The lymphoid system in hepatitis C virus infection: autoimmunity, mixed cryoglobulinemia, and Overt B-cell malignancy

Role of hepatitis c virus in hepatocellular carcinoma and neurological disorders: an overview

The hepatitis C virus (HCV) causes serious issues, affecting 71 million people globally. The most common manifestations range from chronic hepatitis to liver cirrhosis, leading to hepatocellular carcinoma. Many mechanisms are known to play an important role in HCV-induced HCC. The interaction of viral proteins with host cells results in oxidative stress damage, liver inflammation, and irregularities in signaling pathways. These results in the activation of oncogenes and metabolic disturbances, liver fibrosis, and angiogenesis. Additionally, some non-coding RNAs (ncRNAs) and toll-like receptors have been identified and play a significant role in HCC development. This virus is also associated with impairment of the central nervous system, resulting in acute or sub-acute encephalopathy and inflammatory disorders. Neurological disorders are associated with the inflammatory responses of many cells, including microglia and astrocytes. Additionally, there are many other extrahepatic manifestations, including neurological disorders such as depression and fatigue, in 50% of infected patients. These manifestations include neuro-invasion, immune-mediated damage, neurotransmitter alterations, sensory-motor polyneuropathy, sensitivity loss, weakness of the leg, and cryoglobulinemia, which significantly results in a reduced quality of life. HCV infection may be improved using an appropriate diagnosis and direct antiviral therapy for sustained virological response. However, the success of therapy depends on the symptoms and organ damage, diagnosis, and therapeutic strategies applied. Some published reports have discussed that HCV is associated with both HCC and neurological disorders. Additionally, it has also been observed that individuals with HCC also develop neurological disorders compared with individuals with HCV alone. This review aims to provide an overview of the latest information about the relationship between HCV-induced HCC and their role in neurological disorders. Additionally, we have also discussed the progress made in the diagnosis, physio-pathological mechanisms, and strong antiviral therapies developed for HCV infection and HCC, as well as the latest advancements made in the study of the neurological disorders associated with HCV infection.

Hepatitis C virus in people with serious mental illness: An analysis of the care cascade at a tertiary health service with a pilot 'identify and treat' strategy

BACKGROUND

People with serious mental illness (SMI) are underserved from a hepatitis C Virus (HCV) screening and treatment perspective.

AIMS

To examine the HCV care cascade in people with SMI and to pilot a supported HCV treatment integration program.

METHODS

HCV prevalence was retrospectively analysed from 4,492 consecutive individuals admitted to a tertiary hospital mental health service between January 2017 and December 2018. Sub-cohort analysis of screening patterns and predictors of seropositive infection was performed. Referral pathways and community care integration were analysed for HCV positive individuals, and a prospective community-based 'identify and treat' HCV program was assessed.

RESULTS

Screening for HCV had been performed in 18.6% (835/4,492) of the cohort. Seroprevalence was 4.6% (207/4,492). HCV seropositivity was associated with age > 40-years (OR = 9.30, CI 3.69-23.45, p <0.01), injecting drug use (IDU) (OR = 24.26, CI 8.99-65.43, p <0.01), and previous incarceration (OR = 12.26, 4.51-33.31, p <0.01). In a cohort of treatment-eligible individuals, 43.3% (90/208) had neither been referred to specialist services or general practitioners for HCV management. Amongst those referred to specialist services, 64.7% (57/88) did not attend scheduled follow-up, and 48.3% (15/31) of attendees were lost to follow-up. Through an intensified community access program, 10 people were successfully treated for HCV, though 22 could not be engaged.

CONCLUSION

People with SMI are underserved by traditional models of HCV healthcare. Intensified community-based support can partially bolster the treatment cascade, though investment in innovative screening and management strategies are required to achieve healthcare parity. This article is protected by copyright. All rights reserved.

Impact of direct acting antivirals (DAA) on neurologic disorders in chronic hepatitis C

INTRODUCTION

Neurologic and neuropsychiatric manifestations sometimes provide the first evidence of an unknown HCV infection. These conditions develop with a variable ranging of morbidity, including: "brain fog," fatigue, subtle cognitive and attention impairment, but also with more severe complications or acute presentation, like encephalomyelitis, encephalopathy, stroke and peripheral nerves involvement.

EVIDENCE ACQUISITION

We performed a systematic literature search on PubMed, Cochrane Library and Web of Science databases for articles only in English language, that assessed the relationship between "DAA treatment and neurologic disorders" and after the attainment of SVR in full reports of cases that received the DAA schedule from January 2015 to December 2019. The following terms were used: "chronic Hepatitis C," "HCV," "DAA," "direct-acting antiviral," "SVR," "sustained virologic response," peripheral neuropathy" and "neurologic diseases or disorders."

EVIDENCE SYNTHESIS

HCV infection does not only involve the liver, causing cirrhosis and hepatocellular carcinoma (HCC), but also induces extrahepatic manifestations (EHM), mainly due to a complex immune disease, that damage small and medium vessels, called "mixed cryoglobulinemic vasculitis" (MCV). This kind of mechanism generates most of the HCV-induced neurological damages. Since 2015, the availability of direct-acting antiviral (DAA) oral molecules interfering with HCV replication has completely revolutionized therapeutic options and the target population, which now includes patients aged 12 to 80 years and with advanced liver disease. Relevant was the highlighted DAA effectiveness by achievement of a sustained virologic response (SVR) in about 95% of cases, showing a great tolerability.

CONCLUSIONS

This favorable effect has arisen in a wide category of patients infected by HCV, including subjects with cirrhosis and complications and/or with EHM, who showed a significant improvement of their symptoms and the disease regression. In this concise review, we examine the clinical outcomes after the introduction of the DAA for the treatment of chronic hepatitis C (CHC), focusing on the neurologic disorders and concluding that there is a strong amelioration of neurologic conditions in several cases, particularly, after attaining the viral eradication with a favorable course in most treated cases.

The Role of B Cells in Adult and Paediatric Liver Injury

B lymphocytes are multitasking cells that direct the immune response by producing pro- or anti-inflammatory cytokines, by presenting processed antigen for T cell activation and co-stimulation, and by turning into antibody-secreting cells. These functions are important to control infection in the liver but can also exacerbate tissue damage and fibrosis as part of persistent inflammation that can lead to end stage disease requiring a transplant. In transplantation, immunosuppression increases the incidence of lymphoma and often this is of B cell origin. In this review we bring together information on liver B cell biology from different liver diseases, including alcohol-related and metabolic fatty liver disease, autoimmune hepatitis, primary biliary and primary sclerosing cholangitis, viral hepatitis and, in infants, biliary atresia. We also discuss the impact of B cell depletion therapy in the liver setting. Taken together, our analysis shows that B cells are important in the pathogenesis of liver diseases and that further research is necessary to fully characterise the human liver B cell compartment.

Neurological and psychiatric effects of hepatitis C virus infection

Hepatitis C virus (HCV) infection is widespread and affects 71 million people worldwide. Although hepatic manifestations are the most frequent, ranging from chronic hepatitis to cirrhosis and hepatocellular carcinoma, it is also associated with several extrahepatic manifestations. Infected patients may present non-specific neurological symptoms, regardless of the presence of liver cirrhosis. Several pathogenetic mechanisms underlying neurological symptoms have been hypothesized: neuroinvasion, immune-mediated damage, neurotransmitter alterations and cryoglobulinemia. Alterations of the central nervous system include cerebral vasculopathy, acute or subacute encephalopathy and inflammatory disorders. HCV infection may be responsible for neuropathies, of which the most frequent form is symmetrical axonal sensory or sensory-motor polyneuropathy which causes loss of leg sensitivity and weakness. Up to 50% of patients with HCV infection may experience cognitive decline and psychological disorders, such as depression and fatigue. HCV associated neurocognitive disorder is independent of the presence of liver cirrhosis and affects different domains than in patients with hepatic encephalopathy. It can be studied using specific tests that mainly explore executive functions, verbal learning and verbal recall. These disorders significantly reduce the quality of life. The new antiviral therapies improve the extrahepatic symptoms of HCV infection and their success depends on the achievement of sustained virological response. However, the effect of therapy may differ depending on the type of organ involved; neurological symptoms can be irreversible if there is organic liver damage. The aim of this review is to provide a critical overview of physiopathological mechanisms, diagnostic and therapeutic strategies of the neurological and psychiatric effects of HCV infection.

