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1.
Nat Rev Drug Discov ; 19(3): 149-150, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127666
3.
Arch Virol ; 165(3): 583-592, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927635

RESUMO

Interferon lambda was discovered in recent years to be an antiviral agent, and research on different aspects of this antiviral factor in viral infection and investigations of its effectiveness are also progressing. The immunological effects of interferon lambda on different cell populations is not precisely known, which may be due to its use of a heterodimeric receptor consisting of IL-10R2 and IFN-λR1, which are not broadly expressed in all types of cells. In the present study, signaling by interferon lambda and its effect on the expression of hepatitis C virus (HCV) proteins were measured, and the expression pattern of some antiviral proteins and IL-10 levels were investigated in peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from 50 patients with chronic genotype 1a HCV infection and 10 healthy individuals as controls. The PBMCs were treated with various doses of interferon lambda at different times of cultivation. Real-time PCR was used for relative quantification of Mxa, PKR, OAS, ISG15 and HCV core mRNAs. Expression of the NS5A protein was measured by flow cytometry, and IL-10 production was assessed by ELISA. A significant increase in the expression of mRNA encoding antiviral proteins and a decrease in the expression of mRNAs encoding the HCV core protein were observed when cells were treated with interferon lambda in an intermittent manner. The expression of HCV NS5A protein and interleukin 10 levels were also lower than in the control group. It was shown that the maximum antiviral effect of interferon lambda in PBMCs is dependent on the dose and treatment time.


Assuntos
Hepatite C Crônica/imunologia , Interferons/farmacologia , Interleucinas/farmacologia , Leucócitos Mononucleares/imunologia , Proteínas do Core Viral/biossíntese , Proteínas não Estruturais Virais/biossíntese , Adulto , Antivirais/farmacologia , Linhagem Celular , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/imunologia , Interferon-alfa/farmacologia , Interferons/imunologia , Interleucina-10/biossíntese , Interleucinas/imunologia , Leucócitos Mononucleares/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Viral/biossíntese , Proteínas do Core Viral/genética
4.
Adv Exp Med Biol ; 1179: 17-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31741332

RESUMO

Chronic hepatitis B virus (HBV) infection remains to be a serious threat to public health and is associated with many liver diseases including chronic hepatitis B (CHB), liver cirrhosis, and hepatocellular carcinoma. Although nucleos(t)ide analogues (NA) and pegylated interferon-α (Peg-IFNα) have been confirmed to be efficient in inhibiting HBV replication, it is difficult to eradicate HBV and achieve the clinical cure of CHB. Therefore, long-term therapy has been recommended to CHB treatment under the current antiviral therapy. In this context, the new antiviral therapy targeting one or multiple critical steps of viral life cycle may be an alternative approach in future. In the last decade, the functional receptor [sodium-taurocholate cotransporting polypeptide (NTCP)] of HBV entry into hepatocytes has been discovered, and the immature nucleocapsids containing the non- or partially reverse-transcribed pregenomic RNA, the nucleocapsids containing double-strand linear DNA (dslDNA), and the empty particles devoid of any HBV nucleic acid have been found to be released into circulation, which have supplemented the life cycle of HBV. The understanding of HBV life cycle may offer a new instruction for searching the potential antiviral targets, and the new viral markers used to monitor the efficacy of antiviral therapy for CHB patients in the future.


Assuntos
Antivirais , Vírus da Hepatite B , Hepatite B Crônica , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/virologia , Hepatócitos/virologia , Humanos , Interferon-alfa/farmacologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
5.
Medicine (Baltimore) ; 98(51): e18442, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31861015

RESUMO

Genetic variation and genotype of Hepatitis B virus (HBV) are related to the efficiency of interferon alpha (IFN-α)-based antiviral therapy. However, the correlation of variation in interferon-stimulated response element (ISRE) and HBV genotype response to IFN-α therapy remains elusive.Differences of ISRE between genotype B and C HBV were explored using the HBV sequences retrieved from GenBank, and further investigated by ISRE region cloning and sequencing from 60 clinical samples post-IFN-α therapy. Additionally, ISRE mutants were constructed and their relation to responsiveness of IFN-α was evaluated by real-time PCR and Southern blot analysis.ISRE pattern between genotype B and C were found based on both clinical sample sequencing and full-length sequence alignment. The primary difference is the fourth base within the ISRE region, with T and C for genotype B and C, respectively. HBV with genotype C-type ISRE had a higher replicative capability as compared to HBV with genotype B-type ISRE after IFN-α treatment in huh7 cells. CONCLUSION:: Preference of ISRE between genotype B and C HBV are distinct. Single nucleotide difference (C to T) within the HBV ISRE region may link to the efficacy of IFN-α therapy to genotype B and C HBV. Therefore, this study provides a clue for the determination of IFN-α therapy response to HBV treatment.


