Interleukin-10 promoter polymorphism predicts initial response of chronic hepatitis B to interferon alfa

Changes in serum hepatitis B surface and e antigen, interferon-inducible protein 10, and aminotransferase levels during combination therapy of immune-tolerant chronic hepatitis B

BACKGROUND AND AIMS

Treatment of immune-tolerant (IT) children and adults with combined peginterferon alfa-2a and entecavir results in a decline in serum HBeAg and HBsAg concentrations but rarely results in loss of HBeAg or sustained off-treatment response. Factors associated with declines in these viral antigens during treatment remain unexplored.

APPROACH AND RESULTS

We investigated the pattern of virologic and biochemical response in 86 participants (59 children, 27 adults) by serial quantitative measurement of HBsAg (qHBsAg), quantitative HBeAg (qHBeAg), HBV RNA, interferon-inducible protein (IP-10), IL-18, and alanine aminotransferase (ALT). Each individual had previously been treated with 8 weeks of entecavir followed by 40 weeks of combined peginteferon and entecavir. We defined the interrelationships between these parameters and virologic response measured as nadir declines from baseline for HBeAg and HBsAg. The patterns of HBsAg and HBeAg decline were similar in pediatric and adult participants. Higher levels of IP-10 were observed during treatment in participants with greater ALT elevations and greater reductions of qHBsAg and qHBeAg. Individuals with peak ALT values exceeding three times the upper limit of normal were significantly more likely to have >1 log10 decline in both viral antigens. HBV DNA became undetectable in 21 of 86 (24%) and HBV RNA in 4 of 77 (5%) during therapy, but both markers remained negative only in those who became HBsAg negative, all of whom also had ALT elevations.

CONCLUSIONS

Induction of IP-10 during peginterferon treatment in adults and children in the IT phase of chronic HBV infection is associated with ALT elevations and decline in viral antigens, suggesting a degree of interferon-inducible viral control.

Suppression of Interferon-α Treatment Response by Host Negative Factors in Hepatitis B Virus Infection

Chronic hepatitis B virus (CHB) infection remains a major global public health issue for which there is still lacking effective curative treatment. Interferon-α (IFN-α) and its pegylated form have been approved as an anti-HBV drug with the advantage of antiviral activity and host immunity against HBV infection enhancement, however, IFN-α treatment failure in CHB patients is a challenging obstacle with 70% of CHB patients respond poorly to exogenous IFN-α treatment. The IFN-α treatment response is negatively regulated by both viral and host factors, and the role of viral factors has been extensively illustrated, while much less attention has been paid to host negative factors. Here, we summarized evidence of host negative regulators and parameters involved in IFN-α therapy failure, review the mechanisms responsible for these effects, and discuss the possible improvement of IFN-based therapy and the rationale of combining the inhibitors of negative regulators in achieving an HBV cure.

Association of TLR3 (rs3775291) and IL-10 (rs1800871) gene polymorphisms with susceptibility to Hepatitis B infection: A meta-analysis

TLR3 and IL-10 play a crucial role in antiviral defence. However, there is a controversy between TLR3 rs3775291 and IL-10 rs1800871 polymorphisms and the risk of hepatitis B virus (HBV) infection. The purpose of this study is to explore the relationship between the two single nucleotide mutations and the risk of HBV infection by meta-analysis. Medline, EMBASE, Web of Science, CNKI, China Wanfang database were searched for the case-control studies on the relationship between TLR3 rs3775291 and IL-10 rs1800871 polymorphism and susceptibility to HBV, updated to June 2020. The data were analysed by Stata 15.0 software. A total of 22 articles were included. The results showed that in the analysis of IL10 rs1800871 polymorphism and the risk of HBV infection, the pooled OR was 1.21 (95% CI 1.06-1.37), 1.28 (95% CI 1.04-1.56) and 1.20 (95% CI 1.06-1.37) and 1.40 (95% CI 1.07-1.83) in the allele model (C vs. T), dominant model (CC+CT vs. TT), recessive model (CC vs. CT+TT) and homozygous model (CC vs. TT), respectively. There was no statistical significance in the heterozygote model. A subgroup analysis of the Asian population showed similar results. The analysis of TLR3 rs3775291 polymorphism and the risk of HBV showed that in the allele model (T vs. C), the pooled OR was 1.30 (95% CI 1.05-1.61). Except for the recessive model, no significances were found in other genetic models. In conclusion, TLR3 rs3775291 and IL-10 rs1800871 polymorphisms are associated with the risk of HBV. Allele C and genotype CC at IL10 rs1800871 loci, as well as allele T and genotype TT at TLR rs3775291 loci, may increase susceptibility to Hepatitis B infection.

