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1.
Annu Rev Immunol ; 31: 163-94, 2013.
Article in English | MEDLINE | ID: mdl-23298212

ABSTRACT

Natural killer (NK) cells are effector cells of the innate immune system and are important in the control of viral infections. Their relevance is reflected by the multiple mechanisms evolved by viruses to evade NK cell-mediated immune responses. Over recent years, our understanding of the interplay between NK cell immunity and viral pathogenesis has improved significantly. Here, we review the role of NK cells in the control of four important viral infections in humans: cytomegalovirus, influenza virus, HIV-1, and hepatitis C virus.


Subject(s)
Killer Cells, Natural/immunology , Killer Cells, Natural/virology , Virus Diseases/immunology , Virus Diseases/virology , Animals , Cytomegalovirus Infections/immunology , Cytomegalovirus Infections/pathology , Cytomegalovirus Infections/prevention & control , HIV Infections/immunology , HIV Infections/pathology , HIV Infections/prevention & control , Hepatitis C/immunology , Hepatitis C/pathology , Hepatitis C/prevention & control , Hepatitis, Viral, Animal/immunology , Hepatitis, Viral, Animal/pathology , Hepatitis, Viral, Animal/prevention & control , Humans , Influenza, Human/immunology , Influenza, Human/pathology , Influenza, Human/prevention & control , Killer Cells, Natural/pathology , Virus Diseases/pathology
2.
Proc Natl Acad Sci U S A ; 119(11): e2112008119, 2022 03 15.
Article in English | MEDLINE | ID: mdl-35263223

ABSTRACT

SignificanceHepatitis C virus chronically infects approximately 1% of the world's population, making an effective vaccine for hepatitis C virus a major unmet public health need. The membrane-associated E1E2 envelope glycoprotein has been used in clinical studies as a vaccine candidate. However, limited neutralization breadth and difficulty in producing large amounts of homogeneous membrane-associated E1E2 have hampered efforts to develop an E1E2-based vaccine. Our previous work described the design and biochemical validation of a native-like soluble secreted form of E1E2 (sE1E2). Here, we describe the immunogenic characterization of the sE1E2 complex. sE1E2 elicited broadly neutralizing antibodies in immunized mice, with increased neutralization breadth relative to the membrane-associated E1E2, thereby validating this platform as a promising model system for vaccine development.


Subject(s)
Broadly Neutralizing Antibodies , Hepatitis C Antibodies , Hepatitis C , Immunogenicity, Vaccine , Viral Envelope Proteins , Viral Hepatitis Vaccines , Animals , Broadly Neutralizing Antibodies/biosynthesis , Broadly Neutralizing Antibodies/blood , Hepatitis C/prevention & control , Hepatitis C Antibodies/biosynthesis , Hepatitis C Antibodies/blood , Mice , Protein Multimerization , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/immunology , Viral Hepatitis Vaccines/chemistry , Viral Hepatitis Vaccines/immunology
3.
J Infect Dis ; 229(Supplement_3): S313-S315, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38466750

ABSTRACT

More than 2 million adults have hepatitis C virus (HCV) infection in the United States, and new infections continue to increase. Without treatment, HCV infection can lead to advanced liver disease and death. Treatment is recommended for nearly everyone with hepatitis C, resulting in a cure in >95% of people treated and raising the possibility of hepatitis C elimination. Testing is the first step to accessing life-saving treatment. The Centers for Disease Control and Prevention recommends hepatitis C screening for all adults, all pregnant persons, and anyone with risk; yet about one-third of people with hepatitis C remain unaware of their infection. Testing begins with a hepatitis C antibody test, followed, when reactive, by a nucleic acid test to detect HCV RNA. This antibody-first, 2-step testing strategy misses early infections and can result in incomplete diagnoses. Advancements in hepatitis C diagnostics and the US regulatory landscape have created an opportunity to include viral-first testing strategies and improve hepatitis C diagnosis. This journal supplement features 8 articles detailing challenges and opportunities for improving hepatitis C diagnostics in support of advancing hepatitis C elimination in the United States.


