Method of detecting an APP Alzheimer's disease marker peptide in patients with Alzheimer's disease
Certain embodiments are directed to marker peptides or marker peptide antibodies can be used in producing diagnostic kits or used in diagnostic methods for Alzheimer's disease. The antibodies and/or marker peptides can be used in immunohistochemical and biochemical methods for qualitative and quantitative analysis of marker peptide levels and/or localization in brain samples and CSF samples.
1. A method of detecting the presence of an APP (Amyloid Precursor Protein) Alzheimer's disease marker peptide in a patient with Alzheimer's disease, the method comprising: (a) obtaining a biological sample from a human subject with Alzheimer's disease; (b) isolating proteins from the biological sample; and (c) contacting the isolated proteins with a polyclonal antibody raised against an amino acid sequence consisting of the amino acid sequence of SEQ ID NO:18; and (d) identifying the APP Alzheimer's disease marker peptide as consisting of the amino acids: GLTTRPGSGLTNIKTEEISEVKMDAEFRHDSGYEVHHQKLVFFAEDV GSNKGAIIGLMVGGVVIATVIVITLVMLKKKQYT SIHHGVVEVDAAVTPE ERHLSKMQQNGYENPTYKFFEQMQN (SEQ ID NO:4) by mass spectrometry.
2. The method of claim 1 , wherein isolating the proteins from the biological sample comprises size fractionating the proteins from the biological sample.
3. The method of claim 2 , further comprising immunoprecipitating the biological sample with the polyclonal antibody prior to size fraction or detection.
4. The method of claim 2 , wherein protein fractionation is by size exclusion chromatography or gel electrophoresis.
5. The method of claim 4 , wherein protein fractionation is by denaturing polyacrylamide gel electrophoresis.
6. The method of claim 1 , wherein the biological sample comprises plasma, cerebrospinal fluid (CSF), brain tissue, neuronal tissue, or muscle tissue.
7. The method of claim 1 , wherein the polyclonal antibody comprises a detectable agent or label.
8. The method of claim 7 , wherein the detectable agent is a radioactive marker, a fluorescent label, or an enzymatic label.