Clearance Of Hepatitis C Virus Infection Research Articles

Male Sexual Dysfunction Among Egyptian Patients with Chronic Hepatitis C Virus Infection Before and After Direct-Acting Antiviral Drugs

BackgroundChronic hepatitis C virus (HCV) infection is a global health burden that affects quality of life, with a negative impact on sexual functioning (SF). AimTo study male sexual dysfunction (MSD) among Egyptian men with chronic HCV infection and the impact of therapy with direct-acting antiviral drugs (DAAs) on their sexual health. MethodsThe self-administered International Index of Erectile Function (IIEF) questionnaire was completed by 400 sexually active male patients with chronic HCV infection without liver cirrhosis before the initiation of therapy with DAAs and then again at the completion of therapy. We compared these baseline questionnaires with those completed by a similar number of age-matched and socioeconomic status–matched controls. In the patients with HCV infection, we also compared IIEF questionnaires completed before and after DAA therapy. Main Outcome MeasureWe determined the proportions of patients and controls who were dissatisfied with their sexual life and the impact of clearing HCV infection on MSD and evaluated the impact of DAA therapy on the total IIEF score and scores in all IIEF domains. ResultsMen with chronic HCV infection before DAA treatment had significantly higher erectile dysfunction (ED) scores compared with controls, and scores increased with age (P < .0001). The average scores in all IIEF domains was significantly lower in the patients compared with controls in all age groups. Men with chronic HCV infection had significantly higher ED scores before cure than after cure (P < .0001). Clinical ImplicationsGiven the high prevalence of MSD in patients with chronic HCV infection, and given that curing the HCV virus can improve the MSD associated with HCV infection, it is recommended that sexual quality of life in men with HCV be addressed as part of the evaluation protocol before initiation of DAA treatment and again after cure in an effort to improve this particular aspect of quality of life. Strengths & LimitationsThis is the first study to report on MSD in the era of DAA therapy in Egyptian men with chronic HCV infection before the development of cirrhosis, with a relatively large study population. The use of a detailed version of the IIEF questionnaire reinforces the validity of our study. ConclusionChronic HCV infection negatively impacts MSD, affecting all domains of the IIEF, and effects increase with age. The MSD associated with HCV infection is significantly improved in patients who are cleared of the virus. These findings require further confirmation and need to be addressed as part of a comprehensive therapeutic plan to improve patients’ quality of life.Elshimi E, Morad W, Mohamad NE. Male Sexual Dysfunction Among Egyptian Patients with Chronic Hepatitis C Virus Infection Before and After Direct-Acting Antiviral Drugs. J Sex Rev 2019;16:402–409.

Abstract B109: Broadly neutralizing antibodies against HCV use a CDRH3 disulfide motif to recognize an E2 glycoprotein site that can be targeted for vaccine design

Abstract Hepatocellular carcinoma is the most common type of liver cancer and is responsible for approximately one million deaths each year. In the United States, persistent infection with hepatitis C virus (HCV) is among the leading causes of hepatocellular carcinoma. HCV vaccine efforts are hampered by genetic diversity of HCV envelope glycoproteins E1 and E2. Structural studies of broadly neutralizing antibodies (bNAbs) (e.g., HEPC3 and HEPC74) isolated from individuals who spontaneously cleared HCV infection will facilitate immunogen design to elicit antibodies against multiple HCV variants. However, challenges in expressing HCV glycoproteins previously limited bNAb-HCV structures to complexes with truncated E2 cores.New expression and purification techniques allowed us to produce bNAb complexes with full-length E2 ectodomains for structural studies. We solved crystal structures of HEPC3 and HEPC74 alone and complexed with E2 ectodomains. We measured the binding and neutralization potency of HEPC3/HEPC74-like germline precursors. Despite derivation from different individuals, HEPC3 and HEPC74 use the same germline heavy chain gene segments and possess a limited number of somatic mutations. We describe a shared CDRH3 disulfide motif that exhibits common interactions with a conserved epitope in the front layer of E2. The germline-encoded CDRH3 motif plays a critical role in initial recognition of HCV by naïve B cells. The structures of E2 ectodomain reveal regions (including a target of immunogen design) that were truncated or disordered in E2 core. We also identify candidate immunogens: E2 variants that bind to HEPC3/HEPC74-like germline precursors. These data reveal unusual structural features relevant to the fundamental understanding of antibody-antigen interactions. The identification of common genetic signatures of HCV bNAbs will facilitate lineage-targeted immunogen design to raise bNAbs against the conserved epitope in the E2 front layer. Citation Format: Andrew I. Flyak, Stormy Ruiz, Michelle Colbert, Tiffany Luong, James E. Crowe, Jr., Justin R. Bailey, Pamela J. Bjorkman. Broadly neutralizing antibodies against HCV use a CDRH3 disulfide motif to recognize an E2 glycoprotein site that can be targeted for vaccine design [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr B109.

