IL28B CC genotype is associated with higher all-cause mortality in antiretroviral-treated HIV-infected patients

AIDS incidence and survival in a hospital-based cohort of HIV-positive patients from São Paulo, Brazil: The role of IFN-λ4 polymorphisms

Few studies have reported the prognosis of human immunodeficiency virus (HIV)-positive patients followed for a long time in Brazil, particularly those including pre and post-HAART eras. The polymorphisms of interferon (IFN)-λ4 have been postulated as possibly associated with the pathogenesis of HIV infection. The aim of this study was to describe the incidence and mortality from a cohort of HIV-positive patients as well as whether IFN-λ4 gene polymorphisms (SNP rs8099917 and SNP rs12979860) were associated with HIV/acquired immune deficiency syndrome (AIDS) progression. We followed 402 patients for up to 30 years; 347 of them began follow-up asymptomatic, without any AIDS-defining opportunistic disease and/or a lymphocytes T CD4+ count of 350 cells/mm3 or lower. We determined the probability of the asymptomatic subjects to remain AIDS-free, and the risk of death for those entering the study already with an AIDS diagnosis, as well as for subjects developing AIDS during follow-up. We compared the prognosis of patients with two different polymorphisms for the genes encoding for IFN-λ4, variants rs8099917 and rs12979860. The follow-up time of the 347 asymptomatic-at-entry subjects was 3687 person-years. IFN-λ4 rs8099917 polymorphisms were not associated with AIDS progression, but IFN-λ4 rs12979860 wild type genotype (CC) was associated with higher mortality compared to CT and TT, with an increased probability of death from AIDS (P = .01). In conclusion, genetic variations in IFN-λ4 on rs12979860 polymorphisms in HIV-infected patients may drive mortality risk.

Interferon Lambda and Liver Fibrosis

Fibrosis is a highly conserved and coordinated wound healing response to injury. In the liver, injury is promoted by immune effector mechanisms that are common across various disease etiologies and even between organs such as lungs, kidneys, heart, and other organs. Thus, the liver represents a useful model to study inflammation and repair, particularly as it is frequently biopsied in clinical contexts. Currently, strong evidence implicates IFNL3/4 polymorphisms and interferon (IFN)-λ3 levels as determinants of the extent of hepatic inflammation and fibrosis in viral and nonviral liver diseases, as well as in governing the severity of nonhepatotropic viral diseases. Interestingly, IFNL3/4 polymorphisms and IFN-λ3 levels correlate with fibrosis extent in other organs such as the lung and kidney. In this review, we discuss the association between IFN-λ and tissue inflammation and fibrosis in human disease and the potential clinical utility of the findings.

IFNΛ3/4 locus polymorphisms and IFNΛ3 circulating levels are associated with COPD severity and outcomes

BACKGROUND

Interferon lambdas (IFNLs) have important anti-viral/bacterial and immunomodulatory functions in the respiratory tract. How do IFNLs impact COPD and its exacerbations?

METHODS

Five hundred twenty eight patients were recruited in a prospective observational multicentre cohort (PROMISE) study. The genetic polymorphisms (rs8099917 and rs12979860) within the IFNL3/4 gene region and circulating levels of IFNL3 in COPD patients were determined and associated with disease activity and outcome during a median follow-up of 24 months.

RESULTS

The GG genotype significantly influenced severe exacerbation rate (42 vs. 23%; p = 0.032) and time to severe exacerbation (HR = 2.260; p = 0.012). Compared to the TT or TG genotypes, the GG genotype was associated with severe dyspnoea (modified medical research council score ≥ median 3; 22 vs 42%, p = 0.030). The CC genotype of the rs12979860 SNP was associated with a poorer prognosis (body mass index, airflow obstruction, dyspnea and exercise capacity index ≥ median 4; 46 vs. 36% TC vs. 20.5% TT; p = 0.031). Patients with stable COPD and at exacerbation had significantly lower circulating IFNL3 compared to healthy controls (p < 0.001 and p < 0.001, respectively). Circulating IFNL3 correlated to post-bronchodilator FEV1%predicted and the tissue maturation biomarker Pro-collagen 3.