Subject(s)
Hepacivirus , Hepatitis C , Humans , United States/epidemiology , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepacivirus/genetics , Mass Screening/methods , Disease Eradication , Hepatitis C Antibodies/blood , Centers for Disease Control and Prevention, U.S. , RNA, Viral
4.
PLoS Pathog ; 18(11): e1010968, 2022 11.
Article in English | MEDLINE | ID: mdl-36378682

ABSTRACT

Successive episodes of hepatitis C virus (HCV) infection represent a unique natural rechallenge experiment to define correlates of long-term protective immunity and inform vaccine development. We applied a systems immunology approach to characterize longitudinal changes in the peripheral blood transcriptomic signatures in eight subjects who spontaneously resolved two successive HCV infections. Furthermore, we compared these signatures with those induced by an HCV T cell-based vaccine regimen. We identified a plasma cell transcriptomic signature during early acute HCV reinfection. This signature was absent in primary infection and following HCV vaccine boost. Spontaneous resolution of HCV reinfection was associated with rapid expansion of glycoprotein E2-specifc memory B cells in three subjects and transient increase in E2-specific neutralizing antibodies in six subjects. Concurrently, there was an increase in the breadth and magnitude of HCV-specific T cells in 7 out of 8 subjects. These results suggest a cooperative role for both antibodies and T cells in clearance of HCV reinfection and support the development of next generation HCV vaccines targeting these two arms of the immune system.


Subject(s)
Hepatitis C , Transcriptome , Viral Hepatitis Vaccines , Humans , Antibodies, Neutralizing , Hepacivirus , Hepatitis C/immunology , Hepatitis C/prevention & control , Hepatitis C Antibodies , Reinfection , Viral Envelope Proteins
5.
J Viral Hepat ; 31(2): 59-65, 2024 02.
Article in English | MEDLINE | ID: mdl-37916576

ABSTRACT

Enumeration of disease is a key management tool. Setting of targets, like for hepatitis C elimination, have deep meaning and effect. We use the case of elimination in New South Wales (NSW), Australia to examine key informants' understandings of the use of targets, and the evidence that informs them, to drive action in elimination. Twenty-eight key informants working in NSW, elsewhere in Australia and internationally in high-income countries participated in a semi-structured qualitative interview in 2022. Analysis was informed by scholarship calling for examination of the ways in which science constructs what is thought possible in action. Participants pointed to the power of quantified evidence and targets and their complex effects, and questioned the usefulness and certainty derived from these at the "pointy end" of elimination. Although a range of targets exist in global and local strategies, reaching testing targets was the assumed solution to achieving elimination. Achieving elimination was thought to require "off piste" and experimental approaches that went beyond available evidence. The different types of work that participants felt necessary for late-stage elimination may require additional metrics to explain return on investment ratios. What threshold would be used to reduce efforts in elimination was a major concern. These data indicate that understandings of the evidence underpinning elimination targets and how to achieve them are far from settled. At this point, elimination efforts may need to rely on locally produced and community-driven evidence and shift from evidence-based to evidence-making paradigm.


Subject(s)
Goals , Hepatitis C , Humans , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepatitis C/diagnosis , Australia , New South Wales/epidemiology , Hepacivirus
6.
J Viral Hepat ; 31(6): 342-356, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38433561

ABSTRACT

All-oral, direct-acting antivirals can cure hepatitis C virus (HCV) in almost all infected individuals; yet, many individuals with chronic HCV are not treated, and the incidence of acute HCV is increasing in some countries, including the United States. Strains on healthcare resources during the COVID-19 pandemic negatively impacted the progress toward the World Health Organization goal to eliminate HCV by 2030, especially among persons who inject drugs (PWID). Here, we present a holistic conceptual framework termed LOTUS (Leveraging Opportunities for Treatment/User Simplicity), designed to integrate the current HCV practice landscape and invigorate HCV treatment programs in the setting of endemic COVID-19: (A) treatment as prevention (especially among PWID), (B) recognition that HCV cure may be achieved with variable adherence with evidence supporting some forgiveness for missed doses, (C) treatment of all persons with active HCV infection (viremic), regardless of acuity, (D) minimal monitoring (MinMon) during treatment, and (E) rapid test and treat (TnT). The objective of this article is to review the current literature supporting each LOTUS petal; identify remaining gaps in knowledge or data; define the remaining barriers facing healthcare providers; and review evidence-based strategies for overcoming key barriers.


