Biological actions of pentraxins.

Abstract

The innate immunity is the first defense reaction against microorganisms or altered self-components upon tissue injury. Such exogenous or modified endogenous molecules present conserved molecular structures that are recognized by the immune system via pattern-recognition receptors or molecules. Within the soluble pattern-recognition molecules pentraxins play an important role in humoral innate immunity. Pentraxins branch off into the short and long pentraxins. Short constituents include C-reactive protein (CRP) and serum amyloid P-component which are synthesized in the liver mostly upon IL-6 stimulation. Long constituent pentraxin3 (PTX3) is produced by several immune and vascular cells in response to pro-inflammatory signals (but not IL-6) and by toll-like receptor engagement. The ability of pentraxins to interact with numerous ligands (microorganisms, the complement system, dead cells, modified plasma proteins, cellular receptors, extracellular matrix components, and growth factors) supports their involvement in multiple biological functions. As such, the capability of CRP and PTX3 to modulate inflammation through the complement system and innate immunity suggests their contribution in atherosclerosis, thrombosis, and ischemic heart disease. In this review we will overview the key properties of pentraxins and discuss the major relevant findings that attribute to pentraxins, particularly CRP and PTX3, a biological role in the pathogenesis of cardiovascular disease.