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1.
Int J Mol Sci ; 22(13)2021 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-34206987

RESUMEN

Hepatitis C virus (HCV) is one of the main triggers of chronic liver disease. Despite tremendous progress in the HCV field, there is still no vaccine against this virus. Potential vaccines can be based on its recombinant proteins. To increase the humoral and, especially, cellular immune response to them, more effective adjuvants are needed. Here, we evaluated a panel of compounds as potential adjuvants using the HCV NS5B protein as an immunogen. These compounds included inhibitors of polyamine biosynthesis and urea cycle, the mTOR pathway, antioxidants, and cellular receptors. A pronounced stimulation of cell proliferation and interferon-γ (IFN-γ) secretion in response to concanavalin A was shown for antioxidant N-acetylcysteine (NAC), polyamine biosynthesis inhibitor 2-difluoromethylornithine (DFMO), and TLR9 agonist CpG ODN 1826 (CpG). Their usage during the immunization of mice with the recombinant NS5B protein significantly increased antibody titers, enhanced lymphocyte proliferation and IFN-γ production. NAC and CpG decreased relative Treg numbers; CpG increased the number of myeloid-derived suppressor cells (MDSCs), whereas neither NAC nor DFMO affected MDSC counts. NAC and DFMO suppressed NO and interleukin 10 (IL-10) production by splenocytes, while DFMO increased the levels of IL-12. This is the first evidence of immunomodulatory activity of NAC and DFMO during prophylactic immunization against infectious diseases.


Asunto(s)
Acetilcisteína/farmacología , Adyuvantes Inmunológicos/farmacología , Eflornitina/farmacología , Hepatitis C/inmunología , Inmunidad Activa/efectos de los fármacos , Proteínas no Estructurales Virales/inmunología , Animales , Proliferación Celular , Células Cultivadas , Femenino , Inmunogenicidad Vacunal/efectos de los fármacos , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Ratones , Ratones Endogámicos DBA , Células Supresoras de Origen Mieloide/efectos de los fármacos , Células Supresoras de Origen Mieloide/inmunología , Óxido Nítrico/metabolismo , Oligodesoxirribonucleótidos/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Vacunas contra Hepatitis Viral/inmunología
2.
BMC Gastroenterol ; 20(1): 1, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31892306

RESUMEN

BACKGROUND: The multifactorial mechanisms driving negative health outcomes among risky drinkers with HIV may include immunosenescence. Immunosenescence, aging of the immune system, may be accentuated in HIV and leads to poor outcomes. The liver regulates innate immunity and adaptive immune tolerance. HIV-infected people have high prevalence of liver-related comorbidities. We hypothesize that advanced liver fibrosis/cirrhosis is associated with alterations in T-cell subsets consistent with immunosenescence. METHODS: ART-naïve people with HIV with a recent history of heavy drinking were recruited into a clinical trial of zinc supplementation. Flow cytometry was used to characterize T-cell subsets. The two primary dependent variables were CD8+ and CD4+ T-cells expressing CD28-CD57+ (senescent cell phenotype). Secondary dependent variables were CD8+ and CD4+ T-cells expressing CD45RO + CD45RA- (memory phenotype), CD45RO-CD45RA+ (naïve phenotype), and the naïve phenotype to memory phenotype T-cell ratio (lower ratios associated with immunosenescence). Advanced liver fibrosis/cirrhosis was defined as FIB-4 > 3.25, APRI≥1.5, or Fibroscan measurement ≥10.5 kPa. Analyses were conducted using multiple linear regression adjusted for potential confounders. RESULTS: Mean age was 34 years; 25% female; 88% hepatitis C. Those with advanced liver fibrosis/cirrhosis (N = 25) had higher HIV-1 RNA and more hepatitis C. Advanced liver fibrosis/cirrhosis was not significantly associated with primary or secondary outcomes in adjusted analyses. CONCLUSIONS: Advanced liver fibrosis/cirrhosis was not significantly associated with these senescent T-cell phenotypes in this exploratory study of recent drinkers with HIV. Future studies should assess whether liver fibrosis among those with HIV viral suppression and more advanced, longstanding liver disease is associated with changes in these and other potentially senescent T-cell subsets.


Asunto(s)
Alcoholismo/complicaciones , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Infecciones por VIH/inmunología , Inmunosenescencia , Cirrosis Hepática Alcohólica/inmunología , Adulto , Antígenos CD28/metabolismo , Linfocitos T CD4-Positivos/inmunología , Antígenos CD57/metabolismo , Linfocitos T CD8-positivos/inmunología , Estudios Transversales , Femenino , Infecciones por VIH/complicaciones , Hepatitis C/inmunología , Humanos , Memoria Inmunológica , Antígenos Comunes de Leucocito/metabolismo , Modelos Lineales , Cirrosis Hepática Alcohólica/diagnóstico por imagen , Cirrosis Hepática Alcohólica/enzimología , Cirrosis Hepática Alcohólica/patología , Masculino , Fenotipo , Ensayos Clínicos Controlados Aleatorios como Asunto , Federación de Rusia , Zinc/administración & dosificación
3.
World J Gastroenterol ; 23(32): 5895-5903, 2017 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-28932081