Interleukin-10 polymorphisms and susceptibility to ARV associated hepatotoxicity

Interleukin-10 (IL-10) is an anti-inflammatory cytokine associated with the inhibition of HIV replication. IL-10 polymorphisms were found to be linked to drug-induced hepatotoxicity. Hence we examined the prevalence of IL-10 (-819C/T,-1082A/G) polymorphisms in a total of 165 HIV patients which included 34 patients with hepatotoxicity, 131 without hepatotoxicity and 155 healthy controls by the PCR-RFLP method. In HIV patients with hepatotoxicity, the IL-10-819TT genotype increased the risk of ARV associated hepatotoxicity severity (OR = 1.61, P = 0.35). IL-10-819TT genotype was overrepresented in patients with hepatotoxicity as compared to healthy controls (26.5% vs. 13.5%, OR = 1.61, P = 0.46). IL-10 -819CT genotype was associated with advance HIV disease stage (OR = 0.49, P = 0.045). In HIV patients without hepatotoxicity, the IL-10-819TT genotype was more prevalent in patients consuming tobacco as compared to non-users (OR = 1.60, P = 0.41). In HIV patients without hepatotoxicity using both alcohol + efavirenz along with IL-10 -819CT genotype resulted in increased risk for the acquisition of ARV associated hepatotoxicity (OR = 4.00, P = 0.36). In multivariate logistic regression, taking nevirapine was associated with the risk hepatotoxicity severity (OR = 0.23, P = 0.005). In conclusion, an insignificant association between IL-10 polymorphisms and susceptibility to ARV associated hepatotoxicity.

Association of IL-10 polymorphisms with hepatitis B virus infection and outcome in Han population

BACKGROUND

This study evaluated the correlation of single nucleotide polymorphisms interleukin (IL)-10-592 and -1082 with hepatitis B virus (HBV) susceptibility and recovery.

METHODS

Total 190 chronic hepatitis B (CHB) patients, 81 individuals with self-limited HBV infections and 81 normal controls from the first Hospital of Jilin University were recruited. The IL-10 polymorphisms were detected by polymerase chain reaction with restriction fragment length polymorphism (PCR-RFLP). The χ (2) test (p < 0.05) and Fisher's exact test were separately performed to analyze and compare the genotype frequencies of IL-10-592 and -1082 among different groups. Furthermore, logistic regression analysis (p < 0.05) was conducted to determine the correlation of genotypes with HBV infection and recovery. Genotype A/A, A/C and C/C of IL-10-592 had been detected in the three groups.

RESULTS

The frequencies of -592A separately were 55.56, 64.67 and 55.33 % in the three groups. Genotypes of IL-10-592 only had significant difference among the patients and normal controls (p = 0.021). Genotypes A/A, A/G and G/G of IL-10-1082 were detected in CHB patients and individuals with self-limited HBV infection; however, genotype G/G had not been detected in normal controls. The frequencies of -1082G separately were 3.68, 6.17 and 11.11 % in the three groups. Genotypes of IL-10-1082 only had no significant difference among the patients and individuals with self-limited HBV infections (p = 0.130). We found that their risks of HBV infection existed significant difference.

CONCLUSION

The IL-10-592 and -1082 polymorphisms might be associated with HBV infection, but not with the recovery after HBV infection.

Association between interleukin-21 gene polymorphisms (rs12508721) and HBV-related hepatocellular carcinoma

Interleukin-21 (IL-21), as a multifunctional cytokine, plays an important role in many diseases, such as cancer, inflammatory and autoimmune diseases. We aimed to investigate the relationship between polymorphisms of IL-21 gene and susceptibility of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in a Chinese population. Studied subjects were divided into three groups: 100 patients with HBV-related HCC, 115 patients with chronic HBV infection and 127 healthy controls. Genomic DNA was isolated from peripheral blood, and the polymerase chain reaction-ligase detection reaction (PCR-LDR) method was used to genotype the SNPs (rs2221903, rs907715 and rs12508721) within IL-21 gene. Our results showed that IL-21 polymorphisms were associated with the risk of HCC and chronic HBV infection when compared with healthy controls. The rs2221903A/G AG genotype was associated with a higher risk of chronic HBV infection when compared with healthy controls [AG versus AA + GG, P = 0.036, OR = 1.898, 95%CI = 1.038-3.471]. The rs12508721C/T TT genotype was related with a lower risk of chronic HBV infection and HBV-related HCC than in healthy controls [TT versus CT + CC, P = 0.026, OR = 0.451, 95%CI = 0.221-0.920; P = 0.049, OR = 0.482, 95%CI = 0.231-1.005]. No significant difference in the genotype and allele distrubutions of rs907715G/A SNP was observed in the HBV-related HCC group, chronic HBV-infected group and the healthy control group when compared to each other. Our findings suggest that the rs12508721T/C and rs2221903A/G polymorphisms of IL-21 gene are associated with the susceptibility of HBV-related HCC and chronic HBV infection. The genetic variant may in fact cause protection against the HBV-related HCC. However, the function in these SNPs of IL-21 gene needs to clarify the mechanisms involved in the pathogenesis of HBV-related HCC further.

