Impact of interleukin 28B polymorphisms on spontaneous clearance of hepatitis C virus infection: a meta-analysis

A case of a patient infected with a hepatitis C virus genotype 3a multidrug resistant variant in Pakistan

BACKGROUND

Approximately 10 million people in Pakistan are infected with the hepatitis C virus (HCV). Most patients develop chronic hepatitis, with rare cases of spontaneous clearance. However, little is known about multidrug resistant viral variants in Pakistan.

FINDINGS

This case study describes a 47-year-old male diagnosed with chronic HCV genotype 3a infection in 2003. After an initial diagnosis of viral infection, the patient remained treatment naïve for 5 years. He received two therapy cycles of interferon (IFN) plus ribavirin (RBV) in 2007 and 2010, however, he was non-responsive to the therapy. The patient then received an additional two treatment cycles of pegylated IFN α-2b plus RBV (in 2011 and 2013); he was still non-responsive. In 2016, the patient underwent sofosbuvir plus RBV combination therapy, however, the sustained virological response was still not achieved. The host genetic factor was found to be heterozygous guanine and thymine (GT) and cytosine and thymine (CT) genotypes of rs8099917 and rs12979860 polymorphism of IL28B, respectively. Phylogenetic analysis suggests that the resistant variant belong to an out-group and may require triple therapy.

CONCLUSIONS

This is the first case that reports on a HCV-infected individual who was a non-responder to multiple IFN therapies in Pakistan. Further studies are needed to understand multidrug-resistant HCV variants in the Pakistani population.

Interferon Lambda 4 Polymorphism Predicts Sustained Viral Response in Hepatitis C Virus Patients Irrespective of Hepatitis C Virus Genotypes, Ethnicity or Treatment Regimen: Results From a Meta-Analysis

CONTEXT

There is growing evidence that interferon lambda 4 (IFNL4) polymorphism is related to sustained virological response (SVR) in hepatitis C virus (HCV) infection. We analyzed the relationship between IFNL4 (rs368234815) polymorphism and SVR in dual- and triple- therapy in HCV genotype 1, 2, 3 and 4 infected Asian, Caucasian and African patients.

EVIDENCE ACQUISITION

We performed a systematic search of PubMed, Medline, Embase, EBSCO and Web of Science databases up to July 2015. Data of qualified studies were analyzed using the meta-analysis method in Stata 12.0 software.

RESULTS

Ten studies involving 4765 patients were included in the analysis. Of overall studies, SVR was more frequent in TT/TT genotype compared to TT /ΔG+ΔG /ΔG (OR = 4.439, 95% CI: 3.410 - 5.778). Genotype stratification analyses revealed rs368234815 TT/ TT was associated with higher SVR in G1, G2/3 and G4 HCV patients (ORG1 = 4.661, 95% CI: 3.937 - 5.518; ORG2/3 = 1.896, 95% CI: 1.265 - 2.841; ORG4 = 6.074; 95% CI: 3.129 - 11.788). Ethnicity stratification analyses of G1 patients showed that SVR was more frequent with TT/ TT genotype in Asians (OR= 8.245, 95% CI: 5.475 - 12.416), Caucasians (OR = 4.166, 95% CI: 3.441 - 5.042) and Africans (SVR: 37.5% vs 17.0%, P = 0.017). Moreover, similar results presented in therapy stratification analyses both in patients with dual-therapy (OR = 3.857; 95% CI: 3.288 - 4.524) or triple-therapy (OR = 8.119; 95% CI: 4.942 - 13.340).

CONCLUSIONS

Favorable IFNL4 rs368234815 genotype is a strong predictor of SVR in HCV patients, irrespective of HCV genotypes, ethnicity or treatment regimen. Thus, detection for IFNL4 rs368234815 polymorphism may be beneficial to guide the clinician in the individualization of therapy and design.

IL28B polymorphism (rs12979860) associated with clearance of HCV infection in Poland: systematic review of its prevalence in chronic hepatitis C patients and general population frequency

BACKGROUND

A common single nucleotide polymorphism (rs12979860) of the interleukin-28B (IL28B) gene is strongly associated with spontaneous and treatment-related eradication of HCV infection. In this study we estimated rs12979860 genotypes distribution among chronic hepatitis C patients in Poland using a systematic review of published studies and compared this data with the prevalence of rs12979860 variants of IL28B in representative sample of the Southern Poland population.

METHODS

Systematic review on rs12979860 variant prevalence in the Polish chronic HCV subjects was performed. Additionally, age- and gender-stratified population sample was recruited from inhabitants of Kraków using a randomized municipal census data, DNA samples available for 538 individuals were genotyped using a real-time PCR method.

