
Health Dictionary
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Acute phase reactant
Introduction

Overview
Overview
Acute-phase proteins are a class of proteins whose plasma concentrations increase (positive acute phase proteins) or decrease (negative acute phase proteins) in response to inflammation. This response is called the acute-phase reaction (also called acute phase response).
In response to injury, local inflammatory cells (neutrophil granulocytes and macrophages) secrete a number of cytokines into the bloodstream, most notable of which are the interleukins IL-1, IL-6 and IL-8, and TNF-α.
The liver responds by producing a large number of acute-phase reactants.
Examples
Examples
The notable are:
- D-dimer protein
- C-reactive protein
- Mannose-binding protein
- Alpha 1-antitrypsin
- Alpha 1-antichymotrypsin
- Alpha 2-macroglobulin
- some coagulation factors (Fibrinogen, prothrombin, factor VIII, von Willebrand factor, plasminogen)
- Complement factors
- Ferritin
- Serum amyloid P component (see amyloid)
- Serum amyloid A
- Prealbumin
Serum albumin concentrations fall in acute disease states. For this reason albumin is sometimes referred to as a negative acute phase protein.
Clinical significance
Clinical significance
Measurement of acute phase proteins is a useful marker of inflammation in both medical and veterinary clinical pathology. It correlates with the erythrocyte sedimentation rate (ESR).
External links
External links
- Acute-Phase+Proteins at the US National Library of Medicine Medical Subject Headings (MeSH)
de:Akute-Phase-Protein nl:Acutefase-eiwit sl:Beljakovina akutne faze sv:Akutfasprotein
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