CONCLUSION

IFNL3/4 polymorphisms and circulating IFNL3 may be associated with disease activity and outcomes in COPD.

TRIAL REGISTRATION

Clinical Trial registration http://www.isrctn.com/ identifier ISRCTN99586989 on 16 April 2008.

Type I interferon and HIV: Subtle balance between antiviral activity, immunopathogenesis and the microbiome

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Induction and action of IFN during acute and chronic HIV-1 infection.

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Host and viral factors influencing IFN response in HIV-1 infected patients.

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Type I IFN and IFNα subtypes signatures and their antiviral activity during HIV-1 infection.

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The microbiome and intestinal IFN responses relationship in HIV-1 infection and disease.

Type I interferon (IFN) response initially limits HIV-1 spread and may delay disease progression by stimulating several immune system components. Nonetheless, persistent exposure to type I IFN in the chronic phase of HIV-1 infection is associated with desensitization and/or detrimental immune activation, thereby hindering immune recovery and fostering viral persistence. This review provides a basis for understanding the complexity and function of IFN pleiotropic activity in HIV-1 infection. In particular, the dichotomous role of the IFN response in HIV-1 immunopathogenesis will be discussed, highlighting recent advances in the dynamic modulation of IFN production in acute versus chronic infection, expression signatures of IFN subtypes, and viral and host factors affecting the magnitude of IFN response during HIV-1 infection. Lastly, the review gives a forward-looking perspective on the interplay between microbiome compositions and IFN response.

IFN-stimulated gene expression is independent of the IFNL4 genotype in chronic HIV-1 infection

This study aimed to evaluate the association between the IFNL4 rs368234815 (ΔG/TT) dinucleotide polymorphism and the IFN response during chronic HIV-1 infection. We carried out genotyping analysis and measured the expression of IFN-stimulated genes (ISGs) (myxovirus resistance protein A [MxA], ISG15, ISG56, apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like [APOBEC] 3F and APOBEC3G) on peripheral blood mononuclear cells collected from naïve and HAART-treated HIV-1-infected patients. There were no statistically significant differences in endogenous ISGs mRNA levels among HIV-1-positive patients bearing different IFNL4 genotypes, suggesting that ISG expression is independent of the IFNL4 genotype in HIV-1 infection.

Human leukocyte antigen B*57 does not fully explain hepatitis C clearance in HIV controllers

OBJECTIVE

HIV controllers demonstrate high rates of spontaneous clearance of hepatitis C virus (HCV) infection. The objective of this study was to evaluate the role of human leukocyte antigen (HLA) B*57 and other genetic polymorphisms on HCV clearance in HIV controllers.

DESIGN

This is a prospective cohort study.

METHODS

Patients in the Study of the Consequences of Protease Inhibitor Era (SCOPE) were tested for anti-HCV using enzyme immunoassay (EIA3) and HCV RNA using discriminatory HCV transcription-mediated amplification assay (Norvatis). We compared the proportion of HIV controllers and noncontrollers demonstrating HCV clearance and fitted multivariable Poisson regression models with robust standard errors to estimate adjusted prevalence ratios (APRs) and assessed genetic and immunologic predictors of HCV clearance.

RESULTS

Of 279 HIV/HCV seropositive individuals, 48 were HIV controllers. HIV controllers compared to HIV noncontrollers, were significantly more likely to have HLA B*57 (33 vs. 10%, P < 0.01). In multivariate analyses, adjusting for HLAB57, IL28B genotype, age, sex and race/ethnicity, HCV clearance was significantly more likely in HIV controllers than HIV noncontrollers [APR 1.78; 95% confidence interval (CI) 1.06-3.0; P = 0.03]. HLA B*57 did not explain the increased proportion of HCV clearance in HIV controllers, but IL28B CC genotype was independently associated with spontaneous HCV clearance (APR 2.76; 95% CI 1.85-4.11; P < 0.001).