RESUMEN

AIM: To investigate the effect of (-)-epigallocatechin-3-gallate (EGCG) on polyinosinic-polycytidylic acid (poly I:C)-triggered intracellular innate immunity against hepatitis C virus (HCV) in hepatocytes. METHODS: A cell culture model of HCV infection was generated by infecting a hepatoma cell line, Huh7, with HCV JFH-1 strain (JFH-1-Huh7). Poly I:C with a high molecular weight and EGCG were used to stimulate the JFH-1-Huh7 cells. Real-time reverse transcription-polymerase chain reaction was used to detect the expression levels of intracellular mRNAs and of intracellular and extracellular HCV RNA. Enzyme-linked immunosorbent assay was used to evaluate the interferon (IFN)-λ1 protein level in the cell culture supernatant. Immunostaining was used to examine HCV core protein expression in Huh7 cells. RESULTS: Our recent study showed that HCV replication could impair poly I:C-triggered intracellular innate immune responses in hepatocytes. In the current study, we showed that EGCG treatment significantly increased the poly I:C-induced expression of Toll-like receptor 3 (TLR3), retinoic acid-inducible gene I, and IFN-λ1 in JFH-1-Huh7 cells. In addition, supplementation with EGCG increased the poly I:C-mediated antiviral activity in JFH-1-Huh7 cells at the intracellular and extracellular HCV RNA and protein levels. Further investigation of the mechanisms showed that EGCG treatment significantly enhanced the poly I:C-induced expression of IFN-regulatory factor 9 and several antiviral IFN-stimulated genes, including ISG15, ISG56, myxovirus resistance A, and 2'-5'-oligoadenylate synthetase 1, which encode the key antiviral elements in the IFN signaling pathway. CONCLUSION: Our observations provide experimental evidence that EGCG has the ability to enhance poly I:C-induced intracellular antiviral innate immunity against HCV replication in hepatocytes.


Asunto(s)
Antivirales/farmacología , Catequina/análogos & derivados , Hepacivirus/fisiología , Hepatitis C/inmunología , Inmunidad Innata/efectos de los fármacos , Interferón gamma/inmunología , Poli I-C/inmunología , Antivirales/uso terapéutico , Catequina/farmacología , Catequina/uso terapéutico , Línea Celular Tumoral , Proteína 58 DEAD Box/inmunología , Proteína 58 DEAD Box/metabolismo , Ensayo de Inmunoadsorción Enzimática , Hepatitis C/tratamiento farmacológico , Hepatitis C/virología , Hepatocitos , Humanos , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/inmunología , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Interferón gamma/metabolismo , ARN Viral/aislamiento & purificación , Receptores Inmunológicos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/inmunología , Receptor Toll-Like 3/metabolismo , Proteínas del Núcleo Viral/metabolismo , Replicación Viral/efectos de los fármacos , Replicación Viral/inmunología
4.
BMC Infect Dis ; 16: 249, 2016 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-27267370

RESUMEN

BACKGROUND: Prisoners represent a vulnerable population for blood-borne and sexually transmitted infections which can potentially lead to liver fibrosis and ultimately cirrhosis. However, little is known about the prevalence of liver fibrosis and associated risk factors among inmates in sub-Saharan Africa. METHODS: Screening of liver fibrosis was undertaken in a randomly selected sample of male inmates incarcerated in Lome, Togo and in Dakar, Senegal using transient elastography. A liver stiffness measurement ≥9.5 KPa was retained to define the presence of a severe liver fibrosis. All included inmates were also screened for HIV, Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) infection. Substances abuse including alcohol, tobacco and cannabis use were assessed during face-to-face interviews. Odds Ratio (OR) estimates were computed with their 95 % Confidence Interval (CI) to identify factors associated with severe liver fibrosis. RESULTS: Overall, 680 inmates were included with a median age of 30 years [interquartile range: 24-35]. The prevalence of severe fibrosis was 3.1 % (4.9 % in Lome and 1.2 % in Dakar). Infections with HIV, HBV and HCV were identified in 2.6 %, 12.5 % and 0.5 % of inmates, respectively. Factors associated with a severe liver fibrosis were HIV infection (OR = 7.6; CI 1.8-32.1), HBV infection (OR = 4.8; CI 1.8-12.8), HCV infection (OR = 52.6; CI 4.1-673.8), use of traditional medicines (OR = 3.7; CI 1.4-10.1) and being incarcerated in Lome (OR = 3.3; CI 1.1-9.8) compared to Dakar. CONCLUSIONS: HIV infection and viral hepatitis infections were identified as important and independent determinants of severe liver fibrosis. While access to active antiviral therapies against HIV and viral hepatitis expands in Africa, adapted strategies for the monitoring of liver disease need to be explored, especially in vulnerable populations such as inmates.


Asunto(s)
Infecciones por VIH/epidemiología , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Cirrosis Hepática/epidemiología , Prisioneros/estadística & datos numéricos , Adulto , África Occidental/epidemiología , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Coinfección/epidemiología , Comorbilidad , ADN Viral/sangre , Diagnóstico por Imagen de Elasticidad , Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Hepatitis C/sangre , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/inmunología , Humanos , Hígado/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Masculino , Medicinas Tradicionales Africanas/estadística & datos numéricos , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Senegal/epidemiología , Índice de Severidad de la Enfermedad , Factores de Tiempo , Togo/epidemiología , Carga Viral , Adulto Joven
5.
J Immunol ; 196(5): 2283-92, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26826241