Subject(s)
Antiviral Agents , COVID-19 , Substance Abuse, Intravenous , Humans , Antiviral Agents/therapeutic use , Substance Abuse, Intravenous/complications , COVID-19/prevention & control , COVID-19/epidemiology , Hepatitis C/drug therapy , Hepatitis C/prevention & control , SARS-CoV-2 , Disease Eradication/methods , Hepatitis C, Chronic/drug therapy , Hepacivirus/drug effects
7.
MMWR Recomm Rep ; 72(4): 1-21, 2023 11 03.
Article in English | MEDLINE | ID: mdl-37906518

ABSTRACT

The elimination of hepatitis C is a national priority (https://www.hhs.gov/sites/default/files/Viral-Hepatitis-National-Strategic-Plan-2021-2025.pdf). During 2010-2021, hepatitis C virus (HCV) acute and chronic infections (hereinafter referred to as HCV infections) increased in the United States, consequences of which include cirrhosis, liver cancer, and death. Rates of acute infections more than tripled among reproductive-aged persons during this time (from 0.8 to 2.5 per 100,000 population among persons aged 20-29 years and from 0.6 to 3.5 among persons aged 30-39 years). Because acute HCV infection can lead to chronic infection, this has resulted in increasing rates of HCV infections during pregnancy. Approximately 6%-7% of perinatally exposed (i.e., exposed during pregnancy or delivery) infants and children will acquire HCV infection. Curative direct-acting antiviral therapy is approved by the Food and Drug Administration for persons aged ≥3 years. However, many perinatally infected children are not tested or linked to care. In 2020, because of continued increases in HCV infections in the United States, CDC released universal screening recommendations for adults, which included recommendations for screening for pregnant persons during each pregnancy (Schillie S, Wester C, Osborne M, Wesolowski L, Ryerson AB. CDC recommendations for hepatitis C screening among adults-United States, 2020. MMWR Recomm Rep 2020;69[No. RR-2]:1-17). This report introduces four new CDC recommendations: 1) HCV testing of all perinatally exposed infants with a nucleic acid test (NAT) for detection of HCV RNA at age 2-6 months; 2) consultation with a health care provider with expertise in pediatric hepatitis C management for all infants and children with detectable HCV RNA; 3) perinatally exposed infants and children with an undetectable HCV RNA result at or after age 2 months do not require further follow-up unless clinically warranted; and 4) a NAT for HCV RNA is recommended for perinatally exposed infants and children aged 7-17 months who previously have not been tested, and a hepatitis C virus antibody (anti-HCV) test followed by a reflex NAT for HCV RNA (when anti-HCV is reactive) is recommended for perinatally exposed children aged ≥18 months who previously have not been tested. Proper identification of perinatally infected children, referral to care, and curative treatment are critical to achieving the goal of hepatitis C elimination.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Adult , Pregnancy , Female , Child , Humans , United States/epidemiology , Infant , Antiviral Agents/therapeutic use , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/drug therapy , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepacivirus/genetics , RNA , Persistent Infection , Centers for Disease Control and Prevention, U.S.
8.
Hepatology ; 77(3): 982-996, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36056620

ABSTRACT

BACKGROUND AND AIMS: HCV evasion of neutralizing antibodies (nAb) results in viral persistence and poses challenges to the development of an urgently needed vaccine. N-linked glycosylation of viral envelope proteins is a key mechanism for such evasion. To facilitate rational vaccine design, we aimed to identify determinants of protection of conserved neutralizing epitopes. APPROACH AND RESULTS: Using a reverse evolutionary approach, we passaged genotype 1a, 1b, 2a, 3a, and 4a HCV with envelope proteins (E1 and E2) derived from chronically infected patients without selective pressure by nAb in cell culture. Compared with the original viruses, HCV recombinants, engineered to harbor substitutions identified in polyclonal cell culture-passaged viruses, showed highly increased fitness and exposure of conserved neutralizing epitopes in antigenic regions 3 and 4, associated with protection from chronic infection. Further reverse genetic studies of acquired E1/E2 substitutions identified positions 418 and 532 in the N1 and N6 glycosylation motifs, localizing to adjacent E2 areas, as key regulators of changes of the E1/E2 conformational state, which governed viral sensitivity to nAb. These effects were independent of predicted glycan occupancy. CONCLUSIONS: We show how N-linked glycosylation motifs can trigger dramatic changes in HCV sensitivity to nAb, independent of glycan occupancy. These findings aid in the understanding of HCV nAb evasion and rational vaccine design, as they can be exploited to stabilize the structurally flexible envelope proteins in an open conformation, exposing important neutralizing epitopes. Finally, this work resulted in a panel of highly fit cell culture infectious HCV recombinants.


