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1.
Hepatology ; 75(1): 182-195, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34396571

RESUMO

BACKGROUND AND AIM: HBV DNA can be reduced using antiviral drugs in patients with chronic hepatitis B (CHB); however, the rate of HBeAg seroconversion remains low. A clinical trial was conducted to assess the efficacy and safety of a de novo designed liposome-based nanoparticle lipopeptide vaccine, εPA-44, for CHB. APPROACH AND RESULTS: A two-stage phase 2 trial, which included a 76-week, randomized, double-blind, placebo-controlled trial (stage 1) and a 68-week open-label extension (stage 2), was conducted in 15 centers across China (Clinicaltrials.gov No. NCT00869778). In stage 1, 360 human leukocyte antigen A2 (HLA-A2)-positive and HBeAg-positive patients were randomly and equally distributed to receive six subcutaneous injections of 600 µg or 900 µg εPA-44 or placebo at week 0, 4, 8, 12, 20, and 28. In stage 2, 183 patients received extended 900 µg εPA-44, and 26 patients were observed for relapse without further treatment. The primary endpoint was the percentage of patients with HBeAg seroconversion at week 76. At week 76, patients receiving 900 µg εPA-44 achieved significantly higher HBeAg seroconversion rate (38.8%) versus placebo (20.2%) (95% CI, 6.9-29.6%; p = 0.002). With a combined endpoint of HBeAg seroconversion, alanine aminotransferase normalization and HBV DNA < 2,000 IU/mL, both 900 µg (18.1%) and 600 µg (14.3%), resulted in significantly higher rate versus placebo (5.0%) (p = 0.002 and p = 0.02, respectively) at week 76. In stage 2, none (0 of 20) of 900 µg εPA-44-treated patients experienced serologic relapse. The safety profile of εPA-44 was comparable to that of placebo. CONCLUSIONS: Among HLA-A2-positive patients with progressive CHB, a finite duration of 900 µg εPA-44 monotherapy resulted in significantly higher HBeAg seroconversion rate than placebo and sustained off-treatment effect. A phase 3 trial is ongoing (ChiCTR2100043708).


Assuntos
Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/terapia , Vacinas contra Hepatite Viral/administração & dosagem , Adolescente , Adulto , Método Duplo-Cego , Feminino , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Injeções Subcutâneas , Lipossomos , Masculino , Sistemas de Liberação de Fármacos por Nanopartículas , Soroconversão , Resposta Viral Sustentada , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos , Vacinas de Subunidades Antigênicas/química , Vacinas contra Hepatite Viral/efeitos adversos , Vacinas contra Hepatite Viral/química , Adulto Jovem
2.
Sci Rep ; 11(1): 21856, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34750487

RESUMO

Hepatitis C is a major threat to public health for which an effective treatment is available, but a prophylactic vaccine is still needed to control this disease. We designed a vaccine based on chimeric HBV-HCV envelope proteins forming subviral particles (SVPs) that induce neutralizing antibodies against HCV in vitro. Here, we aimed to increase the neutralizing potential of those antibodies, by using HBV-HCV SVPs bearing apolipoprotein E (apoE). These particles were produced by cultured stable mammalian cell clones, purified and characterized. We found that apoE was able to interact with both chimeric HBV-HCV (E1-S and E2-S) proteins, and with the wild-type HBV S protein. ApoE was also detected on the surface of purified SVPs and improved the folding of HCV envelope proteins, but its presence lowered the incorporation of E2-S protein. Immunization of New Zealand rabbits resulted in similar anti-S responses for all rabbits, whereas anti-E1/-E2 antibody titers varied according to the presence or absence of apoE. Regarding the neutralizing potential of these anti-E1/-E2 antibodies, it was higher in rabbits immunized with apoE-bearing particles. In conclusion, the association of apoE with HCV envelope proteins may be a good strategy for improving HCV vaccines based on viral envelope proteins.