RESUMEN

The hepatitis C virus (HCV) infects ∼ 200 million people worldwide. The majority of infected individuals develop persistent infection, resulting in chronic inflammation and liver disease, including cirrhosis and hepatocellular carcinoma. The ability of HCV to establish persistent infection is partly due to its ability to evade the immune response through multiple mechanisms, including suppression of NK cells. NK cells control HCV replication during the early phase of infection and regulate the progression to chronic disease. In particular, IFN-γ produced by NK cells limits viral replication in hepatocytes and is important for the initiation of adaptive immune responses. However, NK cell function is significantly impaired in chronic HCV patients. The cellular and molecular mechanisms responsible for impaired NK cell function in HCV infection are not well defined. In this study, we analyzed the interaction of human NK cells with CD33(+) PBMCs that were exposed to HCV. We found that NK cells cocultured with HCV-conditioned CD33(+) PBMCs produced lower amounts of IFN-γ, with no effect on granzyme B production or cell viability. Importantly, this suppression of NK cell-derived IFN-γ production was mediated by CD33(+)CD11b(lo)HLA-DR(lo) myeloid-derived suppressor cells (MDSCs) via an arginase-1-dependent inhibition of mammalian target of rapamycin activation. Suppression of IFN-γ production was reversed by l-arginine supplementation, consistent with increased MDSC arginase-1 activity. These novel results identify the induction of MDSCs in HCV infection as a potent immune evasion strategy that suppresses antiviral NK cell responses, further indicating that blockade of MDSCs may be a potential therapeutic approach to ameliorate chronic viral infections in the liver.


Asunto(s)
Arginasa/metabolismo , Hepacivirus/inmunología , Interferón gamma/biosíntesis , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Células Mieloides/inmunología , Células Mieloides/metabolismo , Arginina/metabolismo , Línea Celular , Células Cultivadas , Hepatitis C/genética , Hepatitis C/inmunología , Hepatitis C/metabolismo , Hepatitis C/virología , Humanos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/virología , Células Mieloides/virología , Procesamiento Postranscripcional del ARN , Lectina 3 Similar a Ig de Unión al Ácido Siálico/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
6.
Genet Mol Res ; 14(2): 4957-65, 2015 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-25966271

RESUMEN

The traditional Chinese medicine Artemisia annua can prevent and treat hepatitis following an unclear mechanism. The aim of this study was to evaluate the effects of A. annua polysaccharides (AAP) on hepatitis C virus (HCV). A pcDNA3.1/NS3 expression vector was constructed. Ninety female BALB/c mice were randomly divided into six groups: high-dose AAP (1 mg/mL) + HCV/NS3 plasmid; middle-dose AAP (0.5 mg/mL) + HCV/NS3 plasmid; low-dose AAP (0.1 mg/mL) + HCV/NS3 plasmid; HCV/NS3 plasmid; high-dose AAP (1 mg/mL); normal saline control (N = 15). Except the control group and the high-dose AAP group, other groups were inoculated with 50 µg pcDNA3.1-HCV/NS3 plasmid. Serum antigenic-specific antibody was detected after the last immunization, and the levels of secreted IFN-γ and IL-4 were measured. pcDNA3.1/NS3 plasmid was successfully constructed, and the extracted product contained HCV/NS3 sequence. Compared with single inoculation with HCV/NS3 DNA vaccine, the specific antibody levels induced by middle-dose AAP plus HCV/NS3 DNA vaccine were significantly different in weeks 1, 3 and 5 (P < 0.05). However, there were no significant differences in the antibody levels induced by high-dose and low-dose AAP as adjuvant compared with those of single inoculation with DNA vaccine (P > 0.05). The level of serum IFN-γ secretion was significantly higher than that of IL-4 secretion. Compared with the single HCV/NS3 DNA vaccine group, AAP plus HCV/NS3 DNA vaccine groups had significant increased IFN-γ levels (P < 0.05), but the IL-4 levels were not significantly different among these groups (P > 0.05). AAP, as the adjuvant of HCV/NS3 DNA vaccine, can widely regulate the humoral immunity and cellular immune function of normal and cyclophosphamide-induced immunocompromised mice. AAP can promote IFN-γ secretion probably by inducing Th1-type cellular immune response.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Hepatitis C/prevención & control , Polisacáridos/administración & dosificación , Vacunación , Animales , Artemisia annua/química , Artemisia annua/inmunología , Femenino , Hepatitis C/inmunología , Hepatitis C/patología , Humanos , Ratones , Polisacáridos/inmunología
7.
Arch Virol ; 160(4): 945-58, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25631616

RESUMEN

The present work aimed at 1) characterization of the E1 and E2 proteins (HCV-E) from an Egyptian hepatitis C virus genotype 4a (HCV-4a) isolate at the molecular and immunological level, 2) in silico identification of the B- and T-cell epitopes responsible for the immunogenicity of HCV-E, and 3) evaluation of the diagnostic potential of both the recombinant HCV-E and antibodies raised using mammalian expression constructs encoding the protein. The region encoding the E1 and E2 proteins was amplified by RT-PCR from RNA isolated from blood of a human infected with HCV-4 and cloned into the pSC-TA plasmid, and the sequence was verified and used to construct a neighbor-joining phylogenetic tree. The translated nucleotide sequence was used to predict the HCV-E secondary structure using the PREDICT-PROTEIN server and PSI-PRED. A 3D model of HCV-E was generated using the online tool 3Dpro. B- and T-cell epitopes were predicted using the online tools BCPred and Epijen v1.0, respectively. The HCV-E-encoding sequence was later subcloned into the mammalian expression plasmid pQE, and the constructs that were generated were used to immunize mice in the absence and presence of adjuvants of plant origin. The maximum sequence identity obtained by nucleotide and protein BLAST analysis with previously published HCV-E sequences was 85 and 77 %, respectively. The B-cell epitope CFTPSPVVV at position 203 and the T-cell epitope ALSTGLIHL at position 380 were found to be highly conserved among all HCV genotypes. Both ELISA and Western blotting experiments on crude and purified recombinant HCV envelope proteins using mouse antisera raised using the HCV-E mammalian expression construct confirmed the specific antigenicity of the expressed protein. The antibodies raised in mice using the HCV-E-encoding construct could efficiently capture circulating antigens in patients' sera with good sensitivity that correlated with liver enzyme levels (r = 0.4052, P < 0.0001 for ALT; r = -0.5439, P = 0.0019 for AST). Moreover, combining the HCV-E-encoding construct with extracts prepared from Echinacea purpurea and Nigella sativa prior to immunizing mice significantly (P < 0.05) increased both the humoral (14.9- to 20-fold increase in antibodies) and the cellular (CD4(+) and cytotoxic CD8(+)- T lymphocytes) responses compared to mice that received the DNA construct alone or PBS-treated mice. Both recombinant HCV-E protein preparations and antibodies raised using the HCV-E-encoding mammalian expression construct represent useful diagnostic tools that can report on active HCV infection. Also, the immunostimulatory effects induced by the two plant extracts used at the cellular and humoral level highlight the potential of natural products for inducing protection against HCV infection. The neutralizing capacity of the induced antibodies is a subject of future investigations. Furthermore, the predicted B- and T-cell epitopes may be useful for tailoring future diagnostics and candidate vaccines against various HCV genotypes.


