Volume 2013 (2013), Article ID 379040, 22 pages
Pentraxins: Structure, Function, and Role in Inflammation
1The Department of Veterans Affairs Medical Center, Research Service 151, 1501 San Pedro SE, Albuquerque, NM 87108, USA
2Department of Internal Medicine, The University of New Mexico School of Medicine, Albuquerque, NM 87108, USA
Received 30 July 2013; Accepted 19 August 2013
Academic Editors: S. Brugaletta, T. Pessi, and M. Rattazzi
Copyright © 2013 Terry W. Du Clos. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The pentraxins are an ancient family of proteins with a unique architecture found as far back in evolution as the Horseshoe crab. In humans the two members of this family are C-reactive protein and serum amyloid P. Pentraxins are defined by their sequence homology, their pentameric structure and their calcium-dependent binding to their ligands. Pentraxins function as soluble pattern recognition molecules and one of the earliest and most important roles for these proteins is host defense primarily against pathogenic bacteria. They function as opsonins for pathogens through activation of the complement pathway and through binding to Fc gamma receptors. Pentraxins also recognize membrane phospholipids and nuclear components exposed on or released by damaged cells. CRP has a specific interaction with small nuclear ribonucleoproteins whereas SAP is a major recognition molecule for DNA, two nuclear autoantigens. Studies in autoimmune and inflammatory disease models suggest that pentraxins interact with macrophage Fc receptors to regulate the inflammatory response. Because CRP is a strong acute phase reactant it is widely used as a marker of inflammation and infection.