IL-18 polymorphisms in hepatitis B virus related liver disease

An HBV susceptibility variant of KNG1 modulates the therapeutic effects of interferons α and λ1 in HBV infection by promoting MAVS lysosomal degradation

BACKGROUND

Hepatitis B virus (HBV) infection is one of the main causes of hepatocellular carcinoma (HCC). The relationship between HBV infection and the host genome as well as their underlying mechanisms remain largely unknown.

METHODS

In this study, we performed a whole-genome exon sequencing analysis of 300 sib-pairs of Chinese HBV-infected families with the goal of identifying variants and genes involved in HBV infection. A site-direct mutant plasmid was used to investigate the function of SNP rs76438938 in KNG1. The functional and mechanical studies of KNG1 were conducted with in vitro liver cell lines and a hydrodynamic injection model in vivo. The impact of KNG1 on HBV infection therapy was determined in hepatocytes treated with IFN-α/λ1.

FINDINGS

Our whole-exon association study of 300 families with hepatitis B infection found that SNP rs76438938 in KNG1 significantly increased the risk for HBV infection, and the rs76438938-T allele was found to promote HBV replication by increasing the stability of KNG1 mRNA. By competitively binding HSP90A with MAVS, KNG1 can inhibit the expression of types I and III IFNs by promoting MAVS lysosomal degradation. Such suppression of IFN expression and promotion of HBV replication by Kng1 were further demonstrated with an animal model in vivo. Lastly, we showed that the rs76438938-C allele can improve the therapeutic effect of IFN-α and -λ1 in HBV infection.

INTERPRETATION

This study identified a SNP, rs76438938, in a newly discovered host gene, KNG1, for its involvement in HBV infection and treatment effect through modulating the cellular antiviral process.

FUNDING

This study was supported in part by the Independent Task of State Key Laboratory for Diagnosis and Treatment of Infectious Diseases of the First Affiliated Hospital of Zhejiang University, the China Precision Medicine Initiative (2016YFC0906300), and the Research Center for Air Pollution and Health of Zhejiang University.

Ct, IL-18 polymorphism, and laboratory biomarkers for predicting chemosensory dysfunctions and mortality in COVID-19

Aim

Patients with COVID-19 often experience chemosensory dysfunction. This research intends to uncover the association of RT-PCR Ct value with chemosensory dysfunctions and SpO2. This study also aims to investigate Ct, SpO2, CRP, D-dimer, and -607 IL-18 T/G polymorphism in order to find out predictors of chemosensory dysfunctions and mortality.

Materials & methods

This study included 120 COVID-19 patients, of which 54 were mild, 40 were severe and 26 were critical. CRP, D-dimer, RT-PCR, and IL-18 polymorphism were evaluated. Results & conclusion: Low Ct was associated with SpO2 dropping and chemosensory dysfunctions. IL-18 T/G polymorphism did not show an association with COVID-19 mortality; conversely, age, BMI, D-dimer and Ct values did.

Heterogeneity of immune control in chronic hepatitis B virus infection: Clinical implications on immunity with interferon-α treatment and retreatment

Hepatitis B virus (HBV) infection is a global public health issue. Interferon-α (IFN-α) treatment has been used to treat hepatitis B for over 20 years, but fewer than 5% of Asians receiving IFN-α treatment achieve functional cure. Thus, IFN-α retreatment has been introduced to enhance antiviral function. In recent years, immune-related studies have found that the complex interactions between immune cells and cytokines could modulate immune response networks, in-cluding both innate and adaptive immunity, triggering immune responses that control HBV replication. However, heterogeneity of the immune system to control HBV infection, particularly HBV-specific CD8⁺ T cell heterogeneity, has consequ-ential effects on T cell-based immunotherapy for treating HBV infection. Altogether, the host’s genetic variants, negative-feedback regulators and HBV components affecting the immune system's ability to control HBV. In this study, we reviewed the literature on potential immune mechanisms affecting the immune control of HBV and the clinical effects of IFN-α treatment and retreatment.

Host Factors in the Natural History of Chronic Hepatitis B: Role of Genetic Determinants

BACKGROUND

The host immune system plays an important role in hepatitis B virus (HBV) infection manifestation. Genetic polymorphisms of several inflammatory cytokines, including TNF-α and IL-10, have been associated with chronic hepatitis B (CHB) progression, although with contradicting results. CHB progression can be categorized into four phases, immune tolerance (IT), immune clearance (IC), low/no replicative (LR), and e-negative hepatitis (ENH), with HBeAg seroconversion as an important milestone. Here, we determined the association of TNF-α (rs1800629) and IL-10 (rs1800896 and rs1800872) SNPs in the context of CHB natural history progression, particularly to HBeAg seroconversion, in Indonesian CHB patients.

METHODS

A total of 287 subjects were recruited and categorized into distinct CHB phases based on HBeAg, viral load, and ALT levels. TNF-α and IL-10 SNPs were determined using PCR-RFLP and confirmed with direct sequencing. The association between SNP genotypes with CHB dynamics was determined using logistic regression presented as odds ratio (OR) with 95% CI.

