Management of patients with pre-therapeutic advanced liver fibrosis following HCV eradication

After the Storm: Persistent Molecular Alterations Following HCV Cure

The development of direct-acting antivirals (DAAs) against hepatitis C virus (HCV) has revolutionized the management of this pathology, as their use allows viral elimination in a large majority of patients. Nonetheless, HCV remains a major public health problem due to the multiple challenges associated with its diagnosis, treatment availability and development of a prophylactic vaccine. Moreover, HCV-cured patients still present an increased risk of developing hepatic complications such as hepatocellular carcinoma. In the present review, we aim to summarize the impact that HCV infection has on a wide variety of peripheral and intrahepatic cell populations, the alterations that remain following DAA treatment and the potential molecular mechanisms implicated in their long-term persistence. Finally, we consider how recent developments in single-cell multiomics could refine our understanding of this disease in each specific intrahepatic cell population and drive the field to explore new directions for the development of chemo-preventive strategies.

Clinical Significance of Evaluation of Monocytic Receptors in Patients with Hepatitis C Virus Infection

Monocytes in hepatitis C virus (HCV) infection play a critical role in chronic liver inflammation and fibrosis. We studied circulating monocytes and monocyte receptors in patients with HCV infection who were naive to treatment and those who received direct acting antiviral therapy and achieved sustained virological response. CD64+ CCR2+ (M1-like) and CD206+ CD163+ CX3CR1+ (M2-like) monocyte numbers and receptor expression were evaluated by flow cytometry. Higher expression of the monocyte chemokine receptor CCR2 predicted the severity of liver fibrosis, independent of successful treatment and viral clearance (R2 = 0.235, p = 0.002), whereas monocyte CX3CR1 expression was lower in both treated and untreated patients compared with controls (p = 0.011). The expression of the scavenger receptor CD163 was lower in patients with successful treatment (p = 0.005), supporting its role as a marker of treatment response. CD64+ CCR2+ (M1-like) and CD206+ CD163+ CX3CR1+ (M2-like) monocyte numbers were not altered with fibrosis progression or treatment response. Our findings reflect the diverse functions of monocytes in liver inflammation, fibrosis, and therapy. However, HCV clearance did not lead to complete monocyte reconstitution. Targeting monocytes and their chemokine receptors bears therapeutic potential to reduce liver fibrosis and improve disease outcome.

Physiomimetic In Vitro Human Models for Viral Infection in the Liver

Viral hepatitis is a leading cause of liver morbidity and mortality globally. The mechanisms underlying acute infection and clearance, versus the development of chronic infection, are poorly understood. In vitro models of viral hepatitis circumvent the high costs and ethical considerations of animal models, which also translate poorly to studying the human-specific hepatitis viruses. However, significant challenges are associated with modeling long-term infection in vitro. Differentiated hepatocytes are best able to sustain chronic viral hepatitis infection, but standard two-dimensional models are limited because they fail to mimic the architecture and cellular microenvironment of the liver, and cannot maintain a differentiated hepatocyte phenotype over extended periods. Alternatively, physiomimetic models facilitate important interactions between hepatocytes and their microenvironment by incorporating liver-specific environmental factors such as three-dimensional ECM interactions and co-culture with non-parenchymal cells. These physiologically relevant interactions help maintain a functional hepatocyte phenotype that is critical for sustaining viral hepatitis infection. In this review, we provide an overview of distinct, novel, and innovative in vitro liver models and discuss their functionality and relevance in modeling viral hepatitis. These platforms may provide novel insight into mechanisms that regulate viral clearance versus progression to chronic infections that can drive subsequent liver disease.

Physiologically relevant microsystems to study viral infection in the human liver

Viral hepatitis is a leading cause of liver disease and mortality. Infection can occur acutely or chronically, but the mechanisms that govern the clearance of virus or lack thereof are poorly understood and merit further investigation. Though cures for viral hepatitis have been developed, they are expensive, not readily accessible in vulnerable populations and some patients may remain at an increased risk of developing hepatocellular carcinoma (HCC) even after viral clearance. To sustain infection in vitro, hepatocytes must be fully mature and remain in a differentiated state. However, primary hepatocytes rapidly dedifferentiate in conventional 2D in vitro platforms. Physiologically relevant or physiomimetic microsystems, are increasingly popular alternatives to traditional two-dimensional (2D) monocultures for in vitro studies. Physiomimetic systems reconstruct and incorporate elements of the native cellular microenvironment to improve biologic functionality in vitro. Multiple elements contribute to these models including ancillary tissue architecture, cell co-cultures, matrix proteins, chemical gradients and mechanical forces that contribute to increased viability, longevity and physiologic function for the tissue of interest. These microsystems are used in a wide variety of applications to study biological phenomena. Here, we explore the use of physiomimetic microsystems as tools for studying viral hepatitis infection in the liver and how the design of these platforms is tailored for enhanced investigation of the viral lifecycle when compared to conventional 2D cell culture models. Although liver-based physiomimetic microsystems are typically applied in the context of drug studies, the platforms developed for drug discovery purposes offer a solid foundation to support studies on viral hepatitis. Physiomimetic platforms may help prolong hepatocyte functionality in order to sustain chronic viral hepatitis infection in vitro for studying virus-host interactions for prolonged periods.

