Serum Level of SHAP as a Disease Marker: A Comparison with Hyaluronan

Abstract

Hyaluronan (HA) has been reported to be associated with the progression of various inflammatory diseases and cancer malignancy. The serum level of HA is a clinical biomarker for rheumatoid arthritis and liver cirrhosis, conditions in which elevated HA levels are due to the enhanced production in the joint synovium and impaired uptake and clearance in the hepatic sinusoidal endothelium, respectively. We have discovered that inflammation is often accompanied by the covalent modification of HA by serumderived HA-associated protein (SHAP), derived from the heavy chains of the plasma protein inter-alpha-trypsin inhibitor, which changes the biological activity of HA and participates in regulation of the inflammatory response. We compared the serum levels of SHAP and HA in a number of diseases. The results indicated that the SHAP level was more closely correlated with disease stages and with the other related biomarkers than was HA. This review summarizes these findings and concludes that SHAP is superior to HA as a disease marker.