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1.
Front Med (Lausanne) ; 10: 1125139, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37877022

RESUMO

Background: Hepatitis B virus (HBV)/Hepatitis D Virus (HDV) co-infection increases the risk of severe liver disease compared to HBV mono-infection. Adaptive immune responses to HDV are weakly detectable, and the involvement of innate immunity in the progression of HDV-related liver fibrosis is suggested. We hypothesize that an overall innate immune activation in HBV/HDV co-infection plays a role in liver disease progression and also impacts virus specific T cell response. Methods: Sixteen HBV/HDV-co-infected-patients (median age 42y/7F/6 Asian/4 White/6 Black/15 HBeAg-) and 8 HBV monoinfected-patients (median age 39y/4F/4 Asian/3 Black/1 White/HBeAg-) with median follow-up of 5 years were enrolled. Liver fibrosis was assessed by liver stiffness measurement (LSM, FibroScan®). Proliferation of CD3 + CD4+ T cells in response to viral antigens using CFSE assays and cytokine secreting monocytes was analyzed by flow cytometry. Results: Of 16 HBV/HDV, 11 were HDV-RNA+ (HBV-DNA 0-1,040 IU/mL), 5/11 Interferon (IFN) + Nucleos/tide Analog (NA), 3/11 NA monotherapy, median ALT 77 U/L at the time of sample collection, median LSM of 9.8. In 5 HDV RNA-, median HBV DNA 65 IU/mL, 4/5 prior IFN and/or NA, ALT 31 U/L, and median LSM 8.5 kPa. In 8 HBV controls, median HBV-DNA, ALT, LSM was 69 IU/mL, 33 U/L,5 kPa, respectively. PBMC stimulation with HBV core antigen (HBcAg) and HDV antigen (HDAg) showed weaker CD3 + CD4 + T-cell proliferation in HDV-RNA+ vs. HDV RNA- and HBV-mono-infected patients (p < 0.05). In HDV-RNA+ patients, a correlation between ALT and TNF-α (r = 0.76, p = 0.008), higher IL-10 levels and increased proportion of CD14 + TNF-α+ cells were found. Conclusion: In summary, during HBV/HDV coinfection, HDV RNA+ patients had weaker HBV and HDV specific responses, associated with increased TNF-α + monocytes irrespective of IFN treatment.

2.
PLOS Glob Public Health ; 3(6): e0000434, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37368866

RESUMO

Pregnant young women who exchange sex for money or commodities are at elevated biological and social risk for HIV acquisition. PrEP serves as an effective means of HIV prevention, including during pregnancy. This study aimed to explore attitudes, experiences and challenges with PrEP to understand what motivates or limits PrEP uptake and adherence specifically during pregnancy among this population of young women. Semi-structured interviews were conducted with 23 participants, recruited from the Prevention on PrEP (POPPi) study in the Good Health for Women Project clinic in Kampala, Uganda. POPPi's inclusion criteria comprised of HIV-uninfected women, aged 15-24, who exchange sex for money or commodities. Interviews focused on experience with PrEP and pregnancy. Data were analyzed utilizing a framework analysis approach. Key themes were comprised of participant barriers to and facilitators of PrEP uptake and adherence. Reasons for PrEP initiation included desire for autonomy and agency, mistrust of partners, and social support. Participants expressed challenges with initiating or sustaining their use of PrEP, including pregnancy, PrEP access and perceived or felt stigma. During pregnancy, participants' primary motivators for altering PrEP use were either understanding of PrEP safety for their baby or changes in perceptions of their HIV risk. Many of these factors were similar across participants who had experience with pregnancy and those who did not. This study highlights the importance of addressing barriers to and facilitators of PrEP uptake and persistence, especially during pregnancy where risk is elevated, with a multi-level approach. Community-oriented education, stigma reduction activities alongside access to PrEP, can serve as means for adherence. The development of robust PrEP support services and guidelines regarding PrEP use during pregnancy among high-risk women, and strategies for their implementation, are of utmost importance for the control of HIV in key populations and the elimination of mother-to-child transmission of HIV.

