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
Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to 〉 75% ...Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to 〉 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged 〉 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8^+T cells and regulatory T cells or Thl and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of HCC.展开更多
AIM: G1896A mutation in precore or A1762T/G1764Amutations in basal core promoter are suspected to be responsible for patients with detectable level of HBV DNA in serum after seroconversion from HBeAg to anti-Hbe. Howe...AIM: G1896A mutation in precore or A1762T/G1764Amutations in basal core promoter are suspected to be responsible for patients with detectable level of HBV DNA in serum after seroconversion from HBeAg to anti-Hbe. However, G1896A variant has impaired, while A1762T/ G1764A variant may have intact replication ability. They themselves or their coexistence status may play different roles in such meaningless seroconversion. For these reasons, the significances of these two types of mutations were comparatively investigated in this study. METHODS: One hundred and sixty-five sera with positive anti-Hbe and HBV DNA were collected from different patients. Mutations of G1896A and A1762T/G1764A among these serum samples were detected using competitively differentiated PCR. HBV DNA was demonstrated using real-time quantitative PCR. RESULTS: G1896A and/or A1762T/G1764A mutations were detected in 89.1% (147/165) out of patients with detectable HBV DNA in serum after HBeAg-to-anti-Hbe seroconversion. The positive rate of G1896A variants was significantly higher than that of A1762T/G1764A mutations (77.6% vs 50.3%, X2 = 26.61, P<0.01). The coexistence positive rate of these two types of mutations was 38.8% (64/165). Coexistence mutations were found in 77.1% (64/83) out of sera with A1762T/G1764A mutations, and in 50.0% (64/128) out of sera with G1896A mutation. Compared with variants with G1896A mutation only, the coexistence mutations were predominant in patients with high level of serum HBV DNA, and related to higher total bilirubin, lower serum albumin and progressive liver diseases. CONCLUSION: The coexistence of G1896A mutation and A1762T/G1764A mutations is very common, and responsible for the major cases with high level of HBV DNA in serum and progressive liver diseases after HBeAg-to-anti-Hbe seroconversion. This coexistence mutation variant may have higher pathogenicity and replication ability.展开更多
AIM: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. METHODS: Hepatitis B viral DNA was isolated from HBV carr...AIM: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. METHODS: Hepatitis B viral DNA was isolated from HBV carriers' semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction. RESULTS: Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5×10^7 and 1.67×10^7 copies of HBV DNA per mL in two HBV infected patients' sera, while 2.14×10^5 and 3.02×10^5 copies of HBV DNA per mL in the semen. CONCLUSION: Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen.展开更多
Hepatitis C virus(HCV)affects 130-210 million people worldwide and is one of the major risk factors for hepatocellular carcinoma.Globally,at least one third of hepatocellular carcinoma cases are attributed to HCV infe...Hepatitis C virus(HCV)affects 130-210 million people worldwide and is one of the major risk factors for hepatocellular carcinoma.Globally,at least one third of hepatocellular carcinoma cases are attributed to HCV infection,and 350000 people died from HCV related diseases per year.There is a great geographical variation of HCV infection globally,with risk factors for the HCV infection differing in various countries.The progression of chronic hepatitis C to end-stage liver disease also varies in different study populations.A long-term follow-up cohort enrolling participants with asymptomatic HCV infection is essential for elucidating the natural history of HCV-caused hepatocellular carcinoma,and for exploring potential seromarkers that have high predictability for risk of hepatocellular carcinoma.However,prospective cohorts comprising individuals with HCV infection are still uncommon.The risk evaluation of viral load elevation and associated liver disease/cancer in HCV(REVEAL-HCV)study has followed a cohort of 1095 residents seropositive for antibodies against hepatitis C virus living in seven townships in Taiwan for more than fifteen years.Most of them have acquired HCV infection through iatrogenic transmission routes.As the participants in the REVEALHCV study rarely receive antiviral therapies,it provides a unique opportunity to study the natural history of chronic HCV infection.In this review,the prevalence,risk factors and natural history of HCV infection are comprehensively reviewed.The study cohort,data collection,and findings on liver disease progression of the REVEAL-HCV study are described.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Supported by National Natural Science Foundation of China,No. 81025015 and No. 30921006
文摘Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to 〉 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged 〉 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8^+T cells and regulatory T cells or Thl and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of HCC.