Multi-Ancestry Genome-Wide Association Study of Spontaneous Clearance of Hepatitis C Virus

Spontaneous clearance of hepatitis C virus (HCV) occurs in approximately 30% of infected persons and less often in populations of African ancestry. Variants in major histocompatibility complex (MHC) and in interferon lambda genes are associated with spontaneous HCV clearance, but there have been few studies of these variants in persons of African ancestry. We performed a dense multi-ancestry genome-wide association study of spontaneous clearance of HCV, focusing on individuals of African ancestry. We performed genotype analyses of 4423 people from 3 ancestry groups: 2201 persons of African ancestry (445 with HCV clearance and 1756 with HCV persistence), 1739 persons of European ancestry (701 with HCV clearance and 1036 with HCV persistence), and 486 multi-ancestry Hispanic persons (173 with HCV clearance and 313 with HCV persistence). Samples were genotyped using Illumina (San Diego, CA) arrays and statistically imputed to the 1000 Genomes Project. For each ancestry group, the association of single-nucleotide polymorphisms with HCV clearance was tested by log-additive analysis, and then a meta-analysis was performed. In the meta-analysis, significant associations with HCV clearance were confirmed at the interferon lambda gene locus IFNL4-IFNL3 (19q13.2) (P= 5.99× 10-50) and the MHC locus 6p21.32 (P= 1.15× 10-21). We also associated HCV clearance with polymorphisms in the G-protein-coupled receptor 158 gene (GPR158) at 10p12.1 (P= 1.80× 10-07). These 3 loci had independent, additive effects of HCV clearance, and account for 6.8% and 5.9% of the variance of HCV clearance in persons of European and African ancestry, respectively. Persons of African or European ancestry carrying all 6 variants were 24-fold and 11-fold, respectively, more likely to clear HCV infection compared with individuals carrying none or 1 of the clearance-associated variants. In a meta-analysis of data from 3 studies, we found variants in MHC genes, IFNL4-IFNL3, and GPR158 to increase odds of HCV clearance in patients of European and African ancestry. These findings could increase our understanding of immune response to and clearance of HCV infection.

Hierarchical assessment of host factors influencing the spontaneous resolution of hepatitis C infection.

Hepatitis C virus (HCV) infection is associated with chronic liver disease, resulting in cirrhosis and hepatocellular carcinoma. Approximately 20% of HCV infections are spontaneously resolved. Here, we assessed the hierarchical relevance of host factors contributing to viral clearance. DNA samples from 40 resolved infections and 40 chronic HCV patients paired by age were analyzed. Bivariate analysis was performed to rank the importance of each contributing factor in spontaneous HCV clearance. Interestingly, 63.6% of patients with resolved infections exhibited the protective genotype CC for SNP rs12979860. Additionally, 59.3% of patients with resolved infections displayed the protective genotype TT/TT for SNP ss469415590. Moreover, a ranking of clearance factors was estimated. In order of importance, the IL28B CC genotype (OR 0.197, 95% CI 0.072-0.541) followed by the INFL4 TT/TT genotype (OR 0.237, 95% CI 0.083-0.679), and female gender (OR 0.394, 95% CI 0.159-0.977) were the main predictors for clearance of HCV infection. HCV clearance is multifactorial and the contributing factors display a hierarchical order. Identifying all elements playing role in HCV clearance is of the most importance for HCV-related disease management. Dissecting the relevance of each contributing factor will certainly improve our understanding of the pathogenesis of HCV infection.