3.
NPJ Vaccines ; 6(1): 9, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431890

RESUMO

Obesity and cirrhosis are associated with poor hepatitis B virus (HBV) vaccine responses, but vaccine efficacy has not been assessed in nonalcoholic fatty liver disease (NAFLD). Sixty-eight HBV-naïve adults with NAFLD were enrolled through the Canadian HBV network and completed three-dose HBV or HBV/HAV vaccine (Engerix-B®, or Twinrix®, GlaxoSmithKline). Anti-HBs titers were measured at 1-3 months post third dose. In 31/68 subjects enrolled at the coordinating-site, T-cell proliferation and follicular T-helper cells (pTFH) were assessed using PBMC. Immune response was also studied in NAFLD mice. NAFLD patients were stratified as low-risk-obesity, BMI < 35 (N = 40) vs. medium-high-risk obesity, BMI > 35 (N = 28). Anti-HBs titers were lower in medium/high-risk obesity, 385 IU/L ± 79 vs. low-risk obesity class, 642 IU/L ± 68.2, p = 0.02. High-risk obesity cases, N = 14 showed lower vaccine-specific-CD3+ CD4+ T-cell response compared to low-risk obesity patients, N = 17, p = 0.02. Low vaccine responders showed dysfunctional pTFH. NAFLD mice showed lower anti-HBs levels and T-cell response vs. controls. In conclusion, we report here that obese individuals with NAFLD exhibit decreased HBV vaccine-specific immune responses.

4.
Front Microbiol ; 11: 1653, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760388

RESUMO

BACKGROUND: Chronic hepatitis B virus (HBV) infection is the leading cause of hepatocellular carcinoma (HCC) world-wide. HBV variants, particularly the G1896A pre-core (PC) and A1762T/G1764A basal core promoter (BCP) mutations, are established risk factors for cirrhosis and HCC, but the molecular biological basis is unclear. We hypothesized that these variants result in differential HBV replication, APOBEC3 family expression, and cytokine/chemokine expression. METHODS: HepG2 cells were transfected with monomeric full-length containing wild-type, PC, or BCP HBV. Cells and supernatant were collected to analyze viral infection markers (i.e., HBsAg, HBeAg, HBV DNA, and RNA). Cellular APOBEC3 expression and activity was assessed by quantitative real-time (qRT)-PCR, immunoblot, differential DNA denaturation PCR, and sequencing. Cytokine/chemokines in the supernatant and in serum from 11 CHB carriers (4 non-cirrhotic; 7 cirrhotic and/or HCC) with predominantly wild-type, PC, or BCP variants were evaluated by Luminex. RESULTS: HBeAg expression was reduced in PC and BCP variants, and higher supernatant HBV DNA and HBV RNA levels were found with A1762T/G1764A vs. G1896A mutant (p < 0.05). Increased APOBEC3G protein levels in wild-type vs. mutant were not associated with HBV covalently closed circular DNA G-to-A hypermutations. Differences in cytokine/chemokine expression in culture supernatants, especially IL-13 were observed amongst the variants analyzed. Noticeable increases of numerous cytokines/chemokines, including IL-4 and IL-8, were observed in ex vivo serum collected from CHB carriers with PC mutant. CONCLUSION: HBV sequence variation leads to differences in HBV protein production (HBeAg) and viral replication in addition to altered host innate antiviral restriction factor (APOBEC3) and cytokine/chemokine expression.