基金Supported by the Science Foundation of Guangdong Province,No. 99M04801G
文摘AIM: G1896A mutation in precore or A1762T/G1764Amutations in basal core promoter are suspected to be responsible for patients with detectable level of HBV DNA in serum after seroconversion from HBeAg to anti-Hbe. However, G1896A variant has impaired, while A1762T/ G1764A variant may have intact replication ability. They themselves or their coexistence status may play different roles in such meaningless seroconversion. For these reasons, the significances of these two types of mutations were comparatively investigated in this study. METHODS: One hundred and sixty-five sera with positive anti-Hbe and HBV DNA were collected from different patients. Mutations of G1896A and A1762T/G1764A among these serum samples were detected using competitively differentiated PCR. HBV DNA was demonstrated using real-time quantitative PCR. RESULTS: G1896A and/or A1762T/G1764A mutations were detected in 89.1% (147/165) out of patients with detectable HBV DNA in serum after HBeAg-to-anti-Hbe seroconversion. The positive rate of G1896A variants was significantly higher than that of A1762T/G1764A mutations (77.6% vs 50.3%, X2 = 26.61, P<0.01). The coexistence positive rate of these two types of mutations was 38.8% (64/165). Coexistence mutations were found in 77.1% (64/83) out of sera with A1762T/G1764A mutations, and in 50.0% (64/128) out of sera with G1896A mutation. Compared with variants with G1896A mutation only, the coexistence mutations were predominant in patients with high level of serum HBV DNA, and related to higher total bilirubin, lower serum albumin and progressive liver diseases. CONCLUSION: The coexistence of G1896A mutation and A1762T/G1764A mutations is very common, and responsible for the major cases with high level of HBV DNA in serum and progressive liver diseases after HBeAg-to-anti-Hbe seroconversion. This coexistence mutation variant may have higher pathogenicity and replication ability.
基金Supported by Research Fund for the Control of Infectious Diseases and Research Grant Committee of Hong Kong Government
文摘AIM: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. METHODS: Hepatitis B viral DNA was isolated from HBV carriers' semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction. RESULTS: Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5×10^7 and 1.67×10^7 copies of HBV DNA per mL in two HBV infected patients' sera, while 2.14×10^5 and 3.02×10^5 copies of HBV DNA per mL in the semen. CONCLUSION: Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen.
文摘Hepatitis C virus(HCV)affects 130-210 million people worldwide and is one of the major risk factors for hepatocellular carcinoma.Globally,at least one third of hepatocellular carcinoma cases are attributed to HCV infection,and 350000 people died from HCV related diseases per year.There is a great geographical variation of HCV infection globally,with risk factors for the HCV infection differing in various countries.The progression of chronic hepatitis C to end-stage liver disease also varies in different study populations.A long-term follow-up cohort enrolling participants with asymptomatic HCV infection is essential for elucidating the natural history of HCV-caused hepatocellular carcinoma,and for exploring potential seromarkers that have high predictability for risk of hepatocellular carcinoma.However,prospective cohorts comprising individuals with HCV infection are still uncommon.The risk evaluation of viral load elevation and associated liver disease/cancer in HCV(REVEAL-HCV)study has followed a cohort of 1095 residents seropositive for antibodies against hepatitis C virus living in seven townships in Taiwan for more than fifteen years.Most of them have acquired HCV infection through iatrogenic transmission routes.As the participants in the REVEALHCV study rarely receive antiviral therapies,it provides a unique opportunity to study the natural history of chronic HCV infection.In this review,the prevalence,risk factors and natural history of HCV infection are comprehensively reviewed.The study cohort,data collection,and findings on liver disease progression of the REVEAL-HCV study are described.