Interleukin-10 - 1082 GG polymorphism influences the occurrence and the clinical characteristics of hepatitis C virus infection

Hepatitis Virus-associated Non-hodgkin Lymphoma: Pathogenesis and Treatment Strategies

Over the last decade, epidemiological studies have discovered a link between hepatitis C virus (HCV) and hepatitis B virus (HBV) infection and non-Hodgkin lymphoma (NHL). The regression of HCV-associated NHL after HCV eradication is the most compelling proof supporting HCV infection's role in lymphoproliferative diseases. HBV infection was found to significantly enhance the incidence of NHL, according to the epidemiological data. The exact mechanism of HCV leading to NHL has not been fully clarified, and there are mainly the following possible mechanisms: (1) Indirect mechanisms: stimulation of B lymphocytes by extracellular HCV and cytokines; (2) Direct mechanisms: oncogenic effects mediated by intracellular HCV proteins; (3) hit-and-run mechanism: permanent genetic B lymphocytes damage by the transitional entry of HCV. The specific role of HBV in the occurrence of NHL is still unclear, and the research on its mechanism is less extensively explored than HCV, and there are mainly the following possible mechanisms: (1) Indirect mechanisms: stimulation of B lymphocytes by extracellular HBV; (2) Direct mechanisms: oncogenic effects mediated by intracellular HBV DNA. In fact, it is reasonable to consider direct-acting antivirals (DAAs) as first-line therapy for indolent HCV-associated B-NHL patients who do not require immediate chemotherapy. Chemotherapy for NHL is affected by HBV infection and replication. At the same time, chemotherapy can also activate HBV replication. Following recent guidelines, all patients with HBsAg positive/HBV DNA≥2,000 IU/mL should be treated for HBV. The data on epidemiology, interventional studies, and molecular mechanisms of HCV and HBV-associated B-NHL are systematically summarized in this review.

Role of Inflammatory/Immune Response and Cytokine Polymorphisms in the Severity of Chronic Hepatitis C (CHC) before and after Direct Acting Antiviral (DAAs) Treatment

Host regulatory immune response is involved in the hepatic inflammatory process caused by the hepatitis C virus (HCV). We aimed to determine if HCV clearance with direct-acting antivirals (DAAs) changes the hepatic fibrosis stage, biochemical parameters of liver injury, and inflammatory/immune responses. Sample: 329 chronic hepatitis C (CHC) patients, 134 of them treated with DAAs. Liver fibrosis was evaluated by transient elastography (FibroScan), biochemical and cellular parameters were determined by standard methods, cytokine concentration by enzyme-linked immunoabsorbent assay (ELISA), and genetic polymorphisms by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) or endpoint genotyping. Before DAA treatment, severe fibrosis or cirrhosis (F3/4) was associated with higher values of tumor necrosis factor-alpha (TNF-α) and genotypes transforming growth factor-beta-509 C/T_CC (TGF-β-509 C/T_CC), interleukine-10-1082 T/C_CC (IL-10-1082 T/C_CC), and IL-10-592 G/T_GT. After DAA treatment, fewer F3/4 patients and lower values of TNF-α were found. Patients with TNF-α-308 G/A_GG and IL-10-592 G/T_GT were at risk for F3/4. Lack of improvement of liver fibrosis was associated with lower baseline values of platelet count for genotypes TNF-α-308 G/A_GG and haplotype TT/GG of IL-10-1082 T/C and IL-10-592 G/T. Our study showed decreased liver fibrosis/inflammation and normalization of liver injury biomarkers after DAA treatment. It also points to the importance of suppressing the pro-inflammatory response by DAAs in the resolution of hepatitis C, contributing to the improvement of liver damage evaluated by transient elastography.

Environmental risk factors for non-Hodgkin's lymphoma: umbrella review and comparison of meta-analyses of summary and individual participant data

Objectives

To summarise the range, strength, and validity of reported associations between environmental risk factors and non-Hodgkin's lymphoma, and to evaluate the concordance between associations reported in meta-analyses of summary level data and meta-analyses of individual participant data.

Design

Umbrella review and comparison of meta-analyses of summary and individual participant level data.

Data sources

Medline, Embase, Scopus, Web of Science Core Collection, Cochrane Library, and Epistemonikos, from inception to 23 July 2021.

Eligibility criteria for selecting studies

English language meta-analyses of summary level data and of individual participant data evaluating associations between environmental risk factors and incident non-Hodgkin's lymphoma (overall and subtypes).

Data extraction and synthesis

Summary effect estimates from meta-analyses of summary level data comparing ever versus never exposure that were adjusted for the largest number of potential confounders were re-estimated using a random effects model and classified as presenting evidence that was non-significant, weak (P<0.05), suggestive (P<0.001 and >1000 cases), highly suggestive (P<0.000001, >1000 cases, largest study reporting a significant association), or convincing (P<0.000001, >1000 cases, largest study reporting a significant association, I2 <50%, 95% prediction interval excluding the null value, and no evidence of small study effects and excess significance bias) evidence. When the same exposures, exposure contrast levels, and outcomes were evaluated in meta-analyses of summary level data and meta-analyses of individual participant data from the International Lymphoma Epidemiology (InterLymph) Consortium, concordance in terms of direction, level of significance, and overlap of 95% confidence intervals was examined. Methodological quality of the meta-analyses of summary level data was assessed by the AMSTAR 2 tool.

Results

We identified 85 meta-analyses of summary level data reporting 257 associations for 134 unique environmental risk factors and 10 subtypes of non-Hodgkin's lymphoma nearly all (79, 93%) were classified as having critically low quality. Most associations (225, 88%) presented either non-significant or weak evidence. The 11 (4%) associations presenting highly suggestive evidence were primarily for autoimmune or infectious disease related risk factors. Only one association, between history of coeliac disease and risk of non-Hodgkin's lymphoma, presented convincing evidence. Of 40 associations reported in meta-analyses of summary level data that were also evaluated in InterLymph meta-analyses of individual participant data, 22 (55%) pairs were in the same direction, had the same level of statistical significance, and had overlapping 95% confidence intervals; 28 (70%) pairs had summary effect sizes from the meta-analyses of individual participant data that were more conservative.