RESULTS

No significant association was found between IL-10 -592A/C polymorphism and progression of IT and IC to LR, IT and IC to ENH, and LR to ENH phases in all the gene models. IL-10 rs1800896 and TNF-α rs1800629 could not be analyzed using logistic regression. Subjects' age (≥40 years old) was significantly associated with IT and IC to LR (OR: 2.191, 95% CI 1.067-4.578, P = 0.034), IT and IC to ENH (OR: 7.460, 95% CI 3.316-18.310, P < 0.001), and LR to ENH (OR: 5.252, 95% CI 2.010-14.858, P = 0.001). Male gender was associated with LR to ENH (OR: 4.077, 95% CI 1.605-11.023, P = 0.004).

CONCLUSIONS

Age and male gender were associated with CHB phase progression instead of the TNF-α and IL-10 polymorphisms. It would be beneficial to study not only the effect of host determinants but also the viral factor to understand the mechanisms of CHB phase progression.

Genetic associations in chronic hepatitis B infection: toward developing polygenic risk scores

Chronic hepatitis B (CHB) infection results in multiple clinical phenotypes of varying severity. One of the critical gaps in CHB management is the lack of a genetic-based tool to aid existing hepatocellular carcinoma and cirrhosis risk stratification models for patients with active CHB. Such individual predictive models for CHB are plagued by an inherent limitation of discriminatory power that clearly indicates the need for their improvement. In this article, we highlight genetic association studies in CHB that identified HLA and cytokine genetic susceptibility loci to CHB. We advance the position that translating CHB genetic susceptibility loci into polygenic risk scores will be a welcome addendum to the current arsenal of CHB outcome predictive models. We conclude with comments on hurdles that future research efforts should address within the research enclave of CHB and advocate for increased genetic data representation from sub-Saharan Africa.

Human genetic susceptibility to hepatitis B virus infection

Hepatitis B virus (HBV) infection is still a serious health threat worldwide. The outcomes of HBV infection consist of spontaneous HBV clearance and chronic HBV infection. Multiple factors contribute to the disparity of HBV infection outcomes, including host factors, viral factors and environmental factors. The present review comprehends the current researches mainly focusing on the relationships between genetic determinants, including single nucleotide polymorphisms (SNPs) and haplotypes, and susceptibility of HBV infection, namely chronic (persistent) HBV infection and HBV clearance. A number of determinants in the chromosomes, including mutations in human leukocyte antigens (HLAs), cytokines genes, toll-like receptors (TLRs), and other genes are related to the human susceptibility to HBV infection. Among the above variants, some of those in HLAs have been studied and replicated in multiple-ethnic populations and came to consistent conclusions, while some others are novel and need to be evaluated further.

Polymorphism in the Promoter Region of the IL18 Gene and the Association With Severity on Paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is an important endemic, systemic disease in Latin America caused by Paracoccidioides spp. This mycosis has been associated with high morbidity and sequels, and its clinical manifestations depend on the virulence of the infecting strain, the degree and type of immune response, infected tissues, and intrinsic characteristics of the host. The T helper(Th)1 and Th17/Th22 cells are related to resistance and control of infection, and a Th2/Th9 response is associated with disease susceptibility. In this study, we focused on interleukin(IL)-12p35 (IL12A), IL-18 (IL18), and IFN-γ receptor 1 (IFNGR1) genetic polymorphisms because their respective roles have been described in human PCM. Real-time PCR was employed to analyze IL12A-504 G/T (rs2243115), IL18-607 C/A (rs1946518), and IFNGR1-611 A/G (rs1327474) single nucleotide polymorphisms (SNP). One hundred forty-nine patients with the acute form (AF), multifocal chronic (MC), or unifocal chronic (UC) forms of PCM and 110 non-PCM individuals as a control group were included. In the unconditional logistic regression analysis adjusted by ethnicity and sex, we observed a high risk of the IL18-607 A-allele for both AF [p = 0.015; OR = 3.10 (95% CI: 1.24–7.77)] and MC groups [p = 0.023; OR = 2.61 (95% CI: 1.14–5.96)] when compared with UC. The IL18-607 A-allele associated risk for the AF and MC groups as well as the protective role of the C-allele in UC are possibly linked to higher levels of IL-18 at different periods of the course of the disease. Therefore, a novel role of IL18-607 C/A SNP is shown in the present study, highlighting its importance in the outcome of PCM.