Assuntos
Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Interferon-alfa/farmacologia , Elementos de Resposta , Adulto , Feminino , Genótipo , Vírus da Hepatite B/genética , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mutação , Adulto Jovem
6.
Expert Opin Drug Metab Toxicol ; 15(10): 779-785, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593639

RESUMO

Introduction: Interferon (IFN) had both antiviral and immunomodulatory effects, and was one of the approved treatments for hepatitis B virus (HBV). Herein, we reviewed the pharmacokinetics and pharmacodynamics of pegylated IFN-α (PegIFN-α) for the treatment of HBV. Areas covered: The steady-state serum levels of PegIFN-α were reached within 5 to 8 weeks, and the week 48 mean trough concentrations were approximately 2-fold higher than week 1. There was also no difference of the pharmacokinetics in male or female, healthy volunteers or patients with hepatitis B or C infection. PegIFN-α did not affect the metabolism of the cytochrome P450 (CYP) isozymes, except inhibition of CYP1A2. There was also no pharmacokinetic interaction between PegIFN-α and HBV nucleot(s)ide analogues (NUCs). Forty-eight weeks of PegIFN-α achieved 32% of HBeAg seroconversion, 32-43% of HBV DNA suppression, 41-59% of ALT normalization, and 3% of HBsAg seroconversion rate with a post-treatment durable response up to 80% in the initial responders. Expert opinion: On-treatment HBsAg titer guided the treatment of HBV with PegIFN-α. The recommendation of PegIFN-α and NUC combination or switch remained controversial. New immunotherapeutic agents are now in development. Although, PegIFN-α should continue to play a role in the treatment of HBV.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Interferon alfa-2/administração & dosagem , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Animais , Antivirais/administração & dosagem , Antivirais/farmacocinética , Antivirais/farmacologia , DNA Viral/efeitos dos fármacos , Interações de Medicamentos , Feminino , Antígenos E da Hepatite B/sangue , Humanos , Interferon alfa-2/farmacocinética , Interferon alfa-2/farmacologia , Interferon-alfa/farmacocinética , Interferon-alfa/farmacologia , Masculino , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacologia
7.
J Biosci ; 44(4)2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31502579

RESUMO

In previous studies, we found interferon-α (IFN-α) could reduce protein levels of p11, 5-hydroxytryptamine receptor 1b (5-HT1b) and 5-hydroxytryptamine receptor 4 (5-HT4), but does not influence their messenger RNA levels in SH-sy5y cells. Thus, we investigated the post-transcriptional modulation of these molecules by IFN-α. SH-sy5y cells were treated with IFN-α, NH4Cl or MG132 alone or in combination, and then the protein levels of p11, 5-HT1b and 5-HT4 were analyzed by western blots. The regulatory effects of p11 on 5-HT1b and 5-HT4 were also determined in p11 knock-down cells. NH4Cl but not MG132 could reverse the protein level of p11 in IFN-α-treated SH-sy5y cells. MG132 could recover the protein levels of 5-HT1b and 5-HT4 in p11 knock-down cells. The down-regulation effects of IFN-α on p11, 5-HT1b and 5-HT4 were associated with the lysosome and ubiquitin-proteasome-mediated pathways. p11 was identified as a potent regulator to modulate the ubiquitination of 5-HT1b and 5-HT4. Therefore, it could be potential target therapies in IFN-ainduced depression.