5.
Cancer Lett ; 480: 39-47, 2020 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-32229190

RESUMO

The hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC), partly driven by viral integration and specific oncogenic HBV variants. However, the biological significance of HBV genomes within lymphoid cells (i.e., peripheral blood mononuclear cells, PBMCs) is unclear. Here, we collected available plasma, PBMC, liver, and tumor from 52 chronic HBV (CHB) carriers: 32 with HCC, 19 without HCC, and one with dendritic cell sarcoma, DCS. Using highly sensitive sequencing techniques, next generation sequencing, and AluPCR, we demonstrate that viral genomes (i.e., HBV DNA, RNA, and cccDNA), oncogenic variants, and HBV-host integration are often found in all sample types collected from 52 patients (including lymphoid cells and a DCS tumor). Viral integration was recurrently identified (n = 90 such hits) in genes associated with oncogenic consequences in lymphoid and liver cells. Further, HBV genomes increased in PBMCs derived from 7 additional (treated or untreated) CHB carriers after extracellular mitogen stimulation. Our study shows novel HBV molecular data and replication not only liver, but also within 63.8% of lymphoid cells analysed (including a representative lymphoid cell malignancy), that was enhanced in ex vivo stimulated PBMC.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/complicações , Neoplasias Hepáticas/virologia , Linfócitos/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Feminino , Hepatite B Crônica/virologia , Interações Hospedeiro-Patógeno , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Vírus Oncogênicos , Polimorfismo de Nucleotídeo Único , RNA Viral/sangue , Integração Viral , Replicação Viral , Adulto Jovem
6.
Hepatol Commun ; 4(2): 157-171, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32025602

RESUMO

The hepatitis B virus (HBV) is an important human pathogen. Unvaccinated infants infected through mother-to-child transmission (MTCT) are at >95% risk of developing serum hepatitis B surface antigen-positive chronic hepatitis B (CHB). Despite complete passive-active HBV immunoprophylaxis, approximately 10% of infants born to mothers who are highly viremic develop CHB, and thus maternal treatment with nucleos(t)ide analogs (tenofovir disoproxil fumarate, lamivudine, or telbivudine) is recommended in the third trimester of pregnancy to reduce MTCT risk. Viral rebound usually occurs after stopping treatment and, in the context of maternal immunologic reconstitution postpartum, can also precipitate host immune-mediated hepatic (biochemical) flares. In this article, we review the epidemiology of HBV MTCT, discuss management and potential mechanisms of HBV vertical transmission, and highlight recent studies on virologic and immunologic aspects of hepatitis B in pregnancy and postpartum.

7.
Dig Dis Sci ; 65(1): 204-214, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31376084

RESUMO

PURPOSE: HBV precore (PC) and basal core promoter (BCP) mutants are associated with liver disease severity, yet have been suggested to protect against HBV vertical transmission. HBV within peripheral blood mononuclear cells (PBMC) has been reported in association with intrauterine HBV infection. We analyzed HBV replication status in PBMC and PC/BCP mutants in PBMC from pregnant chronic hepatitis B (CHB) patients. METHODS: Pregnant CHB carriers were assessed for HBeAg, HBV-DNA, ALT in second-third trimester and liver stiffness measurement (LSM) postpartum. HBV-DNA, HBV-cccDNA, and HBV-mRNA were tested in PBMC by in-house PCR. BCP/PC variants were determined by Sanger sequencing and analyzed using MEGA7. RESULTS: In 37 CHB pregnant carriers, median age 32 years, 53% Asian, median ALT 19 versus 26 U/L, median HBV-DNA 2.6 versus 8.1 logIU/mL (untreated vs. treated), eight HBeAg+, with genotype 10%A, 29%B, 21%C, 10%D, 19%E, eight received tenofovir in pregnancy to reduce vertical transmission risk. HBV-DNA was detected in ~ 55% (25/45) PBMC, and PC/BCP mutations were found in 36% (9/25) and 4% (1/25), respectively. All infants received HBV immunoprophylaxis and tested HBV surface antigen negative at 9-12 months of age. During a median 4 years (IQR 3-5), follow-up all mothers showed normal LSM, with no significant change in ALT, HBeAg status, or HBV-DNA levels compared to baseline in untreated CHB carriers. CONCLUSION: In this multiethnic cohort of pregnant CHB carriers, HBV replicative intermediates and PC/BCP mutants were found in significant proportion of PBMC, but were not associated with increased risk of HBV immunoprophylaxis failure or liver disease severity over long-term follow-up.