Conclusion

This umbrella review suggests evidence of many meta-analyses of summary level data reporting weak associations between environmental risk factors and non-Hodgkin's lymphoma. Improvements to primary studies as well as evidence synthesis in evaluations of evironmental risk factors and non-Hodgkin's lymphoma are needed.

Review registration number

PROSPERO CRD42020178010.

Intrahepatic interleukin 10 expression modulates fibrinogenesis during chronic HCV infection

Introduction

Liver fibrosis is a result of continuous damage to the liver combined with accumulation of the extracellular matrix and is characteristic of most chronic liver diseases such as hepatitis C virus (HCV) infection.

Methods

This study evaluated interleukin 10 (IL10) expression in the liver and plasma of 45 HCV patients and its association with the pathogenesis and progression of liver fibrosis. The expression of transforming growth factor beta (TGFB1) was also assessed. Patients were divided into three groups according to the METAVIR classification (F0-F1, F2 and F3-F4); there was also a control group (n = 8).

Results

In the control group, high intrahepatic IL10 mRNA expression showed a positive association with F0-F1 fibrosis, no inflammation, low concentrations of liver enzymes and a high viral load; conversely, low intrahepatic IL10 mRNA expression showed a negative association with fibrosis progression. Intrahepatic TGFB1 mRNA expression was greater in the HCV group than in the control group, and regarding different disease phases, its expression increased as fibrosis evolved to more severe forms.

Conclusion

Intrahepatic IL10 mRNA expression decreases with persistent fibrosis, probably due to the production of TGF-β1, a potent antimitotic and fibrogenic cytokine. IL10 restricts and decreases the immune response and limits the fibrogenic response; however, a decrease in IL10 favors persistent inflammatory infiltrate, resulting in severe fibrosis.

TIGIT limits immune pathology during viral infections

Co-inhibitory pathways have a fundamental function in regulating T cell responses and control the balance between promoting efficient effector functions and restricting immune pathology. The TIGIT pathway has been implicated in promoting T cell dysfunction in chronic viral infection. Importantly, TIGIT signaling is functionally linked to IL-10 expression, which has an effect on both virus control and maintenance of tissue homeostasis. However, whether TIGIT has a function in viral persistence or limiting tissue pathology is unclear. Here we report that TIGIT modulation effectively alters the phenotype and cytokine profile of T cells during influenza and chronic LCMV infection, but does not affect virus control in vivo. Instead, TIGIT has an important effect in limiting immune pathology in peripheral organs by inducing IL-10. Our data therefore identify a function of TIGIT in limiting immune pathology that is independent of viral clearance.

Interleukin-10 promoter gene polymorphisms are associated with the first major depressive episode in chronic hepatitis C patients

AIMS

To investigate the association of IL10 SNPs in chronic hepatitis C (CHC) patients with and without the first major depressive episode (MDE), as well as their association with plasma levels of target cytokines.

METHODS

A hundred and thirty two CHC patients (32 with and 100 without first MDE) and 98 controls were prospectively enrolled in this cross-sectional study. MDE was diagnosed by a psychiatrist, using the Mini International Neuropsychiatric Interview Plus 5.0. IL10 polymorphisms (-1082 G/A, -819C/T and -592C/A IL10 SNPs) were evaluated by Taqman SNP genotyping assay. Plasma concentrations of IL-2, IL-6, IL-10, IFN-γ and TNF-α were determined using the Human Th1/Th2 Cytometric Bead Array kit. The associations were investigated by logistic models.

RESULTS

The frequencies of the studied IL10 SNPs did not differ between the CHC patients and controls. The first MDE was positive and independently associated with the IL10-1082*A, IL10-819*T and IL10-592*A (ATA) low producer haplotype (OR = 1.50; 95% CI = 1.11-2.04; P = 0.009) and current alcohol misuse (OR = 4.29; 95% CI = 1.22-15.05; P = 0.02), and inversely associated with increasing age (OR = 0.94; 95% CI = 0.91-0.98; P = 0.006). In addition, plasma level of TNF-α was significantly higher in the carriers than in the non-carriers of the IL10 ATA haplotype in patients with the first MDE. The IL-10 and IL-2 plasma levels were significantly higher in the carriers than in non-carriers of the IL10 GCC high producer haplotype, demonstrating the functionality of the studied IL10 polymorphisms.

CONCLUSIONS

This is the first study to demonstrate that the IL10 low producer ATA haplotype is associated with the first MDE in patients with CHC.

Hepatitis C virus infection and non-hepatocellular malignancies in the DAA era: A systematic review and meta-analysis

BACKGROUND AND AIMS

Direct antiviral agents have greatly improved therapeutic options for chronic hepatitis C. Indeed, former "difficult-to-treat" patients can now be treated and can achieve sustained response. Hepatitis C virus (HCV) is associated with hepatocellular carcinoma and with B-cell non-Hodgkin lymphoma (B-NHL). Other malignancies have been reported to be associated with HCV infection albeit with various grades of evidence. Antineoplastic treatment is often reduced or suspended in HCV-positive cancer patients to avoid "HCV reactivation." In this setting, antiviral therapy combined with antineoplastic protocols may improve the outcome. For this reason, we conducted a systematic review and a meta-analysis to update the association between HCV infection and non-hepatocellular malignancies, and to shed light on the effects exerted by antiviral treatment on the natural history of oncological diseases.

METHODS

Relevant studies were identified by searching PUBMED, EMBASE and MEDLINE up to 1 August 2018. Pooled risk estimates were calculated with random-effects models according to PRISMA guidelines.

RESULTS

A total of 58 studies were included in the analysis: 27 studies of the association between HCV and B-NHL(OR 3.36; 95% CI 2.40-4.72;P < 0.00001);13 studies of the association between sustained virological response and progression-free survival (PFS) in B-NHL patients(OR 9.34; 95% CI 4.90-17.79; P < 0.00001); 13 studies of the association between HCV and intrahepatic-cholangio-carcinoma (OR 3.95;95% CI 2.25-6.94; P < 0.00001); and 5 studies of the association between HCV infection and pancreatic adeno-carcinoma(OR 1.60; 95% CI:1.25-2.04; P = 0.0002).