Asunto(s)
Hepacivirus/inmunología , Hepatitis C/virología , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología , Animales , Echinacea/genética , Echinacea/metabolismo , Egipto , Epítopos de Linfocito B/inmunología , Epítopos de Linfocito T/inmunología , Femenino , Expresión Génica , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/diagnóstico , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/inmunología , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Datos de Secuencia Molecular , Nigella sativa/genética , Nigella sativa/metabolismo , Filogenia , Alineación de Secuencia , Proteínas del Envoltorio Viral/química
8.
PLoS One ; 9(7): e102235, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25014219

RESUMEN

Hepatitis C virus (HCV) infection is still a serious global health burden. Despite improved therapeutic options, a preventative vaccine would be desirable especially in undeveloped countries. Traditionally, highly conserved epitopes are targets for antibody-based prophylactic vaccines. In HCV-infected patients, however, neutralizing antibodies are primarily directed against hypervariable region I (HVRI) in the envelope protein E2. HVRI is the most variable region of HCV, and this heterogeneity contributes to viral persistence and has thus far prevented the development of an effective HVRI-based vaccine. The primary goal of an antibody-based HCV vaccine should therefore be the induction of cross-reactive HVRI antibodies. In this study we approached this problem by presenting selected cross-reactive HVRI variants in a highly symmetric repeated array on capsid-like particles (CLPs). SplitCore CLPs, a novel particulate antigen presentation system derived from the HBV core protein, were used to deliberately manipulate the orientation of HVRI and therefore enable the presentation of conserved parts of HVRI. These HVRI-CLPs induced high titers of cross-reactive antibodies, including neutralizing antibodies. The combination of only four HVRI CLPs was sufficient to induce antibodies cross-reactive with 81 of 326 (24.8%) naturally occurring HVRI peptides. Most importantly, HVRI CLPs with AS03 as an adjuvant induced antibodies with a 10-fold increase in neutralizing capability. These antibodies were able to neutralize infectious HCVcc isolates and 4 of 19 (21%) patient-derived HCVpp isolates. Taken together, these results demonstrate that the induction of at least partially cross-neutralizing antibodies is possible. This approach might be useful for the development of a prophylactic HCV vaccine and should also be adaptable to other highly variable viruses.


Asunto(s)
Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Antivirales/biosíntesis , Hepacivirus/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis C/prevención & control , Vacunas contra Hepatitis Viral/inmunología , Proteínas Virales/inmunología , Animales , Presentación de Antígeno , Antígenos Virales/química , Antígenos Virales/genética , Antígenos Virales/inmunología , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Protección Cruzada , Combinación de Medicamentos , Escherichia coli/genética , Escherichia coli/metabolismo , Femenino , Expresión Génica , Virus de la Hepatitis B/genética , Hepatitis C/inmunología , Hepatitis C/virología , Humanos , Inmunidad Humoral , Inyecciones Intramusculares , Inyecciones Subcutáneas , Ratones , Ratones Endogámicos C57BL , Polisorbatos/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Escualeno/administración & dosificación , Vacunas contra Hepatitis Viral/administración & dosificación , Vacunas contra Hepatitis Viral/genética , Proteínas Virales/química , Proteínas Virales/genética , alfa-Tocoferol/administración & dosificación
9.
PLoS Pathog ; 10(6): e1004210, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24967632