Subject(s)
Hepatitis C , Viral Envelope Proteins , Humans , Viral Envelope Proteins/genetics , Antibodies, Neutralizing , Epitopes , Polysaccharides/metabolism , Hepatitis C/prevention & control , Hepacivirus , Hepatitis C Antibodies
9.
Bull World Health Organ ; 102(1): 7-8, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38164338

ABSTRACT

Gamal Shiha talks to Gary Humphreys about how Egypt went from being one of the highest hepatitis C-prevalence countries in the world to being on the brink of eliminating the disease.


Subject(s)
Hepatitis C , Humans , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepacivirus , Egypt/epidemiology , Prevalence
10.
Liver Int ; 44(4): 955-965, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38291807

ABSTRACT

INTRODUCTION: Viral hepatitis C (HCV) and B (HBV) were at the top of Egypt's most significant public health challenges, with an estimated 14.7% of its population having antibodies to HCV in 2008. Egypt issued an ambitious action plan in 2014 to eliminate viral hepatitis through strengthening infection control and improving patient care. In 2018, an extensive HCV mass screening campaign was conducted for the entire country's population with treating more than 4 million patients with antivirals. This study aimed to evaluate the current prevalence of viral hepatitis in Egypt after all these efforts. METHODS: A cross-sectional household cluster survey was conducted in all 27 Egyptian governorates to obtain a representative sample of Egypt's population. Subjects aged 1-70 years were interviewed using a standardised questionnaire that included demographics, viral hepatitis knowledge, previous infection and risk factors data. Laboratory testing was performed for all subjects for anti-HCV and HBsAg using chemiluminescence. Subjects positive for anti-HCV were further tested for HCV-RNA by RT-PCR. Prevalence rates were calculated by demographic groups and compared to the demographic health survey 2015 results. RESULTS: Of 20 881 subjects interviewed, 48.8% were males, 20.2% were children <15 years of age, and 53.7% were residents of rural areas. Of all subjects, 92 (0.4%) were HCV-infected, 1577 (7.6%) were anti-HCV positive and 177 (0.8%) were HBV-chronically infected, including one patient who had mixed HBV and HCV current infection. The prevalence of HCV-current and HBV chronic infections decreased by 93% and 20%, respectively, compared to 2015. CONCLUSIONS: Egypt achieved the elimination of the viral hepatitis goal. To maintain low rates of viral hepatitis, community health education, in addition to maintaining infection control and blood safety programs, is essential.


Subject(s)
Hepatitis B , Hepatitis C , Hepatitis, Viral, Human , Male , Child , Humans , Middle Aged , Female , Egypt/epidemiology , Cross-Sectional Studies , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Surveys and Questionnaires , Hepatitis C Antibodies , Prevalence , Hepatitis B Surface Antigens
11.
AIDS Care ; 36(4): 442-451, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37182220

ABSTRACT

To prevent hepatitis C virus (HCV) reinfection, within the Swiss HCVree Trial, a preventive risk reduction intervention was implemented alongside curative treatment. Formative qualitative research identified three response patterns to the intervention. This mixed-methods study's aim was to cross-validate group differences in (a) the content of sexual risk reduction goals set during intervention and (b) the extent of their behavioural change in condomless anal intercourse with non-steady partners (nsCAI), sexualised and intravenous drug use at start and six-month post-intervention. Qualitative thematic analysis was used to summarise goal setting domains. Quantitative descriptive analysis was used to evaluate group differences based on assumptions of the group descriptions. Results largely confirmed assumptions on inter-group response differences in goal setting and behaviour: as expected group 1 Avoid risks showed the lowest HCV risk profile with changes in nsCAI. Group 2 Minimize-risks and Group 3 Accept-risks showed unchanged nsCAI. Group 3 had the highest HCV risk profile. Differences in their goal preferences (1: condom use; 2 reduction blood exposure; 3 safer dating) highlight diversity in attitudes to behavioural change. Our results improve understanding of variability in intervention responses such as changes in attitudes and behaviour. This provides evidence for intervention tailoring and outcome measurement.