Reconstitution of T follicular helper-humoral immune axis with elimination of hepatitis C virus

Exhaustion of Hepatitis C Virus (HCV)-specific T cells and abnormal B cell function is a hallmark of chronic HCV infection. Direct-acting antiviral (DAA) therapies are effective in achieving sustained virologic response (SVR), however, whether successful DAA treatment reconstitute T follicular helper (T_FH)-B cell axis in HCV patients is unclear. Here, we aimed to evaluate the immunological changes in global and HCV-specific CD4 + CXCR5 + T_FH, CD4 + CXCR5-T and B cells in 20 HCV patients who achieved SVR with Sofosbuvir and Ledipasvir for 12 weeks and compared with 15 healthy controls (HC). Global and HCV-specific CD4 + CXCR5 + T_FH, CD4 + CXCR5-T and CD19 + B cells had significant phenotypic and functional reconstitution post DAA therapy. Reconstitution of effector, central and terminally differentiated memory cell population and increased ICOS and BCL6 expression was seen in HCV patients at SVR12. HCV-specific cytokines were also improved post DAA. Exhausted and regulatory B cells were declined whereas memory B cells were expanded post DAA therapy. Importantly, frequencies of T_FH cells were significantly associated with HCV RNA reduction, expansion of memory B and plasmablasts, while negatively associated with exhausted/regulatory B cells. Our results demonstrate that SVR with DAA therapy is effective in the reconstitution of phenotypic and functional abnormalities of T_FH-B cell axis.

[Neurological complications of hepatitis C infections]

Die chronische Hepatitis-C-Virus(HCV)-Infektion ist eine hochprävalente Systemerkrankung, die verschiedene neurologische Komplikationen verursachen kann. Es lassen sich HCV-assoziierte Symptome im zentralen und peripheren Nervensystem sowie der Muskulatur unterscheiden. Wichtige Pathomechanismen sind die HCV-assoziierte Autoimmunität (z. B. gemischte Kryoglobulinämie mit Polyneuropathie) und direkte Neurotoxizität (z. B. bei HCV-assoziierten kognitiven Defiziten). Die häufigsten neurologischen Komplikationen sind distal-symmetrische Polyneuropathien, Small-fiber-Neuropathien und kognitive Defizite. Die HCV-Infektion stellt außerdem einen Risikofaktor für ischämische und hämorrhagische Schlaganfälle sowie den Morbus Parkinson dar. Die frühe Identifikation und antivirale Behandlung HCV-positiver Patienten steht im Zentrum der Behandlung. Durch neue antivirale Therapien können >90 % der Patienten dauerhaft von der HCV-Infektion geheilt werden.

Sustained virological response to hepatitis C therapy does not decrease the incidence of systemic lupus erythematosus or rheumatoid arthritis

In patients with chronic hepatitis C (CHC), the effects of baseline characteristics, virological profiles, and therapeutic outcome to pegylated interferon plus ribavirin (PR) therapy on autoimmune diseases are unknown. Taiwanese Chronic Hepatitis C Cohort is a nationwide hepatitis C virus registry cohort comprising 23 hospitals of Taiwan. A total of 12,770 CHC patients receiving PR therapy for at least 4 weeks between January 2003 and December 2015 were enrolled and their data were linked to the Taiwan National Health Insurance Research Database for studying the development of 10 autoimmune diseases. The mean follow-up duration was 5.3 ± 2.9 years with a total of 67,930 person-years, and the annual incidence of systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA) was 0.03%. Other autoimmune diseases were not assessable due to few events. Body mass index ≥24 kg/m² was an independent predictor of the low incidence of SLE or RA (hazard ratio 0.40, 95% confidence interval 0.17–0.93, p = 0.034). A sustained virological response (SVR) to PR therapy was not associated with the low incidence of SLE or RA in any subgroup analysis. CHC patients achieving SVR to PR therapy did not exhibit an impact on the incidence of SLE or RA compared with non-SVR patients.

CD5/CD20 expression on circulating B cells in HCV-related chronic hepatitis and mixed cryoglobulinemia

The role of CD5⁺ B cells in patients with HCV infection and HCV-related disorders, including mixed cryoglobulinemia (MC), has been addressed in previous reports with conflicting results. We established a correlation between CD5/CD20 expression on circulating B lymphocytes, characterizing monoclonal B cell lymphocytosis (MBL), and clinical features in a cohort of 45 patients with chronic HCV hepatitis [without MC: 23 patients (MC- group); with MC: 22 patients (MC+ group)], and 45 HCV-negative healthy subjects as controls. By flow cytometry analysis, three B cells phenotypes were singled out: 1) CD5⁺CD20^dim (CLL-like phenotype); 2) CD5⁺CD20^bright (atypical phenotype); and 3) CD5^-CD20⁺ phenotype. CD5⁺CD20^bright cells were reduced in MC- patients (p=0.049). CD5⁺CD20^dim B cells were significantly higher in group B than in the control group (p=0.003). ROC curve analysis in MC+ patients showed the highest positive likelihood ratio at ≥7.35% (p=0.008) for CLL-like phenotype and at ≤63.6% (p=0.03) for the CD5^-CD20⁺ B cell phenotype. HCV infection was associated with a higher frequency of CLL-like (odds ratio=16, p=0.002) and a lower frequency of atypical (odds ratio: 3.1, p=0.02) and CD5^-CD20⁺ (odds ratio: 11, p=0.01) phenotypes. The association with higher levels of CLL-like phenotype progressively increased from group of MC- patients (odds ratio: 9.3, p=0.04) to the group of MC+ patients (odds ratio: 25.1, p=0.0003). CONCLUSIONS: The occurrence of a CLL-like pattern may allow to identify HCV-infected patients at risk of developing MC and eventually non-Hodgkin lymphoma, who should require a closer surveillance and a longer follow-up.

The Complement System and C1q in Chronic Hepatitis C Virus Infection and Mixed Cryoglobulinemia

The complement system bridges innate and adaptive immunity against microbial infections, with viral infection being a major trigger. Activation of the classical, alternative, and lectin pathways have been reported in chronic hepatitis C virus (HCV) infection and/or cryoglobulinemia. HCV infection leads to dysregulation of complement-mediated immune responses. Clinical and experimental evidence support involvement of complement in intra- and extrahepatic manifestations of HCV infection, such as liver fibrosis and type II cryoglobulinemia. In this review, we summarize studies that have investigated the interplay between HCV and the complement system to establish chronic infection and autoimmunity, as well as the association between HCV pathogenesis and abnormal complement profiles. Several unanswered questions are highlighted which suggest additional informative lines of investigation.

Treatment for hepatitis C virus-associated mixed cryoglobulinaemia

BACKGROUND

Hepatitis C virus (HCV)-associated mixed cryoglobulinaemia is the manifestation of an inflammation of small and medium-sized vessels produced by a pathogenic IgM with rheumatoid factor activity generated by an expansion of B-cells. The immune complexes formed precipitate mainly in the skin, joints, kidneys or peripheral nerve fibres. Current therapeutic approaches are aimed at elimination of HCV infection, removal of cryoglobulins and also of the B-cell clonal expansions. The optimal treatment for it has not been established.

OBJECTIVES

This review aims to look at the benefits and harms of the currently available treatment options to treat the HCV-associated mixed cryoglobulinaemia with active manifestations of vasculitis (cutaneous or glomerulonephritis).

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 30 November 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs looking at interventions directed at treatment of HCV-associated cryoglobulinaemic vasculitis (immunosuppressive medications and plasma exchange therapy) have been included.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the retrieved titles and abstracts. Authors of included studies were contacted to obtain missing information. Statistical analyses were performed using random effects models and results expressed as risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI). The planned primary outcomes were kidney disease, skin vasculitis, musculoskeletal symptoms, peripheral joint arthralgia, peripheral neuropathies, liver involvement, interstitial lung involvement, widespread vasculitis and death. Other planned outcomes were: therapy duration, laboratory findings, adverse effects, antiviral therapy failure, B-cell lymphoma, endocrine disorders and costs of treatment.