Genotyping of immune-related loci associated with delayed HBeAg seroconversion in immune-active chronic hepatitis B patients

The progression of chronic hepatitis B (CHB) is associated with single-nucleotide polymorphisms (SNPs). In this study, we demonstrated the association between immune-related SNPs and delayed spontaneous HBeAg seroconversion in immune-active CHB patients. In addition, we investigated the impact of delayed spontaneous HBeAg seroconversion-related SNPs on HBeAg seroconversion within 3 years during antiviral treatment. We enrolled 332 CHB patients and genotyped 124 SNPs associated with HBV-infected clinical outcomes, including 32 interleukin-related genes, 62 HLA genes, 9 CD marker genes, 7 NK cell receptor genes, and 14 other genes, using ABI OpenArray as a platform. Comparing the immune-active CHB patients with delayed spontaneous HBeAg seroconversion (persistent HBeAg seropositivity, older than 40 years) to those with early inefficient HBeAg seroconversion (HBeAg seroconversion with high viremia, younger than 40 years), logistic analysis revealed that rs3820998 (TANK), rs2621377 (HLA-DOB), rs3130215 (HLA-DPB2), rs2255336 (KLRK1), and rs11614913 (MIR-196A2) were significantly associated with delayed spontaneous HBeAg seroconversion. Using multivariate analysis, we determined that high serum HBV DNA levels (OR = 1.66, 95% CI = 1.33-2.08), rs3820998 (CA, OR = 3.37, 95% CI = 1.24-9.12), rs2621377 (TC, OR = 4.96, 95% CI = 1.85-13.3), rs2255336 (TT, OR = 0.09, 95% CI = 0.01-0.86), and rs11614913 (TT, OR = 2.53, 95% CI = 1.05-6.11) were five independent risk factors for delayed spontaneous HBeAg seroconversion. After patients received nucleos(t)ide analogue treatment, rs3820998 heterozygous CA variant conversely became the only independent favorable factor for treatment-induced HBeAg seroconversion within 3 years (OR = 0.21, 95% CI = 0.06-0.78). These results indicate that distinct immune-related SNPs play a vital role in regulating HBeAg status in immune-active CHB patients with or without antiviral treatment.

A comprehensive evaluation of single nucleotide polymorphisms associated with hepatocellular carcinoma risk in Asian populations: A systematic review and network meta-analysis

BACKGROUND

Single nucleotide polymorphisms (SNPs) have been inconsistently associated with hepatocellular carcinoma (HCC) risk. This meta-analysis aimed to synthesize relevant data on SNPs associated with HCC in the Asian population.

METHODS

Databases were searched to identify association studies of SNPs and HCC in Asians published through January 2019. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated based on 41 studies (13,167 patients with HCC and 15,886 noncancer controls). Network meta-analysis and Thakkinstian's algorithm were used to select the most appropriate genetic model, along with false positive report probability (FPRP) for noteworthy associations.

RESULTS

Eleven SNPs meeting the inclusion criteria were tested for association with HCC, including CCND1 rs9344, PTGS2 rs689466, IL18 rs187238 and rs1946518, KIF1B rs17401966, MDM2 rs2279744, MIR146A rs2910164, MIR149 rs2292832, MIR196A2 rs11614913, MIR499A rs3746444, and TGFB1 rs1800469. A significant increase for HCC risk was observed for MDM2 rs2279744, and the dominant (pooled OR = 1.59, 95% CI: 1.26-2.00) and codominant (pooled OR = 1.37, 95% CI: 1.18-1.60) models were determined to be the most appropriate models. MIR499A rs3746444 also showed a significant association with HCC risk under the allele contrast model (pooled OR = 1.36, 95% CI: 1.05-1.77). Only the significance of MDM2 rs2279744 was noteworthy (FPRP < 0.2).

CONCLUSIONS

MDM2 rs2279744 is associated with HCC susceptibility in Asians, and the dominant and codominant models are likely the most appropriate models to estimate HCC risk.

Associations between twelve common gene polymorphisms and susceptibility to hepatocellular carcinoma: evidence from a meta-analysis

Background

Associations between polymorphisms in vitamin D receptor (VDR)/vascular endothelial growth factor (VEGF)/interleukin-18 (IL-18)/mannose-binding lectin (MBL) and susceptibility to hepatocellular carcinoma (HCC) were already explored by many studies, yet the results of these studies were inconsistent. The aim of this meta-analysis was to better clarify associations between polymorphisms in VDR/VEGF/IL-18/MBL and HCC by combing the results of all relevant studies.

Methods

Eligible publications were searched from PubMed, Embase, WOS, and CNKI. We used Review Manager to combine the results of individual studies.

Results

Thirty studies were included in this study. Combined results revealed that VDR rs7975232, VDR rs2228570, VEGF rs699947, VEGF rs3025039, IL-18 rs1946518, and MBL rs7096206 polymorphisms were all significantly associated with HCC in the overall pooled population. We also obtained similar significant associations for VDR rs7975232, VDR rs2228570, IL-18 rs1946518, and MBL rs7096206 polymorphisms in Asians.

Conclusions

Collectively, this meta-analysis proved that VDR rs7975232, VDR rs2228570, VEGF rs699947, VEGF rs3025039, IL-18 rs1946518, and MBL rs7096206 polymorphisms may confer susceptibility to HCC in certain populations.

