protein
Serum amyloid P-component
aka SAP
Gene
APCS
Organism
Homo sapiens(9606)
Length
223 aa
Mass
25,387 Da
Serum amyloid P-component (SAP), encoded by APCS, is a 223-amino acid protein that functions as a calcium-dependent lectin and can interact with DNA and histones (UniProt: P02743). It may scavenge nuclear material released from damaged circulating cells, suggesting roles in cellular debris clearance and immune regulation.
SAP is a circulating acute-phase reactant traditionally associated with inflammation and tissue damage response. While UniProt lists no specific disease annotations for this protein, it has broader relevance to neuroinflammatory processes given its capacity to bind nuclear antigens and participate in immune clearance pathways.
In Alzheimer's disease, SAP is upregulated in post-mortem AD brain tissue relative to age-matched controls (Chaparral AD proteomics). Quantitative proteomics analysis detected SAP at a mean log2 fold-change of +1.57 in human brain from AD patients versus controls, measured via TMT-labeled mass spectrometry across four subcellular fractions. This elevation suggests potential involvement in AD-associated neuroinflammation or amyloid-related pathology.
Generated from the curated entity record below. May contain errors — verify against source links.
Proteomics Evidence · AD
↑ Up in ADP3
not detected
P2
not detected
S2
+1.570
S3
not detected
Mean log₂FC across detected fractions: +1.57 (1 of 4 fractions detected)
Human post-mortem AD brain vs age-matched controls, TMT-labeled, 4 subcellular fractions (P2, P3, S2, S3), DDA proteomics.
Related Publications
Browse all →Tau molecular diversity contributes to clinical heterogeneity in Alzheimer's disease.
Dujardin Simon et al.Nature medicine2020PMID 32572268Deep Multilayer Brain Proteomics Identifies Molecular Networks in Alzheimer's Disease Progression.
Bai Bing et al.Neuron2020PMID 31926610A Multi-network Approach Identifies Protein-Specific Co-expression in Asymptomatic and Symptomatic Alzheimer's Disease.
Seyfried Nicholas T et al.Cell systems2017PMID 27989508Large-scale deep multi-layer analysis of Alzheimer's disease brain reveals strong proteomic disease-related changes not observed at the RNA level.
Johnson Erik C B et al.Nature neuroscience2022PMID 35115731Organization and regulation of gene transcription.
Cramer PatrickNature2019PMID 31462772
Function
Can interact with DNA and histones and may scavenge nuclear material released from damaged circulating cells. May also function as a calcium-dependent lectin
Sources
Last updated 5/8/2026, 6:31:47 AM