Assuntos
Apolipoproteínas E/administração & dosagem , Apolipoproteínas E/imunologia , Hepacivirus/imunologia , Vírus da Hepatite B/imunologia , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/imunologia , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/sangue , Apresentação de Antígeno/imunologia , Linhagem Celular , Feminino , Hepatite C/imunologia , Hepatite C/prevenção & controle , Anticorpos Anti-Hepatite C/biossíntese , Anticorpos Anti-Hepatite C/sangue , Humanos , Evasão da Resposta Imune , Coelhos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/imunologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/imunologia
3.
Viruses ; 13(6)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070543

RESUMO

Development of preventive vaccines against hepatitis C virus (HCV) remains one of the main strategies in achieving global elimination of the disease. The effort is focused on the quest for vaccines capable of inducing protective cross-neutralizing humoral and cellular immune responses, which in turn dictate the need for rationally designed cross-genotype vaccine antigens and potent immunoadjuvants systems. This review provides an assessment of the current state of knowledge on immunopotentiating compounds and vaccine delivery systems capable of enhancing HCV antigen-specific immune responses, while focusing on the synergy and interplay of two modalities. Structural, physico-chemical, and biophysical features of these systems are discussed in conjunction with the analysis of their in vivo performance. Extreme genetic diversity of HCV-a well-known hurdle in the development of an HCV vaccine, may also present a challenge in a search for an effective immunoadjuvant, as the effort necessitates systematic and comparative screening of rationally designed antigenic constructs. The progress may be accelerated if the preference is given to well-defined molecular immunoadjuvants with greater formulation flexibility and adaptability, including those capable of spontaneous self-assembly behavior, while maintaining their robust immunopotentiating and delivery capabilities.


Assuntos
Sistemas de Liberação de Medicamentos , Hepacivirus/imunologia , Hepatite C/prevenção & controle , Imunogenicidade da Vacina , Vacinas contra Hepatite Viral/imunologia , Adjuvantes Imunológicos , Animais , Ensaios Clínicos como Assunto , Composição de Medicamentos , Hepatite C/imunologia , Humanos , Nanopartículas , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/química
4.
BMC Infect Dis ; 21(1): 508, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059011

RESUMO

BACKGROUND: Hepatitis B and C infections and transmission are a serious challenge to all healthcare systems. We studied seroprevalence rates of Transfusion Transmitted Diseases (TTD) among blood bank donors in Jordan from 2014 to 2019 as a follow-up study of our previously published work. In addition, we wanted to explore the efficacy of the mandatory vaccination of infants against hepatitis B virus (HBV) which was implemented by the Ministry of Health since 1995 for the eradication of HBV infection in Jordan. METHODS: We reviewed blood bank donors' records at King Hussein Cancer Center (KHCC) from January 1st, 2014, until December 31st, 2019. Results of seropositivity prevalence rates for HBsAg, anti-HBcore, and anti-HCV, using Enzyme-Linked ImmunoSorbent Assay (ELISA) were compared to seropositivity rates from our previously published data. In addition, our results were compared to data obtained from other blood banks in Jordan, as well as compared to published information from blood banks in neighboring countries. RESULTS: The prevalence rates (%) of seropositive blood donors for viral hepatitis for the years 2014, 2015, 2016, 2017, 2018, and 2019, were as follows: HBsAg rates were 0.3386, 0.2108, 0.1801, 0.1898, 0.2068, and 0.2741; anti-HBcore rates were 4.1112, 3.2271, 2.9748, 2.8405, 2.6879 and 3.0986; and anti-HCV rates were 0.1129, 0.0486, 0.0548, 0.0654, 0.0782, and 0.0839, respectively. There was a significant increase in the prevalence of HBsAg, Anti-HBcore and Anti-HCV antibodies in 2019 (one sample z-score test, p < 0.00001). CONCLUSIONS: Prevalence rates of hepatitis B and C infections among Jordanian blood bank donors showed a steady decline between 2009 and 2017, and these rates were much lower in Jordan than in neighboring countries. However, an increase in the prevalence rates of hepatitis B and C infections among blood bank donors was documented in 2019. While the reasons for this increase are not clear yet, these findings highlight the importance of renewed efforts to increase public health awareness of HBV and implement effective measures to prevent the transmission and infection with HBV, including national vaccination programs.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Reação Transfusional/epidemiologia , Bancos de Sangue/estatística & dados numéricos , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Anticorpos Anti-Hepatite C/sangue , Humanos , Jordânia/epidemiologia , Prevalência , Estudos Soroepidemiológicos , Reação Transfusional/sangue , Reação Transfusional/prevenção & controle , Reação Transfusional/virologia , Vacinas contra Hepatite Viral/administração & dosagem
5.
J Hepatol ; 74(6): 1315-1324, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33845058