HCV Broadly Neutralizing Antibodies Use a CDRH3 Disulfide Motif to Recognize an E2 Glycoprotein Site that Can Be Targeted for Vaccine Design

Hepatitis C virus (HCV) vaccine efforts are hamperedby the extensive genetic diversity of HCVenvelopeglycoproteins E1 and E2. Structures ofbroadlyneutralizing antibodies (bNAbs) (e.g., HEPC3, HEPC74) isolated from individuals who spontaneously cleared HCV infection facilitate immunogen design to elicit antibodies against multiple HCV variants. However, challenges in expressing HCV glycoproteins previously limited bNAb-HCV structures to complexes with truncated E2 cores. Here we describe crystal structures of full-length E2 ectodomain complexes with HEPC3 and HEPC74, revealing lock-and-key antibody-antigen interactions, E2 regions (including a target of immunogen design) that were truncated or disordered in E2 cores, and an antibody CDRH3 disulfide motif that exhibits common interactions with a conserved epitope despite different bNAb-E2 binding orientations. The structures display unusual features relevant to common genetic signatures of HCV bNAbs and demonstrate extraordinary plasticity in antibody-antigen interactions. In addition, E2 variants that bind HEPC3/HEPC74-like germline precursors may represent candidate vaccine immunogens.

Correlation of IL28Brs12979860 genotype and gender with spontaneous clearance of HCV infection: a Pakistani cross-section study.

There is a strong correlation of IL28B rs12979860 genetic variations and gender with spontaneous clearance of hepatitis C virus (HCV) infection. HCV-infected subjects were categorized into HCV spontaneous clearance (SC) group and chronic hepatitis C (CHC) group on the basis of anti-HCV antibodies and HCV RNA level and follow-up of 6 months. 35 subjects were classified in SC group and 165 subjects were classified in CHC group. IL28B rs12979860 genotypes were determined by allele-specific PCR. Multinominal logistic regression analyses revealed that both genders favor IL28B rs12979860 CT genotype (OR: 4.80; CI: 2.22-10.35; p =0.0005) and (OR: 3.47; CI: 1.63-7.43; p =0.001) for male and female, respectively, are significant in spontaneous clearance of HCV infection.

Incidence and spontaneous clearance of hepatitis C virus (HCV) in people who inject drugs at the Stockholm Needle Exchange-Importance for HCV elimination.

The major transmission route for hepatitis C virus (HCV) is through sharing of unsterile injection equipment among people who inject drugs (PWID). The WHO strategy for HCV elimination by 2030 proposes increased efforts to treat PWID populations that drive the HCV epidemic. Among participants in the Stockholm needle exchange programme (NEP), the HCV prevalence is 60%. We aimed to study HCV incidence, spontaneous HCV clearance rate, and predictors associated with new HCV infections and reinfections in NEP participants. All 2320 patients enrolled in the programme between 8 April 2013 and 23 September 2016 were tested for HCV at baseline, and responded to a questionnaire regarding sociodemographic data and injection risk behaviour. Tests for HCV were repeated at an interval of 3-6months. The anti-HCV prevalence in the NEP participants at baseline was 77%, and the prevalence of HCV RNA was 57%. 24% of the anti-HCV positive were HCV RNA negative with a spontaneously cleared HCV infection. The overall HCV incidence rate was 22/100 PY. The HCV incidence rate in the HCV naive group was 26/100 PY, and in the spontaneously cleared group 19/100. Although there were no significant differences in becoming HCV infected between the two groups (31% vs 29%), the rate of spontaneous HCV clearance was significantly lower in the HCV naive group, 20% vs 44%, (P<0.05). A high HCV incidence rate was noted among the PWID indicating that treatment needs to be scaled up in conjunction with harm reduction measures to achieve HCV elimination goals set by WHO. This includes high coverage needle exchange programmes and effective addiction treatment for substance users, including opiate substitution treatment.