CONCLUSIONS

This study updates the strong association between B-NHL and HCV infection, confirms the association between HCV and non-hepatocellular tumours, and demonstrates a very strong association between viral eradication and a better outcome of HCV-positive B-NHL.

The combined polymorphisms of interleukin-6-174GG genotype and interleukin-10 ATA haplotype are associated with a poor quality of life in patients with chronic hepatitis C

PURPOSE

Chronic hepatitis C (CHC) is associated with a decreased health-related quality of life (HRQOL). More recent studies have pointed toward a genetic basis of patient-reported quality of life outcomes. Taking into account that the influence of single-nucleotide polymorphisms (SNPs) on the HRQOL of CHC patients has not been studied, we investigated the combined IL10-1082G/A, - 819C/T, and - 592C/A SNPs, and IL6-174G/C SNP. We also evaluated the association between demographic, clinical, psychiatric, virological, and genetic variables with domains and summaries of HRQOL in CHC patients.

METHODS

132 consecutive CHC patients and 98 controls underwent psychiatric evaluation by using the Mini International Neuropsychiatric Interview. HRQOL was assessed by a generic questionnaire, the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), and by the specific Liver Disease Quality of Life Questionnaire (LDQOL). IL6 and IL10 polymorphisms were evaluated by Taqman SNP genotyping assay. Multivariate analysis was used to evaluate the associations.

RESULTS

Major depressive disorder was associated with lower SF-36 and LDQOL scores in seven and ten domains, respectively. Diabetes and hypertension were also associated with reduced HRQOL. CHC patients carrying the combination of IL10 ATA haplotype/IL6-GG genotype had lower scores in the SF-36-physical functioning domain, and reduced scores in the LDQOL effects of liver disease on activities of daily living, quality of social interaction, and sexual function domains than the non-carriers of the combined haplotype/genotype.

CONCLUSION

This is the first study to demonstrate that combined IL6 high-producer GG genotype and IL10 low-producer ATA haplotype is associated with poorer HRQOL in CHC patients.

Efficacy and safety of new direct antiviral agents in hepatitis C virus-infected patients with diffuse large B-cell non-Hodgkin's lymphoma

The association of hepatitis C virus (HCV) with non-Hodgkin's lymphoma (NHL) has been demonstrated throughout the world. The new interferon-free direct antiviral agents (DAAs) showed high efficacy and safety, and preliminary data seem to confirm their activity on low-grade NHL. The question arises as whether or not-and how-to treat the HCV-positive patients suffering from diffuse large B-cell lymphomas (DLBCLs). The aim of this observational study was to evaluate whether DAA antiviral treatment of DLBCL/HCV-infected patients in concomitance with chemotherapy is a safe and effective option. Twenty (13 males and 7 females) HCV genotype 1b-positive subjects, undergoing chemotherapy for DLBCL, were enrolled between June 2015 and December 2015. After informed consent, all patients underwent antiviral therapy (AVT) with sofosbuvir/ledipasvir and chemotherapy (14 rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone and 6 cyclophosphamide, doxorubicin, vincristine, and prednisone) for DLBCL. Complete hematological (Revised European-American Lymphoma classification, Ann Arbor, and International Prognostic Index [IPI] scores) and hepatological (viral markers, liver stiffness, and biochemical parameters) evaluations were made. A historical retrospective cohort of 101 DLBCL/HCV-positive patients not undergoing AVT was enrolled for comparison. DAA-treated and untreated patients were similar for sex distribution, IPI score, and NHL stage, and differed for age (older in treated), chemotherapy and use of AVT. Overall survival (OS) and disease-free survival (DFS) were evaluated among a 52-week of follow-up. No statistical difference was found in OS after 52 weeks (P = 0.122), whereas a statistically significant higher DFS was achieved in treated patients (P = 0.036). At the multivariate analysis, only IPI score and AVT were independently correlated with a better DFS. No differences in adverse events were reported.

CONCLUSION

DAA treatment in concomitance with chemotherapy was shown to be safe and effective in influencing remission of aggressive lymphomas in HCV patients. (Hepatology 2018;67:48-55).

Notch4 and mhc class II polymorphisms are associated with hcv-related benign and malignant lymphoproliferative diseases

Mixed cryoglobulinemia (MC), is a HCV-related, clinically benign, lymphoproliferative disorder (LPD) that may evolve into a non Hodgkin's lymphoma (NHL). Significant associations were found between two single nucleotide polymorphisms near NOTCH4 (rs2071286) and the HLA class II (rs9461776) genes and HCV-related MC syndrome (MCS). We analyzed NOTCH4 rs2071286 and HLA-II rs9461776 in 3 HCV-related LPD groups (asymptomatic MC, MCS, NHL) with HCV infection without lymphoproliferative disorders.

We found a positive relationship between NOTCH4 rs207186 T minor allele frequency (MAF) and patients with HCV-related LPDs at risk of NHL (Chi-square test for trend = 14.84 p = 0.0001), in accordance with an over-dominant model in the NHL group (CT vs CC + TT, OR=1.88, 95% CI 1.24–2.83, p = 0.0026).

Regarding HLA II rs9461776, G MAF increased in patients with HCV-related LPDs at risk of NHL (Chi-square test for trend = 8.40 p = 0.0038), in accordance with a recessive genotypic model in the NHL group (G/G vs A/A + A/G, OR = 11.07, 95% CI 2.37–51.64, p = 0.0022).

Both NOTCH4 rs2071286 and HLA-II rs9461776 were present on chromosome 6 and showed D’ and r values of linkage disequilibrium (LD) of about 0.5 values, thereby suggesting there is no extensive LD in the HCV+ population.

This data shows that the previously demonstrated association between NOTCH4 rs2071286 and HLA-II rs9461776 polymorphisms and HCV-related MCS could be extended to overall patients with HCV-related LPDs. The significant relationship between rs2071286 and rs9461776 MAF and the increased risk for NHL, suggests their use as non-invasive markers to categorize patients at risk of lymphoma.

