Modeling hepatitis C virus kinetics during liver transplantation reveals the role of the liver in virus clearance.
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ABSTRACT:
SUBMITTER: Shekhtman L
PROVIDER: S-EPMC8608386 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:UnlabelledLiver transplantation (LT) is a unique model to study hepatitis C virus (HCV) entry into hepatocytes. Recent in vitro studies suggest significant changes in the expression of the HCV receptors claudin-1 and occludin after HCV infection. Our aims were: (1) to characterize claudin-1 and occludin expression in grafts from LT recipients and (2) to explore their potential influence on early HCV kinetics and their changes after HCV infection. We included 42 HCV-infected LT recipients and 19 uninfected controls. Claudin-1 and occludin were detected in paraffin-embedded liver biopsies obtained during reperfusion and 3 and 12 months after LT. HCV receptors were characterized by confocal immunofluorescence microscopy; quantification and colocalization studies were performed with dedicated software. Claudin-1 and occludin expression were restricted to the apical pole of hepatocytes. There was a significant correlation between the amount of scavenger receptor B1 at the time of reperfusion and the HCV-RNA decay during the first 24 hours following LT (r = 0.55, P = 0.007). Similarly, there was a significant correlation between the levels of claudin and occludin and the slope of HCV-RNA increase during the first week after LT (r = 0.63, P = 0.005). Occludin and claudin-1 levels increased significantly 12 months after LT (P = 0.03 and P = 0.007, respectively). The expression pattern of both proteins, however, remained unchanged, colocalizing strongly (60%-94%) at the apical membrane of hepatocytes.ConclusionsHCV receptor levels at the time of LT seem to modulate early HCV kinetics. Hepatitis C recurrence after LT was associated with increased levels of claudin-1 and occludin in the hepatocyte cell membrane, although it did not alter their localization within the tight junctions.
| S-EPMC3082584 | biostudies-literature
Project description:UnlabelledChronic hepatitis B (CHB) is prevalent worldwide. The infectious agent, hepatitis B virus (HBV), replicates via an RNA intermediate and is error prone, leading to the rapid generation of closely related but not identical viral variants, including those that can escape host immune responses and antiviral treatments. The complexity of CHB can be further enhanced by the presence of HBV variants with large deletions in the genome generated via splicing (spHBV variants). Although spHBV variants are incapable of autonomous replication, their replication is rescued by wild-type HBV. spHBV variants have been shown to enhance wild-type virus replication, and their prevalence increases with liver disease progression. Single-molecule deep sequencing was performed on whole HBV genomes extracted from samples, including the liver explant, longitudinally collected from a subject with CHB over a 15-year period after liver transplantation. By employing novel bioinformatics methods, this analysis showed that the dynamics of the viral population across a period of changing treatment regimens was complex. The spHBV variants detected in the liver explant remained present posttransplantation, and a highly diverse novel spHBV population as well as variants with multiple deletions in the pre-S genes emerged. The identification of novel mutations outside the HBV reverse transcriptase gene that co-occurred with known drug resistance-associated mutations highlights the relevance of using full-genome deep sequencing and supports the hypothesis that drug resistance involves interactions across the full length of the HBV genome.ImportanceSingle-molecule sequencing allowed the characterization, in unprecedented detail, of the evolution of HBV populations and offered unique insights into the dynamics of defective and spHBV variants following liver transplantation and complex treatment regimens. This analysis also showed the rapid adaptation of HBV populations to treatment regimens with evolving drug resistance phenotypes and evidence of purifying selection across the whole genome. Finally, the new open-source bioinformatics tools with the capacity to easily identify potential spliced variants from deep sequencing data are freely available.
| S-EPMC4984637 | biostudies-literature
Project description:Spontaneous clearance of hepatitis C virus during chronic infection is uncommon. We report the case of a patient who cleared hepatitis C virus during an episode of presumed alcoholic hepatitis. A brief discussion on the immunological aspects of chronic hepatitis C and the impact of alcohol consumption on it is presented as well.
| S-EPMC4611481 | biostudies-literature
Project description:Recurrence of hepatitis C virus (HCV) infection following liver transplantation (LT) is almost universal and can accelerate graft cirrhosis in up to 30% of patients. The development of effective strategies to treat or prevent HCV recurrence after LT remains a major challenge, considering the shortage of donor organs and the accelerated progression of HCV in LT recipients. Standard antiviral therapy with pegylated-interferon plus ribavirin is the current treatment of choice for HCV LT recipients, even though the combination is not as effective as it is in immunocompetent patients. A sustained virological response in the setting of LT improves patient and graft survival, but this is only achieved in 30%-45% of patients and the treatment is poorly tolerated. To improve the efficacy of pre- and post-transplant antiviral therapy, a new class of potent direct-acting antiviral agents (DAAs) has been developed. The aim of this review is to summarize the use of DAAs in LT HCV patients. PubMed, Cochrane Library, MEDLINE, EMBASE, Web of Science and clinical trial databases were searched for this purpose. To date, only three clinical studies on the topic have been published and most of the available data are in abstract form. Although a moderately successful early virological response has been reported, DAA treatment regimens were associated with severe toxicity mitigating their potential usefulness. Moreover, the ongoing nature of data, the lack of randomized studies, the small number of enrolled patients and the heterogeneity of these studies make the results largely anecdotal and questionable. In conclusion, large well-designed clinical studies on DAAs in HCV LT patients are required before these drugs can be recommended after transplantation.