Spontaneous Viral Clearance in Sixteen HIV-Infected Patients with Chronic Hepatitis C

Background/Aims: Spontaneous viral clearance of the chronic hepatitis C virus (HCV) in human immunodeficiency virus (HIV)-infected patients is a rare event. We aimed to identify the clinical, therapeutic, demographic, and laboratory features associated with spontaneous HCV clearance in 16 HIV-infected patients with chronic hepatitis C (CHC, the largest case series, to our knowledge). Methods: This case series study reports the findings from 16 HIV/HCV coinfected patients with CHC who experienced spontaneous clearance of HCV infection. Patients were monitored between 2000 and 2013 in the Infectious Diseases Outpatient Clinic at the Centro Hospitalar S. João, Porto, Portugal. Results: Apart from antiretroviral therapy (ART), all patients were also consuming other potential hepatotoxic drugs (e.g., alcohol, illicit drugs, methadone, and antituberculosis medication). In all but 1 of the 16 HIV-infected patients with CHC, viral remission was associated with a temporary suspension of the ART. All patients showed a sustained HCV viral clearance. Conclusion: A possible drug-induced liver injury and/or suspension of ART may, in some cases, contribute to increasing the chances of spontaneous HCV clearance in HIV-infected patients with CHC.

Association of TNF-alpha (−308 A/G) and IFN-gamma (+874 A/T) gene polymorphisms in response to spontaneous and treatment induced viral clearance in HCV infected multitransfused thalassemic patients

BackgroundMultitransfused thalassemic individuals are at high risk of developing transfusion transmitted Hepatitis C virus (HCV) infection. The aim of the study was to correlate the effects of host cytokine single nucleotide polymorphisms of TNF-α (-308 A/G) and IFN-γ (+874 A/T) in spontaneous or IFN induced treatment response in the HCV infected thalassemic individuals. MethodsA total of 427 HCV sero-reactive thalassemic individuals were processed for HCV viral genomic diversity and host gene polymorphisms analysis of TNF-α (-308 A/G) and IFN-γ (+874 A/T). ResultsOut of 427 HCV sero-reactive individuals, 69.09% were found to be HCV RNA positive with genotype 3 as the predominant infecting strain (94.29%). Study highlighted that, A allele was significantly associated with (p < .05) spontaneous clearance of HCV infection and G allele was correlated with viral persistence at TNF-α (−308) gene polymorphism. Whereas in case of IFN-γ (+874) SNPs, A allele was significantly responsible (p < .05) for spontaneous clearance than T allele. Our study also indicated that in relapsed cases, IFN-γ (+874) T allele is more responsible than A allele. Though no significant correlation was found at both TNF-α (−308) and IFN-γ (+874) gene polymorphism among SVR and relapsed thalassemic patients. ConclusionA allele at both TNF-α (−308) and IFN-γ (+874) were strongly associated with spontaneous clearance among this population. But in case of SVR and relapsed cases no significant association was found. This cytokine gene polymorphisms pattern will help clinicians to take an informed decision about therapeutic management of HCV infected thalassemic individuals.

Repeated spontaneous clearance of hepatitis C virus infection in the setting of long-term non-progression of HIV infection.

Hepatitis C Virus (HCV) and human immunodeficiency virus (HIV) are global pandemics that affect 170 million and 35 million individuals, respectively. Up to 45% of individuals infected with HCV clear their infections spontaneously – correlating to factors like aboriginal descent and some host specific immune factors. HIV, however, establishes true latency in infected cells and cannot be cured. In the setting of longterm non-progressors (LTNPs) of HIV, a state of immune preservation and low circulating viral load is established. Regarding HIV/HCV co-infection, little is known about the relationship between spontaneous clearance of HCV infection and long-term control of HIV infection without medical intervention. We describe a case of a HIV-infected female defined as a LTNP in whom spontaneous clearance of HCV was documented on multiple occasions. Similar cases should be documented and identified in an effort to develop novel hypotheses about the natural control of these infections and inform research on immune-based interventions to control them.