Frequency of Interleukins IL1ß/IL18 and Inflammasome NLRP1/NLRP3 Polymorphisms in Sickle Cell Anemia Patients and their Association with Severity Score

BACKGROUND

Interleukins IL1ß/IL18 and Inflammasome NLRP1/NLRP3 polymorphisms can change the course of multiple human diseases, both inflammatory as infectious. SNPs these proteins were associated with the constructive activation of the Inflammasome and excessive production of IL-1β induce a serious autoinflammatory disease, as sickle cell anemia (SCA). The present study aims to association of interleukins IL1ß/IL18 and inflammasome NLRP1/NLRP3 polymorphisms in SCA patients in Amazon region and their association with severity score.

METHODS

The study was developed at Fundação Hospitalar de Hematologia e Hemoterapia do Amazonas (HEMOAM) with 21 patients diagnosed SCA (HbSS) and 50 Healthy Donor´s. Genetic polymorphisms (SNPs) in interleukins IL1ß/IL18 and inflammasome NLRP1/NLRP3 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and real time PCR. Simple and multiple logistic regression were performed to investigate association between the polymorphisms and the SCA and severe score.

RESULTS

The genotypes C/C (IL18 -137G/C) and C/A (NLRP3, rs35829419) appear to be risk factors for SCA disease (IL18: G/G vs C/C OR=103.500 [95% CI: 8.32-1287.79, p<0.00001]; IL18: G/G vs G/C OR=7.360 [95% CI: 0.85-63.48, p=0.040]; IL18: G/G vs CC+CG OR=14.481 [95% CI: 1.79-117.32, p=0.002; NLRP3: C/C vs C/A: OR=10.967 [95% CI: 2.41-49.89, p=0.0004]). In addition, only allelic C (IL18 -137G/C) and A (NLRP3) appear to be risk factors for SCA disease (IL18: G vs C OR=6.366 [95% CI: 2.73-14.86, p<0.00001]; NLRP3: C vs A OR=8.383 [95% CI: 2.03-34.62, p=0.005]. No associations were observed between genotypes and alleles with the severity score.

CONCLUSION

Evidence of association between the IL18 (rs16944) and NLRP3 (rs35829419) polymorphisms with sickle cell anemia were described. Our results suggest that individuals with genotypes evaluated are associated SCA disease even though it does not influence the severe score.

Host Genetic Determinants of Hepatitis B Virus Infection

Chronic hepatitis B virus (HBV) infection is still a major health problem worldwide. Recently, a great number of genetic studies based on single nucleotide polymorphisms (SNPs) and genome-wide association studies have been performed to search for host determinants of the development of chronic HBV infection, clinical outcomes, therapeutic efficacy, and responses to hepatitis B vaccines, with a focus on human leukocyte antigens (HLA), cytokine genes, and toll-like receptors. In addition to SNPs, gene insertions/deletions and copy number variants are associated with infection. However, conflicting results have been obtained. In the present review, we summarize the current state of research on host genetic factors and chronic HBV infection, its clinical type, therapies, and hepatitis B vaccine responses and classify published results according to their reliability. The potential roles of host genetic determinants of chronic HBV infection identified in these studies and their clinical significance are discussed. In particular, HLAs were relevant for HBV infection and pathogenesis. Finally, we highlight the need for additional studies with large sample sizes, well-matched study designs, appropriate statistical methods, and validation in multiple populations to improve the treatment of HBV infection.

IL-18 and IL-1β Gene Polymorphisms: The Plausible Risk Factors for Chronic Hepatitis B

Chronic inflammation is the main risk factor for induction of liver cirrhosis and also hepatocellular carcinoma in chronic hepatitis B (CHB) patients. Although our knowledge is growing regarding molecular mechanisms of immune responses against viruses, the main mechanisms that lead to the progression of chronic inflammation and then CHB are yet to be clarified. IL-18 and IL-1β are the members of the IL-1 family and produced in the cytoplasm of a wide range of immune and nonimmune cells and activated by inflammasome pathways. The cytokines play key roles in the pathologies of CHB. IL-18 and IL-1β productions are altered in CHB patients. It has been hypothesized that the polymorphisms within IL-18 and IL-1β genes may be the main reasons for the induction of chronic inflammation in CHB patients. This review article discusses the related investigations regarding the main correlation between the polymorphisms within IL-18 and IL-1β genes and CHB pathogenesis.