Assuntos
DNA Viral/genética , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Leucócitos Mononucleares/virologia , Mutação , Complicações Infecciosas na Gravidez/virologia , Regiões Promotoras Genéticas , Adulto , Antivirais/uso terapêutico , Feminino , Seguimentos , Genótipo , Vacinas contra Hepatite B/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/transmissão , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Cirrose Hepática/diagnóstico , Cirrose Hepática/prevenção & controle , Cirrose Hepática/virologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Carga Viral , Replicação Viral
8.
J Pediatr Gastroenterol Nutr ; 68(2): 182-189, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30640271

RESUMO

OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is common; however, no information is available on how pediatric gastroenterologists in the United States manage NAFLD. Therefore, study objectives were to understand how pediatric gastroenterologists in the US approach the management of NAFLD, and to identify barriers to care for children with NAFLD. METHODS: We performed structured one-on-one interviews to ascertain each individual pediatric gastroenterologist's approach to the management of NAFLD in children. Responses were recorded from open-ended questions regarding screening for comorbidities, recommendations regarding nutrition, physical activity, medications, and perceived barriers to care. RESULTS: Response rate was 72.0% (486/675). Mean number of patients examined per week was 3 (standard deviation [SD] 3.5). Dietary intervention was recommended by 98.4% of pediatric gastroenterologists. Notably, 18 different dietary recommendations were reported. A majority of physicians provided targets for exercise frequency (72.6%, mean 5.6 days/wk, SD 1.6) and duration (69.9%, mean 40.2 minutes/session, SD 16.4). Medications were prescribed by 50.6%. Almost one-half of physicians (47.5%) screened for type 2 diabetes, dyslipidemia, and hypertension. Providers who spent more than 25 minutes at the initial visit were more likely to screen for comorbidities (P = 0.003). Barriers to care were reported by 92.8% with 29.0% reporting ≥3 barriers. CONCLUSIONS: The majority of US pediatric gastroenterologists regularly encounter children with NAFLD. Varied recommendations regarding diet and exercise highlight the need for prospective clinical trials. NAFLD requires a multidimensional approach with adequate resources in the home, community, and clinical setting.


Assuntos
Gastroenterologistas/estatística & dados numéricos , Gastroenterologia/métodos , Hepatopatia Gordurosa não Alcoólica , Pediatria/métodos , Padrões de Prática Médica/estatística & dados numéricos , Criança , Feminino , Humanos , Masculino , Estados Unidos
9.
J Clin Virol ; 111: 42-47, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30639847

RESUMO

BACKGROUND: Hepatitis B virus (HBV) flares have been reported due to alterations in the immune system during pregnancy. Recent studies in non-pregnant chronic hepatitis B (CHB) carriers have indicated that serum HBV RNA is a novel viral marker to assess treatment response and risk of disease flares. OBJECTIVES: To analyze serum HBV RNA levels in association with established HBV markers in pregnant and/or post-partum CHB carriers. STUDY DESIGN: In this prospective cohort study, serum and plasma were collected from 46 pregnant and/or post-partum CHB patients. Clinical data included demographics, hepatitis B e antigen (HBeAg) status (Abbott), quantitative hepatitis B s antigen (qHBsAg) levels (Abbott), HBV DNA (Abbott, sensitivity 10 IU/mL), alanine aminotransferase (ALT), liver stiffness measurement (LSM, post-partum), and treatment regime. Serum HBV total RNA and pre-genomic (pg)RNA were quantified using in-house assays, and HBV genotype was determined by direct population sequencing of HBV surface gene. Parametric and non-parametric statistical methods were used for analysis. RESULTS: In this study, we found that serum HBV total RNA levels correlated with the HBeAg status, HBV DNA, qHBsAg, ALT, and LSM while serum HBV pgRNA levels did not (p < 0.05, N = 46). Additionally, HBV total RNA & pgRNA levels increased, HBV DNA levels decreased, and qHBsAg levels remained unchanged throughout tenofovir disoproxil fumarate (TDF) treatment (N = 2). CONCLUSIONS: The associations between serum HBV total RNA with other validated markers indicates it may be a complementary HBV marker to monitor liver disease and HBV replication during pregnancy.