Tumour necrosis factor -308 and -238 promoter polymorphisms are predictors of a null virological response in the treatment of Brazilian hepatitis C patients

Certain host single nucleotide polymorphisms (SNPs) affect the likelihood of a sustained virological response (SVR) to treatment in subjects infected with hepatitis C virus (HCV). SNPs in the promoters of interleukin (IL)-10 (-1082 A/G, rs1800896), myxovirus resistance protein 1 (-123 C/A, rs17000900 and -88 G/T, rs2071430) and tumour necrosis factor (TNF) (-308 G/A, rs1800629 and -238 G/A, rs361525) genes and the outcome of PEGylated α-interferon plus ribavirin therapy were investigated. This analysis was performed in 114 Brazilian, HCV genotype 1-infected patients who had a SVR and in 85 non-responders and 64 relapsers. A significantly increased risk of having a null virological response was observed in patients carrying at least one A allele at positions -308 [odds ratios (OR) = 2.58, 95% confidence intervals (CI) = 1.44-4.63, p = 0.001] or -238 (OR = 7.33, 95% CI = 3.59-14.93, p < 0.001) in the TNF promoter. The risk of relapsing was also elevated (-308: OR = 2.87, 95% CI = 1.51-5.44, p = 0.001; -238: OR = 4.20, 95% CI = 1.93-9.10, p < 0.001). Multiple logistic regression of TNF diplotypes showed that patients with at least two copies of the A allele had an even higher risk of having a null virological response (OR = 16.43, 95% CI = 5.70-47.34, p < 0.001) or relapsing (OR = 6.71, 95% CI = 2.18-20.66, p = 0.001). No statistically significant association was found between the other SNPs under study and anti-HCV therapy response.

Association of Interleukin-10 -3575T>A and -1082A>G polymorphisms with non-Hodgkin lymphoma susceptibility: a comprehensive review and meta-analysis

A number of studies have investigated the associations between IL-10 polymorphisms and non-Hodgkin lymphoma (NHL) susceptibility; however, the conclusions were still contradictory. To acquire a more precise estimation of the association, we performed the current meta-analysis. We systematically searched publications from EMBASE and MEDLINE, and calculated pooled odds ratios (ORs) and 95 % confidence intervals (CIs) using either fixed-effects or random-effects model. Genotype-based IL-10 mRNA expression analysis was performed using online public database of 270 individuals with three different ethnicities. A total of 10,703 cases and 11,823 controls from 10 studies were included for the -3575T>A polymorphism, 10,226 cases and 12,215 controls from 17 studies for the -1082A>G polymorphism. Pooled results indicated that IL-10 -3575T>A was associated with increased risk of diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL), especially for Caucasians and hospital-based population. There was no association between IL-10 -1082A>G and NHL risk. However, subgroup analysis showed that IL-10 -1082GG might confer increased susceptibility to FL. In summary, this meta-analysis indicated that -3575T>A polymorphism was associated with altered NHL susceptibility for Caucasians and hospital-based population, especially for DLBCL and FL subtypes. The -1082A>G polymorphism may contribute to increased FL risk. Further large-scale population studies among different ethnicities are needed to validate these results.

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.

Impact of the IL-10 Promoter Gene Polymorphisms in the Severity of Chronic Hepatitis B Infection

BACKGROUND

Interleukin-10 (IL-10) is an important anti-inflammatory cytokine. The polymorphisms of its promoter gene have been considered to be related with the chronicity of hepatitis B infection.

OBJECTIVES

The aim of this study was to evaluate the polymorphisms at different positions in the IL-10 promoter gene in patients with chronic hepatitis B.

PATIENTS AND METHODS

Totally, 166 patients with chronic hepatitis B infection were enrolled. Genotypes at different positions (i.e. -819, - 592, and - 1082) in the IL-10 gene promoter were determined.

RESULTS

The C/A genotype at position -592, C/T genotype at position -819, and GCC/ATA haplotype of the IL-10 gene promoter were significantly more common in the patients with cirrhosis. The genotypes were significantly different between the hepatitis B e antigen (HBeAg)-negative and HBeAg-positive patients at position -592 (C/A and C/C), position -819 (C/C and C/T), and position -1082 (A/A and G/A).

CONCLUSIONS

Some IL-10 promoter gene polymorphisms predisposed the infected hepatitis B virus cases to cirrhosis in our study population.

Association of IL10 -819C>T and -592C>A Polymorphisms with Non-Hodgkin Lymphoma Susceptibility: Evidence from Published Studies

Numerous studies have investigated the association of IL10 -819C>T and -592C>A polymorphisms with non-Hodgkin lymphoma (NHL) susceptibility, and yet reported conflicting results. With this in mind, we performed the current meta-analysis with an aim to verify actual causative variants underlying lymphomagenesis. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the strength of the associations. Moreover, to explore the biological function of these polymorphisms, we also performed genotype-based mRNA expression analysis using online database derived from 270 subjects within three ethnicities. The final analysis included 11 studies with a total of 5859 NHL cases and 6893 controls for the IL10 -819C>T polymorphism, and 11 studies with 6277 cases and 7350 controls for the IL10 -592C>A polymorphism. No significant association was observed for these two polymorphisms in either the overall analysis or the stratification analyses by ethnicity and source of controls. Nevertheless, stratification analyses demonstrated a significant decreased risk associated with the IL10 -819C>T polymorphism (homozygous: OR=0.81, 95% CI=0.66-0.99, and recessive model: OR=0.80, 95%CI=0.65-0.98) and IL10 -592C>A polymorphism (homozygous: OR=0.80, 95% CI=0.66-0.99, and recessive model: OR=0.80, 95%CI=0.66-0.97) among patients with diffuse large B-cell lymphoma (DLBCL). Despite some limitations, this meta-analysis indicates that polymorphisms in IL10 gene may contribute to DLBCL susceptibility.