Systematic Review and Meta-Analysis on the Association between Polymorphisms in Genes of IL-12 Signaling Pathway and Hepatocellular Carcinoma Risk

We performed an updated meta-analysis and systematic review to explore the associations between polymorphisms in genes of IL-12 signaling pathway and hepatocellular carcinoma (HCC) risk. Diverse databases were retrieved to identify entire available studies, and odds ratios (ORs) correspondence with 95% confidence intervals (CIs) were performed to assess their associations. Finally, 6 polymorphisms in five genes of the IL-12 signaling pathway were extracted from 39 case-control studies, 26 publications. We identified that STAT4-rs7574865 polymorphism was significantly associated with an increased risk of HCC in allelic contrast, dominant, homozygote and recessive models. However, we failed to uncover any significant association between other polymorphisms in genes of IL-12 signaling pathway and HCC risk, including IL18-rs1946518 and -rs187238, IFN-γ-rs2430561, IL12A-rs568408, IL12B-rs3212227 and STAT4-rs7574865. When the subgroup analysis was conducted based on Hardy-Weinberg Equilibrium (HWE) status, we identified that IFN-γ-rs2430561 polymorphism was significantly associated with an increased risk of HCC in homozygote and recessive models of these studies whose control groups were conformed to HWE. To sum up, our study suggests that STAT4-rs7574865 is a risk factor for HCC. Further well-designed large sample size studies are warranted to shed new light on these findings.

Associations of human leukocyte antigen and interleukin-18 gene polymorphisms with viral load in patients with hepatitis B infection

This study aimed to assess the associations of human leukocyte antigen (HLA)-DR and interleukin (IL)-18 gene polymorphisms with hepatitis B virus (HBV).Clinical data were retrospectively reviewed between December 2006 and December 2015 at Xiangyang Central Hospital. HBV patients were assigned to the high and low viral load groups, respectively, according to HBV copies. HLA-DRB1*03 polymorphisms and IL-18 polymorphisms were detected by sequence-specific primer-polymerase chain reaction (PCR-SSP) and PCR-ligase detection reaction (PCR-LDR), respectively. T cell subgroups were identified by flow cytometry, and IL-18, IL-12, interferon-γ (IFN-γ), IL-4, and IL-10 expression levels were assessed by ELISA. A total of 630 subjects were included in the analysis.Compared with healthy controls, the chronic HBV group showed significantly lower IL-18 (P < .001), IL-12 (P < .001), and IFN-γ (P < .001) expression levels, and markedly increased IL-4 (P < .001) and IL-10 (P < .001) amounts. Th2 cytokine expression was high in HLA-DRB1*03 positive (+) HBV patients, with low Th1 cytokine levels. The ratios of CD4+/CD8+ and Th1/Th2 cells decreased with increasing HBV DNA levels. The chronic HBV group showed a relatively high frequency of -137G in the IL-18 gene, while IL-18 expression was low in homozygous GG genotype individuals.Polymorphisms in the HLA-DRB1*03 and IL-18 genes are associated with viral load in HBV. HLA-DRB1 and IL-18 gene polymorphisms are involved in the regulation of the Th1/Th2 balance and expression of relevant cytokines that influence immune responses in HBV.

Correlation between cortisol levels and concurrent infection for hepatitis B cirrhosis patients and countermeasure analysis

The study assessed the correlation between cortisol (COR) levels and concurrent infection for the patients with hepatitis B cirrhosis for corresponding countermeasure analysis. In total, 86 patients with hepatitis B cirrhosis (non-infection group) and 32 patients with hepatitis B cirrhosis complicated with infection (infection group) who were diagnosed and treated in the Beijing YouAn Hospital from March 2014 to March 2017 were selected. The fasting venous blood of all the patients was drawn to detect COR, cortisol binding globulin (CBG), blood routine indexes, C-reactive protein (CRP), procalcitonin (PCT), endotoxin and other indicators. The relative expression of CBG mRNA was detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR). The differences and correlation of COR levels between the infection and non-infection groups were compared and analyzed. The concentrations of COR and CBG were decreased with the increase of Child-Pugh grade, and the difference was statistically significant (P<0.05). COR, CBG and free cortisol (FC) concentrations with the same Child-Pugh grade in the non-infection group were higher than those in the infection group (P<0.05). COR, CBG and FC concentrations of abdominal infection complicated with sepsis or abdominal infection complicated with pulmonary infection were lower than those of simple abdominal infection (P<0.05). The relative expression of CBG mRNA was detected by RT-qPCR, which also showed that: for Child-Pugh grade, grade A > grade B > grade C (P<0.05), non-infection group > infection group (P<0.05), abdominal infection + sepsis group and abdominal infection + pulmonary infection group were lower than the simple abdominal infection group (P<0.05). The values of white blood cells (WBC), neutrophils, CRP, PCT and endotoxin in the infection group were higher than those in the non-infection group, and the differences were statistically significant (P<0.05). COR, CGB and FC were negatively correlated with inflammatory indexes such as WBC, neutrophils, CRP, PCT and endotoxin. The r value of COR and FC in the non-infection group was 0.678, while that of OR and FC in the infection group was 0.787. COR was positively correlated with FC before and after infection. The results of the study show that the cortisol levels of patients with hepatitis B cirrhosis are significantly correlated with whether infected or not, levels of disease condition and infection types, and can be used as sensitive indicators of hepatitis B cirrhosis infection.

