Calprotectin: two sides of the same coin

Abstract

Calprotectin is a calcium binding protein produced by neutrophils and monocytes in course of inflammation. Today, the role of faecal calprotectin in chronic inflammatory bowel disease is well known, but in recent years the attention has been shifted towards circulating calprotectin. In fact, this molecule can be measured in different biological fluids: blood, saliva and urine using different analytic methods that this review describes. Furthermore, different data confirm the relevant role of serum calprotectin in autoimmune diseases. In this review we will highlight the correlation between high levels of circulating calprotectin and specific autoantibodies of major autoimmune pathologies paving the way to the employment of calprotectin measurement as useful biomarker for monitoring outcome in different pathologies.