Alpha-1 antitrypsin is a potential biomarker for hepatitis B.

BACKGROUND: Function exertion of specific proteins are key factors in disease progression, thus the systematical identification of those specific proteins is a prerequisite to understand various diseases. Though many proteins have been verified to impact on hepatitis, no systematical protein screening has been documented to hepatitis B virus (HBV) induced hepatitis, hindering the comprehensive understanding to this severe disease. AIM: To identify the major proteins in the progression of HBV infection from mild stage to severe stage. METHODS: We performed an integrated strategy by combining two-dimensional electrophoresis (2-DE), peptide mass fingerprinting (PMF) analysis, and tissue microarray techniques to screen the functional proteins and detect the localization of those proteins. RESULTS: Interestingly, MS/MS identification revealed the expression level of alpha-1 antitrypsin (AAT) was significantly elevated in serum samples from patients with severe chronic hepatitis. Immunoblotting with a specific AAT antibody confirmed that AAT is highly expressed in serum samples from patients with hepatic carcinoma and severe chronic hepatitis. Furthermore, we observed that AAT is with highest expression in normal tissue and cells, but lowest in hepatic carcinoma and severe chronic hepatitis tissues and cells, suggesting the specific secretion of AAT from tissues and cells to serum. CONCLUSION: These results suggest the possibility of AAT as a potential biomarker for hepatitis B in diagnosis.

Science letters: Proteomic analysis of differentially expressed proteins in mice with concanavalin A-induced hepatitis.

OBJECTIVE: To find new protein biomarkers for the detection and evaluation of liver injury and to analyze the relationship between such proteins and disease progression in concanavalin A (Con A)-induced hepatitis. METHODS: Twenty-five mice were randomly divided into five groups: an untreated group, a control group injected with phosphate buffered saline (PBS), and groups with Con A-induced hepatitis evaluated at 1, 3 and 6 h. Two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identify differences in protein expression among groups. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to verify the results. RESULTS: In mice with Con A-induced hepatitis, expression levels of four proteins were increased: RIKEN, fructose bisphosphatase 1 (fbp1), ketohexokinase (khk), and Chain A of class pi glutathione S-transferase. Changes in fbp1 and khk were confirmed by qRT-PCR. CONCLUSION: Levels of two proteins, fbp1 and khk, are clearly up-regulated in mice with Con A-induced hepatitis.

[PD-L1 expression in circulating dendritic cells of patients with chronic hepatitis B].

OBJECTIVE: To determine the PD-L1 expression levels in circulating dendritic cells(DCs) of patients with HBeAg positive chronic hepatitis B, and to investigate the effects of anti-PD-L1 antibody on DCs stimulating capacity of allogeneic lymphocytes. METHODS: DCs were separated and induced from 22 HBeAg positive chronic hepatitis B patients (CHB), 8 acute resolved hepatitis B patients (AHB) and 10 healthy blood donors. PD-L1 and PD-L2 expression in DCs were determined using real-time RT-PCR and flow cytometry. The potential of circulating DCs on the proliferation of allogeneic T cells was detected and a specific monoclonal antibody against PD-L1 was used in alternative experiments. Serum HBV-DNA titers were measured using real-time PCR, and HBV markers and liver function were also evaluated. RESULT: The expression of PD-L1 but not PD-L2 was upregulated in circulating DCs of CHB patients, compared to AHB patients and healthy controls (both P<0.01). CHB patients with greater than 106 copies /ml of serum HBV DNA loads had a higher level of PD-L1 in circulating DCs than those with less than 106 copies/ml (P<0.05), and the high expression of PD-L1 in DCs was positively correlated with the plasma viral load. Moreover, the potential of circulating DCs from CHB patients was significantly decreased compared with healthy controls or AHB patients, while the blockade of PD-L1 using anti-PD-L1 monoclonal antibody increased the ability of DCs on the proliferation of allogeneic T cells in vitro. CONCLUSION: High expression of PD-L1 on circulating DCs may be associated with T cell exhaustion and persistent high levels of HBV DNA replication in chronic hepatitis B patients.