RESUMO
BACKGROUND & AIMS: Therapy for chronic hepatitis C (CHC) has limited efficacy, adverse effects, and high costs. Cohort and vaccine-based preclinical studies have indicated the importance of T-cell-based immunity in controlling viral infection. TG4040 is a recombinant poxvirus vaccine that expresses the hepatitis C virus (HCV) proteins NS3, NS4, and NS5B. We performed a phase I clinical trial to assess the safety, immunogenicity, and early antiviral efficacy of TG4040 in patients with CHC. METHODS: In an open-label, dose-escalating study, patients with mild CHC (genotype 1) were assigned to 3 groups of 3 patients each; they received subcutaneous injections of 106, 107, or 108 plaque-forming units of TG4040 on study days 1, 8, and 15. Six additional patients were given the highest dose of vaccine (108 plaque-forming units). Patients were followed for 6 months after the last injection. T-cell-based and antibody responses and levels of HCV RNA were measured. RESULTS: All 3 doses of TG4040 were well tolerated, without serious adverse events. Vaccine-induced HCV-specific cellular immune responses were observed in 5 of the 15 patients (33%). A transient decrease in circulating levels of HCV RNA, from -0.52 log10 to -1.24 log10, was observed in 8 patients; in 5 patients, the lowest level of HCV RNA was observed on day 37, after the first injection. The most pronounced decrease in viral load occurred in 2 patients, who also had marked vaccine-induced T-cell responses. CONCLUSIONS: In patients with CHC, the viral-vector-based vaccine TG4040 had a good safety profile, induced HCV-specific cellular immune responses, and reduced viral load. This vaccine should be investigated in further clinical studies, in combination with standard of care.
Assuntos
Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Poxviridae/imunologia , Linfócitos T/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Vacinas Virais/farmacologia , Adulto , Anticorpos Antivirais/sangue , Relação Dose-Resposta a Droga , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Linfócitos T/imunologia , Linfócitos T/patologia , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/efeitos adversos , Vacinas Virais/uso terapêuticoRESUMO
BACKGROUND: Severe neonatal jaundice resulting from elevated levels of unconjugated bilirubin in the blood induces dramatic neurological impairment. Central oxidative stress and an inflammatory response have been associated with the pathophysiological mechanism. Cells forming the blood-brain barrier and the choroidal blood-CSF barrier are the first CNS cells exposed to increased plasma levels of unconjugated bilirubin. These barriers are key regulators of brain homeostasis and require active oxidative metabolism to fulfill their protective functions. The choroid plexus-CSF system is involved in neuroinflammatory processes. In this paper, we address the impact of neonatal hyperbilirubinemia on some aspects of brain barriers. We describe physiological changes in the neurovascular network, blood-brain/CSF barriers integrities, and CSF cytokine levels during the postnatal period in normobilirubinemic animals, and analyze these parameters in parallel in Gunn rats that are deficient in bilirubin catabolism and develop postnatal hyperbilirubinemia. METHODS: Gunn rats bearing a mutation in UGT1a genes were used. The neurovascular network was analyzed by immunofluorescence stereomicroscopy. The integrity of the barriers was evaluated by [14C]-sucrose permeability measurement. CSF cytokine levels were measured by multiplex immunoassay. The choroid plexus-CSF system response to an inflammatory challenge was assessed by enumerating CSF leukocytes. RESULTS: In normobilirubinemic animals, the neurovascular network expands postnatally and displays stage-specific regional variations in its complexity. Network expansion is not affected by hyperbilirubinemia. Permeability of the blood-brain and blood-CSF barriers to sucrose decreases between one- and 9-day-old animals, and does not differ between normobilirubinemic and hyperbilirubinemic rats. Cytokine profiles differ between CSF and plasma in all 1-, 9-, and 18-day-old animals. The CSF cytokine profile in 1-day-old animals is markedly different from that established in older animals. Hyperbilirubinemia perturbs these cytokine profiles only to a very limited extent, and reduces CSF immune cell infiltration triggered by systemic exposure to a bacterial lipopeptide. CONCLUSION: The data highlight developmental specificities of the blood-brain barrier organization and of CSF cytokine content. They also indicate that a direct effect of bilirubin on the vascular system organization, brain barriers morphological integrity, and inflammatory response of the choroid plexus-CSF system is not involved in the alteration of brain functions induced by severe neonatal jaundice.