CONCLUSION

Although enriched in HIV controllers, HLA B*57 does not explain the increased HCV clearance. Further identification of host immunologic or genetic factors that contribute to control of HIV and HCV may support the development of novel treatments for and effective vaccines against both viruses.

Immunity and hepatitis C: a review

Hepatitis C virus (HCV) is a major cause of chronic hepatitis and hepatocellular carcinoma worldwide. Due to shared transmission routes, the prevalence of HCV is especially high among individuals infected with HIV. HIV uninfected individuals spontaneously clear HCV approximately 30 % of the time, while the rate of control in HIV infected individuals who subsequently acquire HCV is substantially lower. In addition, complications of HCV are more frequent in those with HIV infection, making liver disease the leading cause of non-AIDS-related death in HIV infected individuals. This review summarizes recent advances in understanding the role of the innate and adaptive immune responses to HCV in those with and without HIV. Further defining the interaction between hepatitis C and the host immune system will potentially reveal insights into HCV pathogenesis and the host's ability to prevent persistent infection, as well as direct the development of vaccines.

Pharmacogenomics of hepatitis C infections: personalizing therapy

It is a widely held view that drug response genes have not proved as useful in clinical practice as anticipated at the start of the genomic era. An exception is in the treatment for chronic hepatitis C virus (HCV) genotype 1 infection with pegylated interferon α and ribavirin. In 2009, four independent genome-wide analyses identified IL28B polymorphisms that predict drug response in chronic hepatitis C (CHC). This discovery had immediate clinical impact. First, the IL28B genotype could be used to personalize therapy. In the 2 years since discovery, most of the more than 100,000 CHC patients commencing therapy for CHC in the West will have considered IL28B genotype testing. Second, the discovery has supported clinical trials for the use of the protein encoded by the gene known as interferon lambda. Third, it is expected that new insights into HCV pathogenesis will follow from studies of how IL28B affects HCV viral clearance and, ultimately, this will lead to new therapeutic strategies for CHC. This review discusses how IL28B genotyping is now used in personalizing therapy and, with the dramatically changing clinical landscape in CHC, with the advent of direct-acting antivirals, the prospects ahead.

Interferon-λs: special immunomodulatory agents and potential therapeutic targets

Interferon (IFN)-λs are a new addition to the old IFN family and share many similarities, such as antiviral and antiproliferative characteristics, with type I IFNs. IFN-λs also exhibit unique characteristics in immunomodulation. Accumulating studies have indicated the interactions between IFN-λs and immune cells, which lead to the regulation of the latter. IFN-λs can influence dendritic cells (DCs) and their product, IFN-λs-DCs, can then regulate the function of T cells. On the other hand, IFN-λs can also directly affect T cells through inhibition of the T helper 2 cell (Th2) responses. IFN-λs have varying immunomodulatory functions under different physiological conditions or in different organs and can inhibit tumor growth via regulation of the immune system. Diseases associated with IFN-λs include asthma, allergy, and systemic lupus erythematosus. In this review, we summarize the current knowledge of the biology of IFN-λs and their immunomodulatory function in relevant human diseases.

The impact of interferon lambda 3 gene polymorphism on natural course and treatment of hepatitis C

Host genetic factors may predict the outcome and treatment response in hepatitis C virus (HCV) infection. Very recently, three landmark genome-wide association studies identified single nucleotide polymorphisms near the interleukin 28B (IL28B) region which were more frequent in responders to treatment. IL28B encodes interferon (IFN)λ3, a type III IFN involved in host antiviral immunity. Favourable variants of the two most widely studied IL28B polymorphisms, rs12979860 and rs8099917, are strong pretreatment predictors of early viral clearance and sustained viral response in patients with genotype 1 HCV infection. Further investigations have implicated IL28B in the development of chronic HCV infection versus spontaneous resolution of acute infection and suggest that IL28B may be a key factor involved in host immunity against HCV. This paper presents an overview about the biological activity and clinical applications of IL28B, summarizing the available data on its impact on HCV infection. Moreover, the potential usefulness of IFNλ in the treatment and natural history of this disease is also discussed.