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1.
J Med Virol ; 95(1): e28125, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36064856

RESUMO

Maternal hepatitis B e Antigen (HBeAg) positivity poses a risk for hepatitis B virus (HBV) mother-to-child transmission (MTCT). In resource-constrained settings, HBeAg testing is recommended as an alternative to HBV DNA testing to establish antiviral prophylaxis eligibility. Nevertheless, the high prevalence of HBeAg-negative chronic hepatitis B (e-CHB) in many countries should not be overlooked. We studied HBV characteristics and explored the potential MTCT risk among HBeAg-negative/HBsAg-positive expectant mothers in an area prevalent of e-CHB. Among 1348 pregnant mothers screened for HBV infection, 81 (6.0%) were HBsAg-positive. These women were examined for HBeAg, HBV DNA, and cord blood HBV DNA. Sixteen (19.8%) of the HBsAg-positive mothers were HBeAg-positive, whereas 65 (80.2%) were HBeAg-negative, including eight inactive carriers (HBsAg <100 IU/ml, HBV DNA ≤ 2000 IU/ml, and ALT < 40 IU/L). Of the remaining 57 HBeAg-negative mothers, ten revealed HBV Basal Core Promoter or Precore mutations, with three having high viremia (HBV DNA > 200 000 IU/mL), which is associated with a high MTCT risk and therefore qualifies them for antiviral prophylaxis. This pilot study provides a cautionary note to the interpretation of negative HBeAg test results when determining eligibility for MTCT antiviral prophylaxis in situations with limited resources and in regions where e-CHB is prevalent.


Assuntos
Hepatite B Crônica , Hepatite B , Complicações Infecciosas na Gravidez , Feminino , Gravidez , Humanos , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/epidemiologia , Antígenos E da Hepatite B , Antígenos de Superfície da Hepatite B , Gestantes , DNA Viral , Projetos Piloto , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Vírus da Hepatite B/genética , Antivirais/uso terapêutico , Hepatite B/tratamento farmacológico
2.
BMC Infect Dis ; 18(1): 279, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29914398

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection is a world health problem with an estimated 257 million chronically infected people. Indonesia, with 7.1% prevalence of hepatitis B surface antigen (HBsAg), is classified as a moderately endemic country. Healthcare workers (HCWs) are at high occupational risk for HBV infection and potentially becoming transmitters for further infections. In Indonesia, the extent of hepatitis B among HCWs and specific control strategy are not available. This study evaluated the seroprevalence of HBV infection and associated risk factors in HCWs from four areas in South Sulawesi, Indonesia. METHODS: A total of 467 HCWs (median age 28 years, male/female 89/378) were recruited. All HCWs were classified into three age groups (< 20-29, 30-39, and ≥ 40 years old), three work types (administration, non-intervention, and intervention), and three service periods (< 5, 5-9, and ≥ 10 years). Data on socio-demographic characteristics and risk factors were obtained by questionnaire and serum samples were tested for HBV markers (HBsAg, its antibody [anti-HBs], and antibody to core antigen [anti-HBc]. Chi-square or Fisher's exact test was used to determine differences in categorical variables, while risk factors were reported as odds ratios (OR). RESULTS: The prevalence of current HBV infection (HBsAg+), exposure to HBV (anti-HBc+), and immunity to HBV (anti-HBs+) was 6.2, 19.2, and 26.1%, respectively. Two thirds (66.17%) of all HCWs did not express any of HBV markers. In relation to the age groups, intervention work-type, and service period of HCWs, increasing trends were observed in the exposure to HBV (p < 0.001, p < 0.001, and p < 0.010, respectively) and the immunity to HBV by natural infection (HBsAg-, anti-HBc+, anti-HBs+) (p = 0.004, p < 0.001, and p < 0.010, respectively). Needlestick injury contributed the highest risk factor (OR = 1.71; 95% CI: 1.05-2.77; p = 0.029) for infection acquisition, which mostly occurred in the intervention group (p = 0.046). CONCLUSION: Exposure to HBV showed significant association with HCWs' age, work type, and service period. Needlestick injury was the highest risk factor for the acquisition of HBV, with highest events in the intervention work-type. Two thirds of HCWs were still susceptible to HBV infection. Intervention strategies at the national level are required to mount prevention, control, and management of HBV infection in HCWs.