Assuntos
Barreira Hematoencefálica , Icterícia Neonatal , Animais , Bilirrubina/metabolismo , Barreira Hematoencefálica/metabolismo , Líquido Cefalorraquidiano/metabolismo , Plexo Corióideo/metabolismo , Citocinas/metabolismo , Humanos , Hiperbilirrubinemia/metabolismo , Recém-Nascido , Icterícia Neonatal/metabolismo , Ratos , Ratos Gunn , SacaroseRESUMO
BACKGROUND: Pelvic organ prolapse is common and can be detected in up to 50% of parous women although many are asymptomatic. Oestrogen preparations are used to improve vaginal thinning (atrophy). It is possible that oestrogens, alone or in conjunction with other interventions, might prevent or assist in the management of pelvic organ prolapse, for example by improving the strength of weakened supporting structures. OBJECTIVES: To determine the effects of oestrogens or drugs with oestrogenic effects alone, or in conjunction with other treatments, both for prevention and treatment of pelvic organ prolapse. SEARCH STRATEGY: We searched the Cochrane Incontinence Group Specialised Register of trials (searched 6 May 2010), MEDLINE (January 1950 to April 2010) as well as reference lists of relevant articles. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials that included the use of any oestrogens or drugs with oestrogenic (or anti-oestrogenic) actions for pelvic organ prolapse. DATA COLLECTION AND ANALYSIS: Trials were assessed and data extracted independently by two review authors. MAIN RESULTS: Three trials and one meta-analysis of adverse effects of a further three trials were identified. One trial did not provide useable data. Two trials included 148 women with prolapse, one included 58 postmenopausal women and the meta-analysis reported a mixed population (women with and without prolapse) of postmenopausal women (N=6984). The meta analysis and one other small trial investigated the effect of selective oestrogen receptor modulators (SERMs) for treatment or prevention of osteoporosis but also collected data of the effects on prolapse. Interventions included oestradiol, conjugated equine oestrogen and two (SERMs), raloxifene and tamoxifen. Only one small trial addressed the primary outcome (prolapse symptoms).One small treatment trial of oestradiol for three weeks before prolapse surgery found a reduced incidence of cystitis in the first four weeks after surgery but this unexpected finding needs to be confirmed in a larger trial.A meta-analysis of adverse effects of a SERM, raloxifene (used for treatment or prevention of osteoporosis in postmenopausal women) found a statistically significant reduction in the need for prolapse surgery at three year follow up (OR 0.50, 95% CI 0.31 to 0.81), but this was statistically significant only in women older than 60 years (OR 0.68, 95% CI 0.22 to 2.08) and the total number of women having prolapse surgery was small. A further small trial comparing conjugated equine oestrogen, raloxifene, tamoxifen and placebo in postmenopausal women having pelvic floor muscle training was too small to detect effects on prolapse outcomes. AUTHORS' CONCLUSIONS: There was limited evidence from randomised controlled trials regarding the use of oestrogens for the prevention and management of pelvic organ prolapse. The use of local oestrogen in conjunction with pelvic floor muscle training before surgery may reduce the incidence of post-operative cystitis within four weeks after surgery. Oral raloxifene may reduce the need for pelvic organ prolapse surgery in women older than 60 years although this cannot be taken as an indication for practice.There is a need for rigorous randomised controlled trials with long term follow up to assess oestrogen preparations for prevention and management of pelvic organ prolapse, particularly as an adjunctive treatment for women using pessaries and also before and after prolapse surgery.
Assuntos
Estrogênios/uso terapêutico , Prolapso de Órgão Pélvico/tratamento farmacológico , Pós-Menopausa , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Estradiol/uso terapêutico , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Humanos , Metanálise como Assunto , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/prevenção & controle , Cloridrato de Raloxifeno/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamoxifeno/uso terapêuticoRESUMO
INTRODUCTION AND HYPOTHESIS: The aim of this study is to estimate efficacy and safety of mesh in surgery for uterine or vault prolapse. METHODS: Seventeen electronic databases were searched for relevant studies that were published from 1980 onwards. RESULTS: Fifty-four studies involving 7,054 women were included. For sacrocolpopexy (average follow-up 23 months), the risk of clinical recurrence ranged from 0% to 6%, persistent symptoms ranged from 3% to 31% and mesh erosion from 0% to 12%. For infracoccygeal sacropexy (average follow-up 13 months), the risk of clinical recurrence ranged from 0% to 25%, persistent symptoms from 2% to 21% and mesh erosion 0% to 21%. Limited evidence was available for sacrocolpoperineopexy and uterine suspension sling to draw reliable estimates. CONCLUSIONS: Sacrocolpopexy was associated with a low risk of recurrence but with a relatively high risk of mesh erosion. Ranges of estimates for outcomes for other mesh techniques were wide.
