Aβ Peptide | predicted MW | observed MW | AD (n= 16) | PA (n= 9) | NDC (n= 8) |
|---|
8-40 | 3458.98 | 3462.81 |
1 (6.3%)
| | |
4-40
|
4014.57
|
4018.49
|
1 (6.3%)
| | |
4-42 | 4198.74 | 4202.62 | 4 (25.0%) | 3 (33.39%) | 1 (12.5%) |
1-40 | 4329.78 | 4333.49 | 3 (18.8%) | | 1 (12.5%) |
1-42 | 4514.02 | 4516.74 | 9 (56.3%) | 7 (77.80%) | 2 (25%) |
1-42 +16 Da | 4530.02 | 4534.90 | 2 (12.5%) | 2 (22.2%) | 2 (25%) |
- Human brain tissue was extracted with 2% SDS and sequentially immunoprecipitated with Ab9 and 4G8 antibodies to enrich different truncated or modified Aβ peptides. Mass spectrometric analysis shows unique Aβ peptides that 1) have not been previously reported in other mass spectrometric analyses of AD brains (underlined) 2) uniquely present in AD (bold font) are differentially highlighted. Predicted molecular weights and observed molecular weights have been calculated using ExPASy PeptideMass and ProteinChip Data Manager software (Bio-Rad), respectively. The number of subjects (AD, Alzheimer's disease; PA, Pathological aging; NDC, controls) displaying each uniquely identifiable Aβ peptide and the percentage of occurrence of such peptides corresponding to the total sample size is denoted. Aβ, amyloid β; MW, molecular weight; n, number; SDS, sodium dodecyl sulfate.