Association of genetic variants in the interleukin-18 gene promoter with risk of hepatocellular carcinoma and metastasis in patients with hepatitis C virus infection

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver, characterized by high vascularization and rapid tumor progression. The current case-control study aimed to analyze the influence of -607C/A and -137G/C polymorphisms in the interleukin-18 (IL-18) promoter on the risk of HCC occurrence and metastasis in Egyptian patients infected with hepatitis C virus (HCV). Both genetic variations were genotyped in 279 subjects including HCV patients with and without HCC and unrelated healthy subjects, using the allele-specific polymerase chain reaction (AS-PCR) method. The relationship between clinico-laboratory parameters including serum level of alpha-fetoprotein (AFP) and these polymorphisms was evaluated in HCC patients. The IL-18-607A allele and AA genotype were significantly related to a higher risk of developing HCC when comparing patients with HCC and controls, and were significantly related to a higher risk of metastasis when comparing metastatic and nonmetastatic groups in the Egyptian patients. In contrast, the IL18-137C allele and GC genotype were significantly related to a lower risk of developing HCC when comparing patients with HCC and controls, and HCV patients with and without HCC. A significant association was found between multinodular HCC and IL-18-607AA genotype, while, uninodular HCC was significantly associated with IL-18-137GG genotype. In addition, IL18-607AA and -137GG genotypes showed significant association with higher level of serum AFP. The detection of polymorphisms in the IL-18 promoter, in a combination with an evaluation of level of serum AFP, could be used as a molecular biomarker in the early diagnosis of HCC, which would aid the early management of the disease, thus decreasing the rate of mortality of this disease. © 2018 IUBMB Life, 70(2):165-174, 2018.

IL-18 Drives ILC3 Proliferation and Promotes IL-22 Production via NF-κB

Group 3 innate lymphoid cells (ILC3s) are important regulators of the immune system, maintaining homeostasis in the presence of commensal bacteria, but activating immune defenses in response to microbial pathogens. ILC3s are a robust source of IL-22, a cytokine critical for stimulating the antimicrobial response. We sought to identify cytokines that can promote proliferation and induce or maintain IL-22 production by ILC3s and determine a molecular mechanism for this process. We identified IL-18 as a cytokine that cooperates with an ILC3 survival factor, IL-15, to induce proliferation of human ILC3s, as well as induce and maintain IL-22 production. To determine a mechanism of action, we examined the NF-κB pathway, which is activated by IL-18 signaling. We found that the NF-κB complex signaling component, p65, binds to the proximal region of the IL22 promoter and promotes transcriptional activity. Finally, we observed that CD11c+ dendritic cells expressing IL-18 are found in close proximity to ILC3s in human tonsils in situ. Therefore, we identify a new mechanism by which human ILC3s proliferate and produce IL-22, and identify NF-κB as a potential therapeutic target to be considered in pathologic states characterized by overproduction of IL-18 and/or IL-22.

IL-18 polymorphisms contribute to hepatitis B virus-related cirrhosis and hepatocellular carcinoma susceptibility in Chinese population: a case-control study

IL-18 polymorphisms influence the transcriptional activity of the IL-18 gene and associated with various diseases. However, their relationships with hepatitis B virus-related liver diseases had not reached a consensus. So we conducted this case-control study with a view to clarifying the association. We included four groups: healthy controls, chronic hepatitis B virus (CHB) carriers, liver cirrhosis (LC) and hepatocellular carcinoma (HCC) groups with each group of 250 persons. Odd ratios (ORs) and 95% confidence intervals (95%CIs) with or without adjustment were calculated. Haplotype analysis was also performed. The results showed people carrying rs187238 CG genotype had a lower risk of LC (CG vs. CC: OR = 0.59, 95%CI = 0.38–0.91, P = 0.02), while GG genotype carriers had a higher risk of HCC (GG vs. CC+CG: OR = 4.73, 95%CI = 1.01–22.1, P = 0.03) than those with CC and CG genotypes in healthy group. Rs187238 GG genotype increased the risk from CHB to LC status (GG vs. CC: OR = 4.81, 95%CI = 1.03–22.6; GG vs. CC+CG: OR = 4.73, 95%CI = 1.01–22.1), meanwhile the trend also existed by controlling confounding factors (GG vs. CC: OR = 6.25, 95%CI = 1.09–35.8; GG vs. CC+CG: OR = 5.91, 95%CI = 1.04–33.7). Haplotype Crs187238Trs1946518 moderately decreased the risk of CHB carriers developing into HCC (OR = 0.69, 95%CI = 0.50–0.96, P = 0.03) after adjustment. In conclusion, IL-18 rs187238 GG genotype may increase the risk of HCC in healthy population and the risk of LC in CHB carriers.

Association Between the Telomerase rs2736098_TT Genotype and a Lower Risk of Chronic Hepatitis B and Cirrhosis in Chinese Males

OBJECTIVES

Chronic hepatitis B (CHB) is caused by infection of hepatitis B virus (HBV) and liver cirrhosis (LC) is its most common complication. The accumulated evidence indicates a genetic context of HBV infection phenotypes. Here we determine a potential association of CHB/LC with the genetic variant of telomerase reverse transcriptase (TERT), a key player in aging including immune-senescence.

