Non-recombinant human insulin-like growth factor binding protein concentrate

Patent metadata

Field	Value
Publication number	US-12167255-B2
Application number	US-202016949817-A
Country	US
Kind code	B2
Filing date	Nov 16, 2020
Priority date	Dec 31, 2015
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A human insulin-like growth factor (IGF) binding protein stock solution and method of making the same include a non-recombinant human IGF binding protein-3 (nr-IGFBP-3) in an aqueous buffered medium. The concentration of the nr-IGFBP-3 in the stock solution ranges from about 16 micrograms per milliliter (μg/ml) to about 40 μg/ml. A kit includes a set of calibrators for nr-IGFBP-3. The set of calibrators includes the nr-IGFBP-3 in different concentrations.

First claim

What is claimed is:

1. A method of forming a concentrate of a non-recombinant human insulin-like growth factor (IGF) binding protein 3 (nr-IGFBP-3) in a native heterogeneous form in aqueous solution, the method comprising:
(1) contacting a porous matrix with an aqueous solution, wherein the aqueous solution is human serum or IGF binding protein from the human serum; and
(2) collecting concentrated nr-IGFBP-3 in the native heterogeneous form in aqueous solution from the porous matrix, the collected nr-IGFBP-3 in aqueous solution having a concentration within a range of from about 16 micrograms per milliliter (μg/ml) to about 40 μg/ml; and
wherein the concentrate contains no recombinant IGFBP-3.

2. The method of claim 1 , wherein the porous matrix is one or more of an ultrafiltration disc, a filtration membrane, and a sepharose-based resin.

3. The method of claim 1 , further comprising the step of forming the aqueous solution of human serum of step (1) by mixing human serum with a first buffer solution, and wherein contacting the porous matrix with the aqueous solution comprises the steps of:
applying the human serum in the first buffer solution to a chromatography column with a sepharose-based resin equilibrated with a second buffer solution to separate nr-IGFBP-3 from other serum proteins in the human serum;
eluting the nr-IGFBP-3 from the sepharose-based resin with a third buffer solution; and
applying the eluted nr-IGFBP-3 in the third buffer solution to a filtration membrane with an exchange buffer to buffer exchange and concentrate the nr-IGFBP-3 in aqueous solution.

4. The method of claim 1 , further comprising the step of forming the aqueous solution of IGF binding protein from the human serum of step (1) comprising:
mixing the human serum with a saturated anti-chaotropic salt solution to form a mixture;
isolating the IGF binding protein from the mixture; and
reconstituting the isolated IGF binding protein in a buffer solution; and
wherein contacting the porous matrix with the aqueous solution comprises applying the reconstituted IGF binding protein in buffer solution to one or both of a filtration membrane and an ultrafiltration disc with an exchange buffer to buffer exchange and to concentrate nr-IGFBP-3 in aqueous solution.

5. The method of claim 4 , wherein the saturated anti-chaotropic salt solution comprises an anti-chaotropic sulfate salt in water.

6. The method of claim 4 , wherein the saturated anti-chaotropic salt solution comprises an ammonium sulfate salt in a sodium phosphate solution.

7. The method of claim 1 , wherein the step of contacting the porous matrix with the aqueous solution comprises tangential flow filtration with a buffer exchange solution.

8. The method of claim 1 , wherein the aqueous solution in which the nr-IGFBP-3 is disposed comprises a buffer selected from the group consisting of borate, phosphate, carbonate, Tris (Tris (hydroxymethyl) amino-methane), barbital, PIPES (piperazine-N,N-bis (2-ethanesulfonic acid)), HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), MES (2-(N-morpholino)-ethanesulfonic acid), ACES (N-(2-Acetamido)-2-aminoethanesulfonic acid), MOPS (3-(N-morpholino) propanesulfonic acid), BICINE (N,N-bis (2-hydroxyethyl)-glycine), and any combination thereof.

9. The method of claim 1 , wherein the aqueous solution has a pH in a range of from about 7.0 to about 9.0.

10. The method of claim 1 , further comprising the step of preparing a set of calibrators from the concentrated nr-IGFBP-3 solution by diluting the concentrated nr-IGFBP-3 solution to various concentrations, wherein the concentration of nr-IGFBP-3 in each calibrator is different and is within a range of from about 0.5 μg/ml to about 16 μg/ml, the set of calibrators being configured to calibrate measurement of one or both of IGFBP-3 and IGF-1 in patient samples.