RESUMEN

The ability of innate immune cells to sense and respond to impending danger varies by anatomical location. The liver is considered tolerogenic but is still capable of mounting a successful immune response to clear various infections. To understand whether hepatic immune cells tune their response to different infectious challenges, we probed mononuclear cells purified from human healthy and diseased livers with distinct pathogen-associated molecules. We discovered that only the TLR8 agonist ssRNA40 selectively activated liver-resident innate immune cells to produce substantial quantities of IFN-γ. We identified CD161(Bright) mucosal-associated invariant T (MAIT) and CD56(Bright) NK cells as the responding liver-resident innate immune cells. Their activation was not directly induced by the TLR8 agonist but was dependent on IL-12 and IL-18 production by ssRNA40-activated intrahepatic monocytes. Importantly, the ssRNA40-induced cytokine-dependent activation of MAIT cells mirrored responses induced by bacteria, i.e., generating a selective production of high levels of IFN-γ, without the concomitant production of TNF-α or IL-17A. The intrahepatic IFN-γ production could be detected not only in healthy livers, but also in HBV- or HCV-infected livers. In conclusion, the human liver harbors a network of immune cells able to modulate their immunological responses to different pathogen-associated molecules. Their ability to generate a strong production of IFN-γ upon stimulation with TLR8 agonist opens new therapeutic opportunities for the treatment of diverse liver pathologies.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Inmunidad Innata/efectos de los fármacos , Leucocitos Mononucleares/efectos de los fármacos , Hígado/efectos de los fármacos , Oligorribonucleótidos/farmacología , Receptor Toll-Like 8/agonistas , Regulación hacia Arriba/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Enterococcus faecalis/inmunología , Enterococcus faecalis/metabolismo , Enterococcus faecalis/patogenicidad , Escherichia coli/inmunología , Escherichia coli/metabolismo , Escherichia coli/patogenicidad , Hepacivirus/inmunología , Hepacivirus/patogenicidad , Hepatitis B/inmunología , Hepatitis B/metabolismo , Hepatitis B/patología , Hepatitis B/virología , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/patogenicidad , Hepatitis C/inmunología , Hepatitis C/metabolismo , Hepatitis C/patología , Hepatitis C/virología , Humanos , Ensayos de Liberación de Interferón gamma , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Hígado/inmunología , Hígado/microbiología , Hígado/patología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Monocitos/metabolismo , Pseudomonas aeruginosa/inmunología , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidad , Riboflavina/biosíntesis , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Receptor Toll-Like 8/metabolismo
10.
Hum Vaccin Immunother ; 9(5): 1112-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23406827

RESUMEN

Given the global prevalence and long-term complications of chronic hepatitis C virus (HCV) infection, HCV constitutes one of the greatest challenges to human health of this decade. Considerable efforts have focused on the development of new effective treatments, but about three to four million individuals become infected each year, adding to the world reservoir of HCV infection. The development of a prophylactic vaccine against hepatitis C virus has thus become an important medical priority. Only a few vaccine candidates have progressed to the clinical phase, and published data on both the efficacy and safety of these vaccines are limited, due to many scientific, logistic and bioethic challenges. Fortunately, new innovative vaccine formulations, modes of vaccination and delivery technologies have been developed in recent years. Several preclinical trials of virus-like particle (VLP)-based vaccination strategies are currently underway and have already generated very promising results. In this commentary, we consider the current state of prophylactic HCV vaccines, the hurdles to be overcome in the future and the various VLP-based vaccination approaches currently being developed.


Asunto(s)
Hepacivirus/inmunología , Hepatitis C/prevención & control , Vacunas de Partículas Similares a Virus/inmunología , Vacunas Virales/inmunología , Descubrimiento de Drogas/tendencias , Evaluación Preclínica de Medicamentos , Hepacivirus/genética , Hepatitis C/inmunología , Humanos , Vacunas de Partículas Similares a Virus/administración & dosificación , Vacunas de Partículas Similares a Virus/genética , Vacunas Virales/administración & dosificación , Vacunas Virales/genética
11.
Clin Endocrinol (Oxf) ; 78(4): 621-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22957689

RESUMEN

CONTEXT: One of the side effects of interferon-alpha therapy is interferon-induced thyroiditis (IIT). The role of lymphocyte subpopulations in IIT melanoma patients remains to be defined. OBJECTIVE: Our objective was to assess different peripheral blood lymphocyte subpopulations, mainly regulatory T cells (Tregs), in melanoma patients who developed IIT. DESIGN, PATIENTS AND METHODS: From 30 melanoma patients receiving high-dose interferon (HDI)-alpha 2b (IFN-α2b) treatment, those who developed IIT (IIT patients) were selected and compared with patients who did not develop IIT (Co-MM) and healthy controls (Co-H). Peripheral blood mononuclear cells were obtained before treatment (BT), mid-treatment (MT), end of treatment (ET), 24 weeks post-treatment and at appearance of IIT (TT). RESULTS: Nine patients developed IIT (30%): four Hashimoto's thyroiditis and five destructive thyroiditis. An increase in Tregs was observed in both melanoma groups during HDI treatment. A decrease in CD3(+) , NKT lymphocyte subpopulations and Bcl2 expression on B cells was also observed in both groups. However, no changes were observed in the percentage of CD4(+) , CD8(+) , CD3(+) γδ(+) , CD19(+) , transitional B cells (CD24(high) CD38(high) CD19(+) CD27(-) ), natural killer (NK), invariant NKT (iNKT) lymphocytes and Th1/Th2 balance when BT was compared with ET. At TT, IIT patients had a higher Tregs percentage than Co-MM (P = 0·012) and Co-H (P = 0·004), a higher iNKT percentage than Co-MM (P = 0·011), a higher transitional B cells percentage than Co-H (P = 0·015), a lower CD3(+) percentage than Co-H (P = 0·001) and a lower Bcl2 expression on B cells than Co-H (P < 0·001). CONCLUSIONS: Our results point to the immunomodulatory effects of IFN-α on different lymphocyte subpopulations and a possible role of Tregs in melanoma patients who developed IIT.