Reactivation of Occult HBV Infection in Patients Cured of HCV With Direct-Acting Antivirals

The era of hepatitis C virus (HCV) treatment with direct-acting antiviral (DAA) therapy has remarkably improved liver-related morbidity and overall mortality with patients achieving rapid and sustained clearance of HCV infection. The initial DAA clinical trials excluded patients with hepatitis B virus (HBV) co-infection, and thus potential complications were unforeseen until case reports of HBV reactivation associated with DAA therapy began to emerge. A recent United States Food and Drug Administration (FDA) drug safety communication has brought public attention to the issue of HBV reactivation in patients treated with DAA for HCV co-infection. Reactivation of HBV is well known to occur with a variety of immune-suppressive therapies notably in the context of cancer, rheumatologic treatments, and organ transplantation. While HBV reactivation in the setting of DAA therapy remains rare, the severity of hepatitis can be profound and deadly. Early recognition and treatment are keys to improving patient outcomes. Therefore, it is currently recommended to screen all patients for current or prior HBV infection prior to starting DAA therapy. If either hepatitis B surface antigen (HBsAg) or hepatitis B core antibody (anti-HBc) is positive, HBV DNA should be obtained. With active viremia, prophylactic therapy should be started with DAA treatment with an agent with a high barrier for resistance. If there is no evidence of active viremia, the risks and benefits of prophylactic therapy should be weighed. Those with positive HBsAg should consider prophylactic therapy. Those with an isolated anti-HBc in the absence of HBsAg have an option of monitoring their liver enzymes, HBV DNA, and HBsAg at regular intervals during DAA therapy. If prophylactic HBV therapy is initiated, it should be continued for at least 3 months after DAA therapy is complete. After this period, the risks and benefits of continuing their HBV therapy should be re-addressed.

Broadly neutralizing antibodies with few somatic mutations and hepatitis C virus clearance.

Here, we report the isolation of broadly neutralizing mAbs (bNAbs) from persons with broadly neutralizing serum who spontaneously cleared hepatitis C virus (HCV) infection. We found that bNAbs from two donors bound the same epitope and were encoded by the same germline heavy chain variable gene segment. Remarkably, these bNAbs were encoded by antibody variable genes with sparse somatic mutations. For one of the most potent bNAbs, these somatic mutations were critical for antibody neutralizing breadth and for binding to autologous envelope variants circulating late in infection. However, somatic mutations were not necessary for binding of the bNAb unmutated ancestor to envelope proteins of early autologous transmitted/founder viruses. This study identifies a public B cell clonotype favoring early recognition of a conserved HCV epitope, proving that anti-HCV bNAbs can achieve substantial neutralizing breadth with relatively few somatic mutations, and identifies HCV envelope variants that favored selection and maturation of an anti-HCV bNAb in vivo. These data provide insight into the molecular mechanisms of immune-mediated clearance of HCV infection and present a roadmap to guide development of a vaccine capable of stimulating anti-HCV bNAbs with a physiologic number of somatic mutations characteristic of vaccine responses.

HLA-Bw4 80(T) and multiple HLA-Bw4 copies combined with KIR3DL1 associate with spontaneous clearance of HCV infection in people who inject drugs

