Serum GP73, a marker for evaluating progression in patients with chronic HBV infections

This study was designed to investigate the role of serum GP73 for diagnosing significant fibrosis in patients with chronic hepatitis B virus (HBV) infections. Two populations were enrollment. All subjects were patients with chronic HBV infections. First population included 761 patients, who received liver stiffness measurement; the second population included 633 patients, who undertaken liver biopsy, in which 472 patients with nearly normal ALT. All patients received serum GP73 test. The effect of GP73 recombinant protein to HepG2 cells and LX2 cells were observed in vitro. Results showed that serum GP73 concentration is correlated with liver stiffness (r = 0.601). The area under ROC curve is 0.76. The sensitivity and specificity of GP73 for significant fibrosis (≥F2) diagnosis were 62.81%, 80.05% respectively (cut off: 76.6 ng/ml). Serum GP73 concentration was significantly correlated with the grading of fibrosis (r = 0.32, and 0.35, in 633 and 472 patients, respectively.) GP73 had a striking performance for diagnosing S2 in patients with chronic HBV infections. In 472 patients with nearly normal ALT, the sensitivity and specificity of GP73 for S2 diagnosis were 62.5% and 80.0% respectively, where the cut-off was set at 82 ng/ml. GP73 recombinant protein may prompt LX2 cells proliferation at the concentration 10-100 ng/ml. The present results indicated that GP73 may be a marker for diagnosing significant fibrosis in patients with chronic HBV infections, and may be a new contributor to fibrogensis.