Polymorphisms of IL-10 gene in patients infected with HCV under antiviral treatment in southern Brazil

Interleukin-10 (IL-10) is a cytokine that plays an important role in the regulation of the immune system. Gene polymorphisms of IL-10 have been associated with the different expression levels of this cytokine. In hepatitis C virus infection, IL-10 appears to interfere with the progression of disease, viral persistence and the response to therapy. This study investigated genetic variability in the IL-10 gene promoter between patients infected with hepatitis C virus (HCV) and healthy individuals, associating the frequency of polymorphisms with different aspects of viral infection. This is a case-control study with 260 patients who were infected with HCV and 260 healthy individuals. Genotyping of the polymorphisms was performed using the technique of amplification refractory mutation system PCR (ARMS-PCR) for regions of the IL-10 gene promoter (-1082 G/A, -819 C/T, -592 C/A). The frequencies of alleles and genotypes related to polymorphisms in the IL-10 gene promoter showed a higher frequency of the G allele and genotype GG in the -1082 region between the infected group and the control group (p=0.005 and p=0.001, respectively), whereas the AA genotype was significantly more frequent in the control group. The frequencies of the haplotypes GTA and GCC were higher in the group of infected individuals, whereas the haplotype ATA was more frequent in the healthy group (p<0.006). It was also observed that the genotypes GG and AG in the region -1082 were significantly more frequent among patients infected with HCV who were in advanced stages of fibrosis and cirrhosis (p=0.042). No association was observed between polymorphisms of IL-10 and sustained virologic response (SVR).

Combined impact of hepatitis C virus genotype 1 and interleukin-6 and tumor necrosis factor-α polymorphisms on serum levels of pro-inflammatory cytokines in Brazilian HCV-infected patients

We investigated the association between hepatitis C virus (HCV) genotypes and host cytokine gene polymorphisms and serum cytokine levels in patients with chronic hepatitis C. Serum IL-6, TNF-α, IL-2, IFN-γ, IL-4, IL-10, and IL-17A levels were measured in 67 HCV patients (68.2% genotype 1 [G1]) and 47 healthy controls. The HCV patients had higher IL-6, IL-2, IFN-γ, IL-10, and IL-17A levels than the controls. HCV G1 patients had higher IL-2 and IFN-γ levels than G2 patients. The -174IL6G>C, -308TNFαG>A, and -1082IL10A>G variants were similarly distributed in both groups. However, HCV patients with the -174IL6GC variant had higher IL-2 and IFN-γ levels than patients with the GG and CC variants. Additionally, HCV patients with the -308TNFαGG genotype had higher IL-17A levels than patients with the AG genotype, whereas patients with the -1082IL10GG variant had higher IL-6 levels than patients with the AA and AG variants. A significant proportion of HCV patients had high levels of both IL-2 and IFN-γ. The subgroup of HCV patients with the G1/IL6CG/TNFαGG association displayed the highest proportions of high producers of IL-2 and IFN-γ whereas the subgroup with the G1/TNFαGG profile showed high proportions of high producers of IL-6 and IL-17A. HCV patients with other HCV/cytokine genotype associations showed no particular cytokine profile. Our results suggest that HCV genotype G1 and IL-6 and TNF-α polymorphisms have a clinically relevant influence on serum pro-inflammatory cytokine profile (IL-2 and IFN-γ) in HCV patients.

Haplotype analysis of interleukin-10 gene promoter polymorphisms in chronic hepatitis C infection: a case control study

High prevalence of hepatitis c virus (HCV) infection in some areas necessitates more investigations of the causative factors. Genetic factors that cause disruption in operation or secretion of interleukin 10 (IL-10), an anti-inflammatory cytokine, may play a role in the intensity of the disease. The aim of this study was to evaluate genetic variants of IL-10 gene polymorphisms in HCV patients and their relationship with HCV disease. Fifty HCV patients and the same number of healthy individuals who were referred to hepatitis clinic in Mashhad, northeast of Iran, were recruited. Genomic DNA was extracted from whole blood. Genotyping for IL-10 gene promoter polymorphisms in three positions (-1082 G>A, -819 C>T and -592 C>A) was conducted by amplification refractory mutation system-polymerase chain reaction. Haplotype analysis was performed using PHASE software. In a recessive analysis model of the -1082 position (GG vs. AA+AG), GG genotype was more common in patients (adjusted p = 0.02; OR = 4.66 [95% CI 1.31-16.35]). Also, ATA haplotype was more prevalent in HCV patients (adjusted p = 0.061; OR = 1.87 [95% CI 0.97-3.61]). Also, ATC/GCA diplotypes were more common in controls (adjusted p=0.002; adjusted OR = 0.27 [95% CI 0.11-0.63]). Although we found a possible association between IL-10 promoter polymorphisms and HCV infection, certain genotypes or diplotypes may confer a higher risk or susceptibility for developing HCV infection.

Polymorphisms in the TNF-α and IL-10 gene promoters and risk of psoriasis and correlation with disease severity

Several cytokines were assumed to play an essential role in the induction and the pathogenesis of psoriasis. The aim of this work was to investigate the role of TNF-α-308 and IL-10-1082 polymorphisms and their serum levels in the pathogenesis of psoriasis and determine their relation to disease severity. 110 Psoriasis patients and 120 healthy volunteers were genotyped for TNF-α-308 and IL-10-1082 polymorphism by polymerase chain reaction. Serum level of TNF-α and IL-10 were measured by ELISA. Our study demonstrated an association of IL-10-1082 polymorphism and psoriasis and between TNF α-308 polymorphism and psoriasis disease and severity. Serum TNF α increased in patients, while serum IL-10 decreased in patients with significant correlation between serum TNF-α and psoriasis severity. These results indicated that TNF-α-308 and IL-10-1082 polymorphisms imparted significant risk towards the development of psoriasis.

Transforming growth factor-β and toll-like receptor-4 polymorphisms are not associated with fibrosis in haemochromatosis

AIM: To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis.