Natural killer (NK) cell function is regulated by inhibitory and activating receptors including killer cell immunoglobulin-like receptors (KIRs). Here, we analyzed the impact of different KIR/KIR-ligand genotypes on the outcome of hepatitis C virus (HCV) infection in people who inject drugs (PWID). KIR/KIR-ligand genotypes associated with spontaneous clearance of HCV infection were identified in a cohort of PWID from Germany (n=266) and further validated in a second anti-HCV positive cohort of PWID recruited in North America (n=342). NK cells of PWID and healthy donors were functionally characterized according to their KIR/KIR-ligand genotype by flow cytometry. Multivariate logistic regression analysis revealed that KIR3DL1/HLA-Bw4 80(T) was associated with spontaneous clearance of HCV infection in PWID, which was confirmed in the PWID cohort from North America. Compared with PWID with detectable HCV RNA, the frequency of individuals with multiple HLA-Bw4 alleles was significantly higher in anti-HCV positive PWID with resolved HCV infection (29.7% vs. 15.2%; p=0.0229) and in anti-HCV seronegative PWID (39.2%; p=0.0006). KIR3DL1+ NK cells from HLA-Bw4 80(T)-positive PWID showed superior functionality compared to HLA-Bw4 80(I)-positive PWID. This differential impact was not observed in healthy donors; however, the HLA-Bw4 copy number strongly correlated with the functionality of KIR3DL1+ NK cells. HLA-Bw4-80(T) and multiple HLA-Bw4 copies in combination with KIR3DL1 are associated with protection against chronic hepatitis C in PWID by distinct mechanisms. Better licensing of KIR3DL1+ NK cells in the presence of multiple HLA-Bw4 copies is beneficial prior to seroconversion whereas HLA-Bw4 80(T) may be beneficial during acute hepatitis C. Lay summary: Natural killer (NK) cells are part of the innate immune system and are regulated by a complex network of activating and inhibiting receptors. The regulating receptor-ligand pairs of an individual are genetically determined. Here, we identified a particular set of ligand and receptor genes that are associated with better functionality of NK cells and better outcome upon exposure to HCV in a high-risk group.

Repeated Spontaneous Clearance of Hepatitis C Virus (HCV) Infection in the Setting of Long-Term Non-Progression of Human Immunodeficiency Virus (HIV) Infection

1.1.Introduction: HCV and HIV are global pandemics that affect 170 million and 35 million individuals, respectively. Up to 45% of individuals infected with HCV clear their infections spontaneously – correlating to factors like female sex, aboriginal descent, symptomatic acute hepatitis and some host specific immune factors. HIV, however, establishes true latency in infected cells, and therefore cannot be cured. In the setting of long-term non-progressors (LTNPs) of HIV, a state of immune preservation and low circulating viral load is established. Regarding HIV/HCV co- infection, little is known about the relationship between spontaneous clearance of HCV infection and long-term control of HIV infection without the benefit of antiretroviral therapy. 1.2.Case Presentation: We describe a case of a HIV-infected female who was an established LTNP in whom spontaneous clearance of HCV was documented on multiple occasions. 1.3.Conclusion: Similar cases of HIV LTNPs who may be exposed repeatedly to HCV and fail to establish productive infections should be documented and identified in an effort to develop novel hypotheses about natural control of both HIV and HCV. In the future, this could inform research on immune-based interventions to control these infections.

Spontaneous Elimination of Hepatitis C Virus Infection.

Hepatitis C virus (HCV) is the etiological agent of chronic hepatitis C and a major cause of liver cirrhosis and hepatocellular carcinoma. Only a minority of infected individuals can clear the virus spontaneously. The knowledge of the determinants of virus clearance would allow the development of effective methods preventing its further spread and optimizing treatment regimens. Viral factors associated with spontaneous virus clearance in the acute phase of infection, such as HCV genotype, virus heterogeneity, and the impact of viral proteins on the immune system have been characterized. Likewise, host genetic markers, such as the interleukin genotypes, HLA alleles, and factors affecting the T lymphocyte response appear to play an important role. Studies have revealed that natural clearance of HCV infection in the chronic phase is rare and its mechanisms are not well understood. In this review, we present the state-of-the art knowledge on the viral and host factors affecting the spontaneous elimination of HCV infection.

Incidence, risk factors, and prevention of hepatitis C reinfection: a population-based cohort study