Assuntos
Telas Cirúrgicas , Prolapso Uterino/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Segurança , Telas Cirúrgicas/efeitos adversosRESUMO
BACKGROUND: Recurrence of ectopic pregnancy is usually associated with assisted reproductive techniques, being less likely to occur after natural conception. CASE: We report the case of a patient who had three consecutive ectopic pregnancies on the ipsilateral side after natural conception and was treated surgically in each case with partial salpingectomy, removal of tubal stump, and resection of the uterine cornua, respectively. The contralateral normal tube was resected at the time of last operation. CONCLUSION: We indicate the high risk for tubal rupture and bleeding and the need for appropriate surgical intervention when managing recurrent ectopic pregnancies. Furthermore, care should be undertaken not to leave a long tubal stump when performing salpingectomy for ectopic pregnancy, to decrease risk of recurrence.
Assuntos
Tubas Uterinas/cirurgia , Gravidez Tubária/cirurgia , Adulto , Tubas Uterinas/patologia , Feminino , Humanos , Gravidez , Gravidez Tubária/patologia , RecidivaRESUMO
Broad immune responses, in particular specific for the NS3 protein and mediated by both CD8+ and CD4+T lymphocytes, are thought to play a critical role in the control of hepatitis C virus (HCV) infection. In this study, we searched for novel HLA-B*0702 NS3 restricted epitopes following an optimized NS3NS4 immunization protocol in transgenic mice expressing HLA-B*0702 molecule. Combining predicted and overlapping peptides, we identified two novel epitopes, WPA10 (aa 1111-1120) and LSP10 (aa 1153-1162), which triggered significant IFN-gamma-producing T cell frequencies and high CTL responses. Both epitopes were shown to be immunogenic when used as synthetic peptides to immunize mice. The relevance of these epitopes to humans was demonstrated, as both were able in vitro to recall specific IFN-gamma and IL10-producing cells from peripheral blood mononuclear cells of HCV infected patients. Such epitopes enlarge the pool of NS3-specific CD8+T cell epitopes available to perform immunomonitoring of HCV infection and to develop vaccines.
Assuntos
Antígenos HLA-B/imunologia , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Proteínas não Estruturais Virais/imunologia , Alelos , Sequência de Aminoácidos , Animais , Linfócitos T CD8-Positivos/imunologia , Sequência Conservada , Mapeamento de Epitopos , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Antígenos HLA-B/genética , Antígeno HLA-B7 , Hepacivirus/genética , Hepacivirus/crescimento & desenvolvimento , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinação , Vacinas contra Hepatite Viral/imunologia , Proteínas não Estruturais Virais/genéticaRESUMO
Endometriosis is an estrogen-dependent condition that primarily inflicts women of reproductive age. There are several gradations of the disease and its extent does not always signify its symptomatic presentation. In those women who have long suffered from endometriosis, previous treatments and their assumed success influence clinical decision making on the use of hormone replacement therapy after menopause. This review considers the management strategies for those women who have become prematurely menopausal after extensive surgical treatment for endometriosis.
Assuntos
Endometriose , Terapia de Reposição de Estrogênios , Menopausa Precoce , Feminino , Humanos , RecidivaRESUMO
The first Dominique Dormont International Conference on "Viral and host determinantsof HCV, HCMV, and HIV infections "was held in Paris, Val-de-Grâce, on December 3-4, 2004. The following is a summary of the scientific sessions of this meeting (http://www.congres-evenement.fr/ddormont).
Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Infecções por HIV/imunologia , HIV-1/patogenicidade , Hepacivirus/patogenicidade , Hepatite C Crônica/imunologia , Doença Crônica , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/fisiopatologia , Infecções por Citomegalovirus/virologia , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , HIV-1/fisiologia , Hepacivirus/fisiologia , Hepatite C Crônica/fisiopatologia , Hepatite C Crônica/virologia , HumanosRESUMO
Bleeding problems are common in perimenopausal women. They affect quality of life. Traditionally, hysterectomy was the definitive 'cure'; however, the past two decades have seen the emergence of less invasive and safer alternatives, in the form of endometrial ablation. Like hysterectomy, these treatments have a high satisfaction rate. Endometrial ablation employing resection techniques may be the procedure of choice in perimenopausal women because the majority of the endometrial cavity is sampled, which may reduce the risk of undetected endometrial cancer. Since no operation is without risk, women should be appropriately selected and counselled.
Assuntos
Hemorragia Uterina/cirurgia , Ablação por Cateter/métodos , Feminino , Humanos , Histerectomia/métodos , Perimenopausa , Hemorragia Uterina/patologiaRESUMO
OBJECTIVE: To compare menstrual status, satisfaction, and acceptability of microwave endometrial ablation with transcervical endometrial resection for the treatment of heavy menstrual bleeding. METHODS: Women were randomized to either endometrial ablative method. Menstrual status, satisfaction, acceptability, and changes in health-related quality of life were obtained by a self-completed questionnaire. Case note review and personal communication identified further surgery rates at 2 years after each procedure. RESULTS: Among the original 263 women who underwent endometrial ablation, 249 (95%) returned questionnaires at 2 years. Menstrual status in both groups was similar, although the amenorrhea rate was higher after microwave endometrial ablation. Seventy-nine percent of women were either completely or generally satisfied after microwave ablation compared with 67% after transcervical endometrial resection. Health-related quality-of-life scores remained higher than at recruitment for both treatments. Hysterectomy rates were similar at 2 years (11.6% after microwave endometrial ablation and 12.7% after transcervical endometrial resection), and no repeat endometrial ablative procedures were required. CONCLUSION: Microwave endometrial ablation is an effective alternative to transcervical endometrial resection for dysfunctional uterine bleeding.
Assuntos
Ablação por Cateter/métodos , Endométrio/cirurgia , Micro-Ondas , Hemorragia Uterina/cirurgia , Adulto , Feminino , Humanos , Satisfação do Paciente , Estudos Prospectivos , Qualidade de Vida , Inquéritos e QuestionáriosRESUMO
This retrospective case-note study was performed to examine the ways in which an already established menopause clinic could improve service to its patients. The management of 151 patients was examined. Most were referred by their general practitioner and the most common reason for referral was to seek an alternative to hormone replacement therapy (HRT). The consultant saw 17% of the patients, and with the trainee was most likely to discharge the patient. Better information on alternatives to HRT, more consultant input and better use of telephone consultation for follow-up would enhance the service provided by the menopause clinic.
Assuntos
Clínicos Gerais , Menopausa , Serviços de Saúde da Mulher/organização & administração , Feminino , Terapia de Reposição Hormonal , Humanos , Pessoa de Meia-Idade , Encaminhamento e Consulta , Estudos Retrospectivos , Escócia , Resultado do Tratamento , Reino UnidoRESUMO
Hepatitis C virus (HCV) Core has been implicated in immune-mediated mechanisms associated with the development of chronic hepatic diseases. Discovery of different alternative reading frame proteins (ARFPs) expressed from the HCV Core coding sequence challenges properties assigned to Core. This study was designed to evaluate the immunomodulatory functions of Core and ARFPs in monocytes, dendritic cells (DCs), macrophages (Mphi) and hepatocytes, cells that are all capable of supporting HCV replication. THP-1 cells, monocyte-derived Mphi and DCs, and Huh7 cells were infected by using adenoviruses (Ad) encoding Core, CE1E2 and a Core sequence modified so that the Core protein is wild type, but no ARFPs are expressed (CDeltaARFP). THP-1 cells and DCs infected with Ad encoding Core or CE1E2 produced significant levels of interleukin-6 (IL-6), IL-8, MCP-1 and MIP-1beta, whereas production of these chemokines with AdCDeltaARFP was reduced or abolished. Similar effects on IL-8 production were observed in Huh7 cells and on IL-6 and MIP-1beta in Mphi. Wild-type Core sequence, but not CDeltaARFP, could trans-activate the IL-8 promoter and this activation was not associated with activation of p38/p42-44MAPK. This study illustrates, for the first time, the critical importance of ARFP expression in immunomodulatory functions attributed to Core expression and suggests a potential involvement of ARFP in mechanisms associated with HCV pathogenesis.