Assuntos
Depressão/tratamento farmacológico , Interferon-alfa/farmacologia , Receptor 5-HT1B de Serotonina/genética , Cloreto de Amônio/farmacologia , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/genética , Depressão/genética , Depressão/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Leupeptinas/farmacologia , Lisossomos/efeitos dos fármacos , Lisossomos/genética , Proteólise , RNA Mensageiro/genética , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ubiquitina
8.
Acta Virol ; 63(3): 261-269, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507191

RESUMO

Bovine viral diarrhea virus (BVDV) exists in two main biotypes: cytopathic (cp) and noncytopathic (ncp). Although some studies were done on the effect of interferon alpha (IFN-α) on BVDV, the effect of exogenous IFN against BVDV biotypes remains unclear. In the present study, we evaluated the comparative effect of exogenous human IFN-α (HuIFN-α) on different BVDV biotypes and genotypes. The results showed that exogenous HuIFN-α greatly inhibited the growth of different BVDV biotypes and genotypes. However, HuINF-α has a significant inhibitory effect on cp biotype compared to ncp one without significant variation between different genotypes. The effect of HuIFN-α on BVDV reached the maximum level at early stages of infection (0-20 h post infection) and increased in a dose-dependent manner (10-500 U/ml). Quantitative real-time RT-PCR was used to evaluate the effect of exogenous HuIFN-α on RNA synthesis of both BVDV biotypes. HuIFN-α reduced RNA production of cp by 4 logs compared to only 2 logs for ncp strains. Additionally, the antiviral effect of IFN-α against both BVDV biotypes seems to be independent of the RNA-dependent protein kinase (PKR) activation as assayed by direct analysis of in vivo phosphorylation of eIF2-α and by 2-aminopurine (2-AP) treatment. Collectively, these results indicated that the exogenous HuIFN-α treatment has an inhibitory effect not only on cp BVDV biotype but also on the ncp BVDV. The antiviral effect of exogenous HuIFN-α was biotype, time, dose but not genotype dependent. PKR has no role in the inhibitory effect suggesting that other IFN-antiviral pathways were involved. Keywords: BVDV biotypes; HuIFN-α; RNA synthesis; PKR-independent.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Vírus da Diarreia Viral Bovina , Interferon-alfa , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/tratamento farmacológico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Replicação Viral/efeitos dos fármacos
9.
World J Gastroenterol ; 25(32): 4580-4597, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31528088

RESUMO

Chronic delta hepatitis is the most severe form of viral hepatitis affecting nearly 65 million people worldwide. Individuals with this devastating illness are at higher risk for developing cirrhosis and hepatocellular carcinoma. Delta virus is a defective RNA virus that requires hepatitis B surface antigen for propagation in humans. Infection can occur in the form of a co-infection with hepatitis B, which can be self-limiting, vs superinfection in a patient with established hepatitis B infection, which often leads to chronicity in majority of cases. Current noninvasive tools to assess for advanced liver disease have limited utility in delta hepatitis. Guidelines recommend treatment with pegylated interferon, but this is limited to patients with compensated disease and is efficacious in about 30% of those treated. Due to limited treatment options, novel agents are being investigated and include entry, assembly and export inhibitors of viral particles in addition to stimulators of the host immune response. Future clinical trials should take into consideration the interaction of hepatitis B and hepatitis D as suppression of one virus can lead to the activation of the other. Also, surrogate markers of treatment efficacy have been proposed.


Assuntos
Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Hepatite B Crônica/tratamento farmacológico , Hepatite D Crônica/tratamento farmacológico , Superinfecção/tratamento farmacológico , Terapias em Estudo/métodos , Antivirais/farmacologia , Coinfecção/epidemiologia , Coinfecção/virologia , Quimioterapia Combinada/métodos , Carga Global da Doença , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Hepatite D Crônica/epidemiologia , Hepatite D Crônica/virologia , Vírus Delta da Hepatite/imunologia , Vírus Delta da Hepatite/patogenicidade , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Transportadores de Ânions Orgânicos Dependentes de Sódio/antagonistas & inibidores , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Literatura de Revisão como Assunto , Superinfecção/epidemiologia , Superinfecção/virologia , Simportadores/antagonistas & inibidores , Simportadores/metabolismo , Resultado do Tratamento , Montagem de Vírus/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos
10.
PLoS Pathog ; 15(9): e1008011, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498845