Subject(s)
HIV Infections , Hepatitis C , Male , Humans , Hepacivirus , HIV Infections/prevention & control , Homosexuality, Male , Reinfection , Sexual Behavior , Hepatitis C/prevention & control , Risk Reduction Behavior
12.
AIDS Care ; 36(5): 641-651, 2024 May.
Article in English | MEDLINE | ID: mdl-38091449

ABSTRACT

Little is known about biopsychosocial factors relating to pre-exposure prophylaxis (PrEP) awareness among people with either heterosexual or injection drug use HIV risk behaviors. Participants engaged in vaginal/anal sex with a person of the opposite sex (N = 515) or were people who injected drugs (PWID; N = 451) in the past 12 months from 2018-2019 in Boston, MA. We examined associations between PrEP awareness and: homelessness; perceived HIV-related stigma; country of birth; bacterial STDs, chlamydia, and/or gonorrhea in the past 12 months, lifetime hepatitis C virus (HCV) infection, sexual orientation, and poverty. More PWID (36.8%) were aware of PrEP than people with heterosexual HIV risk (28%; p = .001). Among people with heterosexual risk, homelessness (aOR = 1.99, p = .003), and among PWID: homelessness (aOR = 2.11, p = .032); bacterial STD (aOR = 2.96, p = .012); chlamydia (aOR = 6.14, p = .008); and HCV (aOR = 2.40, p < .001) were associated with increased likelihood of PrEP awareness. In the combined sample: homelessness (aOR = 2.25, p < .001); HCV (aOR = 2.18, p < .001); identifying as homosexual (aOR = 3.71, p = .036); and bisexual (aOR = 1.55, p = .016) were each associated with PrEP awareness. Although having an STD, HCV, identifying as homosexual or bisexual, and experiencing homelessness were associated with increased PrEP awareness, most participants were unaware of PrEP. Efforts to increase PrEP awareness could engage PWID and heterosexual HIV risk behavior.


Subject(s)
Drug Users , HIV Infections , Hepatitis C , Pre-Exposure Prophylaxis , Substance Abuse, Intravenous , Humans , Male , Female , Heterosexuality , HIV Infections/epidemiology , HIV Infections/prevention & control , HIV Infections/complications , Substance Abuse, Intravenous/complications , Boston/epidemiology , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepatitis C/complications , Hepacivirus
13.
Rev Med Virol ; 33(5): e2474, 2023 09.
Article in English | MEDLINE | ID: mdl-37565536

ABSTRACT

Globally, more than 58 million people are chronically infected with Hepatitis C virus (HCV) with 1.5 million new infections occurring each year. An effective vaccine for HCV is therefore a major unmet medical and public health need. Since HCV rapidly accumulates mutations, vaccines must elicit the production of broadly neutralising antibodies (bnAbs) in a reproducible fashion. Decades of research have generated a number of HCV vaccine candidates. Based on the available data and research through clinical development, a vaccine antigen based on the E1E2 glycoprotein complex appears to be the best choice, but robust induction of humoral and cellular responses leading to virus neutralisation has not yet been achieved. One issue that has arisen in developing an HCV vaccine (and many other vaccines as well) is the platform used for antigen delivery. The majority of viral vaccine trials have employed subunit vaccines. However, subunit vaccines often have limited immunogenicity, as seen for HCV, and thus multiple formats must be examined in order to elicit a robust anti-HCV immune response. Nanoparticle vaccines are gaining prominence in the field due to their ability to facilitate a controlled multivalent presentation and trafficking to lymph nodes, where they can interact with both arms of the immune system. This review discusses the potential for development of a nanoparticle-based HCV E1E2 vaccine, with an emphasis on the potential benefits of such an approach along with the major challenges facing the incorporation of E1E2 into nanoparticulate delivery systems and how those challenges can be addressed.


