AIM:To evaluate the covalently closed circle DNA (cccDNA) level of hepatitis B virus (HBV) in patients' liver and sera. METHODS:HBV DNA was isolated from patients' liver biopsies and sera.A sensitive real-time...AIM:To evaluate the covalently closed circle DNA (cccDNA) level of hepatitis B virus (HBV) in patients' liver and sera. METHODS:HBV DNA was isolated from patients' liver biopsies and sera.A sensitive real-time PCR method,which is capable of differentiation of HBV viral genomic DNA and cccDNA,was used to quantify the total HBV cccDNA.The total HBV viral DNA was quantitated by real-time PCR using a HBV diagnostic kit (PG Biotech,LTD,Shenzhen,China) described previously. RESULTS:For the first time,we measured the level of HBV DNA and cccDNA isolated from ten HBV patients' liver biopsies and sera.In the liver biopsies,cccDNA was detected from all the biopsy samples.The copy number of cccDNA ranged from from 0.03 to 173.1 per cell,the copy number of total HBV DNA ranged from 0.08 to 3 717 per cell.The ratio of total HBV DNA to cccDNA ranged from 1 to 3 406.In the sera, cccDNA was only detected from six samples whereas HBV viral DNA was detected from all ten samples.The ratio of cccDNA to total HBV DNA ranged from 0 to 1.77%.To further investigate the reason why cccDNA could only be detected in some patients' sera,we performed longitudinal studies.The cccDNA was detected from the patients' sera with HBV reactivation but not from the patients' sera without HBV reactivation.The level of cccDNA in the sera was correlated with ALT and viral load in the HBV reactivation patients. CONCLUSION:HBV cccDNA is actively transcribed and replicated in some patients' hepatoo/tes,which is reflected by a high ratio of HBV total DNA vs cccDNA.Detection of cccDNA in the liver biopsy will provide an end-point for the anti-HBV therapy.The occurrence of cccDNA in the sera is an early signal of liver damage,which may be another important clinical parameter.展开更多
Chronic hepatitis B virus (HBV) infection can cause a broad spectrum diseases, including from asymptomatic HBV carriers or cryptic hepatitis, to acute hepatitis, chronic hepatitis, Liver cirrhosis and primary hepatoce...Chronic hepatitis B virus (HBV) infection can cause a broad spectrum diseases, including from asymptomatic HBV carriers or cryptic hepatitis, to acute hepatitis, chronic hepatitis, Liver cirrhosis and primary hepatocellular carcinoma. The variable pattern and clinical outcome of the infection were mainly determined by virological itself factors, host immunological factors and genetic factors as well as the experimental factors. Among the human genetic factors, major candidate or identified genes involved in the process of HBV infection fall into the following categories: (1) genes that mediate the processes of viral entry into hepatocytes, induding genes involved in viral binding, fusion with cellular membrane and transportation in target cells; (2) genes that modulate or control the immune response to HBV infection; (3) genes that participate in the pathological alterations in liver tissue;(4) genes involved in the development of liver cirrhosis and hepatocellular carcinoma associated with chronic HBV infection, including genes related to mother-to-infant transmission of HBV infection; and (5) those that contribute to resistance to antiviral therapies. Most of the reports of human genes associated with HBV infection have currently focused on HLA associations. For example, some investigators reported the association of the HLA class Ⅱ alleles such as DRB1*1302 or HLA-DR13 or DQA1*0501-DQB1*0301-DQB1*1102 haplotypes with acute and/or chronic hepatitis B virus infection, respectively. Several pro-inflammatory cytokines such as Th1 cytokines (including IL-2 and IFN-γ)and TNF-α have been identified to participate the process of viral clearance and host immune response to HBV. In contrast, the Th2 cytokine IL-10 serves as a potent inhibitor of Th1 effector cells in HBV diseases. The MBP polymorphisms in its encoding region were found to be involved in chronic infection. Thus, reports from various laboratories have shown some inconsistencies with regard to the effects of host genetic factors on HBV clearance and pe展开更多