MAIN RESULTS

Ten studies were included in the review (394 participants). None of them evaluated direct-acting antivirals. Seven studies were single-centre studies and three were multicentre. The duration of the studies varied from six to 36 months. The risk of bias was generally unclear or low. Three different interventions were examined: use of rituximab (3 studies, 118 participants); interferon (IFN) (IFN compared to other strategies (5 studies, 223 participants); six IFN months versus one year (1 study, 36 participants), and immunoadsorption apheresis versus only immunosuppressive therapy (1 study, 17 participants).The use of rituximab may slightly improve skin vasculitis (2 studies, 78 participants: RR 0.57, 95% CI 0.28 to 1.16; moderate certainty evidence) and made little of no difference to kidney disease (moderate certainty evidence). In terms of laboratory data, the effect of rituximab was uncertain for cryocrit (MD -2.01%, 95% CI -10.29% to 6.27%, low certainty evidence) and HCV replication. Rituximab may slightly increase infusion reactions compared to immunosuppressive medication (3 studies, 118 participants: RR 4.33, 95%CI 0.76 to 24.75, moderate certainty evidence) however discontinuations of the treatment due to adverse reactions were similar (3 studies, 118 participants: RR 0.97, 95% CI 0.22 to 4.36, moderate certainty evidence).Effects of lFN on clinical symptoms were evaluated only in narrative results. When laboratory parameters were assessed, IFN made little or no difference in levels of alanine transaminase (ALT) at six months (2 studies, 39 participants: MD -5.89 UI/L, 95%CI -55.77 to 43.99); rheumatoid factor activity at six months (1 study, 13 participants: MD 97.00 UI/mL, 95%CI -187.37 to 381.37), or C4 levels at 18 months (2 studies, 49 participants: MD -0.04 mg/dL, 95%CI -2.74 to 2.67). On the other hand, at 18 months IFN may probably decrease ALT (2 studies, 39 participants: MD -28.28 UI/L, 95%CI -48.03 to -8.54) and Ig M (-595.75 mg/dL, 95%CI -877.2 to -314.3), but all with low certainty evidence. One study reported infusion reactions may be higher in IFN group compared to immunosuppressive therapy (RR 27.82, 95%CI 1.72 to 449.18), and IFN may lead to higher discontinuations of the treatment due to adverse reactions (4 studies, 148 participants: RR 2.32, 95%CI 0.91 to 5.90) with low certainty evidence. Interferon therapy probably improved skin vasculitis (3 studies, 95 participants: RR 0.60, 95% CI 0.36 to 1.00) and proteinuria (2 studies, 49 participants: MD -1.98 g/24 h, 95% CI -2.89 to -1.07), without changing serum creatinine at 18 months (2 studies, 49 participants: MD -30.32 μmol/L, 95%CI -80.59 to 19.95).Six months versus one year treatment with IFN resulted in differences terms of the maintenance of the response, 89% of patients in the six months group presented a relapse and only 11% maintained a long-term response at one year, while in the one year group only 78% relapsed and long-term response was observed in 22%. The one-year therapy was linked to a higher number of side-effects (severe enough to cause the discontinuation of treatment in two cases) than the six-month schedule.One study reported immunoadsorption apheresis had uncertain effects on skin vasculitis (RR 0.44, 95% CI 0.05 to 4.02), peripheral neuropathies (RR 2.70, 95%CI 0.13 to 58.24), and peripheral joint arthralgia (RR 2.70, 95%CI 0.13 to 58.24), cryocrit (MD 0.01%, 95%CI -1.86 to 1.88) at six months, and no infusion reactions were reported. However when clinical scores were evaluated, they reported changes were more favourable in immunoadsorption apheresis with higher remission of severe clinical complications (80% versus 33%, P = 0.05) compared to immunosuppressive treatment alone.In terms of death, it was not possible to present a pooled intervention effect estimate because most of the studies reported no deaths, or did not report death as an outcome.

AUTHORS' CONCLUSIONS

To treat HCV-associated mixed cryoglobulinaemia, it may be beneficial to eliminate HCV infection by using antiviral treatment and to stop the immune response by using rituximab. For skin vasculitis and for some laboratory findings, it may be appropriate to combine antiviral treatment with deletion of B-cell clonal expansions by using of rituximab. The applicability of evidence reviewed here is limited by the absence of any studies with direct-acting antivirals, which are urgently needed to guide therapy.

Direct-acting antiviral agents in the therapy of hepatitis C virus-related mixed cryoglobulinaemia: a single-centre experience

BACKGROUND

The efficacy and safety of direct-acting antiviral agents (DAAs) were evaluated in a cohort of prospectively enrolled patients with hepatitis C virus (HCV)-related mixed cryoglobulinaemia (MC), an immune complex-mediated vasculitis of small and medium vessels in which the pathogenetic role of HCV has been clearly established.

METHODS

Twenty-two patients received DAAs. Clinical and laboratory features were recorded at baseline, every 4 weeks until the end of treatment (EoT), and 12 weeks afterwards. Primary efficacy endpoints were (a) sustained virological response 12 weeks after therapy completion (SVR12), (b) regression of symptomatology (clinical response) and (c) cryoglobulin disappearance or cryocrit reduction ≥50% (immunological response). Complete response (CR) was defined as the occurrence of all three primary endpoints; partial response (PR) was defined as the occurrence of SVR12, with or without either immunological or clinical response; and no response was defined as missing the achievement of all three endpoints.

RESULTS

All patients reached SVR12. Compared with basal values, mean cryocrit values were significantly decreased at EoT and SVR12. A significant reduction of alanine transaminase and a parallel increase of complement component C4 levels were also detected. Rheumatoid factor activity was significantly reduced at EoT but not at SVR12. At SVR12, a CR was established in 14 patients (63.7%) and a PR in 8 patients (36.3%). In one patient with small lymphocytic lymphoma, the tumour progressed despite viral clearance. Mild adverse events were recorded in nine patients (40.9%).

CONCLUSIONS

The response rates induced by the use of DAAs in patients with MC were remarkably higher than those previously achieved with pegylated interferon-α/ribavirin, with or without rituximab. A much longer follow-up is desirable to achieve useful information in terms of persistent viral clearance and clinical response.

A pre-neoplastic epigenetic field defect in HCV-infected liver at transcription factor binding sites and polycomb targets

The predisposition of patients with Hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) involves components of viral infection, inflammation and time. The development of multifocal, genetically distinct tumours is suggestive of a field defect affecting the entire liver. The molecular susceptibility mediating such a field defect is not understood. One potential mediator of long-term cellular reprogramming is heritable (epigenetic) regulation of transcription, exemplified by DNA methylation. We studied epigenetic and transcriptional changes in HCV-infected livers in comparison with control, uninfected livers and HCC, allowing us to identify pre-neoplastic epigenetic and transcriptional events. We find the HCV-infected liver to have a pattern of acquisition of DNA methylation targeted to candidate enhancers active in liver cells, enriched for the binding sites of the FOXA1, FOXA2 and HNF4A transcription factors. These enhancers can be subdivided into those proximal to genes implicated in liver cancer or to genes involved in stem cell development, the latter distinguished by increased CG dinucleotide density and polycomb-mediated repression, manifested by the additional acquisition of histone H3 lysine 27 trimethylation (H3K27me3). Transcriptional studies on our samples showed that the increased DNA methylation at enhancers was associated with decreased local gene expression, results validated in independent samples from The Cancer Genome Atlas. Pharmacological depletion of H3K27me3 using the EZH2 inhibitor GSK343 in HepG2 cells suppressed cell growth and also revealed that local acquired DNA methylation was not dependent upon the presence of polycomb-mediated repression. The results support a model of HCV infection influencing the binding of transcription factors to cognate sites in the genome, with consequent local acquisition of DNA methylation, and the added repressive influence of polycomb at a subset of CG-dense cis-regulatory sequences. These epigenetic events occur before neoplastic transformation, resulting in what may be a pharmacologically reversible epigenetic field defect in HCV-infected liver.

Lack of Any Relationship Between Circulating Autoantibodies and Interleukin–6 Levels in Egyptian Patients Infected with the Hepatitis C Virus

Introduction: Elevated serum interleukin (IL) 6 has been reported in patients infected with the hepatitis C virus (HCV), but it remains debatable whether this influences the production of autoantibodies and the biochemical profile of HCV disease. Therefore, this current study was conducted to evaluate the relationship between IL-6 and circulating autoantibody levels in HCV positive patients. Methods: Levels of IL-6 in serum samples from 102 patients with HCV and 103 normal controls were determined by enzyme linked immunosorbent assay (ELISA). Autoantibodies were detected by immunofluorescence. Results: Levels of IL-6 were significantly higher (p=0.028) in patients infected with (HCV) compared with normal group. Autoantibodies were noted in in 43.1% of the patients; of these, 23.5% featured anti-nuclear antibodies (ANA+), 16.7% anti-smooth muscle antibodies (ASMA+), 7.8% anti-mitochondrial antibodies (AMA+), 17.6% anti-parietal cell antibodies (APCA+), 7.8% anti canalicular antibodies, and 2.9% anti reticulin antibodies (ARA+). No patients were found to be positive for anti-brush border antibodies (ABBA) or anti-ribosomal antibodies. (ARiA). No links with IL-6 levels were apparent. Conclusions: IL-6 levels are increased in patients infected with HCV disease and could influence the production of autoantibodies. However, this study did not provide evidence of a specific relationship between IL6 and circulating autoantibodies in such cases.

