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1.
J Gen Virol ; 98(5): 962-976, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28221101

RESUMO

Hepatitis C virus (HCV) is a leading cause of chronic viral hepatitis, but an effective vaccine is still not available to prevent infection. Use of neutralizing antibodies could be a potential therapeutic option. In this study, the presence of anti-HCV antibodies in HCV-infected patients was assessed from 50 patients and the presence of neutralizing antibodies was examined using 'hepatitis C virus-like particles'. Antibodies from two samples exhibited significant inhibitory activity, suggesting that these may neutralize viral infection. Antigenic determinants generating the neutralizing antibodies from these two samples were delineated by epitope mapping using the core, E1 and E2 regions and a stretch of 45 amino acid peptide (E2C45) derived from the C-terminal region of HCV-E2 protein (aa 634-679) was designed. Results suggest that this hitherto uncharacterized region has the potential to generate neutralizing antibodies against HCV and thus be effective in preventing virus entry into liver cells. Computational analysis of the structure of the modelled peptide (E2C45) suggested high conformational entropy for this region. Furthermore, E2C45 peptide-generated antibodies could block virus entry and monoclonal antibodies generated against this peptide could also significantly reduce virus replication in a cell culture system. It is possible that the inhibition could be partly due to a conformational alteration of the CD81-binding region, preventing virus attachment to liver cells. In conclusion, this work focused on the discovery of a novel epitope at the C terminus of E2 that induces potent neutralizing antibodies in HCV-infected patients.


Assuntos
Anticorpos Neutralizantes/sangue , Reações Cruzadas , Epitopos/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Linhagem Celular , Mapeamento de Epitopos , Epitopos/química , Hepacivirus/fisiologia , Anticorpos Anti-Hepatite C/imunologia , Hepatócitos/virologia , Humanos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Conformação Proteica , Proteínas do Envelope Viral/química , Internalização do Vírus/efeitos dos fármacos
2.
J Gen Virol ; 95(Pt 8): 1654-1667, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24784414

RESUMO

Persistent infection of hepatitis C virus (HCV) can lead to liver cirrhosis and hepatocellular carcinoma, which are currently diagnosed by invasive liver biopsy. Approximately 15-20 % of cases of chronic liver diseases in India are caused by HCV infection. In North India, genotype 3 is predominant, whereas genotype 1 is predominant in southern parts of India. The aim of this study was to identify differentially regulated serum proteins in HCV-infected Indian patients (genotypes 1 and 3) using a two-dimensional electrophoresis approach. We identified eight differentially expressed proteins by MS. Expression levels of one of the highly upregulated proteins, retinol-binding protein 4 (RBP4), was validated by ELISA and Western blotting in two independent cohorts. We also confirmed our observation in the JFH1 infectious cell culture system. Interestingly, the HCV core protein enhanced RBP4 levels and partial knockdown of RBP4 had a positive impact on HCV replication, suggesting a possible role for this cellular protein in regulating HCV infection. Analysis of RBP4-interacting partners using a bioinformatic approach revealed novel insights into the possible involvement of RBP4 in HCV-induced pathogenesis. Taken together, this study provided information on the proteome profile of the HCV-infected Indian population, and revealed a link between HCV infection, RBP4 and insulin resistance.


Assuntos
Hepatite C Crônica/imunologia , Proteoma/análise , Proteínas Plasmáticas de Ligação ao Retinol/análise , Soro/química , Adulto , Idoso , Western Blotting , Eletroforese em Gel Bidimensional , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Índia , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
3.
Sci Rep ; 3: 1555, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23549102

RESUMO

Changes in circulating miRNA profiles have been associated with different diseases. Here we demonstrate the circulating miRNA profile in serum of HCV infected individuals using a microRNA array that profiles the expression of 940 miRNAs. Serum samples from two HCV genotype - 1 and two HCV genotype - 3 infected individuals were compared with healthy controls. Expression levels of miR-134, miR-198, miR-320c and miR-483-5p that were commonly upregulated in case of both genotypes were validated in 36 individual patient serum samples. Serum miR-134, miR-320c and miR-483-5p were significantly upregulated during HCV infection. miR-320c and miR-483-5p were also upregulated in HCV- JFH1 infected cells and cell culture supernatant. Pathway analysis of putative target genes of these miRNAs indicated involvement of PI3K-Akt, NFKB and MAPK signaling pathways. Results revealed novel insights on the role of circulating miRNAs in mediating pathogenesis in HCV-infected cells.