Association between the IFNA1 (-2Cx2192;T) Polymorphism and Increased IFNAR1 Gene Expression Levels in Chronic Hepatitis B Infection

BACKGROUND

Single nucleotide polymorphisms and variant expression of some interferon (IFN) genes in individuals with chronic hepatitis B virus (HBV) infection might be related to higher viral load and disease complications. Thereby, whole blood samples of 208 patients (94 chronic HBV-infected patients and 114 HBV immune subjects) were analyzed to investigate the association between IFNG (-5Ax2192;G), IFNA1 (-2Cx2192;T) and IFNAR1 (-97Tx2192;C) genes with their expression levels and HBV viral load.

METHODS

Genotyping was performed by high-resolution melting analysis with quantitative PCR (qPCR). Viral load quantification and gene expression were also carried out using qPCR.

RESULTS

Chronic HBV-infected subjects with IFNA1 CT genotype and T allele were more likely to develop protection against HBV when compared to immune subjects with wild-type genotype (IFNA1 CT/CC: OR = 0.45, p = 0.01, and T/C allele: OR = 0.55; p < 0.01). In patients with IFNAR1 wild-type TT genotype, the expression levels of this receptor may explain the lower viral load (r(2) = 0.40; p = 0.04) and protection against chronic infection.

CONCLUSIONS

These findings suggest that the polymorphic variant of IFNA1 (-2) gene is associated with chronic HBV infection, and high expression levels of the IFNAR1 gene and low levels of IFNA1 might contribute to the pathogenesis of chronic infection in these subjects.

Association Between IL-10 Gene Promoter Polymorphisms (-592 A/C, -819 T/C, -1082 A/G) and Susceptibility to HBV Infection in an Iranian Population

BACKGROUND

IL-10 can play a vital role in immune response against HBV. Three biallelic SNPs from the transcription start site control the transcription of the IL-10 gene. An association between susceptibility to HBV and IL-10 polymorphisms has been suggested in patients with HBV infection.

OBJECTIVES

The present study was designed to study the association between polymorphisms in interleukin-10 (-1082 A/G, -819 T/C and -592 A/C) promoter gene and chronic hepatitis B virus (HBV) infection.

PATIENTS AND METHODS

221 chronically infected patients and 200 healthy control subjects were enrolled in the study. Three biallelic (-1082 A/G, -819 T/C and -592 A/C) polymorphisms in the IL-10 promoter gene were determined by PCR-RFLP method.

RESULTS

Persistent HBV infection was associated with IL-10-1082 AG (P = 0.001) and GG (P = 0.004) genotypes and G (P = 0.000) allele. IL-10-819 T/C and -592 A/C genotype and allele frequencies did not show any correlation with the risk of chronic hepatitis B infection.

CONCLUSIONS

These results suggest that polymorphisms in interleukin-10 gene promoter influence clinical outcome of HBV infection and susceptibility to HBV infection.

Effects of interleukin 10 polymorphisms on the development of hepatitis B virus infection: a systemic review and meta-analysis

Current opinion varies in the roles of the IL-10 polymorphisms in the process of hepatitis B virus (HBV) infection. We have performed a systemic review and up-dated meta-analysis including 37 eligible case-control studies to summarize all the available data on the association between IL-10 polymorphisms and development of HBV infection. In the present study, we found that the IL-10-1082 G/A, -592 C/A polymorphisms were associated with a significantly decreased risk of chronic HBV infection (AA + GA vs. GG: P = 0.003, OR = 0.55, 95% CI = 0.37-0.82; AA vs. CA + CC: P = 0.03, OR = 0.83, 95% CI = 0.71-0.98). While the -819 C/T TT carriers were associated with a borderline significantly decreased risk of chronic HBV infection (TT vs. CT + CC: P = 0.05, OR = 0.82, 95% CI = 0.68-1.00). Significant result was observed in the association between IL-10-1082 G/A polymorphism and HBV clearance (AA vs. GG: P = 0.04, OR = 1.33, 95% CI = 1.01-1.75). In addition, significant association was found between the -1082 G/A, -819 C/T polymorphisms and an increased risk of progression of HBV infection from asymptomatic carrier to chronic hepatitis B (AA + GA vs. GG: P = 0.0003, OR = 2.13, 95% CI = 1.41-3.22; TT + CT vs. CC: P = 0.005, OR = 1.53, 95% CI = 1.13-2.07), whereas the -592 C/A polymorphism was associated with a significantly decreased risk of progression from asymptomatic carrier to hepatocellular carcinoma (AA vs. CC: P = 0.02, OR = 0.63, 95% CI = 0.43-0.92). Our meta-analysis suggested that the IL-10 polymorphisms might be associated with a decreased risk of chronic HBV infection, while the -1082 AA carriers might be more likely to clear HBV following acute infection. In addition, these three polymorphisms might cast in roles of the progression of HBV infection.