Assuntos
Pessoal de Saúde/estatística & dados numéricos , Hepatite B/epidemiologia , Adolescente , Adulto , Feminino , Hepatite B/diagnóstico , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Humanos , Indonésia/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Inquéritos e Questionários
3.
Virol J ; 7: 326, 2010 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-21087462

RESUMO

BACKGROUND: Selection of hepatitis B virus (HBV) by host immunity has been suggested to give rise to variants with amino acid substitutions at or around the 'a' determinant of the surface antigen (HBsAg), the main target of antibody neutralization and diagnostic assays. However, there have never been successful attempts to provide evidence for this hypothesis, partly because the 3 D structure of HBsAg molecules has not been determined. Tertiary structure prediction of HBsAg solely from its primary amino acid sequence may reveal the molecular energetic of the mutated proteins. We carried out this preliminary study to analyze the predicted HBsAg conformation changes of HBV variants isolated from Indonesian blood donors undetectable by HBsAg assays and its significance, compared to other previously-reported variants that were associated with diagnostic failure. RESULTS: Three HBV variants (T123A, M133L and T143M) and a wild type sequence were analyzed together with frequently emerged variants T123N, M133I, M133T, M133V, and T143L. Based on the Jameson-Wolf algorithm for calculating antigenic index, the first two amino acid substitutions resulted in slight changes in the antigenicity of the 'a' determinant, while all four of the comparative variants showed relatively more significant changes. In the pattern T143M, changes in antigenic index were more significant, both in its coverage and magnitude, even when compared to variant T143L. These data were also partially supported by the tertiary structure prediction, in which the pattern T143M showed larger shift in the HBsAg second loop structure compared to the others. CONCLUSIONS: Single amino acid substitutions within or near the 'a' determinant of HBsAg may alter antigenicity properties of variant HBsAg, which can be shown by both its antigenic index and predicted 3 D conformation. Findings in this study emphasize the significance of variant T143M, the prevalent isolate with highest degree of antigenicity changes found in Indonesian blood donors. This highlights the importance of evaluating the effects of protein structure alterations on the sensitivity of screening methods being used in detection of ongoing HBV infection, as well as the use of vaccines and immunoglobulin therapy in contributing to the selection of HBV variants.


Assuntos
Antígenos de Superfície da Hepatite B/química , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/química , Vírus da Hepatite B/genética , Mutação de Sentido Incorreto , Mutação Puntual , Anticorpos Neutralizantes/imunologia , Doadores de Sangue , DNA Viral/química , DNA Viral/genética , Anticorpos Anti-Hepatite/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Indonésia , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Estrutura Terciária de Proteína , Análise de Sequência de DNA
4.
Sci Rep ; 9(1): 4026, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858465

RESUMO

Hyaluronic acid (HA) is a glycosaminoglycan of extracellular matrix related to cell surface which interacts with various cell types. To understand the role of HA during hepatocarcinogenesis, we assessed the effect of the inhibition of HA deposition and its association with heterogeneous hepatocellular carcinoma (HCC) cells. In this study, we used transgenic mice C57BL/6J-Tg(Alb1HBV)44Bri/J (HBV-TG) and normal C57BL/6 J (WT) for in vivo study, while HCC cells Huh7 and JHH6 as in vitro models. Both models were treated with an HA inhibitor 4-methylumbelliferone (4MU). We observed that 4MU treatments in animal model down-regulated the mRNA expressions of HA-related genes Has3 and Hyal2 only in HBV-TG but not in normal WT. As observed in vivo, in HCC cell lines, the HAS2 mRNA expression was down-regulated in Huh7 while HAS3 in JHH6, both with or without the presence of extrinsic HA. Interestingly, in both models, the expressions of various cancer stem cells (CD44, CD90, CD133, and EpCAM) were also decreased. Further, histological analysis showed that 4MU treatment with dose 25 mg/kg/day reduced fibrosis, inflammation, and steatosis in vivo, in addition to be pro-apoptotic. We concluded that the inhibition of HA reduced the expressions of HA-related genes and stem cells markers in both models, indicating a possible modulation of cells-to-cells and cells-to-matrix interaction.


Assuntos
Carcinogênese , Carcinoma Hepatocelular/metabolismo , Ácido Hialurônico/antagonistas & inibidores , Himecromona/farmacologia , Neoplasias Hepáticas Experimentais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neoplásicas/patologia
5.
Sci Rep ; 8(1): 13168, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-30177788

