ScussionThe ultimate aim of fibrosis grading is provided clinicians with accurate information for treatment decision and prognosis judgment. Identifying significant fibrosis is also one of critical factors for treatment decision, especially for patients with mild abnormal ALT [18]. Avoided or reduced times of liver biopsy, but obtained pathological information from liver tissue, is always pursued by clinicians. Multi-marker combination can provide more accurate information about fibrosis [19], but result in 4 IBP site increasing the patient’s expenditure and clinician’s working load. Based on our present data, GP73 might be a useful single marker for diagnosing significant 12926553 fibrosis and LY-2409021 cirrhosis in patients with chronic HBV infections. The first question is why serum GP73 concentration correlated with liver stiffness? Based on recently reports, serum GP73 concentration related with progression of chronic liver diseases [13,20]. Different with other HCC marker, increased serum GP73 is related to hepatic impairment and chronic fibrosis [21,20]. In patients with Wilson disease, serum GP73 levels were associated with liver inflammation, fibrosis, and dysplasia, rather than copper overload [22]. More importantly, other experimental research showed that hepatic stellate cellsFibrosis grading 4 3.5 3 2.5 2 1.5 1 0.5 GP73 (per 10 ng/mL) ALB (per 10 g/L) PLT (per 10 6109/L) 0.25 1.22 2.21 2.64 3.37 3.73 6.59 8.00 0.01 0.88 0.86 0.86 0.86 0.87 0.87 0.91 0.95 0.00 0.08 2.02 6.62 9.39 15.17 18.41 52.65 70.86 30.62 18.03 30.87 0.771 0.155 0.010 0.002 ,.0001 ,.0001 ,.0001 ,.0001 ,.0001 ,.0001 ,.0001 1.010 0.927 0.992 1.007 0.895 0.990 1.014 0.960 0.20.08 0.02 20.01 0.Note: Adjusted the factors including Sex, Age, ALT, total bilirubin, albumin, and platelet. doi:10.1371/journal.pone.0053862.tGP73, a Marker for Evaluating HBV ProgressionFigure 3. Serum GP73 concentration was related with levels of different biochemical marker. A and B: serum GP73 concentration was correlated with ALT in patients with ALT 80 U/L, but nearly normal ALT was not. Although different HBV DNA levels had their different GP73 concentration (C), the correlation was not significant (D). Sample number may be one of most important causes. GP73 were also correlated with total bilirubin (F), especially, significantly correlated with serum ALB negatively (E). doi:10.1371/journal.pone.0053862.gare also expressed GP73 [23]. This result consistent with our data, and indicated that more hepatic stellate cells activation, more significant fibrosis, and resulting in serum GP73 more increasing. Strict adherence to practice guidelines of chronic hepatitis B, will make a number of patients with nearly normal ALT lost opportunities of receiving antiviral therapy. In fact, recommendedFigure 15755315 4. GP73 were stained in different liver tissue. GP73 was stained in brown. Arrow indicated positive cells. A: mild fibrosis (S1); B: significant fibrosis (S2); C: severe fibrosis (S3?); D: cirrhosis (S4). doi:10.1371/journal.pone.0053862.gALT thresholds may not 
absolutely reflect disease activity or degree of fibrosis [24]. More importantly, significant fibrosis ( F2, or S2), or moderate hepatocytes injury (G2) are markers for beginning antiviral therapy in patients with chronic hepatitis B, based on present guideline [25]. Compared with other multiparameter prediction models for grading fibrosis, GP73 is a single marker, which can be analysis with general enzyme-linked immunosorbent method. This new marker may be con.ScussionThe ultimate aim of fibrosis grading is provided clinicians with accurate information for treatment decision and prognosis judgment. Identifying significant fibrosis is also one of critical factors for treatment decision, especially for patients with mild abnormal ALT [18]. Avoided or reduced times of liver biopsy, but obtained pathological information from liver tissue, is always pursued by clinicians. Multi-marker combination can provide more accurate information about fibrosis [19], but result in increasing the patient’s expenditure and clinician’s working load. Based on our present data, GP73 might be a useful single marker 
for diagnosing significant 12926553 fibrosis and cirrhosis in patients with chronic HBV infections. The first question is why serum GP73 concentration correlated with liver stiffness? Based on recently reports, serum GP73 concentration related with progression of chronic liver diseases [13,20]. Different with other HCC marker, increased serum GP73 is related to hepatic impairment and chronic fibrosis [21,20]. In patients with Wilson disease, serum GP73 levels were associated with liver inflammation, fibrosis, and dysplasia, rather than copper overload [22]. More importantly, other experimental research showed that hepatic stellate cellsFibrosis grading 4 3.5 3 2.5 2 1.5 1 0.5 GP73 (per 10 ng/mL) ALB (per 10 g/L) PLT (per 10 6109/L) 0.25 1.22 2.21 2.64 3.37 3.73 6.59 8.00 0.01 0.88 0.86 0.86 0.86 0.87 0.87 0.91 0.95 0.00 0.08 2.02 6.62 9.39 15.17 18.41 52.65 70.86 30.62 18.03 30.87 0.771 0.155 0.010 0.002 ,.0001 ,.0001 ,.0001 ,.0001 ,.0001 ,.0001 ,.0001 1.010 0.927 0.992 1.007 0.895 0.990 1.014 0.960 0.20.08 0.02 20.01 0.Note: Adjusted the factors including Sex, Age, ALT, total bilirubin, albumin, and platelet. doi:10.1371/journal.pone.0053862.tGP73, a Marker for Evaluating HBV ProgressionFigure 3. Serum GP73 concentration was related with levels of different biochemical marker. A and B: serum GP73 concentration was correlated with ALT in patients with ALT 80 U/L, but nearly normal ALT was not. Although different HBV DNA levels had their different GP73 concentration (C), the correlation was not significant (D). Sample number may be one of most important causes. GP73 were also correlated with total bilirubin (F), especially, significantly correlated with serum ALB negatively (E). doi:10.1371/journal.pone.0053862.gare also expressed GP73 [23]. This result consistent with our data, and indicated that more hepatic stellate cells activation, more significant fibrosis, and resulting in serum GP73 more increasing. Strict adherence to practice guidelines of chronic hepatitis B, will make a number of patients with nearly normal ALT lost opportunities of receiving antiviral therapy. In fact, recommendedFigure 15755315 4. GP73 were stained in different liver tissue. GP73 was stained in brown. Arrow indicated positive cells. A: mild fibrosis (S1); B: significant fibrosis (S2); C: severe fibrosis (S3?); D: cirrhosis (S4). doi:10.1371/journal.pone.0053862.gALT thresholds may not absolutely reflect disease activity or degree of fibrosis [24]. More importantly, significant fibrosis ( F2, or S2), or moderate hepatocytes injury (G2) are markers for beginning antiviral therapy in patients with chronic hepatitis B, based on present guideline [25]. Compared with other multiparameter prediction models for grading fibrosis, GP73 is a single marker, which can be analysis with general enzyme-linked immunosorbent method. This new marker may be con.