Interaction of TLR-IFN and HLA polymorphisms on susceptibility of chronic HBV infection in Southwest Han Chinese

BACKGROUND & AIMS

The toll-like receptor-interferon (TLR-IFN) signalling pathway plays a crucial role in HBV infection. Human leucocyte antigen (HLA) polymorphisms are associated with chronic HBV infection by genome wide association study (GWAS). We aimed to explore interaction between TLR-IFN and HLA gene polymorphisms in susceptibility of chronic HBV infection.

METHODS

In the Chinese Southwest Han population, 1191 chronic HBV infection patients and 273 HBV clearance were selected. A total of 39 single nucleotide polymorphism loci in 23 genes of the TLR-IFN pathway and four HLA polymorphism loci associated with chronic HBV infection identified by GWAS were selected for genotyping. SNPStats, QVALUE, and multifactor dimensionality reduction were used for statistical analysis.

RESULTS

A significant association was seen in several of the TLR-IFN pathway genes, TLR9 rs352140 (OR = 0.70, P = 0.0088), IL1B rs16944 (OR = 0.67, P = 0.016), IL12B rs3212227 (OR = 1.38, P = 0.021), IFNGR1 rs3799488 (OR = 1.48, P = 0.0048), IFNGR2 rs1059293 (OR = 0.27, P = 0.011), MX1 rs467960 (OR = 0.68, P = 0.022), as well as four loci in HLA, rs3077 (OR = 0.55, P < 0.0001), rs2856718 (OR = 0.60, P = 4e-04), rs9277535 (OR = 0.54, P < 0.0001) and rs7453920 (OR = 0.43, P < 0.0001). A synergistic relationship was seen between rs9277535 and rs16944 (0.13%), rs1143623 and rs6613 (0.10%). The combination of rs9277535 in HLA and rs16944 in IL1B was the best model to predict chronic HBV infection (testing accuracy = 0.6040, P = 0.0010, cross-validation consistency = 10/10).

CONCLUSIONS

TLR-IFN pathway gene polymorphisms are associated with chronic HBV infection. Interactions with polymorphisms in these genes may be one mechanism by which HLA polymorphisms influence susceptibility to chronic HBV infection, as specific single nucleotide polymorphism combinations are highly predictive of chronic HBV infection.

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 Interleukin-10 promoter polymorphisms with neurosyphilis

Interleukin 10 (IL-10) is a potent anti-inflammatory cytokine. Increased production of IL-10 has been found in late syphilis, presumably creating favorable conditions for bacteria persistence. Single-nucleotide polymorphisms (SNPs) within the promoter of IL-10 gene have been found to influence IL-10 production. We investigated whether SNPs in the IL-10 gene promoter are associated with cerebrospinal fluid (CSF) levels of IL-10 and neurosyphilis. Polymorphisms in the gene for IL-10 (G→A mutation at the position -1084 and C→A mutation at the position -592) were sought in 35 patients with syphilis and 24 healthy volunteers. CSF examination (i.e. routine laboratory tests and IL-10 levels) was performed in all syphilis patients. Neurosyphilis was defined as reactive CSF VDRL test or CSF white blood cells⩾5/μL and CSF protein concentration⩾45mg/dL. Overall, 31% of patients with syphilis had neurosyphilis. CSF IL-10 levels were significantly higher in patients with neurosyphilis when compared to those with syphilis but not neurosyphilis. -1082 GG and -592 CC genotypes were significantly associated with higher CSF IL-10 levels. Moreover, these genotypes were found to be more frequent in individuals with neurosyphilis in comparison to those without neurosyphilis. Anti-inflammatory immune response seems to be important in pathogenesis of neurosyphilis. Our data suggest that host-related factors, such as SNPs of immune regulatory genes may influence the susceptibility to neurosyphilis.

Association of IL28B polymorphisms with peginterferon treatment response in Chinese Han patients with HBeAg-positive chronic hepatitis B

AIMS

To investigate whether IL28B polymorphisms could affect the treatment response to peginterferon alpha (PEG-IFN) in chronic hepatitis B (CHB) patients in the Chinese Han population.

METHODS

A total of 212 hepatitis B e antigen (HBeAg)-positive patients treated with PEG-IFN monotherapy were enrolled in this study. Genotype analysis was performed for IL28B rs12980275, rs12979860 and rs8099917 using the MassArray system. Response was defined as cases showing normal aminotransferase (ALT) levels, HBV DNA level < 200 IU/ml and HBeAg seroconversion after 48 weeks of PEG-IFN therapy.