Assuntos
Vírus da Hepatite B/isolamento & purificação , RNA Viral/sangue , Carga Viral , Adulto , Biomarcadores/sangue , DNA Viral/sangue , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/virologia , Humanos , Gravidez , Estudos Prospectivos , RNA/sangue , Adulto Jovem
10.
Biotechnol Genet Eng Rev ; 34(1): 139-151, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29785877

RESUMO

The hepatitis B virus (HBV) is predominantly a hepatotropic virus but also infects cells of the lymphatic system. HBV genomes (DNA, messenger (m)RNA, covalently closed circular (ccc) DNA) and proteins have been found in extrahepatic sites such as peripheral blood mononuclear cells (PBMC), lymph nodes, spleen, bone marrow and cerebrospinal fluid. HBV entry into hepatocytes occurs by binding of the HBV preS1 surface protein to its specific receptor, the bile acid transporter, sodium taurocholate co-transporting polypeptide (NTCP). Although the mechanism of HBV entry into lymphatic cells is unknown, the pre S1 encoded surface protein is thought to be involved. Extrahepatic HBV infection has been studied in both chronic HBV (CHB) and in occult HBV infection (OBI). Studies have shown that HBV genomes are present in different PBMC subsets from chronically infected carriers. Unique HBV variants have been found in PBMC compared to plasma or liver in both nucleos(t)ide analogue (NA) treated and untreated CHB carriers, suggesting replication and compartment specific evolution of HBV. In HBV coinfection, HBV genomes were found in PBMC from hepatitis C virus (HCV), human immunodeficiency virus (HIV) and hepatitis delta virus (HDV) co-infected individuals. Moreover, during pregnancy, the trans placental passage of HBV infected PBMC from highly viremic mothers to infants is one of the postulated means of vertical transmission of HBV. Taken together, HBV infection in extrahepatic sites (i.e., PBMC) is implicated in multiple facets of HBV pathogenesis such as persistence, viral evolution and vertical transmission.


Assuntos
Vírus da Hepatite B/fisiologia , Hepatite B/transmissão , Sistema Linfático/virologia , Feminino , Genoma Viral , Hepatite B/virologia , Vírus da Hepatite B/genética , Humanos , Transmissão Vertical de Doenças Infecciosas , Tropismo Viral , Internalização do Vírus
11.
Virol J ; 14(1): 203, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29065883

RESUMO

BACKGROUND: The pathogenesis of acute-on-chronic liver failure (ACLF) in chronic hepatitis B (CHB) is not well understood. The aim of this study was to investigate whether there is an association between HBV polymerase (P)/overlapping surface (S) gene and basal core promoter (BCP)/precore (PC) variants and development of ACLF in CHB. METHODS: Two CHB patient cohorts were compared: (i) ACLF (N = 12) (11/12 M, median age 52 yrs., 5/9 genotype C, 6/12 HBeAg+), (ii) 27 treatment native CHB carriers (15/27 M, median age 44 yrs., 9 genotype B, 10 genotype C, 1 genotype A, 5 genotype D, 2 genotype E). Clonal sequencing of PCR-amplified HBV P/S and BCP/PC gene fragments was done and HBV diversity, frequency of immune escape (IE) and drug resistance (DR) mutations and mutations in BCP/PC gene (G1896A and A1762T/G1764A), were compared between each group. RESULTS: Our data showed the incidence of IE and clusters of mutations in the HBV S region was significantly greater in ACLF patients vs. treatment naïve CHB patients (p < 0.05). Additionally, a significantly higher frequency of G1896A and A1762T/G1764A mutations were found in HBeAg negative than in ACLF patients (p < 0.0001). CONCLUSION: In our study, ACLF was not associated with a specific genomic mutation. However, higher frequency of IE mutations along with various mutations clustering in the HBV S region could contribute to or be an outcome of ACLF in CHB infection. (words 226).