Assuntos
Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite C/sangue , Hepatite C/virologia , MicroRNAs/sangue , MicroRNAs/genética , Transdução de Sinais/genética , Hepatite C/genética , Humanos , MicroRNAs/isolamento & purificação
4.
Virus Genes ; 47(1): 152-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23575989

RESUMO

In Indian population, hepatitis C virus (HCV) genotypes 1 and 3 are prevalent and predominant with the highest frequency. However, other genotypes are seldom reported, and among them the HCV genotype 5a is exceptionally rare. The presented case had no history for either blood transfusion or using any type of IV drugs and never traveled to any other country. He was serologically positive with HCV antibodies and HCV RNA. 5'UTR-specific amplification and sequencing of infected viral genome confirmed that he had been infected with HCV genotype 5a which is not closely related to other common prevalent genotypes like 1a, 1b, 3a, and 3b in India. Patient's wife and children tested negative for anti-HCV and HCV-RNA. This unique case report could be attributed to circulation of HCV genotype 5a from other geographic area at very low frequency in India as determined by phylogenetic analysis and nucleic acid-sequencing methods.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/virologia , Regiões 5' não Traduzidas , Adulto , Hepacivirus/classificação , Hepacivirus/genética , Humanos , Índia , Masculino , Dados de Sequência Molecular , Filogenia
5.
Indian J Med Microbiol ; 27(1): 12-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19172052

RESUMO

PURPOSE: To determine anti-HCV antibodies and genomic subtype of HCV in 1487 confirmed human immunodeficiency virus (HIV) positive samples. METHODS: A total of 1487 confirmed HIV-positive samples were tested for anti-HCV antibodies by using a third generation ELISA kit (Ortho 3.0) and by RT PCR for HCV. HIV and HCV coinfected samples were selected for HCV genotyping by RFLP and subtyping with NS5-type specific primers. RESULTS: A total of 1487 HIV-infected serum samples were screened for HCV infection, of which, a 1443 (97.04%) were negative and 45 (3.02%) were coinfected. HIV-HCV coinfection was predominant in the age group 41-50 years (51.1%). HCV genotyping and subtyping was done for the 45 HCV RNA-positive specimens of which genotype 1 was observed in 31 (68.8%) and genotype 3 was observed in 14 (31.1%) subjects. Further subtyping analysis showed the genotype 1b in 23 (51.1%), 1a in eight (17.7%), 3a in 10 (22.2%) and 3b in four (8.8%) subjects. CONCLUSION: HIV and HCV seroprevalence is higher in South India, and the most prevalent genotype in coinfection was genotype 1b.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/complicações , Hepatite C/epidemiologia , Adulto , Fatores Etários , Comorbidade , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Prevalência , RNA Viral/sangue , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Análise de Sequência de DNA , Proteínas não Estruturais Virais/genética , Adulto Jovem
6.
Transplant Proc ; 40(4): 1140-4, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18555134

RESUMO

This study was performed to determine the safety and tolerability of injecting autologous bone marrow stem cells (BMC) (CD34+) into four patients with liver insufficiency. The study was based on the hypothesis that the CD34+ cell population in granulocyte colony stimulating factor (G-CSF) mobilized blood and autologous bone marrow contains a subpopulation of cells with the potential for regenerating damaged tissue. We separated the CD34+ stem cell population from the bone marrow. The potential of the BMC to differentiate into hepatocytes and other cell lineages has already been reported. Several reports have also demonstrated the plasticity of hematopoietic stem cells to differentiate into hepatocytes. Recently Sakaida demonstrated reduction in fibrosis in chemically induced liver cirrhosis following BMC transplantation. From a therapeutic point of view, chronic liver cirrhosis is one of the targets for BMC transplantation. In this condition, there is excessive deposition of extracellular matrix and hepatocyte necrosis. Encouraged by this evidence that the CD34+ cell population contains cells with the potential to form hepatocyte-like elements, four patients with liver insufficiency were given G-CSF to mobilize stem cells. CD34+ cells (0.1 x 10(8)) were injected into the hepatic artery. No complications or specific side effects related to the procedure were observed; four patients showed improvements in serum albumin, bilirubin and ALT after one month from the cell infusion.