People remain at risk of reinfection with hepatitis C virus (HCV), even after clearance of the primary infection. We identified factors associated with HCV reinfection risk in a large population-based cohort study in British Columbia, Canada, and examined the association of opioid substitution therapy and mental health counselling with reinfection. We obtained data from the British Columbia Hepatitis Testers Cohort, which includes all individuals tested for HCV or HIV at the British Columbia Centre for Disease Control Public Health Laboratory during 1990-2013 (when data were available). We defined cases of HCV reinfection as individuals with a positive HCV PCR test after either spontaneous clearance (two consecutive negative HCV PCR tests spaced ≥28 days apart without treatment) or a sustained virological response (SVR; two consecutive negative HCV PCR tests spaced ≥28 days apart 12 weeks after completing interferon-based treatment). We calculated incidence rates of HCV reinfection (per 100 person-years of follow-up) and corresponding 95% CIs assuming a Poisson distribution, and used a multivariable Cox proportional hazards model to examine reinfection risk factors (age, birth cohort, sex, year of HCV diagnosis, HCV clearance type, HIV co-infection, number of mental health counselling visits, levels of material and social deprivation, and alcohol and injection drug use), and the association of opioid substitution therapy and mental health counselling with HCV reinfection among people who inject drugs (PWID). 5915 individuals with HCV were included in this study after clearance (3690 after spontaneous clearance and 2225 after SVR). 452 (8%) patients developed reinfection; 402 (11%) after spontaneous clearance and 50 (2%) who had achieved SVR. Individuals were followed up for a median of 5·4 years (IQR 2·9-8·7), and the median time to reinfection was 3·0 years (1·5-5·4). The overall incidence rate of reinfection was 1·27 (95% CI 1·15-1·39) per 100 person-years of follow-up over a total of 35 672 person-years, with significantly higher rates in the spontaneous clearance group (1·59, 1·44-1·76) than in the SVR group (0·48, 0·36-0·63). With the adjusted Cox proportional hazards model, we noted higher reinfection risks in the spontaneous clearance group (adjusted hazard ratio [HR] 2·71, 95% CI 2·00-3·68), individuals co-infected with HIV (2·25, 1·78-2·85), and PWID (1·53, 1·21-1·92) than with other reinfection risk factors. Among the 1604 PWID with a current history of injection drug use, opioid substitution therapy was significantly associated with a lower risk of reinfection (adjusted HR 0·73, 95% CI 0·54-0·98), as was engagement with mental health counselling services (0·71, 0·54-0·92). The incidence of HCV reinfection was higher among HIV co-infected individuals, those who spontaneously cleared HCV infection, and PWID. HCV treatment complemented with opioid substitution therapy and mental health counselling could reduce HCV reinfection risk among PWID. These findings support policies of post-clearance follow-up of PWID, and provision of harm-reduction services to minimise HCV reinfection and transmission. The British Columbia Centre for Disease Control and the Canadian Institutes of Health Research.

HBV/HCV co-infection is associated with a high level of HCV spontaneous clearance among drug users and blood donors in China.

Understanding the biology of spontaneous clearance of hepatitis C virus (HCV) infection could lead to improved strategies to prevent the sequelae associated with chronic HCV infection. Chronic infections with hepatitis virus are very common in China, but the factors associated with spontaneous clearance of HCV have not been adequately studied. We evaluated the spontaneous clearance of HCV among 1918 drug users and 1526 HCV-seropositive blood donors in Guangzhou, China. Among participants who were co-infected with hepatitis B virus (HBV), 41.38% of drug users and 39.47% of blood donors had cleared their HCV infection without antiviral therapy compared to 9.41% of drug users and 16.73% of blood donors who were mono-infected with a single virus (P<.01). The proportion of subjects who had cleared their HCV infection was significantly greater in the co-infected subjects whose serum HBV DNA was greater than 2000IU/mL than those with lower levels. A multiple logistic regression analysis found female gender, IL28B rs8099917 TT genotype, HBV co-infection and blood donors (vs drug users) associated with increased spontaneous clearance of HCV infection. Although acute HCV infections are common in China, the incidence of chronic HCV may be reduced among the high prevalence of chronic HBV and IL28B genotypes associated with spontaneous clearance of HCV in Chinese populations.

Identification of the transcripts associated with spontaneous HCV clearance in individuals co-infected with HIV and HCV.