Asunto(s)
Interferón-alfa/efectos adversos , Subgrupos Linfocitarios/patología , Melanoma/inmunología , Neoplasias Cutáneas/inmunología , Linfocitos T Reguladores/patología , Tiroiditis/inducido químicamente , Adulto , Antivirales/efectos adversos , Antivirales/uso terapéutico , Femenino , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C/inmunología , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferón-alfa/uso terapéutico , Masculino , Melanoma/complicaciones , Melanoma/tratamiento farmacológico , Melanoma/patología , Persona de Mediana Edad , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Pruebas de Función de la Tiroides , Tiroiditis/inmunología , Tiroiditis/patología , Adulto Joven
12.
Autoimmun Rev ; 12(3): 430-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22940579

RESUMEN

Monoclonal marginal zone (MZ) B cells expressing a V(H)1-69-encoded idiotype accumulate in HCV-associated mixed cryoglobulinemia (MC). These cells recognize the E2 protein of HCV and their massive clonal expansion reflects the propensity of MZ B cells to proliferate robustly upon antigenic stimulation by microorganisms, a property that makes them prone to neoplastic transformation. V(H)1-69(+) B cells of MC patients are phenotypically heterogeneous and resemble either mature MZ B cells (IgM(+)CD27(+)CD21(high)) or the unusual CD21(low) B cells that accumulate in other immunological disorders such as common variable immunodeficiency (CVID) or HIV infection. The CD21(low) V(H)1-69(+) B cells of MC patients, like those of CVID and HIV patients, are anergic to BCR and TLR9 stimulation and display deregulation of several anergy-related genes; proliferative anergy is also observed in CD21(high) MZ-like V(H)1-69(+) B cells, that over-express the antiproliferative transcriptional repressor Stra13. Upon evolution to splenic marginal zone lymphoma, MZ-like V(H)1-69(+) B cells down-regulate Stra13 and partially recover their capacity to proliferate in response to TLR9 ligation. Like yin and yang, robust clonal expansion and early proliferative anergy may be viewed as the opposite forces balancing the responses of human MZ B cells to chronic microbial stimuli. Disruption of this balance facilitates autoimmunity and lymphoproliferation.


Asunto(s)
Autoinmunidad , Linfocitos B/citología , Linfocitos B/inmunología , Crioglobulinemia/inmunología , Crioglobulinemia/virología , Hepacivirus/inmunología , Activación de Linfocitos , Crioglobulinemia/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hepatitis C/inmunología , Hepatitis C/patología , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Receptores de Complemento 3d/metabolismo , Bazo/inmunología
13.
J Viral Hepat ; 19(1): 1-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22187942

RESUMEN

Hepatitis C virus (HCV) infection is a major cause for liver transplantation worldwide. Still, HCV re-infection of the graft occurs in almost all cases. Most liver transplant recipients experience episodes of graft hepatitis associated with fibrosis progression and graft failure. Clinical management of graft hepatitis can be challenging as in addition to rejection and HCV-induced hepatitis various other factors might be involved including toxic liver injury, steatohepatitis, ischaemic bile duct lesions or infections with other pathogens. Treatment options are often contradictory for different causes of graft hepatitis, and the role of distinct immunosuppressive drugs has been discussed controversially. Corticosteroids increase the infectivity of HCV by altering expression levels of entry factors and other immunosuppressive agents may have diverse effects on HCV replication and fibrosis progression. Interferon alpha-therapy of hepatitis C shows limited efficacy and tolerability in liver transplant recipients and may also cause rejection. In this review we summarize the current knowledge on mechanisms of liver injury in post-transplant hepatitis C, discuss the pros and cons of immunosuppressive agents in this specific setting and describe potential novel approaches to prevent HCV reinfection.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/patogenicidad , Hepatitis C/prevención & control , Inmunosupresores/uso terapéutico , Trasplante de Hígado/efectos adversos , Anticuerpos Neutralizantes/uso terapéutico , Hepatitis C/tratamiento farmacológico , Hepatitis C/inmunología , Hepatitis C/patología , Humanos , Terapia de Inmunosupresión , Interferón-alfa/uso terapéutico , Hígado/patología , Prevención Secundaria , Silibina , Silimarina/uso terapéutico
14.
J Altern Complement Med ; 17(12): 1181-90, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22132706

RESUMEN

BACKGROUND: Reiki therapy is documented for relief of pain and stress. Energetic healing has been documented to alter biologic markers of illness such as hematocrit. True random number generators are reported to be affected by energy healers and spiritually oriented conscious awareness. METHODS: The patient was a then 54-year-old severely ill man who had hepatitis C types 1 and 2 and who did not improve with conventional therapy. He also suffered from obesity, the metabolic syndrome, asthma, and hypertension. He was treated with experimental high-dose interferon/riboviron therapy with resultant profound anemia and neutropenia. Energetic healing and Reiki therapy was administered initially to enhance the patient's sense of well-being and to relieve anxiety. Possible effects on the patient's absolute neutrophil count and hematocrit were incidentally noted. Reiki therapy was then initiated at times of profound neutropenia to assess its possible effect on the patient's absolute neutrophil count (ANC). Reiki and other energetic healing sessions were monitored with a true random number generator (RNG). RESULTS: Statistically significant relationships were documented between Reiki therapy, a quieting of the electronically created white noise of the RNG during healing sessions, and improvement in the patient's ANC. The immediate clinical result was that the patient could tolerate the high-dose interferon regimen without missing doses because of absolute neutropenia. The patient was initially a late responder to interferon and had been given a 5% chance of clearing the virus. He remains clear of the virus 1 year after treatment. CONCLUSIONS: The association between changes in the RNG, Reiki therapy, and a patient's ANC is the first to the authors' knowledge in the medical literature. Future studies assessing the effects of energetic healing on specific biologic markers of disease are anticipated. Concurrent use of a true RNG may prove to correlate with the effectiveness of energetic therapy.