RESULTS

The patients were infected with hepatitis B virus (HBV) genotype B (44.8%) and C (55.2%) with a total response rate of 34.9%. For the three SNPs, there were significant differences between the response (R) and non-response (NR) groups both in allele frequencies and genotype distributions. IL28B genotype was independently associated with R for AA vs. N-AA (OR 2.70, 95% CL 1.21-6.01; P = 0.015) at rs12980275 after adjustment for sex, age, HBV genotype, baseline levels of HBV DNA and ALT. There were similar results for rs12979860 CC vs. N-CC (OR 2.56, 95% CL 1.15-5.67; P = 0.021) and rs8099917 TT vs. N-TT (OR 2.80, 95% CL 1.23-6.39; P = 0.015) respectively. Furthermore, one block formed by rs12980275 and rs12979860 was identified in this study. In multivariate analyses, the most common haplotype A-C was independently associated with high rates of R (OR 2.53, 95% CL 1.20-5.34; P = 0.015).

CONCLUSIONS

Our study suggested that genetic variations in IL28B may play a critical role in PEG-IFN efficacy in HBeAg-positive CHB patients in Han Chinese.

A -819 C/T polymorphism in the interleukin-10 promoter is associated with persistent HBV infection, but -1082 A/G and -592A/C polymorphisms are not: a meta-analysis

Single-nucleotide polymorphisms (SNPs) in the interleukin-10 (IL10) gene promoter have been associated with persistent hepatitis B virus (HBV) infection. In particular, the -1082A/G, -819 C/T and -592 A/C polymorphisms have most often been implicated. We performed a meta-analysis of available data to determine the relative importance of these SNPs in persistent HBV infection. We searched available articles in NCBI PubMed, EMBASE, the Chinese National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CBM) and identified 24 studies for inclusion in our meta-analysis. Our results indicated that the presence of the IL10 -819 C allele significantly increased the risk for persistent HBV infection (CC+CT vs. TT: OR = 1.283, 95 % CI 1.023-1.610, P = 0.031; C vs. T: OR = 1.183, 95 % CI 1.001-1.399, P = 0.049). Meanwhile, the -1082A/-819T/-592A haplotype (OR = 0.751, 95 % CI 0.640-0.881, P = 0.000) and the -1082A/-819C/-592C haplotype (OR = 1.568, 95 % CI 1.304-1.884, P = 0.000) were observed to be significantly associated with HBV disease progression in Asians. In contrast, the IL10 -1082A/G and -592A/C polymorphisms were not associated with an increased susceptibility to or outcome of HBV infection. Our meta-analysis supports the growing body of evidence that the presence of the IL10 -819 C/T polymorphism is associated with persistent HBV infection and that the -1082A/-819T/-592A haplotype and the -1082A/-819C/-592C haplotype are associated with HBV disease progression in Asians.

Lack of Association between Interleukin-10 Gene Promoter Polymorphisms with HIV Susceptibility and Progression to AIDS

BACKGROUND

Interleukin (IL)-10 is an important anti-inflammatory and immunomodulatory cytokine. Some authors believe that single nucleotide polymorphisms (SNP) in the promoter region of the IL-10 gene have been associated with susceptibility to HIV infection and progression to AIDS, but its role is not clearly defined yet. The present study was undertaken to evaluate the association between HIV infection susceptibility and progression with SNP in the promoter region of the IL-10 gene.

METHODS

This study was carried out in 70 HIV infected patients (39 treatment naïve and 31 under treatment) and 31 matched healthy controls. The biallelic polymorphisms in the IL-10 gene promoter (-592 ,-1082) were analyzed by polymerase chain reaction and direct sequencing.

RESULTS

At position -1082, G/A was the most common genotype and A was the most prevalent allele and at position -592, A/C was the most prevalent genotype and -592 C was the most common allele in HIV positive patients; although there was not any significant difference between cases and controls regarding genotypes and alleles of these regions.

CONCLUSION

Our study showed that genetic polymorphisms of IL-10 promoter region may not associate with HIV infection outcome and the lack of this association suggests that other genes may influence on HIV infection course.

Interleukin 18 gene promoter polymorphisms and susceptibility to chronic hepatitis B infection: a review study

CONTEXT

The variation in clinical outcome of hepatitis B virus (HBV) infection is determined by virological, immunological and host genetic factors. Genes encoding cytokines are one of the candidates among host genetic factors. Polymorphisms in gene promoter can lead to different levels of cytokine expression and unique immune response. Being involved in the inflammatory cytokine network, interleukin-18 (IL-18) plays an important role in pathogenesis of HBV infection. The aim of this review is considering available literature on the association between IL-18 gene promoter single nucleotide polymorphisms (-137 C/G and -607 A/C) and susceptibility to chronic HBV infection.