Metabolic dysfunction and cancer in HCV: Shared pathways and mutual interactions

HCV hijacks many host metabolic processes in an effort to aid viral replication. The resulting hepatic metabolic dysfunction underpins many of the hepatic and extrahepatic manifestations of chronic hepatitis C (CHC). However, the natural history of CHC is also substantially influenced by the host metabolic status: obesity, insulin resistance and hepatic steatosis are major determinants of CHC progression toward hepatocellular carcinoma (HCC). Direct-acting antivirals (DAAs) have transformed the treatment and natural history of CHC. While DAA therapy effectively eradicates the virus, the long-lasting overlapping metabolic disease can persist, especially in the presence of obesity, increasing the risk of liver disease progression. This review covers the mechanisms by which HCV tunes hepatic and systemic metabolism, highlighting how systemic metabolic disturbance, lipotoxicity and chronic inflammation favour disease progression and a precancerous niche. We also highlight the therapeutic implications of sustained metabolic dysfunction following sustained virologic response as well as considerations for patients who develop HCC on the background of metabolic dysfunction.

Liver Disease Outcomes after Sustained Virological Response in Patients with Chronic Hepatitis C Infection Treated with Generic Direct-Acting Antivirals

The introduction of generic direct-acting antivirals (DAAs) in Egypt is associated with a superior cure rate of hepatitis C virus (HCV) infection. However, the course of progressive liver damage and developing liver related complications in patients with sustained virologic response (SVR) remain unclear. This study was designed to examine the long-term outcomes of generic DAA-induced virological cure in a real-life cohort of HCV patients with or without comorbid schistosomiasis. We prospectively enrolled a cohort of 506 recently cured HCV patients (437 Child-Pugh class A [Child-A] and 69 Child-Pugh class B [Child-B]). All patients were clinically evaluated at different time points during a 2-year follow-up (November 2018 to February 2021). Over the course of treatment and follow-up, 77 (15.2%) patients (42 [9.6%] Child-A and 35 [50.7%] Child-B) experienced complications at different time points. The overall mortality rate was approximately 1/1,000 person-years. The incidence of hepatic insufficiency was approximately 5.5/1,000 person-years, and that of de novo hepatocellular carcinoma (HCC) was approximately 8.3/1,000 person-years. A sustained improvement in liver indices up to 2 years of follow-up was observed. In the Cox regression model, pretreatment decompensated cirrhosis predicted the occurrence of adverse liver events and HCC after therapy. In conclusion, in HCV patients with advanced cirrhosis or coexisting hepatic schistosomiasis, generic DAA-induced SVR remains robust with favorable clinical outcomes although the risk of hepatocarcinogenesis cannot be eliminated. Surveillance of patients with treated HCV infection is an important aspect of postcure care for early detection and management of liver disease-related adverse events.

Epidemiological projections of viral-induced hepatocellular carcinoma in the perspective of WHO global hepatitis elimination

Hepatitis B is an eminent risk factor for hepatocellular carcinoma (HCC) in Southeast Asia and sub-Saharan Africa, whereas hepatitis C is a key risk factor for HCC in Western Europe and North America. Increased awareness of the global burden of viral hepatitis resulted, in May 2016, in the adoption of the first global health sector strategy on viral hepatitis by the World Health Assembly, which calls for the elimination of viral hepatitis as a public health threat by 2030. Although the incidence of liver cancer resulting from viral infections has increased since the 1990s, the implementation of public health interventions, such as hepatitis B vaccination and antiviral therapies might have reduced the global burdens of HCC. Hepatitis B immunization in infancy has been associated with a reduction in the risk of infant fulminant hepatitis, chronic liver disease, and HCC in Taiwan. Achieving viral hepatitis elimination by 2030 can be accelerated by improving the access to HCC screening programs. HCC surveillance programs in developed countries must be refined to increase an access to personalized surveillance program, whereas the limited access to surveillance and treatment of HCC in developing countries remains a significant public health issue.

Stratification of Hepatocellular Carcinoma Risk Following HCV Eradication or HBV Control

Hepatocellular carcinoma (HCC) incidence has dramatically decreased in patients infected with HCV and HBV due to the widespread use of highly effective antiviral agents. Nevertheless, a substantial proportion of patients with advanced fibrosis or cirrhosis following HCV clearance of in case of HBV control whatever the stage of fibrosis remains at risk of liver cancer development. Cancer predictors in these virus-free patients include routine parameters estimating coexisting comorbidities, persisting liver inflammation or function impairment, and results of non-invasive tests which can be easily combined into HCC risk scoring systems. The latter enables stratification according to various liver cancer incidences and allocation of patients into low, intermediate or high HCC risk probability groups. All international guidelines endorse lifelong surveillance of these patients using semi-annual ultrasound, with known sensibility issues. Refining HCC prediction in this growing population ultimately will trigger personalized management using more effective surveillance tools such as contrast-enhanced imaging techniques or circulating biomarkers while taking into account cost-effectiveness parameters.