Asunto(s)
Hepatitis C/tratamiento farmacológico , Interferones/efectos adversos , Relaciones Metafisicas Mente-Cuerpo , Neutropenia/terapia , Neutrófilos/metabolismo , Ribavirina/efectos adversos , Tacto Terapéutico , Ansiedad/terapia , Estado de Conciencia , Hematócrito , Hepacivirus , Hepatitis C/complicaciones , Hepatitis C/inmunología , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neutropenia/etiología , Índice de Severidad de la Enfermedad , Espiritualidad
15.
World J Gastroenterol ; 16(16): 1943-52, 2010 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-20419831

RESUMEN

Insulin resistance is one of the pathological features in patients with hepatitis C virus (HCV) infection. Generally, persistence of insulin resistance leads to an increase in the risk of life-threatening complications such as cardiovascular diseases. However, these complications are not major causes of death in patients with HCV-associated insulin resistance. Indeed, insulin resistance plays a crucial role in the development of various complications and events associated with HCV infection. Mounting evidence indicates that HCV-associated insulin resistance may cause (1) hepatic steatosis; (2) resistance to anti-viral treatment; (3) hepatic fibrosis and esophageal varices; (4) hepatocarcinogenesis and proliferation of hepatocellular carcinoma; and (5) extrahepatic manifestations. Thus, HCV-associated insulin resistance is a therapeutic target at any stage of HCV infection. Although the risk of insulin resistance in HCV-infected patients has been documented, therapeutic guidelines for preventing the distinctive complications of HCV-associated insulin resistance have not yet been established. In addition, mechanisms for the development of HCV-associated insulin resistance differ from lifestyle-associated insulin resistance. In order to ameliorate HCV-associated insulin resistance and its complications, the efficacy of the following interventions is discussed: a late evening snack, coffee consumption, dietary iron restriction, phlebotomy, and zinc supplements. Little is known regarding the effect of anti-diabetic agents on HCV infection, however, a possible association between use of exogenous insulin or a sulfonylurea agent and the development of HCC has recently been reported. On the other hand, insulin-sensitizing agents are reported to improve sustained virologic response rates. In this review, we summarize distinctive complications of, and therapeutic strategies for, HCV-associated insulin resistance. Furthermore, we discuss supplementation with branched-chain amino acids as a unique insulin-sensitizing strategy for patients with HCV-associated insulin resistance.


Asunto(s)
Hepacivirus/metabolismo , Hepatitis C/complicaciones , Hepatitis C/virología , Resistencia a la Insulina , Insulina/metabolismo , Antivirales/farmacología , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/virología , Proliferación Celular , Várices Esofágicas y Gástricas/virología , Hígado Graso/patología , Fibrosis/virología , Hepatitis C/inmunología , Humanos , Insulina/uso terapéutico , Estilo de Vida , Hígado/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/virología
16.
Adv Drug Deliv Rev ; 59(12): 1196-9, 2007 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-17905463

RESUMEN

Hepatitis C virus (HCV) causes persistent infection and induces chronic hepatitis, liver cirrhosis and finally hepatocellular carcinoma. Current therapies for HCV infection have not been satisfactory, and more effective anti-viral treatments are needed. In this regard, detailed analysis of HCV has been hampered by a lack of appropriate viral culture systems and small animal models of infection. However, rapid progress in HCV research has recently been achieved, such as a subgenomic replicon system, a viral culture system using JFH-1 clone and the Alb-uPA/SCID mouse transplanted with human liver cells. Such progress will propel HCV research and anti-HCV drug discovery toward the next generation.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/fisiología , Hepatitis C/tratamiento farmacológico , Animales , Línea Celular , Evaluación Preclínica de Medicamentos/métodos , Hepacivirus/genética , Hepatitis C/inmunología , Hepatitis C/prevención & control , Humanos , Interferones/uso terapéutico , Ratones , Pan troglodytes , Replicón/genética , Ribavirina/uso terapéutico , Vacunas/inmunología , Replicación Viral/genética
17.
Int Rev Psychiatry ; 17(6): 471-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16401545

RESUMEN

More than 4 million people are currently infected with Hepatitis C an RNA virus that may ultimately result in complete hepatic failure and is often a silent infection until late in the course of disease. Hepatitis C patients have increased rates of major depression (as well as substance abuse) and treatment of hepatitis with interferon, the current standard treatment, provokes episodes of depression in as many as a third of patients treated. Immune-dysfunction mediated mechanisms for the depression in these patients have been proposed and have increasing experimental support. The resulting depression has interfered with treatment for many patients, but several standard treatments for depression have been shown to be effective in patients with interferon-associated depression, suggesting that this should not be a barrier to effective treatment. In this paper, we review the evidence for associations between depression and Hepatitis C and interferon treatment, as well as the evidence supporting an immune mechanism for the association, and finally the data showing effective treatment and recommendations for prophylactic use of anti-depressants.