EVIDENCE ACQUISITION

Published literature from PubMed, EMBASE, and other databases were retrieved. All studies investigating the association of IL-18 gene promoter SNPs, -137 C/G and -607 A/C, with susceptibility to chronic HBV infection were included.

RESULTS

Findings showed that the genotype -607A/A is associated with the susceptibility to chronic hepatitis B. Furthermore, allele C at position -137 is suggested to play a protective role against development of chronic HBV infection.

CONCLUSIONS

Host genetic factors play an important role in determining the outcome of HBV infection. It is suggested that IL-18 genotype -607 A/A is associated with susceptibility to chronic hepatitis B. Furthermore, the carriage of allele C at position -137 may play a protective role in the development of chronic HBV infection.

Association between IL-10 gene promoter polymorphism and hepatitis B viral infection in an Egyptian population

Cytokines play critical roles in the pathogenesis of hepatitis B virus infection (HBV). This work was designed to study the effect of IL-10 gene polymorphisms (-1082G/A and -819C/T) on susceptibility of Egyptians to HBV. Genotyping was performed using single-stranded polymorphism-polymerase chain reaction in 118 Egyptian hepatitis B patients and 119 healthy controls, and IL-10 serum levels were measured using ELISA. The frequency of IL-10 -1082G/G was significantly higher in HBV patients than in healthy controls, and G/A and A/A were not significantly different between groups. The distribution of IL-10 -819 genotypes was not significantly different between the HBV and healthy control groups. Although AT was significantly different between controls and patients, the distribution of the other haplotypes was not. IL-10 levels were significantly lower among hepatitis B patients. Our data stress the importance of IL-10 gene polymorphism in HBV infection. Depending on our preliminary work, IL-10 -1082G/G may act as a host genetic factor in the susceptibility to HBV infection in Egyptians.

Long-term outcomes after nucleos(t)ide analogue discontinuation in HBeAg-positive chronic hepatitis B patients

Nucleos(t)ide analogue (NUC) resistance is an important clinical risk resulting from long-term therapy in chronic hepatitis B (CHB) management. Discontinuation of NUCs is a feasible strategy to reduce resistance. We aimed to observe the outcomes after NUC withdrawal in HBeAg-positive CHB patients. A total of 97 patients (11 patients with HBsAg loss and 86 patients with sustained HBeAg seroconversion) were enrolled. HBV DNA levels and alanine aminotransferase (ALT) levels were monitored regularly after discontinuation. Relapse was defined as HBV DNA levels >2000 IU/mL in at least two determinations more than 4 weeks apart. HBeAg seroconversion was achieved within 48 weeks (interquartile range (IQR), 24-72 weeks). The time on consolidation therapy was 96 weeks (IQR, 84-144 weeks). No relapses occurred for HBsAg loss patients. Evidence of relapse was observed in 9.3% of HBeAg seroconversion patients. All relapse cases occurred within 48 weeks after discontinuation. The time to relapse was 33 ± 15 weeks. Elevation of HBV DNA and ALT levels over baseline were only observed in 12.5% of relapse patients. There were no significant differences in baseline characteristics (sex, HBV genotype, age or ALT levels) or time on consolidation therapy between patients with relapse or sustained response. NUC discontinuation in HBeAg-positive CHB patients is feasible after achieving HBeAg seroconversion at a minimum of 24 weeks. There is further benefit to prolonging the time on consolidation therapy to reduce relapse. More than 48 weeks of sustained response is a predictive marker for long-term sustained response.

Association of interleukin-10 polymorphisms with chronic hepatitis C virus infection in a case-control study and its effect on the response to combined pegylated interferon/ribavirin therapy

We conducted a case-control study involving 150 genotype 3 chronic hepatitis C virus (HCV) patients and 150 healthy controls to investigate the association of polymorphisms in the interleukin-10 (IL-10) gene with chronic HCV infection and the association of these polymorphic variants with the combination of pegylated interferon (Peg-IFN) and ribavirin therapy response. Our data revealed that the GG genotype of IL-10 –1082A/G exhibited significant association with genotype 3 chronic HCV infection compared to controls. Treatment response data also showed a significant increase in risk for the GG genotype of IL-10 –1082A/G in response-relapse patients or non-responder patients compared to sustained virological response patients. Further, a significant increase in risk was also revealed for the CC genotype of IL-10 –592A/C in response-relapse patients or non-responder patients compared to sustained virological response patients, suggesting a role of the GG genotype of IL-10 –1082A/G and CC genotype of IL-10 –592A/C in the treatment outcome of combined Peg-IFN/ribavirin therapy.

