Uncommon immune-mediated extrahepatic manifestations of HCV infection

Chronic Hepatitis C Virus Infection, Extrahepatic Disease and the Impact of New Direct-Acting Antivirals

Chronic hepatitis C virus infection is an important cause of liver cirrhosis, hepatocellular carcinoma and death. Furthermore, it is estimated that about 40-70% of patients develop non-hepatic alterations in the course of chronic infection. Such manifestations can be immune-related conditions, lymphoproliferative disorders and metabolic alterations with serious adverse events in the short and long term. The introduction of new Direct-Acting Antivirals has shown promising results, with current evidence indicating an improvement and remission of these conditions after a sustained virological response.

Morphological Changes in the Oral Mucous Membrane in Viral Hepatitis C Patients: A Cross-Sectional Study

Background: The objective was to reveal the most typical changes in oral mucosa in HCV patients and compare them with those in HCV negative patients. Methods: The study involved 96 HCV patients and 100 patients without HCV who applied to a dental clinic. The content of cytokines IL-2, IL-4, IL-10 and ɤ-INF in the oral fluid was determined by ELISA. Buccal mucosa and gums biopsies passed histological examination. An immunohistochemical study of mucous membrane biopsies was performed using monoclonal mouse antibodies to CD3+ and CD20+. Results: The HCV patients group included 96 (63.5% males), and the non-HCV group included 100 subjects (62.0% males) with lesions of the oral mucous membrane. The lesions of lips and oral mucosa were more frequent in HCV than in the non-HCV group—e.g., erosion (13.5% vs. 1%), cracks in the mouth corners (42.7% vs. 0%), changes in the oral mucosa surface (89.6% vs. 3.0%), hemorrhages (78.1% vs. 0%), etc. The pro-inflammatory IL-2 level was higher and anti-inflammatory IL-4 level was lower in HCV patients compared with those in the non-HCV group. Conclusions: Morphological changes developed in the microvasculature both worsen the tissue trophism and accelerate the healing with differentiation into coarse-fibrous connective tissue. Immunohistochemical findings indicated a decrease in local humoral immune response.

Prevalence and Outcome of Serum Autoantibodies in Chronic Hepatitis C Patients Undergoing Direct-Acting Antiviral Treatment

Background

Chronic immune stimulation by hepatitis C virus (HCV) may cause occurrence of several autoantibodies in infected patients, with or without features of clinically overt autoimmune diseases. The recent introduction of direct-acting antivirals (DAAs) has dramatically changed the natural history of chronic HCV infection. The aim of this study was to assess the effects of DAA therapy on serum autoantibodies in chronic hepatitis C (CHC) patients.

Methods

The medical records of 113 CHC patients were reviewed to assess autoantibody behavior following DAA-directed HCV eradication. Statistical analysis was performed to assess correlations between DAA treatment and autoantibody titers, HCV genotypes, and viral loads.

Results

Anti-nuclear (ANA), anti-smooth muscle cell (ASMA) and anti-mitochondrial (AMA) antibody testing was available in 77 patients; 31 out of 77 patients (40%) had one or more serum autoantibodies prior to treatment. Measurement of autoantibody titers before and after HCV eradication was performed in 20 of 31 patients. DAA treatment significantly affected ANA and ASMA titers, leading to disappearance or reduction of autoantibody titers; conversely, AMA were not influenced by DAA treatment. No correlations were observed between autoantibody specificity and both HCV genotypes and viral loads at baseline. Likewise, serum autoantibody titers were independent of HCV genotypes.

Conclusions

DAA-directed HCV clearance may interrupt chronic immune stimulation by removing the drive for autoantibody induction. The isolated persistence of autoantibodies in the small fraction of patients who did not show clearance following DAA treatment may require long-term vigilance.

Autoantibodies and Rheumatologic Manifestations in Hepatitis C Virus Infection

HCV is a virus that can cause chronic infection which can result in a systemic disease that may include many rheumatologic manifestations such as arthritis, myalgia, sicca syndrome, cryoglobulinemia vasculitis as well as other non-rheumatological disorders (renal failure, onco-haematological malignancies). In this population, the high frequency of rheumatoid factor (45-70%), antinuclear (10-40%) and anticardiolipin (15-20%) antibodies is a B-cell mediated finding sustained by the infection. However, the possibility that a primitive rheumatic pathology may coexist with the HCV infection is not to be excluded thus complicating a differential diagnosis between primitive and HCV-related disorders.