CB2-63 polymorphism and immune-mediated diseases associated with HCV chronic infection

AIMS

To evaluate whether CB2 variants are associated with the presence of immune-mediated disorders (IMDs) in patients with chronic HCV infection.

METHODS

One hundred and sixty-eight anti-HCV/HCV-RNA-positive patients were enrolled, 81 with signs of IMDs and 87 without. In the IMDs group, 22 (27.2%) showed ANA positivity (titers ≥1:160), 3 (3.7%) SMA positivity (titers ≥1:160), 24 (29.6%) had cryoglobulinemia, 25 (30.9%) autoimmune thyroiditis, 4 (4.9%) psoriasis, 2 (2.5%) B-cell non-Hodgkin lymphoma and 1 (1.2%) autoimmune hemolytic anemia. All patients were screened for the CNR2 rs35761398 single nucleotide polymorphism using a TaqMan Assay.

RESULTS

Compared with the 87 patients without IMDs, the 81 with IMDs were more frequently females (65% vs. 45%, p=0.01), but no significant difference was found in the initial demographic, epidemiological, serological, biochemical or virological data. Instead, the prevalence of patients with the CB2-63 RR variant was significantly higher in the IMD than in the non-IMD group (49.4% vs. 24.1%, p=0.001). A logistic regression analysis including the CB2-63 receptor (RR vs. QR or QQ), age and sex identified the CB2-63 RR as the only independent predictor of IMDs (p=0.005).

CONCLUSIONS

The data suggest a significant, previously unknown, independent association between the CB2-63 RR variant and IMDs in anti-HCV-positive patients. The study was approved by the Ethics Committee of the Azienda Ospedaliera Universitaria of the Second University of Naples (n° 214/2012).

Differential expression of viral agents in lymphoma tissues of patients with ABC diffuse large B-cell lymphoma from high and low endemic infectious disease regions

Diffuse large B-cell lymphoma (DLBCL), the most common type of non-Hodgkin's lymphoma (NHL) in adults, accounts for approximately 30-40% of newly diagnosed lymphomas worldwide. Environmental factors, such as viruses and bacteria, may contribute to cancer development through chronic inflammation and the integration of oncogenes, and have previously been indicated in cervical cancer, hepatocellular carcinoma, gastric cancer and lymphoproliferative disorders. In the present study, the presence of microbial agents was analyzed in the lymphoma tissue of patients with activated B-cell like (ABC) DLBCL. The present study compared two groups of patients from geographically varied regions that possess a difference in the prevalence of viral and other microbial agents. The patient populations were from Sweden (a low endemic infectious disease region) and Egypt (a high endemic infectious disease region). A differential expression of several viruses in lymphoma tissues was noted when comparing Swedish and Egyptian patients. JC polyomavirus (JCV) was detected in Swedish and Egyptian patients and, uniquely, the complete hepatitis B virus (HBV) genome was detected only in Egyptian lymphoma patients. None of these viruses were detected in control lymph tissues from Sweden or Egypt. In total, 38% of the Egyptian patients were found to have HBV surface antigens (HBsAgs) in their serum; however, HBsAgs were not found in any of the Swedish patients. The percentage of serum HBsAgs in Egyptian patients with ABC DLBCL was significantly increased compared with the general Egyptian population (P<0.05). The present study may support a notion that viral agents, including JCV and HBV, may be involved in the tumorigenesis of DLBCL in regions of high infectious disease.

Host Cell Targets in HCV Therapy: Novel Strategy or Proven Practice?

The development of novel antiviral drugs against hepatitis C is a challenging and competitive area of research. Progress of this research has been hampered due to the quasispecies nature of the hepatitis C virus, the absence of cellular infection models and the lack of easily accessible and highly representative animal models. The current combination therapy consisting of interferon-α and ribavirin mainly acts by supporting host cell defence. These therapeutics are the prototypic representatives of indirect antiviral agents as they act on cellular targets. However, the therapy is not a cure, when considered from the long-term perspective, for almost half of the chronically infected patients. This draws attention to the urgent need for more efficient treatments. Novel anti-hepatitis C treatments under study are directed against a number of so-called direct antiviral targets such as polymerases and proteases, which are encoded by the virus. Although such direct antiviral approaches have proven to be successful in several viral indications, there is a risk of resistant viruses developing. In order to avoid resistance, the development of indirect antiviral compounds has to be intensified. These act on host cell targets either by boosting the immune response or by blocking the virus host cell interaction. A particularly interesting approach is the development of inhibitors that interfere with signal transduction, such as protein kinase inhibitors. The purpose of this review is to stress the importance of developing indirect antiviral agents that act on host cell targets. In doing so, a large source of potential targets and mechanisms can be exploited, thus increasing the likelihood of success. Ultimately, combination therapies consisting of drugs against direct and indirect viral targets will most probably provide the solution to fighting and eradicating hepatitis C virus in patients.

Extrahepatic Manifestations of Hepatitis C Virus

Chronic infection with the hepatitis C virus (HCV) is a major cause of liver disease worldwide and is also responsible for extrahepatic manifestations (EHMs) involving the skin, kidneys, salivary glands, eyes, thyroid, and immune system. Mixed cryoglobulinemia is the prototype EHM related to HCV infection. Although these HCV-related EHMs may contribute to significant rates of morbidity affecting patient's quality of life and survival, most of these complications can reverse after HCV eradication by interferon therapy. This notwithstanding, individual patients may have an irreversible injury in various organs that is not reversed by a cure of the HCV infection.

Pre-stimulation of CD81 expression by resting B cells increases proliferation following EBV infection, but the overexpression of CD81 induces the apoptosis of EBV-transformed B cells

Hepatitis C virus (HCV) E2 protein binds to CD81, which is a component of the B cell co-stimulatory complex. The E2-CD81 interaction leads to B cell proliferation, protein tyrosine phosphorylation and to the hypermutation of immunoglobulin genes. Epidemiological studies have reported a high prevalence of B cell non-Hodgkin lymphoma (NHL) in HCV-positive patients, suggesting a potential association between HCV and Epstein-Barr virus (EBV) in the genesis of B lymphocyte proliferative disorders. In the present study, in order to investigate the association between EBV and HCV in B cells, we created an in vitro EBV-induced B cell transformation model. CD81 was gradually overexpressed during transformation by EBV. B cells isolated from HCV-positive patients grew more rapidly and clumped together earlier than B cells isolated from healthy donors following EBV infection. Pre-stimulation of CD81 expressed by resting B cells with anti-CD81 monoclonal antibody (mAb) or HCV E2 accelerated the generation of lymphoblastoid cell lines (LCLs) by EBV infection. These cells proliferated prominently through the early expression of interleukin-10 and intracellular latent membrane protein (LMP)-l. By contrast, the overexpression of CD81 on EBV-transformed B cells by anti-CD81 mAb or HCV E2 protein induced apoptosis through reactive oxygen species (ROS)-mediated mitochondrial dysfunction. These results suggest that the engagement of CD81 expressed by B cells has differential effects on B cell fate (proliferation or apoptosis) according to EBV infection and the expression level of CD81.

Pathogenesis of Myeloproliferative Neoplasms: Role and Mechanisms of Chronic Inflammation

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of clonal diseases characterized by the excessive and chronic production of mature cells from one or several of the myeloid lineages. Recent advances in the biology of MPNs have greatly facilitated their molecular diagnosis since most patients present with mutation(s) in the JAK2, MPL, or CALR genes. Yet the roles played by these mutations in the pathogenesis and main complications of the different subtypes of MPNs are not fully elucidated. Importantly, chronic inflammation has long been associated with MPN disease and some of the symptoms and complications can be linked to inflammation. Moreover, the JAK inhibitor clinical trials showed that the reduction of symptoms linked to inflammation was beneficial to patients even in the absence of significant decrease in the JAK2-V617F mutant load. These observations suggested that part of the inflammation observed in patients with JAK2-mutated MPNs may not be the consequence of JAK2 mutation. The aim of this paper is to review the different aspects of inflammation in MPNs, the molecular mechanisms involved, the role of specific genetic defects, and the evidence that increased production of certain cytokines depends or not on MPN-associated mutations, and to discuss possible nongenetic causes of inflammation.