Assuntos
Citocinas/biossíntese , Hepacivirus/imunologia , Proteínas do Core Viral/biossíntese , Proteínas do Core Viral/imunologia , Adenoviridae/genética , Sequência de Aminoácidos , Linhagem Celular , Células Cultivadas , Células Dendríticas/virologia , Citometria de Fluxo , Vetores Genéticos , Hepacivirus/genética , Hepatócitos/virologia , Humanos , Macrófagos/virologia , Microscopia de Fluorescência , Dados de Sequência Molecular , Monócitos/virologia , Transdução GenéticaRESUMO
OBJECTIVE: To compare long term outcomes following microwave endometrial ablation (MEA) or transcervical resection of the endometrium (TCRE). DESIGN: Follow up of a randomised controlled trial. SETTING: Gynaecology department of a large UK teaching hospital. POPULATION/SAMPLE: Two hundred and thirty-nine participants in a randomised comparison of MEA with TCRE. METHODS: Collection of patient completed postal questionnaires and operative databank review. MAIN OUTCOME MEASURES: Women's satisfaction with and acceptability of treatment, menstrual symptoms, changes in health-related quality of life and additional treatments received. RESULTS: Two hundred and thirty-six of the original 263 women returned questionnaires (90%) after a minimum of five years post-treatment. Women allocated to MEA were significantly more likely to be totally or generally satisfied with treatment (86% vs 74%; difference 12%, 95% CI 2% to 23%), to find it acceptable (97% vs 91%; difference 6%, 95% CI 1% to 13%) and would recommend it (97% vs 89%; difference 8%, 95% CI 1% to 14%). Bleeding and pain scores were highly significantly reduced following both MEA and TCRE, achieving amenorrhoea rates of 65% and 69%, respectively. The hysterectomy rate after a minimum of five years was 16% in the MEA and 25% in the TCRE arm. CONCLUSIONS: Both techniques achieve significant and comparable improvements in menstrual symptoms, and health-related quality of life. While high rates of satisfaction with treatment and acceptability of treatment are achieved by TCRE, these are significantly lower than levels following MEA. These long term data, when combined with the trials' operative findings and known costs of both procedures, now inform us that MEA is a more effective and efficient treatment for heavy menstrual loss than TCRE.
Assuntos
Ablação por Cateter/métodos , Endométrio/efeitos da radiação , Endométrio/cirurgia , Menorragia/radioterapia , Menorragia/cirurgia , Micro-Ondas/uso terapêutico , Adulto , Feminino , Seguimentos , Humanos , Satisfação do Paciente , Qualidade de Vida , Resultado do TratamentoRESUMO
Because of the lack of a robust cell culture system, relatively little is known about the molecular details of the cell entry mechanism for hepatitis C virus (HCV). Recently, we described infectious HCV pseudo-particles (HCVpp) that were generated by incorporating unmodified HCV E1E2 glycoproteins into the membrane of retroviral core particles. These initial studies, performed with E1E2 glycoproteins of genotype 1, noted that HCVpp closely mimic the cell entry and neutralization properties of parental HCV. Because sequence variations in E1 and E2 may account for differences in tropism, replication properties, neutralization, and response to treatment in patients infected with different genotypes, we investigated the functional properties of HCV envelope glycoproteins from different genotypes/subtypes. Our studies indicate that hepatocytes were preferential targets of infection in vitro, although HCV replication in extrahepatic sites has been reported in vivo. Receptor competition assays using antibodies against the CD81 ectodomain as well as ectopic expression of CD81 in CD81-deficient HepG2 cells indicated that CD81 is used by all the different genotypes/subtypes analyzed to enter the cells. However, by silencing RNA (siRNA) interference assays, our results show that the level of Scavenger Receptor Class-B Type-I (SR-BI) needed for efficient infection varies between genotypes and subtypes. Finally, sera from chronic HCV carriers were found to exhibit broadly reactive activities that inhibited HCVpp cell entry, but failed to neutralize all the different genotypes. In conclusion, we characterize common steps in the cell entry pathways of the major HCV genotypes that should provide clues for the development of cell entry inhibitors and vaccines.