RESUMO

Identification and characterization of CD8+ and CD4+ T-cell epitopes elicited by HIV therapeutic vaccination is key for elucidating the nature of protective cellular responses and mechanism of the immune evasion of HIV. Here, we report the characterization of HIV-specific T-cell responses in cART (combination antiretroviral therapy) treated HIV-1 infected patients after vaccination with ex vivo-generated IFNα Dendritic Cells (DCs) loaded with LIPO-5 (HIV-1 Nef 66-97, Nef 116-145, Gag 17-35, Gag 253-284 and Pol 325-355 lipopeptides). Vaccination induced and/or expanded HIV-specific CD8+ T cells producing IFNγ, perforin, granzyme A and granzyme B, and also CD4+ T cells secreting IFNγ, IL-2 and IL-13. These responses were directed against dominant and subdominant epitopes representing all vaccine regions; Gag, Pol and Nef. Interestingly, IL-2 and IL-13 produced by CD4+ T cells were negatively correlated with the peak of viral replication following analytic treatment interruption (ATI). Epitope mapping confirmed that vaccination elicited responses against predicted T-cell epitopes, but also allowed to identify a set of 8 new HIV-1 HLA-DR-restricted CD4+ T-cell epitopes. These results may help to better design future DC therapeutic vaccines and underscore the role of vaccine-elicited CD4+ T-cell responses to achieve control of HIV replication.


Assuntos
Vacinas contra a AIDS/imunologia , Epitopos de Linfócito T/imunologia , Vacinas contra a AIDS/metabolismo , Adulto , Antirretrovirais , Antivirais/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Quimioterapia Combinada/métodos , Epitopos/imunologia , Feminino , Infecções por HIV/imunologia , HIV-1/imunologia , HIV-1/patogenicidade , Humanos , Interferon-alfa/metabolismo , Interferon-alfa/farmacologia , Masculino , Pessoa de Meia-Idade , Vacinação
11.
Vet Microbiol ; 236: 108395, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31500730

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically significant pathogen that has been recognized for its genetic variation, rapid evolution, and immune suppression. Type I interferons (IFNs) play an important role in host defense against viral infection by inducing many antiviral effectors, which might be a selective pressure driving viral evolution towards IFN resistance. To investigate the IFN resistance-related variation of PRRSV genome under IFN selective pressure and explore the molecular mechanism of IFN sensitivity changes, PRRSV strain JXwn06 was serially propagated in porcine pulmonary alveolar macrophages (PAMs) with IFNα treatment for 45 passages and 3 rounds of purification. Four mutant strains named JX-αP51n (n = 1, 2, 3 and 4) with reduced IFNα sensitivity were selected; the strains showed a 100-fold higher titer than the passaging-control strain JX-P51 in IFNα-treated PAMs. IFNα-resistant strains were found to antagonize the IFNα-activated JAK-STAT signaling pathway to a greater extent than the nonresistant strain by down-regulating the expression level of IFNα-activated pJAK1 through interfering with phosphatase. Furthermore, the PRRSV genetic variations interacting with IFNα were identified by full genomic sequencing and alignment. Among these mutations, amino acid substitutions in nsp1ß (E87 G), GP3 (F143 L) and GP5 (Y136 H) were found to correlate with increased IFNα resistance by enhancing the suppression effect on pJAK1, which could be further increased if these three substitution sites were combined. These findings provide some novel evidence for understanding PRRSV genetic variation under host selective pressure and viral evolution strategies to evade the host innate immune response.


Assuntos
Farmacorresistência Viral/genética , Interferon-alfa/farmacologia , Mutação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Regulação da Expressão Gênica , Haplorrinos , Fosforilação , Vírus da Síndrome Respiratória e Reprodutiva Suína/efeitos dos fármacos , RNA Viral , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/genética , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais , Suínos , Proteínas Virais/genética
12.
PLoS Pathog ; 15(8): e1007949, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31374104