METHODS

The study included 227 Chinese CHB patients and 315 sex/age-matched healthy controls. TERT rs2736098 and rs2736100 genotyping was performed using pre-designed TaqMan SNP genotyping assay kits. Leukocyte telomere length (LTL) was determined using quantitative PCR.

RESULTS

The rs2736098_CT/CC genotypes were significantly associated with risk of CHB compared to the TT one (OR 2.265, 95% CI 1.202-4.269, P=0.015). A similar association was also found in CHB patients with cirrhosis (CT/CC vs TT: OR 2.398, 95% CI 1.168-4.922, P=0.02). Further analyses showed that the rs2736098_TT genotype difference occurred between male controls and patients (P=0.008) and male CT/CC-carriers exhibited highly increased risk of CHB compared to male controls (CT+CC vs TT, OR 3.182, 95% CI 1.350-7.500, P=0.01). There was no difference in the rs2736100 variants between controls and CHB patients. LTL was not different between cases and controls.

CONCLUSIONS

The TERT rs2736098_TT genotype is associated with a lower CHB and LC risk in Chinese males, which may have implications in CHB pathogenesis and prevention.

Association between TLR7 copy number variations and hepatitis B virus infection outcome in Chinese

AIM

To explore whether copy number variations (CNVs) of toll-like receptor 7 (TLR7) are associated with susceptibility to chronic hepatitis B virus (HBV) infection.

METHODS

This study included 623 patients (495 males and 128 females) with chronic hepatitis B virus infection (CHB) and 300 patients (135 females and 165 males) with acute hepatitis B virus infection (AHB) as controls. All CHB patients were further categorized according to disease progression after HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). Copy numbers of the TLR7 gene were measured using the AccuCopy method. χ² tests were used to evaluate the association between TLR7 CNVs and infection type. P values, odds ratios, and 95% confidence intervals (CIs) were used to estimate the effects of risk.

RESULTS

Among male patients, there were significant differences between the AHB group and CHB group in the distribution of TLR7 CNVs. Low copy number of TLR7 was significantly associated with chronic HBV infection (OR = 0.329, 95%CI: 0.229-0.473, P < 0.001). Difference in TLR7 copy number was also found between AHB and CHB female patients, with low copy number again associated with an increased risk of chronic HBV infection (OR = 0.292, 95%CI: 0.173-0.492, P < 0.001). However, there were no significant differences in TLR7 copy number among the three types of chronic HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). In addition, there was no association between TLR7 copy number and titer of the HBV e antigen.

CONCLUSION

Low TLR7 copy number is a risk factor for chronic HBV infection but is not associated with later stages of disease progression.

Genetic polymorphisms -137 (rs187238) and -607 (rs1946518) in the interleukin-18 promoter may not be associated with development of hepatocellular carcinoma

This study meta-analyzed the literature on possible association of polymorphisms -137 (rs187238) and -607 (rs1946518) in the interleukin-18 (IL-18) promoter with risk of hepatocellular carcinoma (HCC). The analysis included 8 case-control studies on the -137 polymorphism (1,318 cases, 2,254 controls) and 7 case-control studies on the -607 polymorphism (1,262 cases, 1,696 controls). None of the five genetic models suggested a significant association between the -137 polymorphism and HCC risk: allelic model, OR 0.99, 95% CI 0.74-1.34, P = 0.97; recessive model, OR 0.98, 95% CI 0.65-1.46, P = 0.91; dominant model, OR 1.35, 95% CI 0.73-2.52, P = 0.34; homozygous model, OR 0.99, 95% CI 0.65-1.49, P = 0.95; heterozygous model, OR 0.99, 95% CI 0.66-1.48, P = 0.94. Similar results were obtained in subgroup analyses of Asian patients, Chinese patients, or patients with hepatitis B virus (HBV)-related HCC. Similar results were also obtained for the -607 polymorphism across the entire study population as well as in the three subgroups. The available evidence suggests no significant association of the -137 or -607 polymorphisms with risk of HCC in general or specifically of HBV-related HCC. These conclusions should be verified in large, well-designed studies.

Hepatitis-related hepatocellular carcinoma: Insights into cytokine gene polymorphisms

Hepatocellular carcinoma (HCC) is a primary liver cancer, which is one of the most prevalent cancers among humans. Many factors are involved in the liver carcinogenesis as lifestyle and environmental factors. Hepatitis virus infections are now recognized as the chief etiology of HCC; however, the precise mechanism is still enigmatic till now. The inflammation triggered by the cytokine-mediated immune response, was reported to be the closest factor of HCC development. Cytokines are immunoregulatory proteins produced by immune cells, functioning as orchestrators of the immune response. Genes of cytokines and their receptors are known to be polymorphic, which give rise to variations in their genes. These variations have a great impact on the expression levels of the secreted cytokines. Therefore, cytokine gene polymorphisms are involved in the molecular mechanisms of several diseases. This piece of work aims to shed much light on the role of cytokine gene polymorphisms as genetic host factor in hepatitis related HCC.