Assuntos
Hepacivirus/fisiologia , Hepatócitos/virologia , Proteínas do Envelope Viral/fisiologia , Animais , Antígenos CD/fisiologia , Fenômenos Fisiológicos Sanguíneos , Antígenos CD36 , Portador Sadio/sangue , Linhagem Celular , Genótipo , Hepacivirus/genética , Hepatócitos/metabolismo , Humanos , Receptores Imunológicos/fisiologia , Receptores Depuradores , Receptores Depuradores Classe B , Tetraspanina 28 , Proteínas do Envelope Viral/metabolismo , Vírion/metabolismo , Vírion/fisiologia , Montagem de VírusRESUMO
OBJECTIVE: To formally evaluate the clinical benefit of additional outpatient hysteroscopy over traditional vaginal examination and endometrial biopsy. DESIGN: A prospective randomised controlled trial. SETTING: A large teaching hospital in the northeast of Scotland. SAMPLE Premenopausal women with abnormal uterine bleeding referred to the general gynaecologic clinic and requiring endometrial biopsy. METHODS Women were randomised to either outpatient hysteroscopy and endometrial biopsy or endometrial biopsy alone. PRIMARY OUTCOME: initial surgical intervention rates. SECONDARY OUTCOMES: procedural success and acceptability, intrauterine pathology identified and changes in management. RESULTS: Three hundred and seventy women were recruited to the study. Initial trends in clinical management were comparable in both groups. No woman was advised to have removal of a localised lesion found at outpatient hysteroscopy and a normal uterine cavity at hysteroscopy did not influence the hysterectomy rate, which was similar in both groups. Outpatient hysteroscopy was found to be as acceptable as an outpatient endometrial biopsy and successfully completed in 85% compared with 91% of women who underwent endometrial biopsy alone. No cases of endometrial malignancy were identified. CONCLUSIONS: Outpatient diagnostic hysteroscopy is an acceptable procedure and may give more reassurance. It did not influence clinical management, especially with respect to hysterectomy rate. Outpatient hysteroscopy may be useful in selected cases, but when performed in a non-selective manner, it has little influence on clinical management and increases costs.
Assuntos
Assistência Ambulatorial/métodos , Endométrio/patologia , Histeroscopia/métodos , Hemorragia Uterina/patologia , Adulto , Biópsia/efeitos adversos , Biópsia/métodos , Feminino , Humanos , Histeroscopia/efeitos adversos , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Satisfação do Paciente , Estudos Prospectivos , Hemorragia Uterina/terapiaRESUMO
Hepatitis C virus (HCV) is predominantly a hepatotropic virus. Nonetheless, there is mounting evidence that hematopoietic cells may support HCV replication. The HCV 5' untranslated region (5'UTR), responsible for initiation of viral translation, via an internal ribosome entry site (IRES), has been previously described to contain specific nucleotide substitutions when cultured in infected lymphoid cells. Our purpose was to establish whether the 5'UTR polymorphism of quasispecies from 3 cell compartments (liver, peripheral blood mononuclear cells [PBMG], and monocyte-derived dendritic cells [DCs]) of a patient chronically infected with HCV1b affects the corresponding translational efficiencies and thus the capacity for replication. The 5'UTR polymorphism was characterized by identification of changes at 3 crucial sites as compared with the reference nucleotide (nt) sequence: a G insertion between positions 19 and 20, a C>A substitution at position 204 and a G>A substitution at position 243. The quasispecies detected in DCs was unique and differed from those present in the liver, suggesting a particular tropism of HCV quasispecies for DCs. Moreover, its translational activity was significantly impaired when compared with those from liver and PBMCs in different cell lines. This impairment was thoroughly confirmed in primary cultures of both human hepatocytes and monocyte-derived DCs. Taken together, our data lend support both to a specific location and impaired replication of HCV quasispecies in DCs, which could be related to viral persistence and perturbation of DC function in chronically infected patients.