RESUMO

BACKGROUND & AIMS: Rat hepatitis E virus (Orthohepevirus species C; HEV-C1) is an emerging cause of viral hepatitis in humans. HEV-C1 is divergent from other HEV variants infecting humans that belong to Orthohepevirus species A (HEV-A). This study assessed HEV-C1 antigenic divergence from HEV-A and investigated the impact of this divergence on infection susceptibility, serological test sensitivity, and vaccine efficacy. METHODS: Immunodominant E2s peptide sequences of HEV-A and HEV-C1 were aligned. Interactions of HEV-C1 E2s and anti-HEV-A monoclonal antibodies (mAbs) were modeled. Recombinant peptides incorporating E2s of HEV-A (HEV-A4 p239) and HEV-C1 (HEV-C1 p241) were expressed. HEV-A and HEV-C1 patient sera were tested using antibody enzymatic immunoassays (EIA), antigen EIAs, and HEV-A4 p239/HEV-C1 p241 immunoblots. Rats immunized with HEV-A1 p239 vaccine (Hecolin), HEV-A4 p239 or HEV-C1 p241 peptides were challenged with a HEV-C1 strain. RESULTS: E2s sequence identity between HEV-A and HEV-C1 was only 48%. There was low conservation at E2s residues (23/53; 43.4%) involved in mAb binding. Anti-HEV-A mAbs bound HEV-C1 poorly in homology modeling and antigen EIAs. Divergence resulted in low sensitivity of commercial antigen (0%) and antibody EIAs (10-70%) for HEV-C1 diagnosis. Species-specific HEV-A4 p239/HEV-C1 p241 immunoblots accurately differentiated HEV-A and HEV-C1 serological profiles in immunized rats (18/18; 100%) and infected-patient sera (32/36; 88.9%). Immunization with Hecolin and HEV-A4 p239 was partially protective while HEV-C1 p241 was fully protective against HEV-C1 infection in rats. CONCLUSIONS: Antigenic divergence significantly decreases sensitivity of hepatitis E serodiagnostic assays for HEV-C1 infection. Species-specific immunoblots are useful for diagnosing HEV-C1 and for differentiating the serological profiles of HEV-A and HEV-C1. Prior HEV-A exposure is not protective against HEV-C1. HEV-C1 p241 is an immunogenic vaccine candidate against HEV-C1. LAY SUMMARY: Rat hepatitis E virus (HEV-C1) is a new cause of hepatitis in humans. Using a combination of methods, we showed that HEV-C1 is highly divergent from the usual cause of human hepatitis (HEV-A). This divergence reduces the capacity of existing tests to diagnose HEV-C1 and also indicates that prior exposure to HEV-A (via infection or vaccination) is not protective against HEV-C1.


Assuntos
Antígenos de Hepatite/imunologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Hepatite E/prevenção & controle , Hepatite E/veterinária , Imunogenicidade da Vacina/imunologia , Vacinação/métodos , Eficácia de Vacinas , Vacinas Sintéticas/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Sequência de Bases , Criança , Epitopos/imunologia , Feminino , Genótipo , Anticorpos Anti-Hepatite/imunologia , Hepatite E/sangue , Hepatite E/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Adulto Jovem
6.
Emerg Microbes Infect ; 10(1): 365-375, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33583360

RESUMO

Concerns about vaccine safety are an important reason for vaccine hesitancy, however, limited information is available on whether common adverse reactions following vaccination affect the immune response. Data from three clinical trials of recombinant vaccines were used in this post hoc analysis to assess the correlation between inflammation-related solicited adverse reactions (ISARs, including local pain, redness, swelling or induration and systematic fever) and immune responses after vaccination. In the phase III trial of the bivalent HPV-16/18 vaccine (Cecolin®), the geometric mean concentrations (GMCs) for IgG anti-HPV-16 and -18 (P<0.001) were significantly higher in participants with any ISAR following vaccination than in those without an ISAR. Local pain, induration, swelling and systemic fever were significantly correlated with higher GMCs for IgG anti-HPV-16 and/or anti-HPV-18, respectively. Furthermore, the analyses of the immunogenicity bridging study of Cecolin® and the phase III trial of a hepatitis E vaccine yielded similar results. Based on these results, we built a scoring model to quantify the inflammation reactions and found that the high score of ISAR indicates the strong vaccine-induced antibody level. In conclusion, this study suggests inflammation-related adverse reactions following vaccination potentially indicate a stronger immune response.