Activation-induced cytidine deaminase in B cells of hepatits C virus-related cryoglobulinaemic vasculitis

Immunoglobulin variable region heavy chain (IgVH ) somatic gene diversification is instrumental in the transformation process that characterizes hepatitis C virus (HCV)-related B cell lymphoproliferative disorders. However, the extent to which activation-induced cytidine deaminase (AID), an enzyme essential for IgV gene somatic hypermutation (SHM), is active in cryoglobulinaemic vasculitis (CV) remains unclear. AID mRNA expression in the peripheral blood of 102 chronically hepatitis C virus (HCV)-infected patients (58 with and 44 without CV) and 26 healthy subjects was investigated using real-time reverse transcription-polymerase chain reaction (RT-PCR). The features of activation-induced cytidine deaminase (AID) protein and mRNA transcripts were explored in liver tissue biopsies and portal tracts isolated using laser capture microdissection. In chronically HCV-infected patients, AID mRNA expression was almost threefold higher in those with than in those without CV and sevenfold higher than in healthy subjects (median-fold: 6.68 versus 2.54, P = 0.03 and versus 0.95, P = 0.0003). AID transcript levels were significantly higher in polyclonal than in clonally restricted B cell preparations in either CV or non-CV patients (median-fold, 15.0 versus 2.70, P = 0.009 and 3.46 versus 1.58, P = 0.02, respectively). AID gene expression was found to be related negatively to age and virological parameters. AID protein was found in portal tracts containing inflammatory cells that, in several instances, expressed AID mRNA transcripts. Our data indicate that the aberrant expression of AID may reflect continuous B cell activation and sustained survival signals in HCV-related CV patients.

Virus-driven autoimmunity and lymphoproliferation: the example of HCV infection

HCV chronic infection is characterized by possible development of both hepatic and extrahepatic manifestations. The infection by this both hepatotropic and lymphotropic virus is responsible for polyoligoclonal B-lymphocyte expansion, leading to several immune-mediated disorders. Mixed cryoglobulinemia syndrome that in some cases may evolve to frank B-cell non-Hodgkin's lymphoma is the prototype of HCV-driven autoimmune and lymphoproliferative disorders. The HCV oncogenic potential has been suggested by several clinicoepidemiological and laboratory studies; it includes hepatocellular carcinoma, B-cell non-Hodgkin's lymphoma and papillary thyroid cancer. The definition HCV syndrome refers to the complex of HCV-driven diseases; these latter are characterized by heterogeneous geographical distribution, suggesting a role of other important genetic and/or environmental cofactors. The natural history of HCV syndrome is the result of a multifactorial and multistep pathogenetic process, which may evolve from mild manifestations to systemic autoimmune disorders, and less frequently to malignant neoplasias. The present updated review analyzes the clinical and pathogenetic aspects of the main HCV-associated diseases.

Hepatitis C virus syndrome: A constellation of organ- and non-organ specific autoimmune disorders, B-cell non-Hodgkin's lymphoma, and cancer

The clinical course of chronic hepatitis C virus (HCV) infection is characterized by possible development of both liver and extrahepatic disorders. The tropism of HCV for the lymphoid tissue is responsible for several immune-mediated disorders; a poly-oligoclonal B-lymphocyte expansion, commonly observed in a high proportion of patients with HCV infection, are responsible for the production of different autoantibodies and immune-complexes, such as mixed cryoglobulins. These serological alterations may characterize a variety of autoimmune or neoplastic diseases. Cryoglobulinemic vasculitis due to small-vessel deposition of circulating mixed cryoglobulins is the prototype of HCV-driven immune-mediated and lymphoproliferative disorders; interestingly, in some cases the disease may evolve to frank malignant lymphoma. In addition, HCV shows an oncogenic potential as suggested by several clinico-epidemiological and laboratory studies; in addition to hepatocellular carcinoma that represents the most frequent HCV-related malignancy, a causative role of HCV has been largely demonstrated in a significant percentage of patients with isolated B-cells non-Hodgkin's lymphomas. The same virus may be also involved in the pathogenesis of papillary thyroid cancer, a rare neoplastic condition that may complicate HCV-related thyroid involvement. Patients with HCV infection are frequently asymptomatic or may develop only hepatic alteration, while a limited but clinically relevant number can develop one or more autoimmune and/or neoplastic disorders. Given the large variability of their prevalence among patients' populations from different countries, it is possible to hypothesize a potential role of other co-factors, i.e., genetic and/or environmental, in the pathogenesis of HCV-related extra-hepatic diseases.

Waldenström macroglobulinemia in hepatitis C: case report and review of the current literature

Background. Recent literature has associated hepatitis C virus with the development of non-Hodgkin lymphoma. Hepatitis C virus infection appears to promote lymphoproliferation, providing a plausible mechanism for a causative association; however, despite prior reports of patients with comorbid hepatitis C infection and Waldenström macroglobulinemia, the literature is in disagreement regarding whether there exists an association between these two conditions. Case Presentation. This case report describes a 57-year-old African-American male with chronic hepatitis C infection and cryoglobulinemia who presented with several episodes of transient confusion and paralysis and was found to have symptomatic hyperviscosity. The recognition of his condition was facilitated by characteristic findings on ophthalmologic examination. He was subsequently diagnosed with Waldenström macroglobulinemia on bone marrow biopsy. Conclusions. An up to date, comprehensive review of the literature suggests an association between hepatitis C and Waldenström macroglobulinemia. Data on optimal treatment of patients with comorbid hepatitis C infection and Waldenström macroglobulinemia is limited. We have provided a comprehensive review of previously explored treatment options to guide management of other similar patients. Our patient has since been treated with repeated plasmapheresis with a plan to pursue antiviral therapy.

Hepatitis C virus reactivation in cancer patients in the era of targeted therapies

The purpose of this review is to summarize the evidence of hepatitis C reactivation in cancer patients in the era of targeted therapies. Targeted therapies are novel therapeutics frequently used in cancer patients. During treatment with targeted therapies, viral replication is one of the major problems that can occur. The PubMed database, ASCO, and ASCO Gastrointestinal Cancer Symposium abstracts were searched up until September 15, 2013 using the following search keywords: “targeted therapies, rituximab, alemtuzumab, brentuximab, hepatitis, hepatitis C reactivation, tyrosine kinase inhibitors, imatinib, mammalian target of rapamycin (mTOR) inhibitors, everolimus, anti-HER therapies, trastuzumab, pertuzumab, lapatinib, anti-epidermal growth factor receptor therapies, cetuximab, panitumumab, and ipilimumab”. Papers considered relevant for the aim of this review were selected by the authors. The data about rituximab-induced hepatic flare in hepatitis C virus (HCV) positive patients is controversial. However, there is the possibility of life-threatening hepatic flare that can develop after HCV ribonucleic acid (HCV-RNA) viral load increases. Routine follow-up of liver function tests should be advised. Especially in high-risk patients, such as those with baseline chronic active hepatitis and cirrhosis, and where there are plans to administer rituximab concomitantly with corticosteroids, it is advised to have close follow-up of HCV viral load. The data is insufficient to make accurate statements about the association of alemtuzumab therapy and HCV reactivation. However, alemtuzumab may cause deep immunosuppression. Due to this, it is better to follow up with liver function tests and HCV RNA levels during alemtuzumab therapy. Brentuximab has effects on antibody dependent cellular toxicity and may decrease humoral immunity. Thus, we believe that during brentuximab treatment of HCV infected patients, clinicians may encounter hepatitis C reactivation. There have been no reported cases of hepatitis C reactivation with imatinib therapy. However, there are many reports of hepatitis B reactivation with imatinib treatment. Based on the evidence of hepatitis B reactivation with imatinib and the effects of imatinib on immune system functions, we suggest that imatinib therapy might be a risk factor for HCV reactivation. Anti-human epidermal growth factor receptor 2 therapies are not associated with hepatic flare in HCV infected patients. Post-transplant studies reported that mTOR was safely administered to patients with active hepatitis C without causing hepatic flare. Cetuximab and panitumumab have not been associated with HCV reactivation. Two cases of HCV infected melanoma were safely treated with ipilimumab without any HCV reactivation or hepatic flare. Targeted therapies are a new and emerging area of oncology treatment modalities. While treating HCV infected cancer patients, clinicians should be mindful of the immunosuppressive properties of targeted therapies. Further randomized trials are needed to establish algorithms for this issue.

