ArticleFrontiers in immunology2013
Endogenous Acute Phase Serum Amyloid A Lacks Pro-Inflammatory Activity, Contrasting the Two Recombinant Variants That Activate Human Neutrophils through Different Receptors.
Article in Frontiers in immunology, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 36 papers.
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Who cites it
36 citing papers in PubMed, 57 citations in OpenAlex.
- Serum amyloid A: multifaceted roles in inflammation and cellular interactions.Immunologic research · 2025Review
- Recent Advances in Studies of Serum Amyloid A: Implications in Inflammation, Immunity and Tumor Metastasis.International journal of molecular sciences · 2025Review
- Interactions of Serum Amyloid A Proteins with the Blood-Brain Barrier: Implications for Central Nervous System Disease.International journal of molecular sciences · 2024Review
- Effects of Ozone on Sickness and Depressive-like Behavioral and Biochemical Phenotypes and Their Regulation by Serum Amyloid A in Mice.International journal of molecular sciences · 2023Article
- Acute-serum amyloid A and A-SAA-derived peptides as formyl peptide receptor (FPR) 2 ligands.Frontiers in endocrinology · 2023Review
- Article
- Maternal siRNA silencing of placental SAA2 mitigates preterm birth following intrauterine inflammation.Frontiers in immunology · 2022Article
- Association of Serum Interleukin-8 and Serum Amyloid A With Anxiety Symptoms in Patients With Cerebral Small Vessel Disease.Frontiers in neurology · 2022Article
- Immunological response of human leucocytes after exposure to lipopolysaccharides from Porphyromonas gingivalis.Clinical and experimental dental research · 2021Article
- Effects of serum amyloid protein A on influenza A virus replication and viral interactions with neutrophils.Journal of leukocyte biology · 2021Article
- Review
- A Cross-Sectional and Longitudinal Study to Define Alarmins and A-SAA Variants as Companion Markers in Early Rheumatoid Arthritis.Frontiers in immunology · 2021Article
- Serum Amyloid A1 Induces Classically Activated Macrophages: A Role for Enhanced Fibril Formation.Frontiers in immunology · 2021Article
- Current Understanding of the Relationship of HDL Composition, Structure and Function to Their Cardioprotective Properties in Chronic Kidney Disease.Biomolecules · 2020Review
- Serum amyloid A is a soluble pattern recognition receptor that drives type 2 immunity.Nature immunology · 2020Article
- Machine learning application for development of a data-driven predictive model able to investigate quality of life scores in a rare disease.Orphanet journal of rare diseases · 2020Article
- Serum Amyloid A1 (SAA1) Revisited: Restricted Leukocyte-Activating Properties of Homogeneous SAA1.Frontiers in immunology · 2020Article
- Biological Characterization of Commercial Recombinantly Expressed Immunomodulating Proteins Contaminated with Bacterial Products in the Year 2020: The SAA3 Case.Mediators of inflammation · 2020Article
- Role of serum amyloid A in atherosclerosis.Current opinion in lipidology · 2019Review
- Intestinal Serum amyloid A suppresses systemic neutrophil activation and bactericidal activity in response to microbiota colonization.PLoS pathogens · 2019Article
Corrections and comments
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Authors and funding
7 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Most notable among the acute phase proteins is serum amyloid A (SAA), levels of which can increase 1000-fold during infections, aseptic inflammation, and/or trauma. Chronically elevated SAA levels are associated with a wide variety of pathological conditions, including obesity and rheumatic diseases. Using a recombinant hybrid of the two human SAA isoforms (SAA1 and 2) that does not exist in vivo, numerous in vitro studies have given rise to the notion that acute phase SAA is a pro-inflammatory molecule with cytokine-like properties. It is however unclear whether endogenous acute phase SAA per se mediates pro-inflammatory effects. We tested this in samples from patients with inflammatory arthritis and in a transgenic mouse model that expresses human SAA1. Endogenous human SAA did not drive production of pro-inflammatory IL-8/KC in either of these settings. Human neutrophils derived from arthritis patients displayed no signs of activation, despite being exposed to severely elevated SAA levels in circulation, and SAA-rich sera also failed to activate cells in vitro. In contrast, two recombinant SAA variants (the hybrid SAA and SAA1) both activated human neutrophils, inducing L-selectin shedding, production of reactive oxygen species, and production of IL-8. The hybrid SAA was approximately 100-fold more potent than recombinant SAA1. Recombinant hybrid SAA and SAA1 activated neutrophils through different receptors, with recombinant SAA1 being a ligand for formyl peptide receptor 2 (FPR2). We conclude that even though recombinant SAAs can be valuable tools for studying neutrophil activation, they do not reflect the nature of the endogenous protein.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.