RESUMO

Chronic infection of Hepatitis B Virus (HBV) is one of the highest risk factors of hepatocellular carcinoma (HCC). The accumulation of HBV surface antigen (HBsAg) into hepatocytes induces inflammation and oxidative stress, impairing their replicative ability and allowing the activation of the hepatic stem cells (SC) compartment. This study aimed to understand the involvement of SC during hepatocarcinogenesis in HBsAg-related liver damage, from early injury until HCC. HBsAg-transgenic (TG) and wild type (WT) mouse were followed at several stages of the liver damage: inflammation, early hepatocytes damage, dysplasia, and HCC. Serum transaminases, liver histology, and diagnostic data were collected. The expressions of SC and cancer stem cells (CSC) markers was analyzed by RT-qPCR, immunohistochemistry and Western blot. Starting from 3 months, TG animals showed a progressive liver damage characterized by transaminases increase. The up-regulations of SCs markers Cd34 and Sca-1 started from the beginning of the inflammatory stage while progressive increase of Krt19 and Sox9 and CSCs markers Epcam and Cd133 from early hepatic injury. The expressions of Cd133, Cd34, and Afp were significantly higher in HCC compared to paired non-HCC tissue, in contrast to Epcam and Krt19. Western blot and IHC confirmed the positivity of Cd34 and Cd133 in small cells subpopulation.


Assuntos
Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Antígenos de Superfície da Hepatite B/genética , Hepatócitos/metabolismo , Neoplasias Hepáticas/genética , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133/genética , Antígeno AC133/metabolismo , Animais , Antígenos CD34/genética , Antígenos CD34/metabolismo , Antígenos Ly/genética , Antígenos Ly/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Expressão Gênica , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/genética , Hepatite B Crônica/metabolismo , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Hepatócitos/patologia , Humanos , Queratina-19/genética , Queratina-19/metabolismo , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/patologia , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Células-Tronco/metabolismo , Células-Tronco/patologia , Transaminases/sangue , Transaminases/genética
6.
Hepatol Int ; 11(1): 96-104, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27624502

RESUMO

BACKGROUND: HBV-infected patients are potential sources of intra-familial transmission. We studied HBV transmission and molecular characteristics within families of HBV-related chronic liver disease (CLD) patients. METHODS: Family members [index cases (ICs), spouses, and 1-18-year-old children] of HBV-related CLD patients were tested for HBsAg, anti-HBc, and anti-HBs. HBsAg-positive subjects were tested for HBeAg/anti-HBe. Anti-HBc-positive children together with their family members were further investigated for HBV DNA. Sequences of positive isolates were analyzed over surface, precore (PC) and basal core promoter (BCP) regions. RESULTS: Among 94 children of 46 ICs, the prevalence of HBsAg, anti-HBc, and anti-HBs was 10 (10.6 %), 19 (20.2 %), and 46 (48.9 %), respectively. Thirty-eight (40.4 %) children were seronegative, indicating susceptibility to HBV infection. HBV DNA was identified in all ICs, 4 spouses, and 16 children. Having both parents with HBsAg positive and at least two HBV carriers in the households were significant risk factors of intra-familial transmission. HBV genotype/subtype distributions were comparable between children and ICs/spouses, with predominance of genotype B. The majority of HBV DNA sequences found in children were identical to their corresponding ICs-particularly mothers-including mutation patterns in the surface, PC, and BCP regions. Recognized mutations associated with HBsAg detection and/or vaccination failure, T140I, T143S/M, G145R, and Y161F, were identified in 20 subjects; while mutations linked to HBeAg-defective variants, PC G1896A and BCP A1762T/G1764A, were found in 7 and 11 subjects, respectively. CONCLUSIONS: Children of HBV-related CLD patients were at increased risk of HBV infection through multi-modal transmission routes despite negative parental HBsAg and HBeAg status.


Assuntos
Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/transmissão , Adolescente , Portador Sadio/virologia , Criança , Pré-Escolar , Estudos Transversais , DNA Viral/genética , Feminino , Genótipo , Anticorpos Anti-Hepatite B/imunologia , Antígenos da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Humanos , Masculino , Mutação , Prevalência
7.
World J Gastroenterol ; 22(4): 1497-512, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26819517

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Chronic infection of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) is a major risk factor in the development of the HCC, independently from excessive alcohol abuse and metabolic disease. Since the biology of HBV and HCV is different, their oncogenic effect may go through different mechanisms, direct and/or indirect. Viral hepatitis infection is associated with cellular inflammation, oxidative stress, and DNA damage, that may lead to subsequent hepatic injuries such as chronic hepatitis, fibrosis, cirrhosis, and finally HCC. Direct oncogenic properties of these viruses are related with their genotypic characteristics and the ability of viral proteins to interact with host proteins, thus altering the molecular pathways balance of the cells. In addition, the integration of HBV DNA, especially the gene S and X, in a particular site of the host genome can disrupt chromosomal stability and may activate various oncogenic mechanisms, including those in hematopoietic cells. Recently, several studies also had demonstrated that viral hepatitis could trigger the population of hepatic cancer stem cells. This review summarize available pre-clinical and clinical data in literature regarding oncogenic properties of HBV and HCV in the early initiation of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Transformação Celular Viral , Hepacivirus/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Hepatite C Crônica/virologia , Neoplasias Hepáticas/genética , Oncogenes , Animais , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Genótipo , Hepacivirus/patogenicidade , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Interações Hospedeiro-Patógeno , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/virologia , Fatores de Risco
8.
Int J Infect Dis ; 41: 83-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26571304