Subject(s)
Hepatitis C , Viral Hepatitis Vaccines , Viral Vaccines , Humans , Hepacivirus/genetics , Antibodies, Neutralizing , Viral Envelope Proteins/genetics , Hepatitis C/prevention & control
14.
BMC Public Health ; 24(1): 1055, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38622549

ABSTRACT

BACKGROUND: The World Health Organization (WHO) has outlined a set of targets to achieve eliminating hepatitis C by 2030. In May 2022, Lithuanian health authorities initiated a hepatitis C virus (HCV) screening program to start working towards elimination. In the program, bonus was given to general practitioners (GPs) to promote and conduct anti-HCV tests for two situations: (1) one time testing for individuals born in 1945-1994 and (2) annual HCV testing for persons who inject drugs or are living with human immunodeficiency virus (HIV) regardless of age. This study aimed to model the current viral hepatitis C epidemiological status in Lithuania and to outline the requirements for WHO elimination targets using the first-year HCV screening results. METHODS: Individuals were invited to participate in the anti-HCV screening by GPs during routine visits. Patients who tested positive were then referred to a gastroenterologist or infectious disease doctor for further confirmatory testing. If a patient received a positive RNA test and a fibrosis staging result of ≥ F2, the doctor prescribed direct-acting antivirals. Information on the patients screened, diagnosed, and treated was obtained from the National Health Insurance Fund. The Markov disease progression model, developed by the CDA Foundation, was used to evaluate the screening program results and HCV elimination progress in Lithuania. RESULTS: Between May 2022 and April 2023, 790,070 individuals underwent anti-HCV testing, with 11,943 individuals (1.5%) receiving positive results. Anti-HCV seroprevalence was found to be higher among males than females, 1.9% and 1.2%, respectively. Within the risk population tested, 2087 (31.1%) seropositive individuals were identified. When comparing the screening program results to WHO elimination targets through modelling, 2180 patients still need to be treated annually until 2030, along with expanding fibrosis restrictions. If an elimination approach was implemented, 1000 new infections would be prevented, while saving 150 lives and averting 90 decompensated cirrhosis cases and 110 hepatocellular carcinoma cases. CONCLUSIONS: During the first year of the Lithuanian screening program, GPs were able to screen 44% of the target population. However, the country will not meet elimination targets as it currently stands without increasing treatment levels and lifting fibrosis restrictions.


Subject(s)
Drug Users , Hepatitis C, Chronic , Hepatitis C , Substance Abuse, Intravenous , Male , Female , Humans , Aged , Lithuania/epidemiology , Antiviral Agents/therapeutic use , Seroepidemiologic Studies , Hepatitis C, Chronic/drug therapy , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepacivirus , World Health Organization , Fibrosis
15.
Proc Natl Acad Sci U S A ; 118(3)2021 01 19.
Article in English | MEDLINE | ID: mdl-33431677

ABSTRACT

Hepatitis C virus (HCV) is a major worldwide health burden, and a preventive vaccine is needed for global control or eradication of this virus. A substantial hurdle to an effective HCV vaccine is the high variability of the virus, leading to immune escape. The E1E2 glycoprotein complex contains conserved epitopes and elicits neutralizing antibody responses, making it a primary target for HCV vaccine development. However, the E1E2 transmembrane domains that are critical for native assembly make it challenging to produce this complex in a homogenous soluble form that is reflective of its state on the viral envelope. To enable rational design of an E1E2 vaccine, as well as structural characterization efforts, we have designed a soluble, secreted form of E1E2 (sE1E2). As with soluble glycoprotein designs for other viruses, it incorporates a scaffold to enforce assembly in the absence of the transmembrane domains, along with a furin cleavage site to permit native-like heterodimerization. This sE1E2 was found to assemble into a form closer to its expected size than full-length E1E2. Preservation of native structural elements was confirmed by high-affinity binding to a panel of conformationally specific monoclonal antibodies, including two neutralizing antibodies specific to native E1E2 and to its primary receptor, CD81. Finally, sE1E2 was found to elicit robust neutralizing antibodies in vivo. This designed sE1E2 can both provide insights into the determinants of native E1E2 assembly and serve as a platform for production of E1E2 for future structural and vaccine studies, enabling rational optimization of an E1E2-based antigen.


