

21 . The test kit of claim 20 , wherein each reagent, each buffer, or each of the reagent and buffer is provided in the form of a solid or a liquid.

22 . The test kit of claim 20 , wherein the second antibody-detection label conjugate is a conjugate of a horse radish peroxidase (HRP) enzyme and the enzyme substrate is tetramethylbenzidine (“TMB”).

23 . The test kit of claim 14 further comprising one or more buffer solutions selected from the group consisting of a blocking buffer, a sample dilution buffer, an enzyme dilution buffer, a wash buffer, and combinations thereof.

24 . The test kit of claim 14 further comprising a control sample.

25 . The test kit of claim 14 further comprising an instruction for use.

26 . The test kit of claim 14 , wherein the antigen is purified B. mallei LPS, and optionally, wherein the B. mallei LPS is purified from B. mallei strain MB1731.

27 . A competitive enzyme-linked immunosorbent assay (“cELISA”) kit for detecting the presence, absence, and/or the concentration of B. mallei antibodies in a biological sample comprising
a plate comprising a plurality of microtiter wells;
a purified B. mallei LPS; and
the isolated antibody or antigen binding fragment of claim 1 ,
wherein each of the purified B. mallei LPS and the isolated antibody or antigen binding fragment is in the form of a solid or a liquid.

28 . The cELISA kit of claim 27 further comprising one or more reagents selected from the group consisting of a second antibody-detection label conjugate, an enzyme substrate, a stop solution, and combinations thereof.

29 . The cELISA kit of claim 28 , wherein each reagent, each buffer, or each of the reagent and buffer is provided as a solid or a liquid.

30 . The cELISA kit of claim 28 , wherein the second antibody-detection label conjugate is a conjugate of a horse radish peroxidase (HRP) enzyme and the enzyme substrate is TMB.

Assignees

• Versitech Ltd
• Central Veterinary Res Laboratory

Inventors

• Teng Lee Lee
• Woo Patrick Chiu Yat
• Chan Elaine
• Lau Susanna Kar Pui
• Yeung Man Lung
• Wernery Ulrich

Classifications

• G01N2469/20

  Detection of antibodies in sample from host which are directed against antigens from microorganisms · CPC title

• C07K2317/565

  Complementarity determining region [CDR] · CPC title

• C07K2317/567

  Framework region [FR] · CPC title

• C07K2317/24

  containing regions, domains or residues from different species, e.g. chimeric, humanized or veneered · CPC title

• G01N2400/50

  Lipopolysaccharides; LPS · CPC title