Hepatitis C virus core antigen testing: Role in diagnosis, disease monitoring and treatment

While hepatitis B virus(HBV)screening relies on hepatitis B surface antigen to confirm HBV infection since the early days of hepatitis B disease management,hepatitis C virus(HCV)infection screening is based on anti-HCV testing which does not discriminate active from past infection.Thus to confirm infection HCV RNA testing has been required;recently a HCV core antigen assay became widely commercially available which could serve to confirm infection.That assay is less sensitive than current HCV RNA assays,but as more than 50%of anti-HCV positive persons will be HCV core antigen positive,HCV core antigen testing can be a cost effective and reflex test to confirm HCV infection in anti-HCV positive individuals and will be easier as it can be applied on the same platform.For treatment monitoring,more data need to be generated,but the early data available at present suggest that HCV core antigen may be an alternative to HCV RNA monitoring.With direct antivirals,HCV core antigen could even be superior to HCV RNA testing,as direct antivirals might already prevent virus formation when HCV core antigen is still produced and thereby correlates better with eventual viral clearance.

Significance of hepatitis B virus surface antigen, hepatitis C virus expression in hepatocellular carcinoma and pericarcinomatous tissues

AIM： To investigate the correlation between hepatitis B virus surface antigen （HBsAg）, hepatitis C virus （HCV） expression in hepatocellular carcinoma （HCC）, the HAI score of the noncancerous region of the liver and the serum Alpha fetoprotein （AFP） level. METHODS： The patterns of HBsAg and HCV in 100 cases of HCC and their surrounding liver tissues were studied on paraffin-embedded sections with immunohistochemistry, the histological status was determined by one pathologist and one surgeon simultaneously using the hepatitis activity index （HAIl score, and AFP was detected by radioimmunity. The study included 100 consecutive patients who underwent curative resection for HCC. Based on HBsAg and HCV expression, the patients were classified into 4 groups： patients positive for HBsAg （HBsAg group）, patients positive for HCV （HCV group）, patients negative for both HCV and HBsAg （NBNC group） and patients positive for both HBsAg and HCV （BC group）. RESULTS： The BC group had significantly higher HAI scores than the other three groups. （BC 〉 HCV 〉 HBsAg 〉 NBNC）. HBV and HCV virus infection was positively correlated with HAI （rs = 0.39, P = 0.00011. The positive rate of AFP （85.7%） and the value of AFP （541.2 ng/mL） in the group with HBV and HCV co-infection were the highest among the four groups. The positive rate （53.3%） of AFP and the value of AFP （ 53.3 ng/mL） in the group with none-infection of HBV and HCV were the lowest. HBV and HCV virus infection was positively correlated with AFP（rs = 0.38, P = 0.0001）. CONCLUSION： The AFP increase in patients with liver cancer was positively correlated with the infection of HBV and HCV. The-serum AFP elevation by the infection of HBV and HCV is one of mechanisms which lead to hepatocarcinogenesis, and the antivirus intervening treatment of hepatitis is significant for the prognosis of liver cancer. From our Spearman＇s rank correlation analysis, we can conclude that the severity of virally induced inflammation is correlated with HBsAg and HCV expression in HCC tissues and noncancerous tissues. Prior co-infection of HBV in HCV patients may be an adverse risk factor for intrahepatic inflammation.

Post-liver transplant hepatitis C virus recurrence: An unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient’s immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Clinical application and analysis of hepatitis C virus NS3 antigen detection by ELISA in human serum

Background Hepatitis C virus （HCV） core antigen assays have been produced to exclude infectious donations collected during the preseroconversion window phase （PWP）. For the same purpose, we evaluated the specificity and sensitivity of a novel hepatitis C virus NS3 antigen detection immunoassay and the application of this assay in clinical diagnosis. Methods Samples from 77 healthy subjects, 173 anti-HCV positive patients and 3708 hepatitis patients other than HCV positive were tested with the HCV NS3 antigen assay. Some HCV NS3 antigen positive samples were further validated with HCV-RNA, neutralization and immunodot assays. Twenty-five sequential samples from 11 HCV NS3 antigen positive patients were subjected to kinetic study. Results Only 48 （1.3%） of 3708 anti-HCV negative samples were positive for HCV NS3 antigen. Among them, 44 of 3030 samples from patients only infected with HBV were HCV NS3 antigen positive, 4 of the 445 samples from patients infected with other type hepatitis were HCV NS3 antigen positive. In addition, 42 （24.3%） of 173 anti-HCV positive samples were HCV NS3 antigen positive and all 77 samples from healthy subjects were negative to HCV NS3 antigen assay. Of the 15 HCV NS3 antigen positive samples, 9 （60%） were HCV-RNA positive. The neutralization and positive percentage of immunodot assay for 23 HCV NS3 antigen positive sera were 87.0% （20/23） and 69.6% （16/23） respectively. Of the 25 sequential samples from 11 HCV NS3 antigen positive patients, there was a negative correlation between the OD values and the duration of test （r=-0.989, P〈0.05）, and there were correlations among their HCV NS3 antigen, HCV-RNA and anti-HCV Utres. The anti-HCV antibodies of two sera were detected while their OD values of HCV NS3 antigen decreased gradually. Conclusions The HCV NS3 antigen detection assay showed perfect specificity and high sensitivity. Thus, it would be useful and economical as a routine test in laboratories for early diagnosis of HCV infection and prevention.

HCV核心抗原动态监测抗HCV疗效的临床研究(英文)

Objective To evaluate the performance of Hepatitis C virus (HCV) core antigen and HCV RNA PCR in the determining of the efficacy of HCV antiviral therapy in patients infected with HCV.Methods HCV core antigen and HCV RNA were measured in sera of 35 chronic HCV infected Chinese patients.Concentrations of HCV core antigen and HCV RNA were analyzed at 5 time points before,during and at the end of antiviral therapy.Results This study showed that the HCV core antigen and HCV RNA concentrations in 35 HCV patients were significantly correlated.Decrease of HCV core antigen and HCV RNA concentrations at the 4th,12th,24th and 48th week were observed during the antiviral therapy.However,HCV core antigen levels at week 12 and 24 of therapy were significantly lower than those at week 4 (P<0.05).In contrast,no further decrease was observed in HCV RNA concentrations at weeks 12 and 24 (P>0.05).HCV core antigen testing may be advantageous in some cases,in particular,the low levels of HCV core antigen at week 4 may be predictive of satisfactory outcome of treatment.Conclusions HCV core antigen represents a stable and sensitive marker of viral replication and could be used to monitor the clinical efficacy of HCV antiviral therapy.