Assuntos
Hepatite E/imunologia , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Infecções por Papillomavirus/imunologia , Vacinas contra Papillomavirus/imunologia , Vacinas Sintéticas/imunologia , Vacinas contra Hepatite Viral/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/imunologia , Feminino , Hepatite E/prevenção & controle , Hepatite E/virologia , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Imunidade , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/efeitos adversos , Vacinas contra Papillomavirus/genética , Vacinação/efeitos adversos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/efeitos adversos , Vacinas contra Hepatite Viral/genética , Adulto Jovem
7.
Proc Natl Acad Sci U S A ; 118(3)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33431677

RESUMO

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.


Assuntos
Hepacivirus/efeitos dos fármacos , Anticorpos Anti-Hepatite C/biossíntese , Hepatite C/prevenção & controle , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Neutralizantes/biossíntese , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Feminino , Expressão Gênica , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C/imunologia , Hepatite C/patologia , Hepatite C/virologia , Humanos , Imunogenicidade da Vacina , Camundongos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Engenharia de Proteínas/métodos , Multimerização Proteica , Receptores Virais/genética , Receptores Virais/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Solubilidade , Tetraspanina 28/genética , Tetraspanina 28/imunologia , Vacinação , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/química , Vacinas contra Hepatite Viral/genética
8.
Kaohsiung J Med Sci ; 37(4): 262-267, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33502828

RESUMO

Over the past decades, marked advancement has been made in the prevention and treatment of hepatitis B virus (HBV) infection. Due to highly effective antiviral therapies for chronic hepatitis B (CHB), long-term clinical outcomes in patients with CHB has also been dramatically improved. However, current antiviral therapies for CHB cannot completely abolish the risk of hepatocellular carcinoma (HCC). In addition, current treatment guidelines for CHB should be interpreted with caution given that HBV-associated hepatocarcinogenesis could be underway in patients who are not eligible for antiviral therapies by current guidelines. Therefore, efforts to reconcile treatment guidelines with recent clinical evidence should be made for reducing further development of HCC. In this article, we review the secondary prevention of HBV-related HCC with current antiviral therapies.


Assuntos
Carcinogênese/efeitos dos fármacos , Carcinoma Hepatocelular/prevenção & controle , DNA Viral/imunologia , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Prevenção Secundária/métodos , Antivirais/uso terapêutico , Carcinogênese/genética , Carcinogênese/imunologia , Carcinogênese/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , DNA Viral/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Guias de Prática Clínica como Assunto , Recidiva , Fatores de Risco , Vacinas contra Hepatite Viral/administração & dosagem
9.
Mol Pharm ; 18(2): 726-734, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32530637

RESUMO

Two well-defined synthetic polyphosphazene immunoadjuvants, PCPP and PCEP, were studied for their ability to potentiate the immune response to the hepatitis C virus (HCV) E2 glycoprotein antigen in vivo. We report that PCEP induced significantly higher serum neutralization and HCV-specific IgG titers in mice compared to other adjuvants used in the study: PCPP, Alum, and Addavax. PCEP also shifted the response toward the desirable balanced Th1/Th2 immunity, as evaluated by the antibody isotype ratio (IgG2a/IgG1). The in vivo results were analyzed in the context of antigen-adjuvant molecular interactions in the system and in vitro immunostimulatory activity of formulations. Asymmetric flow field flow fractionation (AF4) and dynamic light scattering (DLS) analysis showed that both PCPP and PCEP spontaneously self-assemble with the E2 glycoprotein with the formation of multimeric water-soluble complexes, which demonstrates the role of polyphosphazene macromolecules as vaccine delivery vehicles. Intrinsic in vitro immunostimulatory activity of polyphosphazene adjuvants, which was assessed using a mouse macrophage cell line, revealed comparable activities of both polymers and did not provide an explanation of their in vivo performance. However, PCEP complexes with E2 displayed greater stability against agglomeration and improved in vitro immunostimulatory activity compared to those of PCPP, which is in line with superior in vivo performance of PCEP. The results emphasize the importance of often neglected antigen-polyphosphazene self-assembly mechanisms in formulations, which can provide important insights on their in vivo behavior and facilitate the establishment of a structure-activity relationship for this important class of immunoadjuvants.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos da Hepatite C/administração & dosagem , Hepatite C/prevenção & controle , Proteínas do Envelope Viral/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Feminino , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Antígenos da Hepatite C/imunologia , Antígenos da Hepatite C/ultraestrutura , Humanos , Imunogenicidade da Vacina , Camundongos , Modelos Animais , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/imunologia , Polímeros/administração & dosagem , Polímeros/química , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/ultraestrutura , Relação Estrutura-Atividade , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/isolamento & purificação , Proteínas do Envelope Viral/ultraestrutura , Vacinas contra Hepatite Viral/imunologia
10.
BMC Infect Dis ; 20(1): 806, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129259