Subject(s)
Hepacivirus/drug effects , Hepatitis C Antibodies/biosynthesis , Hepatitis C/prevention & control , Viral Envelope Proteins/immunology , Viral Hepatitis Vaccines/immunology , Animals , Antibodies, Monoclonal/biosynthesis , Antibodies, Neutralizing/biosynthesis , Epitope Mapping , Epitopes/chemistry , Epitopes/immunology , Female , Gene Expression , Hepacivirus/immunology , Hepacivirus/pathogenicity , Hepatitis C/immunology , Hepatitis C/pathology , Hepatitis C/virology , Humans , Immunogenicity, Vaccine , Mice , Models, Molecular , Protein Binding , Protein Conformation , Protein Engineering/methods , Protein Multimerization , Receptors, Virus/genetics , Receptors, Virus/immunology , Recombinant Proteins/administration & dosage , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Solubility , Tetraspanin 28/genetics , Tetraspanin 28/immunology , Vaccination , Viral Envelope Proteins/administration & dosage , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/genetics , Viral Hepatitis Vaccines/administration & dosage , Viral Hepatitis Vaccines/chemistry , Viral Hepatitis Vaccines/genetics
16.
Harm Reduct J ; 21(1): 25, 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38281942

ABSTRACT

BACKGROUND: Due to shared modes of transmission, coinfection with hepatitis B virus (HBV) and hepatitis C virus (HCV) is common, and HBV vaccination is recommended for all persons with HCV who remain susceptible to HBV. To identify potential gaps in HBV vaccination among this high-risk population, we aimed to determine the patterns of HBV susceptibility in persons undergoing community-based HCV treatment. METHODS: We performed a cross-sectional study within two community-based HCV treatment programs in an urban US setting. Participants were identified for HCV screening and confirmatory testing via street-outreach recruitment directed at persons experiencing homelessness and currently using drugs. Participants were excluded if HBsAg was reactive. Cohort characteristics were obtained via intake surveys and descriptive analysis was performed by exposure status. RESULTS: Among 150 participants without chronic HBV receiving community-based HCV treatment, 43% had evidence of prior HBV infection, 26% were immune from vaccination, and 31% were non-immune. Among the subset of the cohort reporting current injection drug use (IDU) (N = 100), 31% (n = 10) of those aged 24-40 and 47% (n = 23) of those aged 41-57 remained susceptible to HBV infection. By contrast only two participants aged 58-74 were HBV non-immune (11%), with 84% immune due to prior exposure. CONCLUSIONS: Our data reflect a high prevalence of HBV susceptibility among persons undergoing community-based HCV treatment. Although younger patients were more likely to be immune due to vaccination, a high proportion remained non-immune to HBV, particularly among those reporting current IDU. Our data reflect a gap in HBV vaccination among younger persons with HCV and suggest a potential role for co-localizing HBV vaccination with community-based HCV screening and treatment.


Subject(s)
Hepatitis B , Hepatitis C , Humans , Hepatitis B virus , Hepacivirus , Prevalence , Cross-Sectional Studies , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Hepatitis B/epidemiology , Hepatitis B/prevention & control
17.
J Formos Med Assoc ; 123(5): 613-619, 2024 May.
Article in English | MEDLINE | ID: mdl-38195318

ABSTRACT

BACKGROUND: /Purpose: To achieve the World Health Organization goal of eliminating viral hepatitis by 2030, a key strategy in resource-limited areas is to identify the areas with high prevalence and to prioritize screening and treatment intervention. We hypothesized that a hospital-based laboratory database could be used to estimate the township- and village-specific anti-hepatitis C virus (HCV) prevalence. METHODS: Yunlin County Public Health Bureau has been collecting anti-HCV test data from eight major hospitals. Township- and village-specific screening testing rates and anti-HCV prevalence were calculated for residents 40 years or older. A township with a wide range of anti-HCV prevalence rates was selected for outreach universal screening and for validating the village-specific prevalence of anti-HCV in the analysis of the data from the hospitals. RESULTS: The overall anti-HCV screening testing rate in Yunlin County was 30.4 %, whereas the anti-HCV prevalence rate for persons 40 years or older was 15.4 %. The village-specific anti-HCV prevalence rates ranged from 3.8 % to 85.8 %. Community-based screening was conducted in Kouhu Township. The village-specific anti-HCV prevalence rates ranged from 0 % to 18.8 %. Three of the four villages had the highest village-specific anti-HCV prevalence in the community-based study and the hospital-based study. Additionally, 95.8 % of the new HCV cases detected by universal screening received anti-HCV therapy. CONCLUSION: The hospital-based database provided a framework for identifying the villages with high anti-HCV prevalence. Additionally, community-based universal screening should be prioritized for villages with high prevalence in hospital-based databases.