METHODS: A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was studied, with all subjects having liver biopsy data and DNA available for testing. This study assessed the association of eight single nucleotide polymorphisms (SNPs) in a total of six genes including toll-like receptor 4 (TLR4), transforming growth factor-beta (TGF-β), oxoguanine DNA glycosylase, monocyte chemoattractant protein 1, chemokine C-C motif receptor 2 and interleukin-10 with liver disease severity. Genotyping was performed using high resolution melt analysis and sequencing. The results were analysed in relation to the stage of hepatic fibrosis in multivariate analysis incorporating other cofactors including alcohol consumption and hepatic iron concentration.

RESULTS: There were significant associations between the cofactors of male gender (P = 0.0001), increasing age (P = 0.006), alcohol consumption (P = 0.0001), steatosis (P = 0.03), hepatic iron concentration (P < 0.0001) and the presence of hepatic fibrosis. Of the candidate gene polymorphisms studied, none showed a significant association with hepatic fibrosis in univariate or multivariate analysis incorporating cofactors. We also specifically studied patients with hepatic iron loading above threshold levels for cirrhosis and compared the genetic polymorphisms between those with no fibrosis vs cirrhosis however there was no significant effect from any of the candidate genes studied. Importantly, in this large, well characterised cohort of patients there was no association between SNPs for TGF-β or TLR4 and the presence of fibrosis, cirrhosis or increasing fibrosis stage in multivariate analysis.

CONCLUSION: In our large, well characterised group of haemochromatosis subjects we did not demonstrate any relationship between candidate gene polymorphisms and hepatic fibrosis or cirrhosis.

Relationship between IL-10 gene -1082A/G and -592C/A polymorphisms and the risk of hepatitis C infection: a meta-analysis

Increasing evidence suggests that interleukin-10 (IL-10) gene promoter polymorphisms may be associated with chronic hepatitis C virus (HCV) infection and HCV clearance. To more precisely estimate the association between these variants and the risk of HCV infection, we performed a meta-analysis of 26 studies describing the IL-10-1082A/G, -819C/T, -592C/A genotypes, including 4039 chronic HCV infection cases and 2902 controls. When compared with a healthy population, the -1082GG allele had a 43% increased risk of chronic HCV infection in combined populations (GG vs GA + AA: odds ratio (OR) = 1.433, 95% confidence interval (CI) = 1.052-1.952, P = 0.023). In subgroup analysis by ethnicity, a significant increased risk was associated with the -1082GG genotype in the Caucasian population (GG vs AA: OR = 1.390, 95% CI: 1.108-1.744, P = 0.004; GG vs GA + AA: OR = 1.621, 95% CI: 1.267-2.075, P = 0.000). However, no significant association was found in Asian, African or Chinese populations. Moreover, a higher distribution of -592A was found in the spontaneously recovered population (AA vs CC: OR = 0.585, 95% CI = 0.387-0.884, P = 0.011; AA + AC vs CC: OR = 0.738, 95% CI = 0.551-0.988, P = 0.041; AA vs AC + CC: OR = 0.788, 95% CI = 0.664-0.935, P = 0.006) than that in the chronic HCV infection population. In conclusion, the IL-10-1082GG allele may increase the risk of chronic HCV infection in Caucasian population, and people carrying the IL-10-592A allele are more likely to clear HCV spontaneously.

T-cell responses in hepatitis B and C virus infection: similarities and differences

Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are global health problems affecting 600 million people worldwide. Indeed, HBV and HCV are hepatotropic viruses that can cause acute and chronic liver disease progressing to liver cirrhosis and even hepatocellular carcinoma. Furthermore, co-infections of HBV and HCV with HIV are emerging worldwide. These co-infections are even more likely to develop persistent infection and are difficult to treat. There is growing evidence that virus-specific CD4⁺ and CD8⁺ T-cell responses play a central role in the outcome and pathogenesis of HBV and HCV infection. While virus-specific T-cell responses are able to successfully clear the virus in a subpopulation of patients, failure of these T-cell responses is associated with the development of viral persistence. In this review article, we will discuss similarities and differences in HBV- and HCV-specific T-cell responses that are central in determining viral clearance, persistence and liver disease.

Three polymorphisms in the IL-10 gene and the risk of HCV infection: a meta-analysis plus a Chinese Association Study involving 1140 subjects

The influence of an immunosuppressive cytokine, interleukin-10 (IL-10), on the outcome of hepatitis C virus (HCV) infection has been increasingly reported recently. A number of polymorphisms appear to control the level of IL-10 production. Among them, −592C/A, −819C/T and −1082G/A in the IL-10 gene are three most studied single nucleotide polymorphisms. To provide a more definitive conclusion about their association with the risk of HCV infection, a meta-analysis was performed by combining and summarizing a total of 17 studies. A biological justification for the choice of genetic model was provided. The results indicated no significant association between these IL-10 polymorphisms and the susceptibility to HCV infection [–592C/A: odds ratio (OR) 0·99, 95% confidence interval (CI) 0·78–1·25; –819C/T: OR 0·90, 95% CI 0·69–1·18; –1082G/A: OR 1·34, 95% CI 0·90–2·00]. However, this analysis did not account for the possible risk modifications by other factors, such as ethnicity and virus persistence. Therefore, the effects of ethnicity and virus persistence were investigated using Bayesian meta-regression and subgroup analysis. Finally, an extended case-control association study was conducted in a Chinese population involving 1140 subjects. Both serum level and genotype data of IL-10 −1082G/A were determined. As a result, a low prevalence of G allele was observed. Significantly higher IL-10 production was observed in HCV patients, especially patients with the GG genotype.

Hepatitis C virus-mediated modulation of cellular immunity

The hepatitis C virus (HCV) is a major cause of chronic liver disease globally. A chronic infection can result in liver fibrosis, liver cirrhosis, hepatocellular carcinoma and liver failure in a significant ratio of the patients. About 170 million people are currently infected with HCV. Since 80 % of the infected patients develop a chronic infection, HCV has evolved sophisticated escape strategies to evade both the innate and the adaptive immune system. Thus, chronic hepatitis C is characterized by perturbations in the number, subset composition and/or functionality of natural killer cells, natural killer T cells, dendritic cells, macrophages and T cells. The balance between HCV-induced immune evasion and the antiviral immune response results in chronic liver inflammation and consequent immune-mediated liver injury. This review summarizes our current understanding of the HCV-mediated interference with cellular immunity and of the factors resulting in HCV persistence. A profound knowledge about the intrinsic properties of HCV and its effects on intrahepatic immunity is essential to be able to design effective immunotherapies against HCV such as therapeutic HCV vaccines.