RESUMO

BACKGROUND: This study aimed at determining the prevalence of and risk factors for hepatitis B virus (HBV) and hepatitis C virus (HCV) among incarcerated people who inject drugs (PWID) in Iran in 2015-16. METHODS: The required data was collected from a database provided by Iranian national bio-behavioral surveillance surveys (BBSSs) on 11,988 prisoners selected from among 55 prisons in 19 provinces in 2015-16. The data on demographics and behavioral variables were collected through interviews and the status of exposure to HBV and HCV were determined using ELISA blood test. A total of 1387 individuals with a history of drug injection in their lifetime were enrolled into the study. Data were analyzed using the survey package in Stata/SE software, Version 14.0. Univariate and multivariate logistic regression tests were used to investigate the relationships between risk factors and outcomes. RESULTS: The mean age of the incarcerated PWID was 36.83 ± 8.13 years. Of all the studied subjects, 98.46% were male and 50.97% were married. The prevalence of HCV and HBV among the subjects were 40.52 and 2.46%, respectively. The prevalence of HCV was associated with age ≥ 30 years, being single, illiteracy and low level of education, prison term> 5 years, history of piercing, and extramarital sex in lifetime (P < 0.05). CONCLUSIONS: The prevalence of HCV is alarmingly high. In general, it is recommended to adopt measures to screen and treat patients with HCV and vaccinat incarcerated PWID without a history of vaccination against HBV.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Prisioneiros , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Estudos Transversais , Feminino , Hepacivirus , Hepatite B/complicações , Hepatite B/prevenção & controle , Vírus da Hepatite B , Hepatite C/complicações , Hepatite C/prevenção & controle , Humanos , Irã (Geográfico)/epidemiologia , Modelos Logísticos , Masculino , Prevalência , Prisioneiros/estatística & dados numéricos , Prisões , Fatores de Risco , Vacinas contra Hepatite Viral/administração & dosagem
11.
APMIS ; 128(11): 593-602, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32870528

RESUMO

Induction of broad Th1 cellular immune responses and cytokines is crucial characteristics for vaccines against intracellular infections such as hepatitis C virus (HCV). Plants (especially oilseed tissues) and plant-immunomodulators (like oil bodies) offer cost-effective and scalable possibilities for the production of immunologically relevant and safe vaccine antigens and adjuvants, respectively. Herein, we provide data of the murine immunization by transgenic canola oilseed-derived HCV core protein (HCVcp) soluble extract (TSE) and Escherichia coli- derived rHCVcp in combination with Canola oil bodies (oil) compared to that of the Freund's (FA) adjuvant. Mice immunized by TSE+ oil developed both strong humeral (IgG) and Th1-biased cellular responses, manifested by high levels of IFN-γ and lower IgG1/IgG2a ratio and IL-4 secretion. Results of the intracellular cytokine staining indicated that TSE+ oil immunization in mice triggered both CD4+ and CD8+ T cells to release IFN-γ, while CD4+ cells were mostly triggered when FA was used. Analyses by qRT-PCR indicated that a combination of rHCVcp/TSE with oil body induced high levels of IL-10 cytokines compared to that of the FA adjuvant. These characteristics are important properties for the design of an HCV vaccine candidate and indicate the potential of Canola-derived antigen and oil bodies in addressing these concerns.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/prevenção & controle , Proteínas Recombinantes/administração & dosagem , Células Th1/efeitos dos fármacos , Proteínas do Core Viral/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Imunidade Celular/efeitos dos fármacos , Imunoglobulina G/biossíntese , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Óleo de Brassica napus/administração & dosagem , Óleo de Brassica napus/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Células Th1/imunologia , Células Th1/virologia , Proteínas do Core Viral/biossíntese , Proteínas do Core Viral/imunologia , Vacinas contra Hepatite Viral/biossíntese
12.
Viruses ; 12(8)2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731536