RESUMO

BACKGROUND: New cases of hepatitis B virus (HBV) infection continue to occur worldwide. Most of these are due to mother-to-child transmission (MTCT), with maternal viraemia as the most important contributing factor. The hepatitis B surface antigen (HBsAg) level, which correlates positively with viral load, has been used for treatment monitoring in chronic hepatitis B. This study evaluated the usefulness of quantitative HBsAg for viral load prediction in HBsAg-positive pregnant women. METHODS: A total of 943 pregnant women in Makassar, Indonesia, were screened for HBsAg. Sixty-four women were HBsAg-positive and investigated. HBsAg level and hepatitis B e antigen (HBeAg)/hepatitis B e antibody (anti-HBe) status were determined serologically. Viral load was measured by real-time PCR. HBV DNA was sequenced and analysed for identification of genotype and basal core promoter (BCP)/precore (PC) mutations. RESULTS: Of 64 subjects, 12 (18.8%) were HBeAg-positive and 52 (81.3%) were HBeAg-negative. HBsAg and HBV DNA levels were significantly higher in the HBeAg-positive group (p<0.001). HBsAg and HBV DNA levels were positively correlated in the HBeAg-positive group (r = 0.659; p=0.02), but not in the HBeAg-negative group (r=0.194; p=0.168). Low HBsAg levels (<3.0 log10 IU/ml) corresponded with HBV DNA levels<6.0 log10 IU/ml (r=0.404; p=0.001), a recognized threshold for MTCT. Genotype C was more prevalent than genotype B, but not associated with HBsAg level, viral load, or HBeAg status. Two-thirds of HBeAg-negative subjects with high HBV DNA levels harboured BCP (A1762T/G1764A) and/or PC (G1896A) variants. CONCLUSIONS: HBsAg levels provide a good viral load predictor in HBeAg-positive but not HBeAg-negative pregnant women. The HBeAg-negative group had a frequent occurrence of BCP/PC variants, which may have contributed to the lack of correlation observed. Samples with a low HBsAg level, which is associated with a low risk of MTCT, do not require HBV DNA measurement.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/virologia , Complicações Infecciosas na Gravidez/virologia , Carga Viral , Adulto , Sequência de Bases , DNA Viral/genética , Feminino , Genótipo , Anticorpos Anti-Hepatite B/imunologia , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Hepatite B Crônica/epidemiologia , Humanos , Indonésia/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Mutação , Gravidez , Prevalência , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Testes Sorológicos , Viremia/imunologia , Adulto Jovem
9.
Hepatol Int ; 4(3): 608-14, 2010 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-21063484

RESUMO

BACKGROUND AND AIMS: Occult hepatitis B virus infection (OBI) poses a challenge to the safety of blood donation. The prevalence of OBI is not well documented in Indonesia, although this information in such an endemic country is needed. This study was aimed to evaluate the prevalence of occult hepatitis B in blood donors from two cities of Indonesia, and to study the genetic variation and its effect on the predicted antigenicity of HBsAg. METHODS: Serum samples of 309 regular blood donors negative for HBsAg were tested for anti-HBs and anti-HBc. Hepatitis B virus (HBV) DNA isolated from anti-HBc-positive samples were analyzed by polymerase chain reaction, cloned and sequenced. Antigenic properties of identified HBsAg mutants were predicted by calculation of the antigenic index. RESULTS: Of the 309 HBsAg-negative samples, anti-HBc was positive in 134 (43.4%) and HBV DNA was detected in 25 (8.1%). Seven of the viremic samples had nucleotide substitutions (A521G, A551T, C582T, and A562G) in the S gene, causing amino acid mutations (T123A, M133L, and T143M) in the 'a' determinant of HBsAg that resulted in changes in the predicted antigenicity. CONCLUSIONS: OBI was detected in blood donors' samples in Indonesia. Anti-HBc was shown to be a better screening parameter than HBsAg, however, it might result in the loss of donors particularly in endemic countries. HBsAg detection failure in this study might be due to mutations altering the protein antigenicity and/or the low-level carriage of HBV.

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