11. The method of claim 10 , wherein the concentrated nr-IGFBP-3 solution is diluted with different quantities of an acid treated and charcoal absorbed human serum diluent that is substantially free of IGF binding protein.

12. The method of claim 1 , further comprising the step of preparing a set of calibrators for an IGFBP-3 analyte immunoassay from the concentrated nr-IGFBP-3 solution by diluting the concentrated nr-IGFBP-3 solution to various concentrations in a human serum diluent, wherein the concentration of nr-IGFBP-3 in each calibrator is different and is within a range of from about 16 μg/ml to about 40 μg/ml, the set of calibrators being configured to calibrate measurement of one or both of IGFBP-3 and IGF-1 in patient samples.

13. The method of claim 12 , wherein the human serum diluent is an acid treated and charcoal absorbed human serum diluent that is substantially free of IGF binding protein.

14. The method of claim 1 , wherein the concentrated nr-IGFBP-3 in native heterogeneous form comprises glycosylated nr-IGFBP-3.

15. The method of claim 1 , wherein the concentrated nr-IGFBP-3 in native heterogeneous form comprises at least one complex formed with at least one protein selected from the group consisting of insulin-like growth factor-1 (IGF-1), insulin-like growth factor-2 (IGF-2), acid-labile subunit protein (ALS), and combinations thereof.

16. The method of claim 1 , wherein the concentrated nr-IGFBP-3 in native heterogeneous form has a nominal molecular weight in a range of from about 25 kDa to about 155 kDa.

17. A kit comprising a set of calibrators produced by the method of claim 10 .

18. A kit comprising a set of calibrators produced by the method of claim 12 .

19. A human insulin-like growth factor (IGF) binding protein stock calibration solution for automated immunoassay equipment prepared by the method of claim 1 , wherein the calibration solution comprises:
a non-recombinant human IGF binding protein-3 (nr-IGFBP-3); and
an aqueous buffered medium in which the nr-IGFBP-3 is disposed, the aqueous buffered medium comprising a buffer selected from the group consisting of borate, phosphate, carbonate, Tris (Tris (hydroxymethyl)amino-methane), barbital, PIPES (piperazine-N,N-bis (2-ethanesulfonic acid)), HEPES (He-4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), MES (2-(N-morpholino)-ethanesulfonic acid), ACES (N-(2-Acetamido)-2-aminoethanesulfonic acid), MOPS (3-(N-morpholino)propanesulfonic acid), BICINE (N,N-bis (2-hydroxyethyl)-glycine), and any combination thereof, wherein the aqueous buffered medium has a pH in a range of from about 7.0 to about 9.0; and
wherein the calibration solution has an nr-IGFBP-3 concentration ranging from about 16 micrograms per milliliter (μg/ml) to about 40 μg/ml; and
wherein the calibration solution contains no recombinant IGFBP-3.

20. The human IGF binding protein stock calibration solution of claim 19 , wherein the nr-IGFBP-3 concentration is within a range of about 20 μg/ml to about 30 μg/ml, and wherein the aqueous buffered medium has a pH in a range of from about 7.25 to about 8.6.

21. The human IGF binding protein stock calibration solution of claim 19 , wherein the aqueous buffered medium comprises at least one of phosphate buffered saline (PBS), PBS plus sodium azide, and Tris.

Assignees

• Siemens Healthcare Diagnostics Inc

Inventors

• Lin Spencer
• Osae-Kwapong Kwasi
• Quraishi Omar
• Sinha Seema
• Smith Michele
• Difrancesco Sunray
• Spears Ryan
• Rawal Dharini
• Hovanec-Burns Debra
• Owens Robert

Classifications

• C07K14/435

  from animals; from humans · CPC title

• H04W72/046

  the resource being in the space domain, e.g. beams · CPC title

• H04W24/02 Primary

  Arrangements for optimising operational condition · CPC title

• H04L41/0806

  for initial configuration or provisioning, e.g. plug-and-play · CPC title

• H04B7/0617

  for beam forming · CPC title