RESUMO

Host encounters with viruses lead to an innate immune response that must be rapid and broadly targeted but also tightly regulated to avoid the detrimental effects of unregulated interferon expression. Viral stimulation of host negative regulatory mechanisms is an alternate method of suppressing the host innate immune response. We examined three key mediators of the innate immune response: NF-KB, STAT1 and STAT2 during HCV infection in order to investigate the paradoxical induction of an innate immune response by HCV despite a multitude of mechanisms combating the host response. During infection, we find that all three are repressed only in HCV infected cells but not in uninfected bystander cells, both in vivo in chimeric mouse livers and in cultured Huh7.5 cells after IFNα treatment. We show here that HCV and Flaviviruses suppress the innate immune response by upregulation of PDLIM2, independent of the host interferon response. We show PDLIM2 is an E3 ubiquitin ligase that also acts to stimulate nuclear degradation of STAT2. Interferon dependent relocalization of STAT1/2 to the nucleus leads to PDLIM2 ubiquitination of STAT2 but not STAT1 and the proteasome-dependent degradation of STAT2, predominantly within the nucleus. CRISPR/Cas9 knockout of PDLIM2 results in increased levels of STAT2 following IFNα treatment, retention of STAT2 within the nucleus of HCV infected cells after IFNα stimulation, increased interferon response, and increased resistance to infection by several flaviviruses, indicating that PDLIM2 is a global regulator of the interferon response.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Infecções por Flavivirus/imunologia , Flavivirus/imunologia , Hepacivirus/imunologia , Hepatite C/imunologia , Imunidade Inata/imunologia , Proteínas com Domínio LIM/fisiologia , Fator de Transcrição STAT2/metabolismo , Animais , Antivirais/farmacologia , Flavivirus/efeitos dos fármacos , Infecções por Flavivirus/tratamento farmacológico , Infecções por Flavivirus/virologia , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Imunidade Inata/efeitos dos fármacos , Interferon-alfa/farmacologia , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , NF-kappa B , Fator de Transcrição STAT2/genética , Transdução de Sinais
13.
Medicine (Baltimore) ; 98(32): e16683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393369

RESUMO

Interferon-alpha (IFN-α) is currently the preferred antiviral treatment for children with chronic hepatitis B (CHB) aged >1-year-old. However, the evidence regarding the exact efficacy and safety in the real world is not sufficient. This study aimed to investigate the efficacy of IFN-α therapy in children with CHB and to provide a theoretical basis for practically identifying ideal antiviral therapies for CHB children.Clinical manifestations, baseline characteristics, related laboratory tests, and adverse events were retrospectively analyzed in children with CHB who visited the Children's Hospital of Fudan University, were treated with IFN-α and were followed up from January 2003 to October 2018.A total of 18 immune-active patients without advanced fibrosis were enrolled, and their average age at the start of treatment was 4.45 ±â€Š2.75 years old. IFN α-2b was administered subcutaneously by body surface area (BSA) category, based on 3 MU/m, for a median 48 weeks. Before treatment, the alanine aminotransferase (ALT) range was 81 to 409 U/L (median 158 U/L). The median hepatitis B virus (HBV)-DNA load was 9.89 × 10 IU/mL, and the HBV-DNA load varied from 3.10 × 10 to 4.56 × 10 IU/mL. The ALT levels of 17 children became normal at an average of 12 weeks during treatment, and those of 1 child became normal at 6 weeks after IFN-α withdrawal. Sixteen (88.9%, 16/18) children became HBV-DNA negative (<10 IU/mL) at an average of 24 weeks during treatment, while 1 became negative at 96 weeks after IFN-α withdrawal and 1 remained HBV-DNA positive. HBV e antigen (HBeAg) seroconversion occurred in 13 of 14 (92.9%, 13/14) HBeAg-positive patients at an average of 12 weeks during treatment. HBV s antigen (HBsAg) loss or seroconversion occurred in 4 (22.2%, 4/18) patients at an average of 21 weeks during treatment. Only mild flu-like symptoms and transient neutropenia appeared in some children at the early treatment stage. No severe abnormal results were observed in other laboratory parameters.The antiviral monotherapy of 48 weeks of IFN-α was well tolerated and good responded, which was associated with higher rates of HBeAg seroconversion and HBsAg clearance in the children in this study than in previously reported adults and pediatric patients.