Assuntos
Transplante de Medula Óssea , Falência Hepática/cirurgia , Segurança , Transplante de Células-Tronco , Adulto , Diferenciação Celular , Doença Crônica , Feminino , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/métodos , Artéria Hepática , Hepatócitos/citologia , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Transplante Autólogo , Resultado do Tratamento
7.
Transplant Proc ; 40(4): 1148-50, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18555136

RESUMO

Crigler-Najjar Syndrome (CNS) is characterized by mild, chronic unconjugated hyperbilirubinemia resulting from an autosomal-recessive inherited deficiency of hepatic uridine/diphosphoglucuronate-glucuronosyl transferase 1Al since birth. Herein we have reported a confirmed case of CNS type 1 in a 2-year-old girl with an unconjugated hyperbilirubinemia (>30 mg/dL) treated by hepatic progenitor cell infusion through the hepatic artery. No procedure-related complications were encountered. No kernicterus was observed. The total bilirubin started falling at 10 days after cell infusion. Two months after cell infusion the bilirubin fell from 29.0 to 16 mg/dL, with the conjugated bilirubin increasing approximately fivefold, the unconjugated bilirubin decreasing nearly twofold, and the SGPT also decreasing from 210 U/L to 64 U/L. This study demonstrated the efficacy of hepatic progenitor cells to manage hyperbilirubinemia in these patients. As the procedure is simple and the patient has tolerated the cell therapy, infusion can be repeated as required to manage hyperbilirubinemia, which often causes lethal kernicterus. This study was developed to assess the safety, feasibility, and efficacy of hepatic progenitor cell transplantation in a child with CNS type 1.


Assuntos
Síndrome de Crigler-Najjar/cirurgia , Hepatócitos/transplante , Hiperbilirrubinemia/cirurgia , Transplante de Células-Tronco/métodos , Animais , Bilirrubina/sangue , Pré-Escolar , Síndrome de Crigler-Najjar/sangue , Síndrome de Crigler-Najjar/genética , Modelos Animais de Doenças , Feminino , Transplante de Tecido Fetal , Glucuronosiltransferase/genética , Artéria Hepática , Humanos , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/genética , Reação em Cadeia da Polimerase
8.
Transplant Proc ; 40(4): 1153-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18555137

RESUMO

Cholangiodestruction of bile ducts leads to biliary atresia, a rare disease characterized by intrahepatic and extrahepatic biliary inflammation. If the intrahepatic biliary tree is unaffected, surgical reconstruction by the Kasai procedure of hepatoportoenterostomy of the extra hepatic biliary tract is possible. Untreated, this condition leads to cirrhosis and death within the first year of the life. If the atresia is complete, liver transplantation is the only option. As a result of the shortage of donor livers, hepatocytes have been infused over the past two decades, providing proof of the concept that cell therapy can be effective for the treatment of liver diseases. In the present study, we report a confirmed case of a girl of 1 year of age with increased bilirubin of 28.5 mg/dL and pediatric end-stage liver disease score 20. Biochemical liver function tests showed cholestasis (elevated cholesterol and gamma-GTs) and increased ALT, total bilirubin, conjugated bilirubin, and ALP. The patient was treated with hepatic progenitor cell infusion through the hepatic artery. The total bilirubin and conjugated bilirubin started decreasing during the first month after cell infusion. The level of total bilirubin maintained a threefold decrease after months of cell infusion. The conjugated bilirubin was 16.35 mg/dL before cell infusion, decreasing to eightfold after cell infusion. After 2 months of cell infusion, hepatobiliary scintigraphy showed increased liver cell function. This case demonstrated the efficacy and functionality of hepatic progenitor cells for the management of biliary atresia. Further, as there was a decrease in serum bilirubin, it showed that there was some percentage of the engraftment of the infused cells. As the procedure is simple and the patient has tolerated the infusion therapy, it might be repeated to manage biliary atresia.