An initial assessment of correlations between host- and virus-related factors affecting analogues antiviral therapy in HBV chronically infected patients

BACKGROUND

Success in treating hepatitis B virus (HBV) infection with nucleoside analogues drugs is limited by the emergence of drug-resistant viral strains upon prolonged therapy. In addition to mutation patterns in the viral polymerase gene, host factors are assumed to contribute to failure of treatment in chronic HBV infections. The aim of this study was to analyze the correlation between efficacy of antiviral therapy and the prevalence of HBV pretreatment drug-resistant variants. We also analyzed the role of heterogeneity in the promoter region of the IL-10 on the HBV pol/s gene polymorphisms and efficacy of analogues-driven therapy.

MATERIAL AND METHODS

HBV DNA was extracted from 54 serum samples from chronic hepatitis B (CHB) patients. Drug-resistance mutations were analyzed using MALDI-TOF mass spectrometry technology (MALDI-TOF MS) and Multi-temperature single-strand conformation polymorphism (MSSCP). IL-10 gene promoter region polymorphisms at positions -1082, -819, and -592 were determined in allele-specific PCR reactions (AS-PCR).

RESULTS

Drug-resistance mutations were detected in 74% of naïve and 93% of experienced patients, but the effect of pre-existence of drug-resistant HBV variants on antiviral therapy was not statistically significant (p=0.86). The role of polymorphisms at positions -1082 (p=0.88), -819 (p=0.26), and -592 (p=0.26) of IL-10 promoter region polymorphisms was excluded from the response-predicting factors. The main host factors predicting successful response to antiviral therapy were female sex (p=0.007) and young age (p=0.013).

CONCLUSIONS

The presence of drug-resistant HBV variants in baseline is not a viral predictor of good response to nucleoside/nucleotide analogues therapy. Only low HBV viral load predicted positive response to antiviral therapy. The ideal candidate for antiviral therapy is an immunocompetent, young female with low HBV viral load and elevated ALT activity.

Role of proinflammatory cytokines (interferon gamma) and anti-inflammatory cytokine (interleukin-10) gene polymorphisms in chronic hepatitis B infection: an Indian scenario

Immune-mediated mechanisms have been found to play an important role in the progression of hepatitis B virus (HBV) infection. The outcomes of infection do not appear to be determined by viral strains. Instead, allelic variants in human genome are likely to affect the disease progression. Allelic variation of proinflammatory cytokines such as interferon gamma (IFN-γ) participates in the elimination of HBV, and interleukin-10 (IL-10) helps in inhibition of Th1 effector mechanisms for host defense. The aim of this study was to determine the influence of host genetic factors in chronic HBV infection and gene promoter polymorphism or single-nucleotide polymorphism analysis of IFN-γ+874 and IL-10 (-1082, -592, and -819) on disease progression and persistence. A total of 232 patients along with 76 healthy controls were included. Allele-specific primers for IFN-γ and restriction fragment length polymorphism for IL-10 were used. The study indicated that low IFN-γ expression probably impairs host immune response to HBV, rendering these subjects more prone to HBV infection. No significant differences were detected between the 2 groups in the distributions of IL-10 genotype at the -1082, -819, and -592 positions. Odds ratio indicated that heterozygosity of genotypes -819 CT and -592 AC was more strongly associated with liver chronicity. Significantly, AA homozygous genotype was dominant in chronic hepatitis B cases in IFN-γ+874 and IL-10 (-1082 and -592) and is associated with increased risk of persistent infection.

Haplotypes of the IL10 gene as potential protection factors in leprosy patients

Leprosy is an infectious disease caused by Mycobacterium leprae characterized by dermatoneurological signs and symptoms that has a large number of new cases worldwide. Several studies have associated interleukin 10 with susceptibility/resistance to several diseases. We investigated haplotypes formed by three single nucleotide polymorphisms (SNPs) located in the IL10 gene (A-1082G, C-819T, and C-592A) in order to better understand the susceptibility to and severity of leprosy in an admixed northern Brazil population, taking into account estimates of interethnic admixture. We observed the genotypes ACC/ACC (P = 0.021, odds ratio [OR] [95% confidence interval (CI)] = 0.290 [0.085 to 0823]) and ACC/GCC (P = 0.003, OR [95% CI] = 0.220 [0.504 to 0.040]) presenting significant results for protection against leprosy development, framed in the profiles of low and medium interleukin production, respectively. Therefore, we suggest that genotypes A-1082G, C-819T, and C-592A formed by interleukin-10 polymorphisms are closely related to protection of the leprosy development in an admixed northern Brazil population, in particular ACC/ACC and ACC/GCC genotypes.

No correlation between interleukin-10 gene promoter polymorphisms and hepatitis B virus infection outcome

BACKGROUND

Single nucleotide polymorphisms (SNP) in the promoter region of the interleukin (IL)-10 genes have a role in determining hepatitis B virus (HBV) outcome.

OBJECTIVES

This study evaluates the correlation between HBV infection and SNP in IL-10 gene promoter.