Assuntos
Antivirais/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Adolescente , Antivirais/farmacologia , Criança , Pré-Escolar , China , Estudos de Coortes , Feminino , Seguimentos , Humanos , Injeções Subcutâneas , Interferon-alfa/farmacologia , Masculino , Soroconversão/efeitos dos fármacos , Carga Viral/efeitos dos fármacos
14.
PLoS One ; 14(6): e0216139, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31188831

RESUMO

Oral administration of nucleotide analogues and injection of interferon-α (IFNα) are used to achieve immediate suppression in replication of hepatitis B virus (HBV). Nucleotide analogs and IFNα inhibit viral polymerase activity and cause long-term eradication of the virus at least in part through removing covalently closed circular DNA (cccDNA) via induction of the APOBEC3 deaminases family of molecules, respectively. This study aimed to explore whether the orally administrable low molecular weight agent CDM-3008 (RO8191), which mimics IFNα through the binding to IFNα/ß receptor 2 (IFNAR2) and the activation of the JAK/STAT pathway, can suppress HBV replication and reduce cccDNA levels. In primary cultured human hepatocytes, HBV DNA levels were decreased after CDM-3008-treatment in a dose-dependent manner with a half-maximal inhibitory concentration (IC50) value of 0.1 µM, and this was accompanied by significant reductions in cellular cccDNA levels, both HBeAg and HBsAg levels in the cell culture medium. Using a microarray we comprehensively analyzed and compared changes in gene (mRNA) expression in CDM-3008- and IFNα-treated primary cultured human hepatocytes. As reported previously, CDM-3008 mimicked the induction of genes that participate in the interferon signaling pathway. OAS1 and ISG20 mRNA expression was similarly enhanced by both CDM-3008 and IFNα. Thus, CDM-3008 could suppress pgRNA expression to show anti-HBV activity. APOBEC3F and 3G mRNA expression was also induced by CDM-3008 and IFNα treatments, suggesting that cccDNA could be degraded through induced APOBEC3 family proteins. We identified the genes whose expression was specifically enhanced in CDM-3008-treated cells compared to IFNα-treated cells. The expression of SOCS1, SOCS2, SOCS3, and CISH, which inhibit STAT activation, was enhanced in CDM-3008-treated cells suggesting that a feedback inhibition of the JAK/STAT pathway was enhanced in CDM-3008-treated cells compared to IFNα-treated cells. In addition, CDM-3008 showed an additive effect with a clinically-used nucleoside entecavir on inhibition of HBV replication. In summary, CDM-3008 showed anti-HBV activity through activation of the JAK/STAT pathway, inducing the expression of interferon-stimulated genes (ISGs), with greater feedback inhibition than IFNα.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Interferon-alfa/farmacologia , Naftiridinas/farmacologia , Oxidiazóis/farmacologia , Antivirais/farmacologia , Células Cultivadas , DNA Viral/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatócitos/citologia , Hepatócitos/virologia , Humanos , Mimetismo Molecular , Proteínas Tirosina Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo , Replicação Viral/efeitos dos fármacos
15.
Nat Microbiol ; 4(9): 1558-1570, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31160823

RESUMO

Several Ebola viruses cause outbreaks of lethal haemorrhagic fever in humans, but developing therapies tackle only Zaire Ebola virus. Dendritic cells (DCs) are targets of this infection in vivo. Here, we found that Ebola virus entry into activated DCs requires the sialic acid-binding Ig-like lectin 1 (Siglec-1/CD169), which recognizes sialylated gangliosides anchored to viral membranes. Blockage of the Siglec-1 receptor by anti-Siglec-1 monoclonal antibodies halted Ebola viral uptake and cytoplasmic entry, offering cross-protection against other ganglioside-containing viruses such as human immunodeficiency virus type 1.


Assuntos
Anticorpos Monoclonais/farmacologia , Citoplasma/virologia , Ebolavirus/fisiologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/antagonistas & inibidores , Ligação Viral/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Gangliosídeos/metabolismo , HIV-1/fisiologia , Doença pelo Vírus Ebola/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Interferon-alfa/farmacologia , Lipopolissacarídeos/farmacologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Vírion/metabolismo
16.
Med Sci Monit ; 25: 4665-4674, 2019 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-31230063