B-cell-intrinsic hepatitis C virus expression leads to B-cell-lymphomagenesis and induction of NF-κB signalling

Hepatitis C virus (HCV) infection leads to the development of hepatic diseases, as well as extrahepatic disorders such as B-cell non-Hodgkin's lymphoma (B-NHL). To reveal the molecular signalling pathways responsible for HCV-associated B-NHL development, we utilised transgenic (Tg) mice that express the full-length HCV genome specifically in B cells and develop non-Hodgkin type B-cell lymphomas (BCLs). The gene expression profiles in B cells from BCL-developing HCV-Tg mice, from BCL-non-developing HCV-Tg mice, and from BCL-non-developing HCV-negative mice were analysed by genome-wide microarray. In BCLs from HCV-Tg mice, the expression of various genes was modified, and for some genes, expression was influenced by the gender of the animals. Markedly modified genes such as Fos, C3, LTβR, A20, NF-κB and miR-26b in BCLs were further characterised using specific assays. We propose that activation of both canonical and alternative NF-κB signalling pathways and down-regulation of miR-26b contribute to the development of HCV-associated B-NHL.

Assessment of total hepatitis C virus (HCV) core protein in HCV-related mixed cryoglobulinemia

Introduction

In hepatitis C virus (HCV)-related mixed cryoglobulinemia (MCG), the nonenveloped HCV core protein (HCV-Cp) is a constituent of the characteristic cold-precipitating immune complexes (ICs). A possible correlation between HCV-Cp, virologic, laboratory, and clinical parameters in both untreated MCG patients and those undergoing specific treatment was explored.

Methods

HCV-Cp was quantified by a fully automated immune assay. Correlations between HCV-Cp and HCV RNA, cryocrit, and virus genotype (gt) were investigated in 102 chronically HCV-infected MCG patients.

Results

HCV-Cp concentrations strongly correlated with HCV RNA levels in baseline samples. An average ratio of 1,425 IU and 12,850 IU HCV RNA per picogram HCV-Cp was estimated in HCV gt-1 and gt-2 patients, respectively. This equation allowed us to estimate that, on average, HCV-Cp was associated with the viral genome in only 3.4% of the former and in 35% of the latter group of patients. The direct relation between HCV-Cp and the cryocrit level suggests that the protein directly influences the amount of cryoprecipitate. Although the therapy with rituximab (RTX) as a single agent resulted in the enhancement of HCV-Cp levels, in patients treated with RTX in combination with a specific antiviral therapy (pegylated interferon-α plus ribavirin), the prompt and effective clearance of HCV-Cp was documented.

Conclusions

Our data provide evidence that HCV-Cp has a direct effect on the cold-precipitation process in a virus genotype-dependence in HCV-related MCG patients.

Interleukin 28B gene polymorphisms in hepatitis C virus-related cryoglobulinemic vasculitis

OBJECTIVE

Single-nucleotide polymorphisms (SNP) in the interleukin 28B (IL-28B) gene region are strongly predictive of the response of infected patients to antiviral therapy for hepatitis C virus (HCV). We sought to determine the prevalence of SNP IL-28B rs12979860 C/C and non-C/C (C/T plus T/T) genotypes in HCV-related cryoglobulinemic vasculitis (CV), as compared with HCV-positive patients without CV. We also searched for their association with peculiar clinical manifestations of CV and potential influence on the complete response (virological, molecular, and immunological) to the therapy.

METHODS

The study cohort comprised 159 and 172 HCV-infected patients with and without CV, respectively, prospectively followed starting from 1990. SNP rs12979860 genotyping was performed by Taq-Man allelic discrimination. In 106 patients (66.6%) with CV, the profile of circulating B cell clonalities was determined as well. All patients with CV were treated with pegylated interferon-α/ribavirin-based antiviral therapy.

RESULTS

The T/T IL-28B genotype was more common in patients with CV than in those without (17% vs 8.1%, p = 0.02). In patients with CV, compared with non-C/C variants, the IL-28B C/C genotype was associated with a higher rate of complete response (52.6% vs 39.2%, p = 0.13), whereas a treatment response of 61.4% was demonstrated when solely virological response was considered (p = 0.008). A higher frequency of expanded B cell clonalities in the circulation (84.2% vs 55.9%; p = 0.005), kidney involvement (21% vs 2.9%; p = 0.003), and B cell non-Hodgkin lymphoma (17.5% vs 6.8%; p = 0.048), were also observed.

CONCLUSION

In HCV-positive patients with CV, the IL-28B C/C genotype is distinguished biologically by a higher frequency of restriction of B cell response and clinically by a higher risk of cryoglobulinemic nephropathy and B cell malignancies, while acting as an independent predictor of a sustained virological response to antiviral therapy. In addition, we found that IL-28B T/T variant was more prevalent in patients with CV than in those without.

Molecular cell biology and immunobiology of mammalian rod/ring structures

Nucleotide biosynthesis is a highly regulated process necessary for cell growth and replication. Cytoplasmic structures in mammalian cells, provisionally described as rods and rings (RR), were identified by human autoantibodies and recently shown to include two key enzymes of the CTP/GTP biosynthetic pathways, cytidine triphosphate synthetase (CTPS) and inosine monophosphate dehydrogenase (IMPDH). Several studies have described CTPS filaments in mammalian cells, Drosophila, yeast, and bacteria. Other studies have identified IMPDH filaments in mammalian cells. Similarities among these studies point to a common evolutionarily conserved cytoplasmic structure composed of a subset of nucleotide biosynthetic enzymes. These structures appear to be a conserved metabolic response to decreased intracellular GTP and/or CTP pools. Antibodies to RR were found to develop in some hepatitis C patients treated with interferon-α and ribavirin. Additionally, the presence of anti-RR antibodies was correlated with poor treatment outcome.

Liver immunology

The liver is the largest organ in the body and is generally regarded by nonimmunologists as having little or no lymphoid function. However, such is far from accurate. This review highlights the importance of the liver as a lymphoid organ. Firstly, we discuss experimental data surrounding the role of liver as a lymphoid organ. The liver facilitates tolerance rather than immunoreactivity, which protects the host from antigenic overload of dietary components and drugs derived from the gut and it is instrumental to fetal immune tolerance. Loss of liver tolerance leads to autoaggressive phenomena, which if not controlled by regulatory lymphoid populations, may lead to the induction of autoimmune liver diseases. Liver-related lymphoid subpopulations also act as critical antigen-presenting cells. The study of the immunological properties of liver and delineation of the microenvironment of the intrahepatic milieu in normal and diseased livers provides a platform to understand the hierarchy of a series of detrimental events that lead to immune-mediated destruction of the liver and the rejection of liver allografts. The majority of emphasis within this review will be on the normal mononuclear cell composition of the liver. However, within this context, we will discuss selected, but not all, immune-mediated liver disease and attempt to place these data in the context of human autoimmunity.

Hepatitis C virus (HCV) infection of peripheral blood mononuclear cells in patients with type II cryoglobulinemia

OBJECTIVES

Type II cryoglobulinemia is a common extrahepatic manifestation of chronic hepatitis C virus (HCV) infection. The mechanisms behind its development are unclear, but could be related to direct infection of the immune cells.

METHODS

Peripheral blood mononuclear cells from 18 patients with type II cryoglobulinemia were separated into CD3+ (T cells), CD19+ (B cells) and CD14+ (monocytes) and analyzed for the presence of negative strand HCV RNA, which is a viral replicative intermediate, and for the presence of HCV non-structural protein 3 (NS3). Control group consisted of 182 consecutive chronic hepatitis C patients prior to initiation of antiviral therapy.

RESULTS

Negative strand HCV RNA was detected in PBMC from six (33.3%), patients and in 15 (8.2%) controls (p < 0.01). Negative strand was most frequently detected in B cells (3 patients), followed by T cells (2 patients), and monocytes (2 patients). One patient was positive both in CD3+ and CD14+ cells. NS3 protein was detected in six (33.3%) patients; five were positive in T cells, three in B cells, and another three were positive in monocytes. Two patients were positive in all analyzed cell subpopulation and one patient was positive in CD14+ and CD19+ cells, but not in CD3+ cells. Altogether, 11 patients (61.1%) were positive either for the negative strand HCV RNA or NS3 protein in at least one of the analyzed cell compartments.

CONCLUSION

Our findings of common presence of viral replication in cells of the immune system suggest that direct HCV infection could play a role in the etiology of cryoglobulinemia.