RESULTS

The frequency of homozygotes TT was from 15 to 27% and carriers of unfavorable T alleles (genotypes CT and TT) were present in 70-80% of chronic HCV subjects. In the general population, 47% individuals were CC homozygous, 42% CT heterozygous and 11% TT homozygous. The population frequency of T allele was 0.318 (95% CI: 0.291-0.347) and the variant was in Hardy-Weinberg equilibrium. Distributions of IL28B genotypes in chronic HCV patients were characterized by a departure from the genetic equilibrium and differed significantly from the random population sample.

CONCLUSIONS

Events of spontaneous viral clearance can fully explain differences between genotype distributions in general population and chronic HCV subjects and a departure from the genetic equilibrium. This is the first study estimating the prevalence of IL28B rs12979860 SNP in the Southern Poland population based on a random representative sample.

Association analysis of polymorphisms in OAS1 with susceptibility and severity of hand, foot and mouth disease

Hand, foot and mouth disease (HFMD) is a common childhood illness that mainly affects Asian children under the age of 5 years. Human enterovirus 71 (EV71) and coxsackievirus A16 (CA16) are the most common pathogens of HFMD. It is imperative that the susceptible population is screened early and that the severe illness population can be identified via genetic variation detection in children. Four single-nucleotide polymorphisms (SNP) [2'-5'-oligoadenylate synthetase1 (OAS1) rs10774671, selectin P ligand (SELPLG) rs2228315, scavenger receptor class B member 2 (SCARB2) rs41284767 and interleukin 28B (IL28B) rs12979860] were determined by Taqman assays in 333 HFMD samples and 163 control samples. The rs2228315, rs41284767 and rs12979860 polymorphisms did not differ significantly between HFMD patients and the controls, but the prevalence of the rs10774671 polymorphism was significantly different between the control children and children infected with CA16 (GG genotype vs. AA + AG genotype, P < 0.05). Children with the GG genotype were more susceptible to CA16-type HFMD. Furthermore, the rs10774671 genotype distribution was clearly different between children with severe HFMD and those with mild HFMD [P < 0.05, OR 0.240, 95% CI (0.071-0.809)]. HFMD children with the AA+AG genotype were more likely to progress to encephalitis than were those with the GG genotype. Plasma γ-interferon (IFN) expression levels among control children and the mild and severe HFMD children were detected by ELISA. Those with mild HFMD had higher γ-IFN expression levels compared with those with severe HFMD (P < 0.05). In addition, there is a significant correlation between γ-IFN levels and OAS1 rs10774671 SNP, as analysed by linear correlation assay. The GG genotype correlated with higher γ-IFN levels (P < 0.05). In short, the OAS1 rs10774671 SNP GG genotype contributed to CA16 susceptibility and was associated with the development of mild HFMD.

Interleukin 28B polymorphism predicts interferon plus ribavirin treatment outcome in patients with hepatitis C virus-related liver cirrhosis: A multicenter retrospective study in Japan

AIM

This study evaluated the efficacy of interferon plus ribavirin and examined whether interleukin 28B (IL28B) polymorphism influenced treatment outcome in Japanese patients with hepatitis C virus (HCV)-related liver cirrhosis (LC).

METHODS

Fourteen collaborating centers provided details of 261 patients with HCV-related LC undergoing treatment with interferon plus ribavirin. Univariate and multivariate analyses were used to establish which factors predicted treatment outcome.

RESULTS

Eighty-four patients (32.2%) achieved a sustained virological response (SVR). SVR rates were 21.6% (41/190) in patients with HCV genotype 1 with high viral load (G1H) and 60.6% (43/71) in patients with non-G1H. In patients with non-G1H, treatment outcome was effective irrespective of IL28B polymorphism. In those with G1H, SVR was achieved in 27.1% of patients with the IL28B rs8099917 TT allele compared with 8.8% of those with the TG/GG alleles (P = 0.004). In patients with G1H having TT allele, treatments longer than 48 weeks achieved significantly higher SVR rates than treatments less than 48 weeks (34.6% vs 16.4%, P = 0.042). In patients with G1H having TG/GG alleles, treatments longer than 72 weeks achieved significantly higher SVR rates than treatments less than 72 weeks (37.5% vs 4.1%, P = 0.010).

CONCLUSION

Interferon plus ribavirin treatment in Japanese patients with non-G1H HCV-related LC was more effective than those with G1H and not influenced by IL28B polymorphism. In those with G1H, IL28B polymorphism may predict SVR and guide treatment duration: SVR rates were higher in those with the TT allele treated for more than 48 weeks and those with the TG/GG alleles treated for more than 72 weeks.