Subject(s)
Hepatitis C , Mass Screening , Humans , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Prevalence , Adult , Middle Aged , Female , Aged , Male , Hepatitis C Antibodies/blood , Hospitals/statistics & numerical data , Hepacivirus/immunology , Rural Population/statistics & numerical data
18.
J Public Health Manag Pract ; 30(2): 208-212, 2024.
Article in English | MEDLINE | ID: mdl-37594263

ABSTRACT

The US government has established a national goal of hepatitis C virus (HCV) elimination by 2030. To date, most HCV elimination planning and activity have been at the state level. Fifteen states presently have publicly available HCV elimination plans. In 2019, Louisiana and Washington were the first states to initiate 5-year funded HCV elimination programs. These states differ on motivation for pursuing HCV elimination and ranking on several indicators. Simultaneously, however, they have emphasized several similar elimination components including HCV screening promotion through public awareness, screening expansion, surveillance enhancement (including electronic reporting and task force development), and harm reduction. The 13 other states with published elimination plans have proposed the majority of the elements identified by Louisiana and Washington, but several have notable gaps. Louisiana's and Washington's comprehensive plans, funding approaches, and programs provide a useful framework that can move states and the nation toward HCV elimination.


Subject(s)
Hepacivirus , Hepatitis C , Humans , Washington , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Louisiana/epidemiology , Mass Screening
19.
J Infect Dis ; 228(Suppl 3): S154-S159, 2023 09 13.
Article in English | MEDLINE | ID: mdl-37703339

ABSTRACT

Nonprofit and nongovernmental organizations have driven and continue to drive hepatitis C elimination by putting people with viral hepatitis and their affected communities at the center of hepatitis elimination efforts. They have been key in driving the decentralization of services and community-based delivery in the hepatitis care pathway to improve the health and well-being of the populations most affected by hepatitis C. This article explores how the formation of the World Hepatitis Alliance (WHA), an international network of community organizations in >100 countries, led to powerful advocacy from community leaders and people with hepatitis, resulting in the establishment of World Hepatitis Day. Since then, the World Health Organization (WHO) has recognized the importance of viral hepatitis by setting the 2030 global elimination targets. WHA and WHO have collaborated on 3 World Hepatitis Summits, which have built momentum across many sectors to help elevate hepatitis through the global health agenda. The article discusses their paradigm-shifting campaigns and also presents civil society organizations' hepatitis elimination efforts in Egypt, Mongolia, Bangladesh, and the United Kingdom and their significant impact through local resource mobilization and engagement of national governments.


Subject(s)
Hepatitis A , Hepatitis C , Humans , Hepacivirus , Organizations, Nonprofit , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Bangladesh
20.
J Infect Dis ; 228(6): 684-693, 2023 09 15.
Article in English | MEDLINE | ID: mdl-36932731

ABSTRACT

BACKGROUND: The country of Georgia initiated its hepatitis C virus (HCV) elimination program in 2015, at which point a serosurvey showed the adult prevalence of HCV antibody (anti-HCV) and HCV RNA to be 7.7% and 5.4%, respectively. This analysis reports hepatitis C results of a follow-up serosurvey conducted in 2021, and progress towards elimination. METHODS: The serosurvey used a stratified, multistage cluster design with systematic sampling to include adults and children (aged 5-17 years) providing consent (or assent with parental consent). Blood samples were tested for anti-HCV and if positive, HCV RNA. Weighted proportions and 95% confidence intervals (CI) were compared with 2015 age-adjusted estimates. RESULTS: Overall, 7237 adults and 1473 children were surveyed. Among adults, the prevalence of anti-HCV was 6.8% (95% CI, 5.9-7.7). The HCV RNA prevalence was 1.8% (95% CI, 1.3-2.4), representing a 67% reduction since 2015. HCV RNA prevalence decreased among those reporting risk factors of ever injecting drugs (51.1% to 17.8%), and ever receiving a blood transfusion (13.1% to 3.8%; both P < .001). No children tested positive for anti-HCV or HCV RNA. CONCLUSIONS: These results demonstrate substantial progress made in Georgia since 2015. These findings can inform strategies to meet HCV elimination targets.


Subject(s)
Hepacivirus , Hepatitis C , Adult , Humans , Hepacivirus/genetics , Georgia/epidemiology , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Risk Factors , RNA , Prevalence
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