Assuntos
Transplante de Tecido Fetal/métodos , Artéria Hepática , Hepatócitos/transplante , Hiperbilirrubinemia/cirurgia , Transplante de Células-Tronco/métodos , Alanina Transaminase/sangue , Bilirrubina/sangue , Feminino , Humanos , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/enzimologia , Lactente , Fígado/enzimologia , Testes de Função Hepática
9.
Transplant Proc ; 39(3): 694-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17445575

RESUMO

Stem cell research is a new field that is advancing at an incredible pace with new discoveries being reported from all over the world. Scientists have for years looked for ways to use stem cells to replace cells and tissues that are damaged or diseased. Stem cells are the foundation cells for every organ, tissue, and cell in the body. Stem cells are undifferentiated, "blank" cells that do not yet have a specific function. Under proper conditions, stem cells begin to develop into specialized tissues and organs. They are self-sustaining and can replicate themselves for long periods of time. Embryonic stem cells are pluripotent cells, isolated from the inner cell mass of the blastocyst-stage mammalian embryo. They have the ability to differentiate into several somatic or somatic-like functional cells such as neurons, hepatocytes, cardiomyocytes, and others. Adult stem cells are specialized cells found within many tissues of the body where they function in tissue homeostasis and repair. They are precursor cells capable of differentiation into several different cells. The knowledge of stem cells from various sources offered a new hope for the treatment of various diseases.


Assuntos
Transplante de Células-Tronco/tendências , Adulto , Animais , Diabetes Mellitus/terapia , Células-Tronco Embrionárias/citologia , Cardiopatias/terapia , Humanos , Fígado/citologia , Mesoderma/citologia , Modelos Animais , Modelos Biológicos , Doenças do Sistema Nervoso/terapia , Transplante de Células-Tronco/etnologia
10.
World J Gastroenterol ; 12(44): 7136-42, 2006 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-17131475

RESUMO

AIM: to evaluate the antibacterial activity of Sapindus mukorossi (S. mukorossi) and Rheum emodi (R. emodi). METHODS: Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzene, chloroform and ethanol and were concentrated in vacuum. The disk diffusion method was used for in vitro studies and in vivo studies were performed on male Wister rats. Thirty resistant clinical isolates of H pylori, as determined by their antibiotic sensitivity patterns by E-test, along with two Gram +ve (S. aureus, B. subtilis) and two Gram -ve (E. coli, P. vugaris) organisms were screened for their susceptibility patterns against these extracts. RESULTS: In our screening, all 30 resistant isolates and the other four organisms (two Gram +ve S. aureus, B. subtilis and two Gram -ve, E. coli, P. vugaris) were sensitive to the test compounds. It was found that ethanol and chloroform extracts of S. mukorossi and ethanol and benzene extracts of R. emodi inhibited H pylori at very low concentrations. In the in vitro study, the isolates showed a considerable zone of inhibition at very low concentrations (10 mug/mL) for both the extracts. In the in vivo study, the H pylori infection was cleared with minimal doses of extracts of S. mukorossi (2.5 mg/mL) and R. emodi (3.0 mg/mL) given orally for seven days. CONCLUSION: We can conclude from this study that the extracts of S. mukorossi and R. emodi inhibited the growth of pylori in vitro and, in in vivo studies, the H pylori infection cleared within seven days at very low concentrations. We also found that H pylori did not acquire resistance against these herbal extracts even after 10 consecutive passages.