Assuntos
Células Dendríticas/virologia , Variação Genética , Hepacivirus/genética , Hepatócitos/virologia , Biossíntese de Proteínas , Regiões 5' não Traduzidas/genética , Células Sanguíneas/virologia , Feminino , Hepatite C/patologia , Hepatite C/virologia , Humanos , Pessoa de Meia-Idade , Mutação Puntual , RNA Viral/genética , Distribuição Tecidual , Células Tumorais CultivadasRESUMO
The existence of extrahepatic sites of hepatitis C virus (HCV) replication has been proposed as a mechanism responsible for the poor antiviral immune response found in chronic infection. Dendritic cells (DCs), as unique antigen-presenting cells able to induce a primary immune response, are prime targets of persistent viruses. From 24 blood samples obtained from HCV-seropositive patients, peripheral blood DCs (PBDCs) were purified. HCV genomic sequences were specifically detected by reverse-transcription polymerase chain reaction in 6 of 24 PBDC pellets, and replicative-strand RNA also was found in 3 of 24 cell purifications. Analysis of the HCV quasi-species distribution in the PBDC population of 1 patient showed the presence of a dominant variant different from that found in plasma with respect to the primary amino-acid sequence and physicochemical profile of the hypervariable region 1 of glycoprotein E2. These data strongly suggest that PBDCs constitute a reservoir in which HCV replication takes place during natural infection.
Assuntos
Células Dendríticas/virologia , Hepacivirus/fisiologia , Hepatite C Crônica/virologia , Replicação Viral , Adulto , Idoso , Sequência de Aminoácidos , Feminino , Genes Virais , Genoma Viral , Hepacivirus/química , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Alinhamento de Sequência , Especificidade da EspécieRESUMO
BACKGROUND: Plasmacytoid dendritic cells (PDCs) are the major producers of interferon (IFN)- alpha within peripheral blood mononuclear cells (PBMCs). METHODS: We analyzed whether chronic hepatitis C virus (HCV) infection could be linked to a defective function or number of PDCs. We evaluated the capacity of PBMCs from 5 cohorts of subjects to produce IFN- alpha after viral stimulation. We concomitantly analyzed the frequency of PDCs and the levels of IFN- alpha transcripts within the PBMCs from the same cohorts. RESULTS: PBMCs from patients with chronic HCV infection receiving antiviral therapy displayed a reduced capacity to release IFN- alpha, compared with those from healthy individuals, those from long-term responders to therapy, and those from nontreated patients. This defect was significantly correlated with the percentage of PDCs. In addition, PDCs from patients with chronic HCV infection receiving therapy displayed a reduced intrinsic capacity to produce IFN- alpha, which could be linked to the level of IFN- alpha transcripts. CONCLUSION: Our observations point to an effect of the therapy on either the survival or the localization of PDCs, rather than a direct detrimental effect due to the viral infection during chronic HCV infection.
Assuntos
Células Dendríticas/imunologia , Hepatite C Crônica/imunologia , Interferon-alfa/metabolismo , Leucócitos Mononucleares/citologia , Adolescente , Adulto , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Quimioterapia Combinada , Hepacivirus/imunologia , Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/uso terapêutico , Contagem de Leucócitos , Leucócitos Mononucleares/imunologia , Pessoa de Meia-Idade , Ribavirina/administração & dosagem , Ribavirina/uso terapêuticoRESUMO
In vitro studies have described the synthesis of an alternative reading frame form of the hepatitis C virus (HCV) core protein that was named F protein or ARFP (alternative reading frame protein) and includes a domain coded by the +1 open reading frame of the RNA core coding region. The expression of this protein in HCV-infected patients remains controversial. We have analyzed peripheral blood from 47 chronically or previously HCV-infected patients for the presence of T lymphocytes and antibodies specific to the ARFP. Anti-ARFP antibodies were detected in 41.6% of the patients infected with various HCV genotypes. Using a specific ARFP 99-amino-acid polypeptide as well as four ARFP predicted class I-restricted 9-mer peptides, we show that 20% of the patients display specific lymphocytes capable of producing gamma interferon, interleukin-10, or both cytokines. Patients harboring three different viral genotypes (1a, 1b, and 3) carried T lymphocytes reactive to genotype 1b-derived peptides. In longitudinal analysis of patients receiving therapy, both core and ARFP-specific T-cell- and B-cell-mediated responses were documented. The magnitude and kinetics of the HCV antigen-specific responses differed and were not linked with viremia or therapy outcome. These observations provide strong and new arguments in favor of the synthesis, during natural HCV infection, of an ARFP derived from the core sequence. Moreover, the present data provide the first demonstration of the presence of T-cell-mediated immune responses directed to this novel HCV antigen.