BackgroundInfection with human immunodeficiency virus (HIV) influences the outcome and natural disease progression of hepatitis C virus (HCV) infection. While the majority of HCV mono-infected and HCV/HIV co-infected subjects develop chronic HCV infection, 20–46% of mono- and co-infected subjects spontaneously clear HCV infection. The mechanism underlying viral clearance is not clearly understood. Analysis of differential cellular gene expression (mRNA) between HIV-infected patients with persistent HCV infection or spontaneous clearance could provide a unique opportunity to decipher the mechanism of HCV clearance.MethodsPlasma RNA from HIV/HCV co-infected subjects who cleared HCV and those who remained chronically infected with HCV was sequenced using Ion Torrent technology. The sequencing results were analyzed to identify transcripts that are associated with HCV clearance by measuring differential gene expression in HIV/HCV co-infected subjects who cleared HCV and those who remained chronically infected with HCV.ResultsWe have identified plasma mRNA, the levels of which are significantly elevated (at least 5 fold, False Discovery Rate (FDR) <0.05) before HCV infection in subjects who cleared HCV compared to those who remained chronically infected. Upon further analysis of these differentially expressed genes, before and after HCV infection, we found that before HCV infection 12 genes were uniquely upregulated in the clearance group compared to the chronically infected group. Importantly, a number of these 12 genes and their upstream regulators (such as CCL3, IL17D, LBP, SOCS3, NFKBIL1, IRF) are associated with innate immune response functions.ConclusionsThese results suggest that subjects who spontaneously clear HCV may express these unique genes associated with innate immune functions.

Hepatitis C virus Broadly Neutralizing Monoclonal Antibodies Isolated 25 Years after Spontaneous Clearance.

Hepatitis C virus (HCV) is world-wide a major cause of liver related morbidity and mortality. No vaccine is available to prevent HCV infection. To design an effective vaccine, understanding immunity against HCV is necessary. The memory B cell repertoire was characterized from an intravenous drug user who spontaneously cleared HCV infection 25 years ago. CD27+IgG+ memory B cells were immortalized using BCL6 and Bcl-xL. These immortalized B cells were used to study antibody-mediated immunity against the HCV E1E2 glycoproteins. Five E1E2 broadly reactive antibodies were isolated: 3 antibodies showed potent neutralization of genotype 1 to 4 using HCV pseudotyped particles, whereas the other 2 antibodies neutralized genotype 1, 2 and 3 or 1 and 2 only. All antibodies recognized non-linear epitopes on E2. Finally, except for antibody AT12-011, which recognized an epitope consisting of antigenic domain C /AR2 and AR5, all other four antibodies recognized epitope II and domain B. These data show that a subject, who spontaneously cleared HCV infection 25 years ago, still has circulating memory B cells that are able to secrete broadly neutralizing antibodies. Presence of such memory B cells strengthens the argument for undertaking the development of an HCV vaccine.

Spontaneous viral clearance of hepatitis C virus (HCV) infection among people who inject drugs (PWID) and HIV-positive men who have sex with men (HIV+ MSM): a systematic review and meta-analysis.

BackgroundHepatitis C virus (HCV) infection causes significant morbidity and mortality among people who inject drugs (PWID) and HIV+ men who have sex with men (MSM). Characterizing spontaneous viral clearance of HCV infection among PWID and HIV+ MSM is important for assessing the burden of disease and treatment strategies in these populations.MethodsElectronic and other searches of medical literature were conducted. Reports were eligible if they presented original data from upper-middle- and high-income countries on laboratory-confirmed HCV infection and spontaneous viral clearance among PWID or HIV+ MSM. Pooled estimates of spontaneous viral clearance were generated using fixed-effect and random-effects models. Meta-regression examined potential predictors related to individual characteristics and research methodology.ResultsThe meta-analysis estimated that spontaneous viral clearance occurs in 24.4 % of PWID and 15.4 % of HIV+ MSM. In univariate meta-regression among PWID, male sex and age were significantly associated with spontaneous viral clearance, and in multivariate analysis, male sex and HIV positivity were predictors of spontaneous viral clearance; among HIV+ MSM no variables were found to affect spontaneous viral clearance.ConclusionThe variability in estimates of spontaneous viral clearance between HIV+ MSM and PWID suggests the impact of HIV co-infection and HCV re-infection. Due to limited data on additional factors that may affect the natural history of HCV, more research is needed to further understand spontaneous viral clearance in these risk groups.Protocol registrationThe protocols for the PWID and HIV+ MSM research were registered with PROSPERO (CRD42014008805; CRD42013006462).Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-1807-5) contains supplementary material, which is available to authorized users.