基金SuppoSed by CRCG grant from the University of Hong KongCERG grant from University Grant Council of Hong Kong Research Fund from Science and Technology Commission of Shanghai,China
文摘AIM:To evaluate the covalently closed circle DNA (cccDNA) level of hepatitis B virus (HBV) in patients' liver and sera. METHODS:HBV DNA was isolated from patients' liver biopsies and sera.A sensitive real-time PCR method,which is capable of differentiation of HBV viral genomic DNA and cccDNA,was used to quantify the total HBV cccDNA.The total HBV viral DNA was quantitated by real-time PCR using a HBV diagnostic kit (PG Biotech,LTD,Shenzhen,China) described previously. RESULTS:For the first time,we measured the level of HBV DNA and cccDNA isolated from ten HBV patients' liver biopsies and sera.In the liver biopsies,cccDNA was detected from all the biopsy samples.The copy number of cccDNA ranged from from 0.03 to 173.1 per cell,the copy number of total HBV DNA ranged from 0.08 to 3 717 per cell.The ratio of total HBV DNA to cccDNA ranged from 1 to 3 406.In the sera, cccDNA was only detected from six samples whereas HBV viral DNA was detected from all ten samples.The ratio of cccDNA to total HBV DNA ranged from 0 to 1.77%.To further investigate the reason why cccDNA could only be detected in some patients' sera,we performed longitudinal studies.The cccDNA was detected from the patients' sera with HBV reactivation but not from the patients' sera without HBV reactivation.The level of cccDNA in the sera was correlated with ALT and viral load in the HBV reactivation patients. CONCLUSION:HBV cccDNA is actively transcribed and replicated in some patients' hepatoo/tes,which is reflected by a high ratio of HBV total DNA vs cccDNA.Detection of cccDNA in the liver biopsy will provide an end-point for the anti-HBV therapy.The occurrence of cccDNA in the sera is an early signal of liver damage,which may be another important clinical parameter.
基金Key project grant from Natural Science Foundation of Beijing Municipal Government No:7011005
文摘Chronic hepatitis B virus (HBV) infection can cause a broad spectrum diseases, including from asymptomatic HBV carriers or cryptic hepatitis, to acute hepatitis, chronic hepatitis, Liver cirrhosis and primary hepatocellular carcinoma. The variable pattern and clinical outcome of the infection were mainly determined by virological itself factors, host immunological factors and genetic factors as well as the experimental factors. Among the human genetic factors, major candidate or identified genes involved in the process of HBV infection fall into the following categories: (1) genes that mediate the processes of viral entry into hepatocytes, induding genes involved in viral binding, fusion with cellular membrane and transportation in target cells; (2) genes that modulate or control the immune response to HBV infection; (3) genes that participate in the pathological alterations in liver tissue;(4) genes involved in the development of liver cirrhosis and hepatocellular carcinoma associated with chronic HBV infection, including genes related to mother-to-infant transmission of HBV infection; and (5) those that contribute to resistance to antiviral therapies. Most of the reports of human genes associated with HBV infection have currently focused on HLA associations. For example, some investigators reported the association of the HLA class Ⅱ alleles such as DRB1*1302 or HLA-DR13 or DQA1*0501-DQB1*0301-DQB1*1102 haplotypes with acute and/or chronic hepatitis B virus infection, respectively. Several pro-inflammatory cytokines such as Th1 cytokines (including IL-2 and IFN-γ)and TNF-α have been identified to participate the process of viral clearance and host immune response to HBV. In contrast, the Th2 cytokine IL-10 serves as a potent inhibitor of Th1 effector cells in HBV diseases. The MBP polymorphisms in its encoding region were found to be involved in chronic infection. Thus, reports from various laboratories have shown some inconsistencies with regard to the effects of host genetic factors on HBV clearance and pe