Diagnostic assay for alzheimer's disease: assessment of ab abnormalities
AssigneeThe General Hospital Corporation
InventorsRUDOLPH E. TANZI, ASHLEY I. BUSH, ROBERT D. MOIR
Life of this patent
Estimating the term…
Abstract
The disclosed invention relates to assays for detecting and quantifying Aβ peptide, using solid supports that are coated with heavy metal cations, such as zinc (II) or copper (II) form of a nitriloacetic acid. Further, diagnostic kits are described which are used to carry out the assays of the present invention. An improvement in an assay for detection of Aβ peptide is suggested which comprises forming a heavy metal cation/solid support complex. The preferred heavy metal cations for this improvement are zinc (II) or copper (II) form of a nitriloacetic acid. Finally, methods and kits for bulk purification of Aβ peptides from biological fluids are taught.
Claims34
A diagnostic assay for detecting and/or quantifying Aβ peptide which may be present in a candidate solution, comprising:
- (a) contacting the candidate solution with a solid support with a heavy metal cation immobilized thereon to capture Aβ peptide on the surface of the solid support, thereby forming a first complex which comprises solid support/heavy metal cation/Aβ peptide;
- (b) blocking all exposed metal binding sites remaining after Aβ capture with a blocker;
- (c) contacting the first complex, which has been passed through step (b), with an antibody specific for Aβ peptide to form a second complex which comprises solid support/heavy metal cation/β peptide/antibody specific for Aβ peptide;
- (d) labelling the second complex to form a detectable third complex which comprises solid support/heavy metal cation/Aβ peptide/antibody specific for Aβ peptide/label;
- and
- (e) detecting the third complex, and quantifying Aβ peptide which may be present in the candidate solution.
A diagnostic assay for detecting and/or quantifying Aβ peptide which may be present in a candidate solution, comprising:
- (a) contacting the candidate solution with a solid support with a heavy metal cation immobilized thereon to capture Aβ peptide on the surface of the solid support, thereby forming a first complex which comprises solid support/heavy metal cation/Aβ peptide;
- (b) blocking all exposed metal binding sites remaining after Aβ capture with a blocker;
- (c) contacting the first complex, which has been passed through step (b), with an antibody specific for Aβ peptide, called Aβ antibody, to form a second complex which comprises solid support/heavy metal cation/Aβ peptide/Aβ antibody;
- (d) contacting said second complex with one or more anti-antibodies specific to the Aβ antibody to form a third complex which comprises solid support/heavy metal cation/Aβ peptide/Aβ antibody/one or more anti-antibodies;
- (e) labelling said third complex to form a detectable fourth complex which comprises solid support/heavy metal cation/Aβ peptide/Aβ antibody/one or more anti-antibodies/label;
- and
- (f) detecting the fourth complex, thereby quantifying Aβ peptide which may be present in the candidate solution.
A method for purification of Aβ peptide from biological fluids which comprises:
- (a) methylating cysteine groups of peptides in the biological fluid;
- (b) acidifying the biological fluid obtained from step (a);
- (c) applying the biological fluid obtained from step (a) to a copper-charged chelating-Sepharose column;
- (d) washing the column with equilibration buffer to obtain an eluate solution;
- and
- (e) collecting the eluate solution, thereby obtaining purified Aβ peptide.
A method for purification of Aβ peptide from biological fluids which comprises:
- (a) methylating cysteine groups of proteins in the biological fluid;
- (b) acidifying the biological fluid obtained from step (a);
- (c) adding to the biological fluid obtained from step (b), a free copper-charged chelating slurry to form a mixture;
- (d) centrifuging the mixture obtained from step (c) to obtain a pellet;
- (e) washing the pellet obtained from step (d) with equilibration buffer, thereby obtaining purified Aβ peptide.
Dependencies are inferred from the claim text.