Assuntos
Portador Sadio , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/complicações , Hepatite B Crônica/virologia , Falência Hepática/etiologia , Mutação , Adulto , Alelos , DNA Viral , Farmacorresistência Viral , Feminino , Genoma Viral , Genótipo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Humanos , Falência Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Carga Viral , Adulto Jovem
12.
Am J Reprod Immunol ; 78(4)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28544232

RESUMO

PROBLEM: In chronic hepatitis B (CHB) carriers, alanine transaminase (ALT) flares are common in the peripartum period. There are limited data on immunological changes of pregnancy in CHB. We hypothesize that in pregnant CHB carriers, the Th1/Th2 cytokine ratio is altered resulting in changes in biochemical/virological and liver fibrosis markers. STUDY METHODS: Serum from 38 pregnant/post-partum CHB carriers (median age 32 years, 53% Asian, 8 HBeAg+ ) was tested for HBV DNA, quantitative HBV surface antigen, ALT and liver fibrosis by transient elastography (TE). Serum cytokines were analyzed using a Luminex assay. RESULTS: Untreated CHB cases had mild ALT flares post-partum, but showed normal TE, and no change in viral markers despite increased Th1 cytokines compared to healthy controls (P<.05). CONCLUSION: CHB carriers show increased Th1 cytokines in the peripartum period albeit with no effect on viral load or liver disease suggesting an aborted antiviral immune response.


Assuntos
Etnicidade , Vírus da Hepatite B/fisiologia , Hepatite Crônica/epidemiologia , Hepatopatias/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Alanina Transaminase/sangue , Portador Sadio , Estudos de Coortes , Citocinas/metabolismo , Feminino , Humanos , Evasão da Resposta Imune , Imunidade , Período Periparto , Gravidez , Risco , Células Th1/imunologia , Carga Viral
13.
Viral Immunol ; 29(6): 350-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27285290

RESUMO

In the developing countries, Hepatitis E virus (HEV) is a predominant cause of sporadic acute hepatitis in adults and waterborne epidemics leading to high mortality in pregnant women. Vaccine development mainly focuses on the structural capsid protein open-reading-frame-2 (ORF-2) of the virus. We successfully evaluated liposome-adjuvanted recombinant neutralizing epitope protein (rNEp), a part of ORF-2, 458-607aa, in mice and rhesus macaques. We compared immune response to adjuvants alone, rNEp alone, or adjuvanted with liposome (lipo-rNEp)/alum (al-rNEp) in mice following intramuscular administration of two doses of 5 µg each. IgG anti-HEV titers (enzyme-linked immunosorbent assay), immunophenotyping (flow cytometry, CD3(+)CD4(+), CD3(+)CD8(+), CD11c(+), CD11b(+), CD19(+) cells; costimulatory markers CD80, CD86, MHC-I, MHC-II, and early activation marker CD69), and levels of Th1/Th2 cytokines (IL-2/IFN-γ/IL-4/IL-5 and additionally IL-1ß/IL-6/IL-10/TNF for early time points) were determined at early (4/12/24-h postdose-1) and later time points (2 weeks post-both doses). IgG anti-HEV titers were higher in the lipo-rNEp group than al-rNEp post-both doses (p < 0.05). At early time points, cell type proportions were comparable at the site of injection; IL-Iß levels increased in lipo-rNEp, 24 h, while IL-6 levels rose in lipo-rNEp/al-rNEp/alum-alone groups, 4 h, compared to controls. In the draining lymph nodes (DLNs), CD11c(+)CD86(+) cells increased at 24 h in liposome-alone/lipo-rNEp groups. A rise in the CD11c(+)CD69(+) cells was noted in the lipo-rNEp group compared to other groups (p < 0.05). Cytokine levels in the spleen/sera remained unchanged in all the groups (p > 0.05). At 2 weeks postdose-2, CD11c(+)MHC-II(+)/CD11b(+)MHC-II(+) cells increased in the spleen in the lipo-rNEp and al-rNEp groups, respectively. In the DLNs, CD19(+)MHC-II(+) cells increased in rNEp/al-rNEp/lipo-rNEp groups post-both doses and CD11c(+)CD86(+) cells in the lipo-rNEp group. A balanced Th1/Th2 response was evident in the lipo-rNEp, while a Th2 bias was noted in al-rNEp. Different immune response gene clustering patterns were noted in uncultured spleens from immunized mice and cultured-stimulated splenocytes. In conclusion, lipo-rNEp is a better immunogen, works through dendritic cells, and elicits a balanced Th1/Th2 response, while alum functions through macrophages and induces a Th2 response.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Compostos de Alúmen/administração & dosagem , Epitopos/imunologia , Hepatite E/prevenção & controle , Lipossomos/administração & dosagem , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Animais , Citocinas/análise , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Feminino , Anticorpos Anti-Hepatite/sangue , Hepatite E/imunologia , Esquemas de Imunização , Imunoglobulina G/sangue , Imunofenotipagem , Injeções Intramusculares , Macaca mulatta , Camundongos Endogâmicos BALB C , Subpopulações de Linfócitos T/química , Subpopulações de Linfócitos T/imunologia , Fatores de Tempo , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas Virais/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
14.
Virol J ; 12: 70, 2015 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-25935713