Changes in clinical scenarios, management, and perspectives of patients with chronic hepatitis C after viral clearance by direct-acting antivirals

INTRODUCTION

Hepatitis C virus (HCV) causes a systemic infection inducing hepatic and extrahepatic diseases. These latter involve cardiovascular system, kidney, brain, endocrine, glucose, and lipid metabolism, and the immune system. HCV infection is associated with an increased risk of morbidity and mortality for both hepatic and extrahepatic events. Direct-acting antivirals (DAA), introduced in the most recent years for HCV treatment, are effective in up to 99% of cases and have changed the clinical scenarios and management of these patients.

AREAS COVERED

The literature on the impact of HCV clearance by DAA on both hepatic and extrahepatic disease outcomes has been analyzed and discussed in this review in order to summarize the full therapeutic potential and its weaknesses.

EXPERT OPINION

Patients achieving HCV clearance have improved hepatic and extrahepatic diseases, quality of life and survival. They have lower incidence of cardiovascular disease, type 2 diabetes, kidney damage, and immuno-mediated manifestations. However, the improvements are related to the degree of pre-treatment organ damage. Therefore, a significant percentage of patients with advanced disease remains at risk of morbidity and mortality and must be monitored in the post-treatment. In addition, data emphasize the importance of starting treatment during the early stages of HCV infection.

Impact of DAA-Based Regimens on HCV-Related Extra-Hepatic Damage: A Narrative Review

Two-third of patients with chronic hepatitis C show extrahepatic manifestations due to HCV infection of B lymphocytes, such as mixed cryoglobulinemia and non-Hodgkin B-cell lymphoma, or develop a chronic inflammatory status that may favor the development of adverse cardiovascular events, kidney diseases or metabolic abnormalities.DAAs treatments induce HCV eradication in 95% of treated patients, which also improves the clinical course of extrahepatic manifestations, but with some limitations. After HCV eradication a good compensation of T2DM has been observed, but doubts persist about the possibility of obtaining a stable reduction in fasting glucose and HbA1c levels.Chronic HCV infection is associated with low total and LDL cholesterol serum levels, which however increase significantly after HCV elimination, possibly due to the disruption of HCV/lipid metabolism interaction. Despite this adverse effect, HCV eradication exerts a favorable action on cardiovascular system, possibly by eliminating numerous other harmful effects exerted by HCV on this system.DAA treatment is also indicated for the treatment of patients with mixed cryoglobulinemia syndrome, since HCV eradication results in symptom reduction and, in particular, is effective in cryoglobulinemic vasculitis. Furthermore, HCV eradication exerts a favorable action on HCV-related lymphoproliferative disorders, with frequent remission or reduction of clinical manifestations.There is also evidence that HCV clearance may improve impaired renal functions, but same conflicting data persist on the effect of some DAAs on eGFR.

Human hepatitis viruses-associated cutaneous and systemic vasculitis

Human hepatitis viruses (HHVs) include hepatitis A virus, hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis delta virus, and hepatitis E virus and can cause liver inflammation in their common human host. Usually, HHV is rapidly cleared by the immune system, following acute HHV invasion. The morbidities associated with hepatitis A virus and hepatitis E virus infection occur shortly after their intrusion, in the acute stage. Nevertheless, the viral infectious process can persist for a long period of time, especially in HBV and HCV infection, leading to chronic hepatitis and further progressing to hepatic cirrhosis and liver cancer. HHV infection brings about complications in other organs, and both acute and chronic hepatitis have been associated with clinical presentations outside the liver. Vascular involvement with cutaneous and systemic vasculitis is a well-known extrahepatic presentation; moreover, there is growing evidence for a possible causal relationship between viral pathogens and vasculitis. Except for hepatitis delta virus, other HHVs have participated in the etiopathogenesis of cutaneous and systemic vasculitis via different mechanisms, including direct viral invasion of vascular endothelial cells, immune complex-mediated vessel wall damage, and autoimmune responses with stimulation of autoreactive B-cells and impaired regulatory T-cells. Cryoglobulinemic vasculitis and polyarteritis nodosa are recognized for their association with chronic HHV infection. Although therapeutic guidelines for HHV-associated vasculitis have not yet been established, antiviral therapy should be initiated in HBV and HCV-related systemic vasculitis in addition to the use of corticosteroids. Plasma exchange and/or combined cyclophosphamide and corticosteroid therapy can be considered in patients with severe life-threatening vasculitis manifestations.