RESUMO

Hepatitis B virus (HBV) infection and its related liver diseases are important health problems worldwide, particularly in the Asia-Pacific region. For the past 4-5 decades, Taiwan's government and scientists have cooperated together to control this virus infection and its related liver diseases. These efforts and achievements have made progress toward the elimination of HBV. Taiwan's government initiated the Viral Hepatitis Control Program (VHCP) in the1970s, and then launched the national vaccination program in 1984. This universal vaccination program effectively decreased the rate of hepatitis B carriage and the development of hepatocellular carcinoma (HCC) in the younger generation. Since 2003, approved anti-HBV treatments were reimbursed nationwide. This reimbursement program resulted in a higher uptake of anti-HBV treatments, which contributed to a decrease in liver-related disease progression and subsequently reduced attributable mortality in Taiwan. This experience can be shared by countries in other parts of the world regarding the control of chronic viral hepatitis B.


Assuntos
Erradicação de Doenças , Hepatite B Crônica/prevenção & controle , Programas de Imunização , Carcinoma Hepatocelular/virologia , Feminino , Hepatite B Crônica/epidemiologia , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Neoplasias Hepáticas/virologia , Masculino , Taiwan/epidemiologia , Vacinação , Vacinas contra Hepatite Viral/administração & dosagem
14.
Virus Res ; 284: 197984, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32325116

RESUMO

Hepatitis C virus (HCV) can cause chronic infection and evade the immune response. The generation and maintenance of an effective T-cell response is important for immune-mediated control of HCV infection. The purpose of this study was to obtain recombinant mosaic proteins containing the cytotoxic T lymphocyte (CTL) epitopes of HCV fused with different adjuvants and analyse their immunogenicity. A recombinant polyepitope protein comprising HLA-A2-restricted CTL epitopes of the NS3, NS4ab and NS5a proteins of HCV was designed. Adjuvant compounds, the T-helper (Th) epitope PADRE, lipopeptide from Neisseria meningiditis and interleukin 2 (IL-2) were included in the fusion proteins. Three proteins differing in their adjuvant content were expressed in Escherichia coli and purified. The purified proteins formed nanosized particles. The proteins were characterized by their ability to cause proliferation of spleen cells, induce expression of cytokine genes and production of interferon gamma by T lymphocytes of immunized mice. The obtained recombinant vaccine proteins effectively stimulate dendritic cells, which in turn specifically activate Th1 and Th2 lymphocytes. Adjuvant components act additively to enhance the stimulation of dendritic cells and polarize them in the direction of Th1 lymphocyte activation. Analysis of spleen cell proliferation, expression of Th1 and Th2 cytokines and production of interferon gamma by lymphocytes of immunized mice after specific stimulation in vitro revealed that recombinant protein comprising CTL epitopes of HCV, Th epitope PADRE, lipoprotein and IL-2 induced the highest response of T-lymphocytes.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Epitopos de Linfócito T/imunologia , Hepacivirus/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinas contra Hepatite Viral/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia , Adjuvantes Imunológicos/química , Animais , Citocinas/análise , Citocinas/imunologia , Hepacivirus/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Células Th1/imunologia , Células Th2/imunologia , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/genética , Proteínas não Estruturais Virais/administração & dosagem
16.
Hepatology ; 72(5): 1541-1555, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32012325