The relationship between tumor necrosis factor-α polymorphisms and hepatitis C virus infection: a systematic review and meta-analysis

BACKGROUND AND AIMS

Hepatitis C virus (HCV) is now recognized as one of the major causes of chronic liver disease. It is also one of the most common complications in maintenance hemodialysis (HD) patients. Tumor necrosis factor (TNF)-α promoter polymorphisms are observed to modulate TNF-α levels and thought to have an effect on susceptibility to HCV infection and the virus clearance, but the results are inconsistent. In this study, a systematic review and meta-analysis of the published data was performed to evaluate the relationship between the TNF-α-238, -308 polymorphisms and HCV infection.

METHODS

A total of 15 studies published were analyzed, which were indexed from PubMed, Embase, and CNKI databases (up to December 2010). All the data were analyzed using RevMan 4.2 software. Odds ratios (OR) and confidence intervals (95% CI) were calculated by fixed or random-effects models. Heterogeneity and publication bias across the studies were also explored.

RESULTS

The data showed no significant association between TNF-α-308, -238 gene polymorphisms and the susceptibility to HCV infection in the global group (p = 0.28, p = 0.38, respectively) and the sub-groups (European, American, African, and Asian). Besides, the distributions of TNF-α-308, -238 A/G alleles were also not significantly different between the persistent infection group and the spontaneous clearance group (p = 0.64, p = 0.75, respectively).

CONCLUSION

TNF-α-238, -308 gene polymorphisms might have no effect on susceptibility to HCV infection and the virus clearance. The findings of this meta-analysis have implications in the optimal prevention of HCV in HD patients and in the guidance of future research.

Suppressive CD8+ T cells arise in the absence of CD4 help and compromise control of persistent virus

There is an urgent need to develop novel therapies for controlling chronic virus infections in immunocompromised patients. Disease associated with persistent γ-herpesvirus infection (EBV, human herpesvirus 8) is a significant problem in AIDS patients and transplant recipients, and clinical management of these conditions is difficult. Immune surveillance failure followed by γ-herpesvirus recrudescence can be modeled using murine γ-herpesvirus (MHV)-68 in mice lacking CD4(+) T cells. In contrast with other chronic infections, no obvious defect in the functional capacity of the viral-specific CD8(+) T cell response was detected. We show in this article that adoptive transfer of MHV-68-specific CD8(+) T cells was ineffective at reducing the viral burden. Together, these indicate the potential presence of T cell extrinsic suppressive factors. Indeed, CD4-depleted mice infected with MHV-68 express increased levels of IL-10, a cytokine capable of suppressing the function of both APCs and T cells. CD4-depleted mice developed a population of CD8(+) T cells capable of producing IL-10 that suppressed viral control. Although exhibiting cell surface markers indicative of activation, the IL-10-producing cells expressed increased levels of programmed death-1 but were not enriched in the MHV-68-specific compartment, nor were they uniformly CD44(hi). Therapeutic administration of an IL-10R blocking Ab enhanced control of the recrudescent virus. These data implicate IL-10 as a promising target for the restoration of immune surveillance against chronic γ-herpesvirus infection in immunosuppressed individuals.

Combined effect of pro- and anti-inflammatory cytokine gene polymorphisms on susceptibility to liver cirrhosis in Tunisian HCV-infected patients

PURPOSE

Chronic hepatitis C progression is commonly attributed to the continuous activation of the immune response with an increased production of pro-inflammatory cytokines, leading to fibrosis and ultimately to cirrhosis. On the contrary, anti-inflammatory cytokines, mainly interleukin (IL)-10 have a modulatory effect on hepatic fibrogenesis. The association between individual polymorphisms within cytokine genes and hepatitis C outcome is often weak and non-informative. Interestingly, it has been demonstrated that a combination of specific genotypes may be a more significant and powerful approach for predicting disease risk.

AIM

This study is aimed at investigating the combined effect of single nucleotide polymorphism (SNP) in IL-18 (-607C/A, -137G/C), interferon (IFN)-γ (+874T/A) and IL-10 (-1082G/A) genes on cirrhosis risk in HCV-infected patients.

METHODS

Seventy-seven chronic hepatitis C Tunisian subjects were included in this study. The patients were divided into two groups: the first included 31 non-cirrhotic patients, and the second included 46 liver cirrhosis patients. IL-18 genotyping was performed using the PCR amplification and the restriction fragment length polymorphism analysis (RFLP). IFN-γ and IL-10 polymorphisms were analyzed using the allele-specific PCR (AS-PCR).

RESULTS

The combined high-risk genotype (IL-18 -607C/*, IL-18 -137G/*, IFN-γ +874T/*, IL-10 -1082A/A) frequency was compared between patients with and those without cirrhosis. Individuals were classified according the number of high-risk genotypes as follows: (0-2), patients with at most two high-risk genotypes; (3-4), patients with at least three of the high-risk genotypes. The logistic regression analysis showed that patients harboring 3-4 putative high-risk genotypes have a fivefold higher risk for developing cirrhosis in comparison to those harboring at most two high-risk genotypes (OR = 5.19; 95% CI = 1.49-18.05; p = 0.009).

CONCLUSION

Our study showed that the co-inheritance of IL-18, IFN-γ and IL-10 specific high-risk genotypes is associated with a greater risk for liver cirrhosis.