| S-EPMC4110555 | biostudies-literature
Project description:There is little information on the early kinetics of hepatitis delta virus (HDV) and hepatitis B surface antigen (HBsAg) during interferon-? therapy. Here a mathematical model was developed and fitted to frequent HDV and HBsAg kinetic data from 10 patients during the first 28 weeks of pegylated-interferon-?2a (peg-IFN) therapy. Three patients achieved a complete virological response (CVR), defined as undetectable HDV 6 months after treatment stopped with loss of HBsAg and anti-HBsAg seroconversion. After initiation of therapy, a median delay of 9 days (interquartile range [IQR]: 5-15) was observed with no significant changes in HDV level. Thereafter, HDV declined in a biphasic manner, where a rapid first phase lasting for 25 days (IQR: 23-58) was followed by a slower or plateau second phase. The model predicts that the main effect of peg-IFN is to reduce HDV production/release with a median effectiveness of 96% (IQR: 93-99.8). Median serum HDV half-life (t1/2 ) was estimated as 2.9 days (IQR: 1.5-5.3) corresponding to a pretreatment production and clearance of about 10(10) (IQR: 10(9.7) -10(10.7) ) virions/day. None of the patients with flat second phase in HDV achieved CVR. HBsAg kinetics of decline paralleled the second phase of HDV decline consistent with HBsAg-productive-infected cells being the main source of production of HDV, with a median t1/2 of 135 days (IQR: 20-460). The interferon lambda-3 polymorphism (rs12979860) was not associated with kinetic parameters.Modeling results provide insights into HDV-host dynamics, the relationship between serum HBsAg levels and HBsAg-infected cells, IFN's mode of action, and its effectiveness. The observation that a flat second phase in HDV and HBsAg kinetics was associated with failure to achieve CVR provides the basis to develop early stopping rules during peg-IFN treatment in HDV-infected patients.
| S-EPMC4245461 | biostudies-literature
Project description:Purpose of reviewTo review the experience to date and unique challenges associated with liver transplantation in hepatitis C virus (HCV)/HIV-coinfected patients.Recent findingsThe prevalence of cirrhosis and hepatocellular carcinoma is rising among HIV-infected individuals. With careful patient selection and in the absence of HCV infection, HIV-infected and HIV-uninfected liver transplant recipients have comparable posttransplant outcomes. However, in the presence of HCV infection, patient and graft survival are significantly poorer in HIV-infected recipients, who have a higher risk of aggressive HCV recurrence, acute rejection, sepsis, and multiorgan failure. Outcomes may be improved with careful recipient and donor selection and with the availability of new highly potent all-oral HCV direct acting antivirals (DAAs). Although all-oral DAAs have not been evaluated in HIV/HCV-coinfected transplant patients, HIV does not adversely impact treatment success in nontransplant populations. Therefore, there is great hope that HCV can be successful eradicated in HIV/HCV-coinfected transplant patients and will result in improved outcomes. Careful attention to drug-drug interactions with HIV antiretroviral agents, DAAs, and posttransplant immunosuppressants is required.SummaryLiver transplant outcomes are poorer in HIV/HCV-coinfected recipients compared with those with HCV-monoinfection. The new HCV DAAs offer tremendous potential to improve outcomes in this challenging population.