Assuntos
Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rheum/química , Sapindus/química , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Úlcera Gástrica/tratamento farmacológico
12.
Trop Gastroenterol ; 24(4): 193-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15164530

RESUMO

Viral hepatitis caused by the hepatitis C virus (HCV) and hepatitis B virus (HBV) represents a major public health problem in India. These viruses share common modes of transmission, such as parenteral routes. We aimed to assess the exposure of a tribal population to these viruses in south India. The present study was carried out on serum samples from 890 individuals (526 males and 324 females) belonging to the Lambada tribe residing in the state of Andhra Pradesh, south India. Anti-HCV antibody and hepatitis B surface antigen (HBsAg) status in the sera were analyzed using commercially available enzyme immunoassays (Abbott Labs, Chicago, IL). HCV-RNA and HBV-DNA in the sera was tested by reverse transcriptase polymerase chain reaction (RT-PCR) and PCR, respectively. The infecting genotype of HCV was determined using type-specific primers corresponding to the NS5 region of the virus. Out of the 890 samples, 18 (2.02%; male 11/526; female 7/364) were positive for HCV-RNA by RT-PCR and, 17 of them were positive for anti-HCV antibody. Genotyping of HCV isolates from the 18 individuals positive for HCV-RNA revealed that 66.67% (12/18) were infected with type 1 of HCV and its variants; while in the remaining (6/18), the infecting genotype was found to be type 3 and its variants. A total of 46 samples (5.16%; males 28/526; female 18/364) were positive for HBsAg; while 11 were positive only for HBV-DNA, 9 were positive for both hepatitis B e antigen (HBeAg) and HBV-DNA. Cultural practices such as tattooing, traditional medicine (e.g. blood-letting), rituals (e.g. scarification), body-piercing etc are the potential sources of spread of infection in this tribe. None of the samples analyzed revealed co-infection with the 2 viruses.


Assuntos
Hepacivirus/genética , Vírus da Hepatite B/genética , Hepatite B/etnologia , Hepatite C/etnologia , Adolescente , Adulto , Idoso , Criança , Feminino , Genótipo , Hepatite B/virologia , Hepatite C/virologia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Grupos Populacionais/estatística & dados numéricos , Prevalência , Fatores de Risco
13.
Acta Virol ; 45(1): 1-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11394572

RESUMO

The antibody profile to various proteins of hepatitis C virus (HCV) was studied in 113 patients positive for HCV RNA in various disease statuses of hepatitis C (HC). A single peptide (E2/NS1, aa 413-436 of HCV polyprotein) chosen from a conserved region at the C-terminus of the hypervariable region (HVR) HVR1 of HCV was found to be sufficient for reliable diagnosis of the infection, even in the acute phase. Six hundred and one suspected HC cases and 200 voluntary blood donors were tested by this peptide. The sensitivity of detection of HCV antibodies by this peptide did not increase with addition of peptides from other HCV proteins. Our results clearly demonstrate that antibodies to HCV envelope proteins occur in a higher percentage of the infected population than those to other proteins. This emphasizes the necessity of using representative sequences from HCV envelope proteins in diagnostic immunoassays of this viral infection.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/imunologia , Proteínas do Envelope Viral/imunologia , Doença Aguda , Sequência de Aminoácidos , Estudos de Casos e Controles , Epitopos/genética , Epitopos/imunologia , Hepacivirus/genética , Hepatite C/diagnóstico , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/imunologia , Humanos , Técnicas Imunoenzimáticas/métodos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Proteínas do Envelope Viral/genética
14.
Gene Geogr ; 10(1): 25-30, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8913719

RESUMO

This paper reports an extremely rare variant phenotype of Superoxide Dismutase (SODA 2) in a female individual belonging to the Shia Muslim population of Vizianagaram, Andhra Pradesh, South India whose parents are not consanguineous. This is the third report in the world so far. The corresponding SODA phenotype of other family members of the proposita were also investigated. The results and their significance are discussed in the light of earlier works in India and world populations.


Assuntos
Variação Genética , Superóxido Dismutase/genética , Adulto , Alelos , Criança , Feminino , Frequência do Gene , Humanos , Índia , Islamismo , Masculino , Fenótipo
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