Interleukin-10 gene polymorphisms in association with susceptibility to chronic hepatitis C virus infection: a meta-analysis study

A relationship between chronic hepatitis C virus (HCV) infection and interleukin-10 (IL-10) gene polymorphisms has been reported with controversial results in different studies. In an effort to solve this controversy, we quantitatively summarized ten studies on this relationship by means of meta-analysis. Our analysis included ten case-control studies with 992 cases of chronic HCV infection and 1,123 controls. Analyses were performed with STATA version 9.0. The results showed that the IL-10 -1082GG genotype significantly increased the risk for persistent HCV infection (AA vs. GG: OR = 0.680, 95% CI = 0.489-0.947, P = 0.022; AG vs. GG: OR = 0.608, 95% CI = 0.439-0.840, P = 0.003; GG vs. AG + AA: OR = 1.570, 95% CI = 1.160-2.123, P = 0.003), but no statistically significant differences were observed between cases and controls for IL-10 -819C/T and IL-10 -592C/A polymorphisms (P > 0.05). In conclusion, this meta-analysis suggested that the IL-10 -1082GG genotype was associated with increased susceptibility for chronic HCV infection.

Role of host genetic factors in the outcome of hepatitis C virus infection

The natural history of hepatitis C virus (HCV) infection is determined by a complex interplay between host genetic, immunological and viral factors. This review highlights genes involved in innate and adaptive immune responses associated with different outcomes of HCV infection. For example, an association of HCV clearance with certain HLA alleles has been demonstrated. The mechanisms responsible for these associations have been linked to specific T cell responses for some particular alleles (e.g., HLA-B27). Genetic associations involved in T cell regulation and function further underline the role of the adaptive immune response in the natural history of HCV infection. In addition, some genes involved in innate NK cell responses demonstrate the complex interplay between components of the immune system necessary for a successful host response to HCV infection.

Antiviral therapy after complete response to chemotherapy could be efficacious in HCV-positive non-Hodgkin's lymphoma

BACKGROUND/AIMS

Prevalence of HCV infection in non-Hodgkin's lymphoma is high. The impact of antiviral therapy on the natural history of this subgroup of lymphomas after a successful chemotherapy regimen is still an argument of debate.

METHODS

We retrospectively examined 343 chemotherapy-treated patients referred to our centre for five consecutive years. Clinical and histological characteristics, disease free-survival (DFS) and overall-survival (OS) were compared in HCV-positive (69/343) and HCV-negative (274/343) patients. Twenty-five HCV-positive patients received antiviral treatment following chemotherapy discontinuation. Uni- and multivariate analyses were performed.

RESULTS

20% of lymphomas were HCV-positive. Indolent histology was prevalent in the HCV-positive group (p<0.05); no significant differences in OS or DFS were found between the two groups; in HCV-positive subjects, antiviral therapy, was associated with a longer DFS (p<0.05); none of the HCV-positive subjects who achieved a virological response experienced any lymphoma relapse; 29% of non responders did; at multivariate analysis, the independent factors related to a better clinical outcome were: indolent histology at the onset of lymphoma and antiviral therapy.

CONCLUSIONS

Antiviral treatment in HCV-positive non-Hodgkin's lymphoma may be an important strategy to reinforce the results of a successful chemotherapy regimen; further studies are needed to validate this combined approach.

Analysis of IL-10, IL-4 and TNF-alpha polymorphisms in drug-induced liver injury (DILI) and its outcome

BACKGROUND/AIMS

The aim of this study was to assess whether genetic polymorphism of three important candidate cytokine genes, IL-10 (-1082G/A, -819C/T, and -592C/A), IL-4 (-590C/T) and TNF-alpha (-308G/A), play a role in the susceptibility to developing drug-induced liver injury (DILI), and in determining its phenotypic expression and severity.

METHODS

Cytokine genotyping was analysed using TaqMan 5' allelic discrimination assay in 140 DILI patients (mean age 51 y, range 13-82, with equal sex distribution) included in the Spanish Registry and 268 healthy controls.

RESULTS

Genotypes, haplotypes and allele frequencies were similar for both cases and controls. The low IL-10 producing haplotype was more prevalent in DILI patients with the absence of peripheral blood eosinophilia (Pc=0.004, OR=5.29, 95% CI: 2.04-13.67), revealing significantly lower median eosinophil counts (0.19 x 10(9)L; P<0.0002) compared to the intermediate (0.24 x 10(9)L) and high (0.40 x 10(9)L) IL-10 haplotypes. All cases with serious DILI outcome carried low or intermediate IL-10 producing haplotype and had normal or low eosinophil counts.

CONCLUSIONS

IL-10, IL-4 and TNF-alpha genetic polymorphisms were not related to the risk of developing DILI. Low IL-10 producing haplotype is associated with low eosinophil count, absence of eosinophilia and may be associated with worse clinical outcome from DILI.

Hepatitis C virus: from oxygen free radicals to hepatocellular carcinoma

Epidemiological evidence clearly identifies chronic infection with hepatitis C virus (HCV) as a major risk factor for the development of hepatocellular carcinoma (HCC). Among the mechanisms that have been implicated in the pro-carcinogenic effect of HCV infection, an increased production of reactive oxygen species in the liver seems to have a major pathogenetic role in leading from chronic inflammation to cancer. Recent data have also demonstrated that HCV is capable of inducing this active production of free radicals per se, not just through inflammation, a feature peculiar to this virus and the specific activity of its core protein. This paper provides an overview of the inter-relationships between HCV, liver damage, free radical production and HCC, describing at least in part the complex network involving DNA oxidative damage, cytokine synthesis, proto-oncogene activation and oestrogen receptor expression, that may all be deeply involved in liver carcinogenesis.

IL-10, T cell exhaustion and viral persistence

Viral infections can have one of two outcomes: control of viral replication and acute infection or viral persistence and chronic infection. It is clear that both pathogen and host characteristics influence the acute versus chronic outcome of viral infection. The early events in the host immune response that favor immunosuppression and viral persistence, however, have remained poorly understood. Using the well-characterized mouse model of acute versus chronic lymphocytic choriomeningitis virus (LCMV) infection, two groups have recently identified the interleukin-10 (IL-10)/IL-10R pathway as a key regulator of acute versus chronic infection. Blockade of IL-10R converted a chronic LCMV infection into a rapidly controlled acute viral infection and prevented the functional exhaustion of memory T cells. These insights into the role of IL-10 in the establishment of chronic infection could lead to new therapeutic opportunities during human infections with pathogens such as HIV, hepatitis C virus (HCV) and hepatitis B virus (HBV).