| S-EPMC4807723 | biostudies-literature
Project description:Chronic hepatitis C virus (HCV) infection is the leading cause of death from liver disease and the leading indication for liver transplantation (LT) in the United States and Western Europe. LT represents the best therapeutic alternative for patients with advanced chronic liver disease caused by HCV or those who develop hepatocarcinoma. Reinfection by HCV of the graft is universal and occurs in 95% of transplant patients. This reinfection can compromise graft function and patient survival. In a few cases, the histological recurrence is minimal and non-progressive; however, in most patients it follows a more rapid course than in immunocompetent persons, and frequently evolves into cirrhosis with graft loss. In fact, the five-year and ten-year survival of patients transplanted because of HCV are 75% and 68%, respectively, compared with 85% and 78% in patients transplanted for other reasons. There is also a pattern of recurrence that is very severe, but rare (< 10%), called fibrosing cholestatic hepatitis, which often involves rapid graft loss. Patients who present a negative HCV viremia after antiviral treatment have better survival. Many studies published over recent years have shown that antiviral treatment of post-transplant HCV hepatitis carried out during the late phase is the best option for improving the prognosis of these patients. Until 2011, PEGylated interferon plus ribavirin was the standard of care, resulting in a sustained virological response in around 30% of recipients. The addition of protease inhibitors, such as boceprevir or telaprevir, to the standard of care, or the use of other direct-acting antiviral drugs may involve therapeutic changes in the context of HCV recurrence. This may result a better prognosis for these patients, particularly those with severe recurrence or factors predicting rapid progression of fibrosis. However, the use of these agents in LT still requires clarification in terms of safety and efficacy.
| S-EPMC4248184 | biostudies-literature
Project description:Background: There is a growing interest in the role of circadian regulated pathways in disease pathogenesis. Methods: In a cohort of hepatitis C virus (HCV) infected patients undergoing liver transplantation, we observed differences in early viral infection kinetics of the allograft that associated with the time of liver transplant. Results: A higher frequency of subjects transplanted in the morning showed a rebound in viral RNA levels (n=4/6) during the first week post-surgery. In contrast, no viral rebound was observed in seven subjects transplanted in the afternoon. None of the other parameters previously reported to influence viral replication in the post-transplant setting, such as donor age, cold-ischemia time and length of surgery associated with viral rebound. Conclusions: These observation highlights a role for circadian processes to regulate HCV infection of the liver and warrants further investigation.
| S-EPMC6107978 | biostudies-literature
Project description:To better understand the dynamics of early hepatitis C virus (HCV) infection, we determined how rapidly non-cirrhotic HCV-uninfected liver allografts clear HCV from the circulation of cirrhotic HCV-infected patients at the time of transplantation but before administration of immunosuppression. Specifically, we characterized serum HCV kinetics during the first 90 min of reperfusion for 19 chronically HCV-infected patients transplanted with an HCV-uninfected liver by measuring serum viral load immediately prior to reperfusion (t = 0) and then every 15 min for a total of 90 min (t = 90). Immunosuppression was withheld until all samples were taken to better model primary infection. During this period, rates of viral clearance varied more than 20-fold with a median rate constant of 0.0357 1/min, range 0.0089-0.2169; half-life (minutes) median 19.4, range 3.2-77.8. The majority of viral clearance occurred within the first 60 min. The amount of blood transfused during this 90-min period (a potential confounding variable of this human liver transplant model of primary infection) accounted for 53% and 59% of k (r = 0.53, p = 0.05) and half-life (r = 0.59, p = 0.03) variability, respectively. No other clinical variables tested (age, allograft weight, and degree of reperfusion injury as assessed by peak postoperative ALT or AST) accounted for the remaining variability (p>0.05).In a human liver transplant model of primary infection, HCV rapidly clears the bloodstream. With approximately 90% of clearance occurring in the first 90 minutes of reperfusion, studies of HCV entry inhibition could utilize rate of clearance during this early period as an outcome measure.
| S-EPMC5521768 | biostudies-other
Project description:Hepatitis C virus (HCV) is a major health problem that leads to chronic hepatitis, cirrhosis and hepatocellular carcinoma, being the most frequent indication for liver transplantation in several countries. Unfortunately, HCV re-infects the liver graft almost invariably following reperfusion, with an accelerated history of recurrence, leading to 10%-30% of patients progressing to cirrhosis within 5 years of transplantation. In this sense, some groups have even advocated for not re-transplanting this patients, as lower patient and graft outcomes have been reported. However, the management of HCV recurrence is being optimized and several strategies to reduce post-transplant recurrence could improve outcomes, decrease the rate of re-transplantation and optimize the use of available grafts. Three moments may be the focus of potential actions in order to decrease the impact of viral recurrence: the pre-transplant moment, the transplant environment and the post-transplant management. In the pre-transplant setting, it is not well established if reducing the pre transplant viral load affects the risk for HCV progression after transplant. Obviously, antiviral treatment can render the patient HCV RNA negative post transplant but the long-term benefit has not yet been fully established to justify the cost and clinical risk. In the transplant moment, factors as donor age, cold ischemia time, graft steatosis and ischemia/reperfusion injury may lead to a higher and more aggressive viral recurrence. After the transplant, discussion about immunosuppression and the moment to start the treatment (prophylactic, pre-emptive or once-confirmed) together with new antiviral drugs are of interest. This review aims to help clinicians have a global overview of post-transplant HCV recurrence and strategies to reduce its impact on our patients.
| S-EPMC3664282 | biostudies-other