Role of IL-18 Gene Promoter Polymorphisms, Serum IL-18 Levels, and Risk of Hepatitis B Virus-related Liver Disease in the Guangxi Zhuang Population: a Retrospective Case-Control Study

BACKGROUND

The aim of this study was to assess the relationship between IL-18 gene polymorphisms and HBV-related diseases and whether these polymorphisms influence its expression in the Guangxi Zhuang population.

MATERIALS AND METHODS

We enrolled 129 chronic HBV infected (CHB) patients, 86 HBV-related liver cirrhosis (LC) patients and 160 healthy controls in our study. Polymerase chain reaction-restriction fragment length polymorphism methods were used to detect IL-18 gene -607C/A, -137G/C polymorphisms, and an ELISA kit was employed to determine serum IL-18 levels.

RESULTS

No correlation was found between the -607C/A polymorphism and risk of HBV-related disease. For the -137G/C polymorphism, the GC genotype and C allele were associated with a significantly lower risk of CHB (95%CI: 0.32-0.95, p=0.034 and 95%CI: 0.35-0.91, p=0.018) and HBV-related LC (95%CI: 0.24-0.89, p=0.022 and 95%CI: 0.28-0.90, p=0.021). A similar decreased risk was also found with the A-607C-137 haplotype. With respect to IL-18 expression, it was significantly lower in both patient groups, but no association was noted between the two polymorphisms in the IL-18 gene and its expression.

CONCLUSIONS

Our study indicated that the -137C allele in the IL-18 gene may be a protective factor for HBV-related disease, and serum IL-18 level may be inversely associated with CHB and HBV-related LC.

Association between Interleukin-18 Polymorphisms and Hepatocellular Carcinoma Occurrence and Clinical Progression

We investigated the association between interleukin-18 (IL-18) polymorphisms and the susceptibility and clinicopathological state of hepatocellular carcinoma (HCC). In total, 901 participants, including 559 healthy controls and 342 patients with HCC, were recruited. The allelic discrimination of -607A/C (rs1946518) and -137G/C (rs187238) polymorphisms of IL-18 was assessed through real-time polymerase chain reaction by performing the TaqMan assay. The IL-18 -137G/C polymorphism but not the -607A/C polymorphism showed a significant association with the risk of HCC. Participants carrying the IL-18 -137 polymorphism with heterozygous G/C and homozygous CC genotypes showed a 1.987-fold increase (95% CI = 1.301-3.032; p = 0.001) in the risk of HCC compared with those homozygous for wild-type G/G. The 342 patients with HCC carrying the IL-18 -137G/C polymorphism were positive for hepatitis B virus (HBV) infection with an adjusted odds ratio of 1.668. Moreover, the 142 HBV positive patients with HCC and the IL-18 -137 polymorphism were positive for at least one C genotype and showed significant vascular invasion (p = 0.018). Furthermore, the level of α-fetoprotein was high in the patients carrying the IL-18 -137 polymorphism with GC+CC alleles (p = 0.011). In conclusion, the IL-18 -137G/C polymorphism with a GC+CC genotype could be a factor that increases the risk of HCC. Furthermore, the correlation between the IL-18 -137G/C polymorphism and HCC-related HBV infection is a risk factor for vascular invasion and has a synergistic effect that can further enhance HCC prognosis.

Crosstalk between innate and adaptive immunity in hepatitis B virus infection

Hepatitis B virus (HBV) infection is a major public health problem worldwide. HBV is not directly cytotoxic to infected hepatocytes; the clinical outcome of infection results from complicated interactions between the virus and the host immune system. In acute HBV infection, initiation of a broad, vigorous immune response is responsible for viral clearance and self-limited inflammatory liver disease. Effective and coordinated innate and adaptive immune responses are critical for viral clearance and the development of long-lasting immunity. Chronic hepatitis B patients fail to mount efficient innate and adaptive immune responses to the virus. In particular, HBV-specific cytotoxic T cells, which are crucial for HBV clearance, are hyporesponsiveness to HBV infection. Accumulating experimental evidence obtained from the development of animal and cell line models has highlighted the importance of innate immunity in the early control of HBV spread. The virus has evolved immune escape strategies, with higher HBV loads and HBV protein concentrations associated with increasing impairment of immune function. Therefore, treatment of HBV infection requires inhibition of HBV replication and protein expression to restore the suppressed host immunity. Complicated interactions exist not only between innate and adaptive responses, but also among innate immune cells and different components of adaptive responses. Improved insight into these complex interactions are important in designing new therapeutic strategies for the treatment HBV infection. In this review, we summarize the current knowledge regarding the cross-talk between the innate and adaptive immune responses and among different immunocytes in HBV infection.