Home › Research › Risk genes beyond APOE
Platelet coagulation factor XIa-inhibitor, a form of Alzheimer amyloid precursor protein
Smith RP, Higuchi DA, Broze GJ.. Science (New York, N.Y.), 1990-06-01
Topic: Amyloid, tau and blood-test diagnosis
Plain-language summary
An inhibitor of coagulation factor XIa was purified from serum-free conditioned medium of HepG2 liver cells. Platelets stimulated with thrombin or calcium ionophore (A23187) secrete a protein functionally and immunologically identical to the inhibitor, implying a role for this inhibitor in hemostasis. Analysis of the amino-terminal amino acid sequence and immunologic reactivity showed the inhibitor to be a truncated form of the Alzheimer's amyloid precursor protein that contains a Kunitz-type serine protease inhibitor domain and at least a portion of the amyloid beta protein.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
Smith, R. P., Higuchi, D. A., & Broze, G. J. (1990). Platelet coagulation factor XIa-inhibitor, a form of Alzheimer amyloid precursor protein. Science (New York, N.Y.). https://doi.org/10.1126/science.2111585
Vancouver
Smith RP, Higuchi DA, Broze GJ. Platelet coagulation factor XIa-inhibitor, a form of Alzheimer amyloid precursor protein. Science (New York, N.Y.). 1990. doi:10.1126/science.2111585. PMID: 2111585.
BibTeX
@article{smith1990-2111585,
author = {Smith, R. P. and Higuchi, D. A. and Broze, G. J.},
title = {{Platelet coagulation factor XIa-inhibitor, a form of Alzheimer amyloid precursor protein}},
journal = {Science (New York, N.Y.)},
year = {1990},
doi = {10.1126/science.2111585},
pmid = {2111585},
url = {https://doi.org/10.1126/science.2111585}
}
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
Key findings
- Platelets stimulated with thrombin or calcium ionophore (A23187) secrete a protein functionally and immunologically identical to the inhibitor, implying a role for this inhibitor in hemostasis.
- Analysis of the amino-terminal amino acid sequence and immunologic reactivity showed the inhibitor to be a truncated form of the Alzheimer's amyloid precursor protein that contains a Kunitz-type serine protease inhibitor domain and at least a portion of the amyloid beta protein.
- It inhibits factor XIa and trypsin with a Ki of 450 +/- 50 pM and 20 +/- 10 pM, respectively.
- Heparin (1 unit/ml) did not significantly effect inhibition of trypsin, but inhibition of XIa was 15 times greater (Ki = 25 +/- 15 pM) in the presence of heparin.
Why it matters
A clotting-factor inhibitor purified from cultured liver cells, and also released by stimulated platelets, turned out to be a shortened form of the Alzheimer's amyloid precursor protein. It contains a protease-inhibitor (Kunitz-type) region and at least part of amyloid beta, and in lab tests heparin made it block factor XIa about 15 times more strongly. This links the protein behind Alzheimer's amyloid to blood clotting. It is lab protein chemistry, not a study of patients, and says nothing about treating or preventing Alzheimer's.
New to this subject? Start with our plain-English guide: Genetics →
Study details
- Evidence strengthLow
How this study scored 48/100
Published in a top-tier journal. Scored zero for study design, sample size, effect reported, studied in people and randomized / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 10 / 10 | Tier 1 — top-tier general journal (Science (New York, N.Y.)) |
| Journal's citation record | 4 / 4 | Science: journal h-index 1,754 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1990 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomized / blinded | 0 / 2 | No randomization or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 6 / 7 | Cited 303 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 8.0 citations a year over 38 year(s) since 1990 |
| Impact for its field and year | 5 / 6 | Cited 24.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 12 other studies in this library |
| Still being cited | 1 / 4 | Cited 7 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author George Broze: h-index 58 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | Washington University Medical Center: institution h-index 348 (OpenAlex) |
| Multicenter collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 2111585) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 48 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
May need a subscription OpenAlex found no free copy of the full text (checked 6 Feb 1020), so the publisher may charge for it. The PubMed abstract is free.
Related
Studies in the library that share something with this one. The line above each title says what.
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.
Later studies that cite this one
12 studies in the alzhub library list this one in their references. Showing the 8 highest-scoring.
Related studies in Risk genes beyond APOE from nearby years
Also tagged “precursor”
1,337 studies in the library carry the topic tag “precursor”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 1,337 tagged studies.