Beyond HIV infection: Neglected and varied impacts of CCR5 and CCR5Δ32 on viral diseases

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CCR5 regulates multiple cell types (e.g., T regulatory and Natural Killer cells) and immune responses.

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The effects of CCR5, CCR5Δ32 (variant associated with reduced CCR5 expression) and CCR5 antagonists vary between infections.

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CCR5 affects the pathogenesis of flaviviruses, especially in the brain.

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The genetic variant CCR5Δ32 increases the risk of symptomatic West Nile virus infection.

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The triad “CCR5, extracellular vesicles and infections” is an emerging topic.

The interactions between chemokine receptors and their ligands may affect susceptibility to infectious diseases as well as their clinical manifestations. These interactions mediate both the traffic of inflammatory cells and virus-associated immune responses. In the context of viral infections, the human C-C chemokine receptor type 5 (CCR5) receives great attention from the scientific community due to its role as an HIV-1 co-receptor. The genetic variant CCR5Δ32 (32 base-pair deletion in CCR5 gene) impairs CCR5 expression on the cell surface and is associated with protection against HIV infection in homozygous individuals. Also, the genetic variant CCR5Δ32 modifies the CCR5-mediated inflammatory responses in various conditions, such as inflammatory and infectious diseases. CCR5 antagonists mimic, at least in part, the natural effects of the CCR5Δ32 in humans, which explains the growing interest in the potential benefits of using CCR5 modulators for the treatment of different diseases. Nevertheless, beyond HIV infection, understanding the effects of the CCR5Δ32 variant in multiple viral infections is essential to shed light on the potential effects of the CCR5 modulators from a broader perspective. In this context, this review discusses the involvement of CCR5 and the effects of the CCR5Δ32 in human infections caused by the following pathogens: West Nile virus, Influenza virus, Human papillomavirus, Hepatitis B virus, Hepatitis C virus, Poliovirus, Dengue virus, Human cytomegalovirus, Crimean-Congo hemorrhagic fever virus, Enterovirus, Japanese encephalitis virus, and Hantavirus. Subsequently, this review addresses the impacts of CCR5 gene editing and CCR5 modulation on health and viral diseases. Also, this article connects recent findings regarding extracellular vesicles (e.g., exosomes), viruses, and CCR5. Neglected and emerging topics in “CCR5 research” are briefly described, with focus on Rocio virus, Zika virus, Epstein-Barr virus, and Rhinovirus. Finally, the potential influence of CCR5 on the immune responses to coronaviruses is discussed.

From hepatitis C virus immunoproteomics to rheumatology via cross-reactivity in one table

PURPOSE OF REVIEW

To give an overview of molecular and immunologic data that link hepatitis C virus (HCV) infection to rheumatic diseases in the human host.

RECENT FINDINGS

A high level of peptide sharing exists between immunopositive HCV epitopes and human proteins that, when altered, associate with rheumatic manifestations.

SUMMARY

The findings suggest the involvement of HCV infection in the induction of most rheumatic diseases via a mechanism of autoimmune cross-reactivity.

Rheumatologic manifestations of hepatitis C in the era of direct-acting antiviral agents

Beyond the classic hepatic complications, hepatitis C (HCV) infection is considered as a systemic disease, since extrahepatic manifestations become clinically evident in 40% to 70% of the patients and it can frequently include rheumatic ones. Furthermore, HCV can promote the production of several autoantibodies, thus complicating the differential diagnosis between primitive and HCV-related rheumatic disorders. The recent development of direct-acting antivirals (DAA) against HCV has revolutionized the field, reducing the damage stemming from systemic inflammatory phenomena and persistent immune activation associated with continuous HCV replication. Our review focuses on the main rheumatologic manifestations associated with chronic HCV infection as well as the impact of DAA interferon-free treatments on such extrahepatic clinical involvement.

HCV Extrahepatic Manifestations

Hepatitis C virus (HCV) has been shown to affect many tissues other than liver. However, of the many extrahepatic manifestations (EMs) that have been associated with HCV, including cryoglobulinemia, lymphoma, insulin resistance, type 2 diabetes and neurological disorders, only a few have been shown to be directly related to HCV infection of extrahepatic tissues. HCV-triggered immune-mediated mechanisms account for most of the EMs. It is estimated that up to 74% of patients with chronic hepatitis C can develop at least one EM. All HCV patients with EMs should be considered for antiviral therapy, although not all will resolve with sustained virological response.