Malignant lymphoma in primary Sjögren's syndrome: an update on the pathogenesis and treatment

OBJECTIVES

Sjögren's syndrome (SS), a chronic autoimmune disorder, particularly compromises the function of exocrine glands. Its association with lymphoma is well documented. Our aim was to systematically review the molecular, clinical, histopathologic, and therapeutic aspects of these SS-related malignant lymphoproliferations.

METHODS

The literature was searched for original articles published between 1968 and 2012 focusing on the risk factors for lymphoma development in Sjögren's syndrome using MEDLINE and PubMed. The search terms we used were "Sjögren's syndrome," "lymphoma," and "risk factors." All papers identified were English-language, full-text papers.

RESULTS

A low-grade marginal-zone lymphoma related to mucosa-associated lymphoid tissue is the commonest lymphoid neoplasia in SS. The majority of SS-associated lymphomas are characterized by localized stage, indolent clinical course, and recurrence in other extranodal sites. Although the transition from a chronic inflammatory condition to malignant lymphoma is a multistep process that is yet poorly understood, there is increasing evidence that chronic antigenic stimulation by an exoantigen or autoantigens plays an essential role in the development of SS-associated lymphoproliferation.

CONCLUSIONS

This review discusses the pathogenetic aspects of lymphomagenesis in SS. Recent advances in the treatment of lymphoma in SS are also stated.

T cell receptor variable β gene repertoire in liver and peripheral blood lymphocytes of chronically hepatitis C virus-infected patients with and without mixed cryoglobulinaemia

To characterize the repertoire of T lymphocytes in chronically hepatitis C virus (HCV)-infected patients with and without mixed cryoglobulinaemia (MC). T cell receptor (TCR) variable (V) β clonalities in portal tracts isolated from liver biopsy sections with a laser capture microdissection technique in 30 HCV-positive MC patients were studied by size spectratyping. Complementarity-determining region 3 (CDR3) profiles of liver-infiltrating lymphocytes (LIL) were also compared with those circulating in the blood. The representative results of TCR Vβ by CDR3 were also obtained from liver tissues and peripheral blood lymphocytes (PBL) of 21 chronically HCV-infected patients without MC. LIL were highly restricted, with evidence of TCR Vβ clonotypic expansions in 23 of 30 (77%) and in 15 of 21 (71%) MC and non-MC patients, respectively. The blood compartment contained TCR Vβ expanded clones in 19 (63%) MC and 12 (57%) non-MC patients. The occurrence of LIL clonalities was detected irrespective of the degree of liver damage or circulating viral load, whereas it correlated positively with higher levels of intrahepatic HCV RNA. These results support the notion that TCR Vβ repertoire is clonally expanded in HCV-related MC with features comparable to those found in chronically HCV-infected patients without MC.

B cell activating factor (BAFF) in the natural history of chronic hepatitis C virus liver disease and mixed cryoglobulinaemia

B cell activating factor (BAFF) plays a crucial role in the process of development, maturation and activation of B lymphocytes. Chronic hepatitis C virus (HCV) infection is characterized by multiple B cell disorders. It is a major cause of type II mixed cryoglobulinaemia (MC). We measured serum BAFF levels in several clinical situations to elucidate the potential role of BAFF in chronic HCV infection. We used a commercially available solid phase enzyme-linked immunosorbent assay. We estimated serum BAFF in stored sera from uninfected controls (n = 8), patients with chronic hepatitis B virus infection HBV (n = 5) and chronic HCV infection with (n = 16) and without mixed cryoglobulinaemia (n = 14). In two patients with HCV and MC we correlated BAFF with HCV RNA after pegylated interferon (peg-I). We correlated serum BAFF levels at baseline and at 12 weeks with treatment response: sustained virological response SVR (n = 5), non-responders (n = 6) and relapsers (n = 2). Finally, we estimated BAFF levels after complete depletion of B cells with rituximab in patients with chronic HCV with MC (n = 3). Serum levels of BAFF were increased in chronic HCV with MC, but not in chronic HBV infection, suggesting an association between BAFF and cryoglobulinaemia. Peg-I increased BAFF levels in serum and this paralleled HCV RNA very closely. Serum BAFF levels at week 12 of therapy with peg-I and R were significantly higher in responders than non-responders. Finally, B cell depletion was associated with markedly increased levels of BAFF.

Hepatitis C infection and chronic renal diseases

Hepatitis C virus (HCV) infection and chronic renal diseases can be linked in two different ways. Some forms of renal disease are precipitated by HCV infection, while patients with end-stage renal disease are at increased risk for acquiring HCV infection. Patients with chronic HCV infection and renal disease have a poor prognosis. Most studies on treatment of HCV and renal diseases have been uncontrolled trials with small number of subjects. So, there is a lack of evidence-based recommendations and guidelines on the management of this condition. In this review, we will attempt to provide the most recent insights on HCV infection both as a extrahepatic manifestations and as a complication of end-stage renal patients.

Hepatitis C virus: the role of molecular mimicry in response to interferon treatment

Chronic hepatitis C virus (HCV) infection is one of the major causes of chronic liver disease worldwide. In order for HCV to persist, the virus must escape immune recognition or inhibit the host immune response. The NS5A protein contains the interferon sensitivity-determining region (ISDR) and is able to repress dsRNA-dependent protein kinase (PKR) thus influencing the response to interferon (IFN) therapy. Patients who respond to IFN therapy have stronger antibody reactivity against the NS5A compared to IFN non-responders. Therefore, given the possible role for the ISDR in IFN resistance and differential antibody reactivity, it is possible that variation in ISDR may be involved in viral immune escape and development of persistent HCV infection employing aspects of host mimicry. In this study, pre-treatment samples obtained from HCV infected patients were used to investigate the effect of different NS5A ISDR variants on the IFN antiviral response and their involvement in immune evasion. The NS5A was identified as a homologue of the variable region of immunoglobulins (Ig). The IFN resistant genotypes had higher levels of similarity to Ig compared to IFN sensitive genotypes. Expression of NS5A-6003 (HCV genotype 1b) and NS5A-6074 (HCV genotype 2a) was able to rescue vesicular stomatitis virus (VSV) from IFN inhibition and restore luciferase activity. A correlation between Ig-like NS5A structure and also antibody response with the outcome of IFN treatment was observed.

B cells in chronically hepatitis C virus-infected individuals lack a virus-induced mutation signature in the TP53, CTNNB1, and BCL6 genes

Hepatitis C virus (HCV) is considered to have a causative role in B-cell lymphoproliferative diseases, including B-cell lymphomas, in chronic virus carriers. Previous data from in vitro HCV-infected B-cell lines and peripheral blood mononuclear cells from HCV-positive individuals suggested that HCV might have a direct mutagenic effect on B cells, inducing mutations in the tumor suppressor gene TP53 and the proto-oncogenes BCL6 and CTNNB1 (β-catenin). To clarify whether HCV indeed has a mutagenic effect on B cells in vivo, we analyzed naive and memory B cells from the peripheral blood of four chronic HCV carriers and intrahepatic B cells from the livers of two HCV-positive patients for mutations in the three reported target genes. However, no mutations were found in the TP53 and CTNNB1 genes. For BCL6, which is a physiological target of the somatic hypermutation process in germinal-center B cells, the mutation levels identified were not higher than those reported in the respective B-cell subsets in healthy individuals. Hence, we conclude that in chronic HCV carriers, the virus does not generally induce mutations in the cancer-related genes TP53, CTNNB1, and BCL6 in B cells. Based on these findings, new targets have to be investigated as potential mediators of HCV-associated B-cell lymphomagenesis.

HCV-related nervous system disorders

Chronic infection with hepatitis C virus (HCV) is associated with a wide spectrum of extrahepatic manifestations, affecting different organ systems. Neurological complications occur in a large number of patients and range from peripheral neuropathy to cognitive impairment. Pathogenetic mechanisms responsible for nervous system dysfunction are mainly related to the upregulation of the host immune response with production of autoantibodies, immune complexes, and cryoglobulins. Alternative mechanisms include possible extrahepatic replication of HCV in neural tissues and the effects of circulating inflammatory cytokines and chemokines.