PATIENTS AND METHODS

Ninety-six HBV-infected patients (32 chronic hepatitis B infection patients, 34 healthy carriers, 30 spontaneously recovered cases) and 31 healthy controls were enrolled. Three biallelic (-819,-592,-1082) regions in the IL-10 gene promoter were sequenced for all patients.

RESULTS

Genotypes and haplotypes of IL-10 gene promoter region at position -1082, -819 and -592 were not significantly different among controls, HBV recovered cases, carriers and chronic HBV patients. Nevertheless, A/A genotype at position -592 and T/T genotype at position -819 were more frequently seen in the HBV clearance group, while frequency of G/G genotype at position -1082 was more prevalent in the persistence group. GCC/GCC and GCC/ACC haplotypes were significantly observed in anti-HBe positive individuals.

CONCLUSIONS

Our findings showed that IL-10 promoter polymorphisms were not correlated with HBV infection prognosis. Nevertheless, individuals carrying high and intermediate producer of IL-10 haplotypes had a better ability to develop anti-HBe than low producer carriers.

Polymorphism of estrogen receptor alpha (ESR1) is associated with virological response to entecavir (ETV) in nucleoside-naïve adult patients with chronic hepatitis B

INTRODUCTION

Polymorphisms in estrogen receptor alpha (ESR1) are reported to be associated with the susceptibility to persistent HBV infection, HBV liver cirrhosis and HBV-related hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

To test the hypothesis that polymorphisms in estrogen receptor alpha (ESR1) might influence the virological response to entecavir (ETV) therapy, we examined two polymorphisms (PvuII and XbaI) in 76 nucleoside-naïve chronic hepatitis B (CHB) patients. All of the patients (52 HBeAg-positive and 24 HBeAg-negative) were treated with ETV 0.5 mg daily and followed up for a median time of 96 weeks (range 48-96). Polymorphisms were determined using the polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) method.

RESULTS

Under an additive model, the univariate analysis showed that patients carrying the PvuII T/C genotype might have higher virological responders than those carrying the T/T and C/C genotypes at week 48 (87.7 vs. 57.1 vs. 58.3 %; P = 0.012) and week 96 (96.7 vs. 64.3 vs. 24 87.5 %; P = 0.018), although this difference disappeared with the multiple analysis at week 48 [95 % confidence interval (CI) 0.687-3.841; P = 0.269] and week 96 (95 % CI 0.861-18.016; P = 0.077). Conversely, the univariate analysis suggests statistical significance between the recessive model of PvuII (TT vs. TC/CC) and virological response at week 48 (57.1 vs. 81.1 %; P = 0.033) and week 96 (64.3 vs. 94.7 %; P = 0.017). Multiple regression analysis affirmed the significant and independent association between the recessive model of PvuII and virological response. In other words, patients carrying at least one PvuII C allele (TC/CC) had a better likelihood of achieving virological response compared with those carrying the T/T genotype at week 48 (95 % CI 1.026-14.785, P = 0.046) and week 96 (95 % CI 1.456-57.509; P = 0.018). XbaI polymorphisms were not significantly associated with virological response.

CONCLUSION

Our results suggest that the PvuII polymorphism may play an important role in determining ETV efficacy after 48 and 96 weeks of treatment, at least in this study population.

Interleukin-10 (IL-10) polymorphisms are associated with IL-10 production and clinical malaria in young children

The role of interleukin-10 (IL-10) in malaria remains poorly characterized. The aims of this study were to investigate (i) whether genetic variants of the IL-10 gene influence IL-10 production and (ii) whether IL-10 production as well as the genotypes and haplotypes of the IL-10 gene in young children and their mothers are associated with the incidence of clinical malaria in young children. We genotyped three IL-10 single nucleotide polymorphisms in 240 children and their mothers from a longitudinal prospective cohort and assessed the IL-10 production by maternal peripheral blood mononuclear cells (PBMCs) and cord blood mononuclear cells (CBMCs). Clinical episodes of Plasmodium falciparum malaria in the children were documented until the second year of life. The polymorphism IL-10 A-1082G (GCC haplotype of three SNPs in IL-10) in children was associated with IL-10 production levels by CBMC cultured with P. falciparum-infected erythrocytes (P = 0.043), with the G allele linked to low IL-10 production capacity. The G allele in children was also significantly associated with a decreased risk for clinical malaria infection in their second year of life (P = 0.016). Furthermore, IL-10 levels measured in maternal PBMCs cultured with infected erythrocytes were associated with increased risk of malaria infection in young children (P < 0.001). In conclusion, IL-10 polymorphisms and IL-10 production capacity were associated with clinical malaria infections in young children. High IL-10 production capacity inherited from parents may diminish immunological protection against P. falciparum infection, thereby being a risk for increased malaria morbidity.