RESUMO

BACKGROUND AND AIMS: Induction of functional helper CD4+ T cells is the hallmark of a protective immune response against hepatitis C virus (HCV), associated with spontaneous viral clearance. Heterologous prime/boost viral vectored vaccination has demonstrated induction of broad and polyfunctional HCV-specific CD8+ T cells in healthy volunteers; however, much less is known about CD4+ T-cell subsets following vaccination. APPROACH AND RESULTS: We analyzed HCV-specific CD4+ T-cell populations using major histocompatibility complex class II tetramers in volunteers undergoing HCV vaccination with recombinant HCV adenoviral/modified vaccinia Ankara viral vectors. Peptide-specific T-cell responses were tracked over time, and functional (proliferation and cytokine secretion) and phenotypic (cell surface and intranuclear) markers were assessed using flow cytometry. These were compared to CD4+ responses in 10 human leukocyte antigen-matched persons with HCV spontaneous resolution and 21 chronically infected patients treated with directly acting antiviral (DAA) therapy. Vaccination induced tetramer-positive CD4+ T cells that were highest 1-4 weeks after boosting (mean, 0.06%). Similar frequencies were obtained for those tracked following spontaneous resolution of disease (mean, 0.04%). In addition, the cell-surface phenotype (CD28, CD127) memory subset markers and intranuclear transcription factors, as well as functional capacity of peptide-specific CD4+ T-cell responses characterized after vaccination, are comparable to those following spontaneous viral resolution. In contrast, helper responses in chronic infection were infrequently detected and poorly functional and did not consistently recover following HCV cure. CONCLUSIONS: Helper CD4+ T-cell phenotype and function following HCV viral vectored vaccination resembles "protective memory" that is observed following spontaneous clearance of HCV. DAA cure does not promote resurrection of exhausted CD4+ T-cell memory in chronic infection.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/imunologia , Hepatite C Crônica/terapia , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas contra Hepatite Viral/administração & dosagem , Adenoviridae/genética , Linhagem Celular , Feminino , Vetores Genéticos/genética , Voluntários Saudáveis , Hepacivirus/isolamento & purificação , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Humanos , Imunogenicidade da Vacina , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Remissão Espontânea , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas contra Hepatite Viral/genética , Vacinas contra Hepatite Viral/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia
17.
Expert Rev Vaccines ; 19(12): 1129-1140, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33441054

RESUMO

INTRODUCTION: Hepatitis E virus (HEV) is an important cause of enterically transmitted viral hepatitis and a significant contributor to maternal mortality in endemic regions around the world, yet the global response has been limited. HEV is a disease of poverty, and the populations experiencing the greatest burden of HEV-associated illness are not benefitting from existing interventions, including WASH strategies and immunization. AREAS COVERED: Though a vaccine exists (HEV 239, Hecolin®, Xiamen Innovax Biotech, China), it is only licensed and available in the private market in China and has yet to be prequalified by the WHO for use in endemic settings and outbreaks. This review of the current state of HEV disease and subsequent recommendations for a coordinated public health response are intended to guide the global health community towards breaking the current 'vicious cycle,' in which a lack of data prevents actions that would improve health outcomes. EXPERT OPINION: Vaccine implementation in future outbreaks, targeted studies assessing vaccine effectiveness and immunogenicity in endemic regions and populations, improved understanding of the global burden, and improvements in diagnostic and epidemiologic tools are urgently needed. Strategies for implementing routine vaccination programs, improving water, sanitation, and hygiene in endemic regions.


Assuntos
Saúde Global , Hepatite E/epidemiologia , Vacinas Sintéticas/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Animais , Surtos de Doenças , Prioridades em Saúde , Hepatite E/imunologia , Hepatite E/prevenção & controle , Humanos , Imunogenicidade da Vacina , Vigilância da População , Saúde Pública , Vacinação , Vacinas Sintéticas/imunologia , Vacinas contra Hepatite Viral/imunologia
18.
J Pharm Biomed Anal ; 177: 112880, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31546137

RESUMO

Hepatitis E, which is caused by infection with hepatitis E virus (HEV), is a global health problem in both developed and developing countries. An efficacious hepatitis E vaccine was licensed (by China) in 2011 with a trade name of Hecolin®. The antigen contained in this vaccine is a truncated version of the sole capsid protein encoded by open reading frame 2, which is designated p239. In this study, the real-time and real-condition stability and accelerated stability of five lots of hepatitis E vaccine products at the end of the designated shelf life, were assessed by a well-established quality analysis platform. The protein integrity of p239 that was recovered from the vaccine lots was demonstrated using CE-SDS, LC-MS and MALDI-TOF MS. The particle characteristics of the recovered vaccine antigen were assessed by TEM and HPSEC. The immunogenicity of hepatitis E vaccines was assessed by a mouse potency assay, which is part of product release and stability testing. Several methods were employed to assess the antigenicity of vaccines with or without adjuvant dissolution. Specifically, the well-established methods of sandwich ELISA and surface plasma resonance (SPR)-based BIAcore were used with unique murine monoclonal antibodies. Most interesting, two 'dissolution-free' immunoassays were also used for in situ antigenicity assessment of the vaccines. In addition to the confirmation of vaccine stability at the end of expiry dating, i.e., after storage in recommended conditions (2-8 °C) for 36 months, the mouse potency assay and sandwich ELISA were used to assess the accelerated stability of prefilled syringes to demonstrate the feasibility of out-of-cold-chain storage. In summary, molecular and functional characterization confirmed the shelf life stability of the vaccine at the end of expiry dating and the feasibility of transporting the hepatitis E vaccine for a given period of time out of cold chains.


