Testican-1, as a novel diagnosis of sepsis.

The development of new sepsis-specific biomarkers is mandatory to improve the detection and monitoring of the disease. Testican-1 is a highly conserved, multidomain proteoglycan that is most prominently expressed in the thalamus of the brain, and is upregulated in activated astroglial cells of the cerebrum. The aim of this study was to evaluate blood levels of Testican-1 in septic patients. A prospective study of 82 patients with sepsis was conducted. Furthermore, C57BL/6 mice were administrated with lipopolysaccharide (LPS), high mobility group box 1 (HMGB1) protein or subjected to cecal ligation and puncture (CLP) surgery. Alternatively, human umbilical vein endothelial cells (HUVECs) or C57BL/6 mice were exposed to LPS (100 ng/mL) or HMGB1 (1 μg/mL). LPS, HMGB1, or CLP enhanced the synthesis and secretion of Testican-1 in HUVECs and mice. In patients admitted to the intensive care unit (ICU) with sepsis, circulating levels of Testican-1 were significantly high (sepsis, 20.44-63.37 ng/mL, n = 30; severe sepsis, 41.30-98.69 ng/mL, n = 22; septic shock, 98.10-151.85 ng/mL, n = 30) when compared to the levels of control donors (6.97-8.77 ng/mL, n = 21), reflecting the severity of the disease. These results suggest that in septic patients, Testican-1 blood level is related to the severity of sepsis and Testican-1 could be used as a biomarker to determine the severity of sepsis.