Methods of detecting a fragment of neurosecretory protein VGF for diagnosing alzheimer's disease
The present invention provides a neurosecretory protein VGF peptide useful in qualifying Alzheimer's disease status in a patient. In particular, this peptide and modified forms thereof may be used to classify a subject sample as Alzheimer's disease or non-Alzheimer's disease. The peptide biomarker can be detected by SELDI mass spectrometry.
1. A method for qualifying Alzheimer's disease status in a subject comprising:
(a) measuring the concentration of a VGF peptide-1 consisting of the amino acid sequence of SEQ ID NO:1 in cerebral spinal fluid (CSF) from the subject; and
(b) correlating the the concentration of the VGF peptide-1 with Alzheimer's disease status, wherein an increased CSF concentration of the VGF peptide-1 is indicative of Alzheimer's disease.
2. The method of claim 1 , wherein the VGF peptide-1 is measured by capturing the VGF peptide-1 on an adsorbent surface of a SELDI probe and detecting the captured VGF peptide-1 by laser desorption-ionization mass spectrometry.
3. The method of claim 2 , wherein the adsorbent is an anion-exchange adsorbent.
4. The method of claim 2 , wherein the adsorbent is a biospecific adsorbent.
5. The method of claim 1 , wherein VGF peptide-1 is measured by a method that does not involve measuring the mass of VGF peptide-1.
6. The method of claim 5 , wherein the method involves an immunoassay.
7. The method of claim 1 , wherein the correlating is performed by a software classification algorithm.
8. The method of claim 1 , wherein Alzheimer's disease status is selected from Alzheimer's disease and non-Alzheimer's disease.
9. The method of claim 1 , further comprising: (c) reporting the status to the subject.
10. The method of claim 1 , further comprising: (c) recording the status on a tangible medium.
11. The method of claim 1 , further comprising: (c) managing subject treatment based on the status.
12. The method of claim 11 , further comprising: (d) measuring VGF peptide-1 after subject management and correlating the measurement with disease progression.
13. The method of claim 11 , wherein, the measurement correlates with Alzheimer's disease, and the managing subject treatment comprises administering a cholinesterase inhibitor to the subject.
14. The method of claim 1 , further comprising: (c) measuring the VGF peptide-1 after subject management and correlating the measurement with disease progression.
15. A method for determining the course of Alzheimer's disease comprising:
(a) measuring the CSF concentration of a VGF peptide-1 consisting of the amino acid sequence of SEQ ID NO: 1 in a subject sample at a first time;
(b) measuring the CSF concentration of the VGF peptide-1 in a subject sample at a second time; and
(c) comparing the first measurement and the second measurement; wherein an increased CSF concentration of the VGF peptide-1 in the second measurement indicates progression of Alzheimer's disease.