Assuntos
Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite E/prevenção & controle , Vacinas Sintéticas/imunologia , Vacinas contra Hepatite Viral/imunologia , Animais , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Estudos de Viabilidade , Feminino , Anticorpos Anti-Hepatite/imunologia , Antígenos de Hepatite/imunologia , Hepatite E/virologia , Humanos , Imunoensaio/métodos , Imunogenicidade da Vacina , Camundongos , Modelos Animais , Temperatura , Fatores de Tempo , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/química , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/química
19.
J Am Psychiatr Nurses Assoc ; 26(2): 172-180, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30866701

RESUMO

Background: Adults who suffer with severe and persistent mental illness (SPMI) rarely access medical care to receive preventive vaccines. Aims: To increase the rate of vaccines among the SPMI population in an outpatient community mental health center (CMHC). Methods: A review of the literature identified a gap between the general population and SPMI clients in receiving preventive vaccinations. An initial mixed-method convenience survey of SPMI clients (n = 392) provided information on current vaccination status, demographics, beliefs, and interest in receiving vaccines. A vaccination program was developed to address identified barriers and increase vaccination rates. Postintervention data were collected through a mixed-method convenience survey of SPMI clients (n = 60) who participated in immunizations clinics to evaluate client satisfaction. A partnership between the health department and CMHC was developed to deliver vaccines in a nontraditional site. Vaccines administered included annual influenza; hepatitis A; hepatitis B; herpes zoster; measles, mumps, and rubella; pneumococcal; and tetanus, diphtheria, and pertussis (Tdap). Results: More than 1,000 vaccines were administered in the first 8 months, with a significant increase in vaccination rates over baseline for individual vaccines ranging from 18.75% to 83%. Postintervention survey results found a 95% satisfaction rate. Conclusions: Implementation of a vaccination program in a nontraditional site that facilitates access for SPMI clients can promote an overwhelming increase in the vaccination rates for this underserved population. Results suggest that the integration of mental health and CMHC services can have a profound positive effect on SPMI population health.


Assuntos
Acessibilidade aos Serviços de Saúde , Programas de Imunização/estatística & dados numéricos , Pessoas Mentalmente Doentes/estatística & dados numéricos , Melhoria de Qualidade , Vacinação/estatística & dados numéricos , Adulto , Humanos , Vacinas contra Influenza/administração & dosagem , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem , Pessoas Mentalmente Doentes/psicologia , Pacientes Ambulatoriais , Satisfação do Paciente/estatística & dados numéricos , Vacinas Pneumocócicas/administração & dosagem , Saúde Pública , Vacinas contra Hepatite Viral/administração & dosagem
20.
Curr Opin Infect Dis ; 33(1): 1-9, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31789696

RESUMO

PURPOSE OF REVIEW: The WHO has set ambitious targets for hepatitis C virus (HCV) elimination by 2030. In this review, we explore the possibility of HCV micro-elimination in HIV-positive (+) MSM, discussing strategies for reducing acute HCV incidence and the likely interventions required to meet these targets. RECENT FINDINGS: With wider availability of directly acting antivirals (DAAs) in recent years, reductions in acute HCV incidence have been reported in some cohorts of HIV+ MSM. Recent evidence demonstrates that treatment in early infection is well tolerated, cost effective and may reduce the risk of onward transmission. Modelling studies suggest that to reduce incidence, a combination approach including behavioural interventions and access to early treatment, targeting both HIV+ and negative high-risk groups, will be required. HCV vaccine trials have not yet demonstrated efficacy in human studies, however phase one and two studies are ongoing. SUMMARY: Some progress towards the WHO HCV elimination targets has been reported. Achieving sustained HCV elimination is likely to require a combination approach including early access to DAAs in acute infection and reinfection, validated and reproducible behavioural interventions and an efficacious HCV vaccine.


Assuntos
Coinfecção/prevenção & controle , Erradicação de Doenças , Infecções por HIV/prevenção & controle , Hepatite C/prevenção & controle , Doença Aguda , Antivirais/uso terapêutico , Coinfecção/diagnóstico , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Homossexualidade Masculina , Humanos , Incidência , Masculino , Fatores de Risco , Comportamento de Redução do Risco , Minorias Sexuais e de Gênero , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/imunologia
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