RESUMO

BACKGROUND: Pregnant women from developing countries are at high-risk of hepatitis E-associated high mortality and constitute priority population for vaccination. So far, candidate vaccines have not been evaluated during pregnancy. We evaluated our vaccine candidate, recombinant Neutralizing Epitope protein (rNEp) encapsulated in liposomes, in pregnant mice. METHODS: A single dose (10 µg) of the formulation was administered intramuscularly on day 7 of pregnancy. Titres of serum IgG antibodies to hepatitis E virus (IgG-anti-HEV), levels of cytokines and biochemical parameters were determined. Spleens were harvested from pregnant and non-pregnant mice for immunophenotyping (flow cytometry), cytokines (cytometric bead array, CBA) and gene expression of immune response genes (Taqman low density array, TLDA). Histopathology studies of spleen, liver, kidneys, brain and muscle was carried out. RESULTS: The vaccine was well-tolerated during pregnancy as evidenced by histopathology and serum biochemical parameters. Anti-HEV titres were significantly higher in the pregnant balb/c and C57BL/6 mice (3592 ± 802 and 1016 ± 138 respectively, than in non-pregnant groups (634 ± 191 and 320 ± 55 respectively, p < 0.001 for both) suggesting that the higher antibody response in pregnant mice was independent of the genetic makeup of the host but immunogen-driven. Pups receiving vertically transferred antibodies developed lower anti-HEV antibodies (p < 0.05) when immunized with the formulation after seronegativity than in the age-matched mice without such antibodies. In non-pregnant mice, a Th1 response and discordance between splenic and serum cytokines was evident while in pregnancy, a Th2 bias was observed irrespective of immunization. Increased CD19 levels correlated with higher anti-HEV titres in pregnant mice. CONCLUSION: The single dose of the vaccine was safe and highly immunogenic in pregnant mice. Degree and type of immune response to vaccination during pregnancy is immunogen-driven. In-depth studies are needed to understand the underlying immunologic mechanism(s). These encouraging results for a vaccine intended for use in pregnant women should be confirmed in higher animals.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Anticorpos Neutralizantes/sangue , Epitopos de Linfócito B/imunologia , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Lipossomos/administração & dosagem , Vacinas contra Hepatite Viral/imunologia , Estruturas Animais/patologia , Animais , Citocinas/metabolismo , Feminino , Perfilação da Expressão Gênica , Imunoglobulina G/sangue , Imunofenotipagem , Injeções Intramusculares , Leucócitos Mononucleares/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Gravidez , Baço/imunologia , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/efeitos adversos
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