Hepatitis C virus infection and mixed cryoglobulinemia

Hepatitis C virus (HCV) chronic infection is recognized as the major cause of mixed cryoglobulinemia (MC). Its persistence represents a continuous stimulus for host immune system with production of circulating immune complexes (ICs), one-third of them with cryoprecipitate property. Several factors contribute to the biological activities of ICs, many of which are not completely known. Among them, complement factors play a crucial role in the cold-insoluble ICs-mediated vasculitis, involving primarily small blood vessels in different tissues including skin, kidney, peripheral, and central nervous system. Liver represents the major target of HCV infection with inflammatory infiltrates, resembling secondary lymphoid follicles. Cytokine like CXCL13 contribute to B-cell homing in intraportal lymphoid aggregates, in which B-cell clonal selection may arise. B-cell clonal expansion starts as an antigen-driven event and expands towards indolent and malignant B-cell proliferation. Occurrence of intrahepatic B-cell clonalities correlates with extrahepatic clinical manifestations of HCV infection. In this context, cryoglobulinemic patients should be considered a peculiar HCV-infected population that needs a clinical multidisciplinary approach and more articulated therapeutic measures.

Current treatment of hepatitis C-associated rheumatic diseases

The hepatitis C virus (HCV) is both hepatotropic and lymphotropic, responsible for a great number of hepatic and extrahepatic immune-system disorders that comprise the so-called HCV syndrome. HCV-associated rheumatic diseases are characterized by frequent clinico-serological overlap; therefore, correct classification of individual patients is necessary before therapeutic decisions are made. This is particularly difficult to do, however, because of the coexistence of viral infection and complex autoimmune alterations. In this context, mixed cryoglobulinemia syndrome (MCs) represents the prototype of virus-related autoimmune-lymphoproliferative diseases. MCs can be treated at different levels by means of etiological treatment with antivirals (peg-interferon-alpha plus ribavirin) aimed at HCV eradication and/or pathogenetic/symptomatic treatments directed to both immune-system alterations and the vasculitic process (rituximab, cyclophosphamide, steroids, plasmapheresis, and so on). In clinical practice, the therapeutic strategy should be modulated according to severity/activity of the MCs and possibly tailored to each individual patient's conditions. Cryoglobulinemic skin ulcers may represent a therapeutic challenge, which should be managed by means of both local and systemic treatments. HCV-associated arthritis should be differentiated from the simple comorbidity of HCV infection and classical rheumatoid arthritis. It may be treated with low doses of steroids and/or hydroxychloroquine; the use of biologics (rituximab) may be considered in more severe cases. Primary Sjögren's syndrome is rarely associated with HCV infection, while sicca syndrome and myalgia are frequently detectable in hepatitis C patients, with or without cryoglobulinemic vasculitis. Other autoimmune rheumatic disorders (poly/dermatomyositis, polyarteritis nodosa, osteosclerosis, fibromyalgia, and so on) have been reported as potentially associated with HCV infection in patient populations from different countries, suggesting the role of genetic and/or environmental co-factors. The therapeutic approach to these disorders should be decided according to each individual patient's evaluation, including hepatic, virological, and immunological findings.

Hepatitis C virus-related lymphomagenesis in a mouse model

B cell non-Hodgkin lymphoma is a typical extrahepatic manifestation frequently associated with hepatitis C virus (HCV) infection. The mechanism by which HCV infection leads to lymphoproliferative disorder remains unclear. Our group established HCV transgenic mice that expressed the full HCV genome in B cells (RzCD19Cre mice). We observed a 25.0% incidence of diffuse large B cell non-Hodgkin lymphomas (22.2% in male and 29.6% in female mice) within 600 days of birth. Interestingly, RzCD19Cre mice with substantially elevated serum-soluble interleukin-2 receptor α-subunit (sIL-2Rα) levels (>1000 pg/mL) developed B cell lymphomas. Another mouse model of lymphoproliferative disorder was established by persistent expression of HCV structural proteins through disruption of interferon regulatory factor-1 (irf-1^_/_/CN2 mice). Irf-1^_/_/CN2 mice showed extremely high incidences of lymphomas and lymphoproliferative disorders. Moreover, these mice showed increased levels of interleukin (IL)-2, IL-10, and Bcl-2 as well as increased Bcl-2 expression, which promoted oncogenic transformation of lymphocytes.

The association of cryoglobulinaemia with sustained virological response in patients with chronic hepatitis C

Previous reports suggest cryoglobulinemia might influence the hepatitis C virus (HCV) infection clinical course and treatment response but this association has not been thoroughly evaluated. We aimed to assess the relationship between cryoglobulinemia and sustained viral response (SVR) in patients treated for HCV infection. We included patients with HCV infection treated from January 2003 through December 2006. Biochemical analyses, detection cryoglobulinemia, and liver biopsies were performed prior to treatment. Genotype 1 or 4 infections received Peg-interferon (IFN) alpha-2a or -2b for 48 weeks; genotypes 2 or 3 received IFN alpha for 24 weeks. All patients also received ribavirin. Of 329 enrolled patients, 242 (73%) were male and the median age was 43 years. Cryoglobulinemia was detected in 196 (59.6%) patients; liver biopsy was performed in 301. Multivariate analysis showed an association of cryoglobulinemia with severe active necroinflammation (A3) (adjusted odds ratio [AOR] = 9.48; 95% confidence interval [CI]: 1.50-59.92) and rheumatoid factor (RF) level (AOR = 1.01; 95% CI: 1.00-1.02). Variables associated with advanced fibrosis were age, aspartate aminotransferase and alkaline phosphatase levels, alcohol use, and presence of diabetes. Variables independently associated with SVR were cryoglobulinemia (AOR = 2.33, 95% CI: 1.26-4.32), absence of cirrhosis (AOR = 4.5, 95% CI: 1.4-14.80), and RF level (AOR = 1.008, 95% CI: 1.001-1.014). Our findings suggest cryoglobulinemia is associated with severe necroinflammatory activity in HCV-infected patients. We also provide the first evidence for an association between cryoglobulinemia and higher SVR rates, highlighting its potential role as a prognostic factor for treatment response.

Possible recruitment of peripheral blood CXCR3+ CD27+ CD19+ B cells to the liver of chronic hepatitis C patients

It has been suggested that hepatitis C virus (HCV) infects not only hepatocytes but also immune cells, including B cells. HCV infection of B cells is the likely cause of B-cell dysregulation disorders such as mixed cryoglobulinemia, rheumatoid factor production, and B-cell lymphoproliferative disorders that may evolve into non-Hodgkin's lymphoma. To clarify the effects of chronic HCV infection on B-cell dynamics, peripheral B cells from chronic hepatitis C patients (CHC) were characterized. We found that the frequency of CD27(+) B cells, that is memory phenotype, was significantly reduced in the peripheral blood of CHC. At the same time, the amount of IFN-gamma-inducible protein-10 (IP-10), a CXCR3 ligand, was markedly elevated in the plasma of CHC. Furthermore, the CD27(+) B-cell population was found to highly express CXCR3 in CHC, thus suggesting that the CD27(+) B-cell population was recruited from peripheral blood to the inflammatory site of the liver of CHC, where IP-10 is produced. Immunohistochemical analyses of intrahepatic lymphocytes indicated that CXCR3(+) B cells were infiltrated in the liver of CHC. Our results thus offer new insight into the role of memory B cells in the HCV pathogenesis.

Persistent expression of the full genome of hepatitis C virus in B cells induces spontaneous development of B-cell lymphomas in vivo

Extrahepatic manifestations of hepatitis C virus (HCV) infection occur in 40%-70% of HCV-infected patients. B-cell non-Hodgkin lymphoma is a typical extrahepatic manifestation frequently associated with HCV infection. The mechanism by which HCV infection of B cells leads to lymphoma remains unclear. Here we established HCV transgenic mice that express the full HCV genome in B cells (RzCD19Cre mice) and observed a 25.0% incidence of diffuse large B-cell non-Hodgkin lymphomas (22.2% in males and 29.6% in females) within 600 days after birth. Expression levels of aspartate aminotransferase and alanine aminotransferase, as well as 32 different cytokines, chemokines and growth factors, were examined. The incidence of B-cell lymphoma was significantly correlated with only the level of soluble interleukin-2 receptor α subunit (sIL-2Rα) in RzCD19Cre mouse serum. All RzCD19Cre mice with substantially elevated serum sIL-2Rα levels (> 1000 pg/mL) developed B-cell lymphomas. Moreover, compared with tissues from control animals, the B-cell lymphoma tissues of RzCD19Cre mice expressed significantly higher levels of IL-2Rα. We show that the expression of HCV in B cells promotes non-Hodgkin-type diffuse B-cell lymphoma, and therefore, the RzCD19Cre mouse is a powerful model to study the mechanisms related to the development of HCV-associated B-cell lymphoma.