Asunto(s)
Trastorno Depresivo Mayor/inmunología , Hepatitis C/psicología , Interferones/efectos adversos , Psiconeuroinmunología , Antidepresivos/uso terapéutico , Encéfalo/fisiopatología , Citocinas/sangre , Trastorno Depresivo Mayor/inducido químicamente , Trastorno Depresivo Mayor/prevención & control , Hepatitis C/tratamiento farmacológico , Hepatitis C/inmunología , Humanos , Sistema Hipotálamo-Hipofisario/fisiopatología , Interferones/uso terapéutico , Riesgo
18.
J Subst Abuse Treat ; 22(2): 55-62, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11932130

RESUMEN

Drug treatment programs are a site of opportunity for the delivery of primary and secondary hepatitis C (HCV) prevention services to drug users, a population at great risk for contracting and transmitting the virus. Using data collected from a random nationwide sample (N = 439) of drug treatment programs in the United States, this study examines the extent to which various types of HCV services are provided to their patients. Findings indicate that the majority of drug treatment programs educate at least some of their patients about HCV, and provide some type of support for patients who are infected with the virus. Only 29 of the programs in the sample test all of their patients for HCV, however, and 99 programs test none of them. For the most part, residential treatment programs offer more HCV related services than outpatient drug-free programs.


Asunto(s)
Encuestas de Atención de la Salud , Hepatitis C/prevención & control , Centros de Tratamiento de Abuso de Sustancias , Atención Ambulatoria , Consejo , Atención a la Salud/estadística & datos numéricos , Hepatitis C/etiología , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/sangre , Hospitalización , Humanos , Programas Nacionales de Salud/estadística & datos numéricos , Educación del Paciente como Asunto , Derivación y Consulta , Trastornos Relacionados con Sustancias/complicaciones , Estados Unidos
19.
Gastroenterol Clin Biol ; 24(3): 337-41, 2000 Mar.
Artículo en Francés | MEDLINE | ID: mdl-10804343

RESUMEN

OBJECTIVES: To determine the evolution of the frequency of anti-hepatitis C virus antibodies from 1992 to 1996 in blood donors and in candidates for autologous transfusion in the Alpes-Maritimes region and to assess risk factors. METHODS: Anti-hepatitis C virus antibodies were assessed by second generation ELISA in 1992 and in the first quarter of 1993, and then by third generation ELISA; in all cases, anti-hepatitis C virus antibodies were confirmed by RIBA test. RESULTS: Since 1992 (when the second generation ELISA test became available), the prevalence of anti-hepatitis C virus antibodies in blood donors in the Alpes-Maritimes region (0.54% in 1992 to 0.20% in 1996) has decreased. Positive ELISA anti-hepatitis C virus was confirmed by RIBA in 53 to 68% of anti-hepatitis C virus blood donations. The percentage of anti-hepatitis C virus donors with ALT above the upper limit (donation exclusion threshold) was between 28 and 56%.The most frequent age interval for new anti-hepatitis C virus positive donors was between 30 and 40 years. Since 1992, a third of the anti-hepatitis C virus blood donors agreed to participate in a medical history questionnaire. One or several risk factors were found in almost all donors. The most frequent source of infection was nosocomial (50%). During the 5 years of the study, the number of candidates for autologous transfusion increased: 717 in 1992 to 1 528 in 1996. The prevalence of anti-hepatitis C virus in this older population (mean age: 64 years) decreased progressively (2.9% in 1992 to 1.1% in 1996, P<0, 01) since the prevalence of anti-HBc remained stable, near 12%. Among the 96 subjects found to be anti-hepatitis C virus positive before an autologous transfusion, 49 were transfused before 1990 and 40 had a history of surgery. CONCLUSION: The prevalence of anti-hepatitis C virus has decreased since 1992 in blood donors and in candidates for autologous transfusion which may suggest that there is better screening in the general population and presenting the spread of hepatitis C virus infection.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Transfusión de Sangre Autóloga/estadística & datos numéricos , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/epidemiología , Hepatitis C/inmunología , Tamizaje Masivo/estadística & datos numéricos , Adulto , Distribución por Edad , Anciano , Alanina Transaminasa/sangre , Transfusión de Sangre Autóloga/tendencias , Ensayo de Inmunoadsorción Enzimática , Femenino , Francia/epidemiología , Hepatitis C/metabolismo , Hepatitis C/transmisión , Humanos , Masculino , Tamizaje Masivo/métodos , Tamizaje Masivo/tendencias , Persona de Mediana Edad , Factores de Riesgo , Estudios Seroepidemiológicos
20.
J Infect Dis ; 181(1): 42-50, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10608749

RESUMEN

DNA-based immunizations have been used to elicit cellular immunity to hepatitis C virus (HCV) proteins in mice. Mice were immunized by intramuscular or intradermal injections of plasmid DNA derived from a near-full-length HCV genotype 1b genomic clone (pRC/B2) or individual genomic clones. These immunizations induced cytotoxic T lymphocytes (CTLs), as revealed in standard chromium-release assays that used syngeneic peptide-pulsed or transfected target cells. These assays identified four CTL epitopes within the capsid, E1, and E2 regions of the polyprotein sequence of HCV genotype 1a that were cross-reactive with HCV genotype 1b. Additionally, CTLs derived from mice immunized with either NS3 or NS5 specifically lysed target cells sensitized to either the genotype 1a or 1b gene products. Nucleic acid immunizations also generated humoral immunity to HCV proteins, as detected by anti-HCV reactivity to NS3 and capsid in ELISAs and immunoblot assays.


Asunto(s)
Hepacivirus/inmunología , Vacunas de ADN/inmunología , Vacunas contra Hepatitis Viral/inmunología , Proteínas no Estructurales Virales/inmunología , Proteínas Estructurales Virales/inmunología , Animales , Especificidad de Anticuerpos , Secuencia de Bases , ADN Complementario/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepatitis C/inmunología , Hepatitis C/prevención & control , Anticuerpos contra la Hepatitis C/sangre , Inmunidad Celular , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Plásmidos , Vacunación
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