RESUMO

BACKGROUND High rates of HBeAg and/or HBsAg seroconversion or clearance have been achieved in chronic hepatitis B (CHB) patients receiving pegylated interferon (pegIFN) in addition to ongoing nucleos(t)ide analogue (NUC) treatment. In the present study, we aimed to evaluate HBsAg kinetics to predict HBeAg seroconversion and HBsAg clearance in these patients. MATERIAL AND METHODS A total of 33 HBeAg-positive and 17 HBeAg-negative patients were enrolled between January 2010 and January 2018. At the end of pegIFN treatment, 9 of 50 patients achieved HBsAg clearance, and 9 of 33 HBeAg-positive patients achieved HBeAg seroconversion. RESULTS The cutoff value of 0.41 log10 IU/mL in HBsAg decline at week 12 had a positive predictive value (PPV) of 58.3% and a negative predictive value (NPV) of 94.6% for HBsAg clearance. The cutoff value of 1.94 log10 IU/mL in HBsAg decline at week 24 had a PPV of 80.0% and an NPV of 97.5% for HBsAg clearance. The cutoff value of 0.47 log10 IU/mL in HBsAg decline at week 12 had a PPV of 83.3% and an NPV of 85.2% for HBeAg seroconversion. The cutoff value of 1.29 log10 IU/mL in in HBsAg decline at week 24 had a PPV of 85.7% and an NPV of 88.5% for HBeAg seroconversion. CONCLUSIONS Early HBsAg drop has a high predictive value for HBsAg clearance and HBeAg seroconversion in patients who were treated with combination therapy of pegIFN and NUCs.


Assuntos
Antígenos de Superfície da Hepatite B/análise , Hepatite B Crônica/tratamento farmacológico , Adulto , Antivirais/uso terapêutico , Biomarcadores Farmacológicos/sangue , DNA Viral/sangue , Feminino , Guanina/análogos & derivados , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/sangue , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Humanos , Interferon alfa-2/farmacocinética , Interferon alfa-2/farmacologia , Interferon-alfa/farmacologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/farmacologia , Proteínas Recombinantes/farmacologia , Soroconversão , Resultado do Tratamento
17.
Nat Microbiol ; 4(9): 1532-1544, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31133753

RESUMO

RNA-modulating factors not only regulate multiple steps of cellular RNA metabolism, but also emerge as key effectors of the immune response against invading viral pathogens including human immunodeficiency virus type-1 (HIV-1). However, the cellular RNA-binding proteins involved in the establishment and maintenance of latent HIV-1 reservoirs have not been extensively studied. Here, we screened a panel of 62 cellular RNA-binding proteins and identified NEDD4-binding protein 1 (N4BP1) as a potent interferon-inducible inhibitor of HIV-1 in primary T cells and macrophages. N4BP1 harbours a prototypical PilT N terminus-like RNase domain and inhibits HIV-1 replication by interacting with and degrading viral mRNA species. Following activation of CD4+ T cells, however, N4BP1 undergoes rapid cleavage at Arg 509 by the paracaspase named mucosa-associated lymphoid tissue lymphoma translocation 1 (MALT1). Mutational analyses and knockout studies revealed that MALT1-mediated inactivation of N4BP1 facilitates the reactivation of latent HIV-1 proviruses. Taken together, our findings demonstrate that the RNase N4BP1 is an efficient restriction factor of HIV-1 and suggest that inactivation of N4BP1 by induction of MALT1 activation might facilitate elimination of latent HIV-1 reservoirs.


Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ativação Viral/genética , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Infecções por HIV/metabolismo , Humanos , Interferon-alfa/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/virologia , Camundongos , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Domínios Proteicos , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Latência Viral
18.
Prep Biochem Biotechnol ; 49(8): 735-743, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31135267

RESUMO

Type I interferons (IFNs) are homologous cytokines that bind to a cell surface receptor and establish signaling pathways that motivate immune responses. The purpose of the current study is to assess the activity of a novel-engineered IFN-α2b. The crystallographic structure of IFN-α2b and its receptors was acquired from Protein Data Bank. Various amino acid substitutions were designed based on structural properties and other biological characteristics of residues to find the most effective amino acid on IFN affinity to advanced activities. The IFN-α2b mutants and receptors have been modeled and the interactions between two proteins have been studied as in silico by protein-protein docking for both mutants and native forms. The proper nucleic acid sequence IFN-α2 (T79Q) has been prepared based on the selected mutant. The modified IFN gene was cloned in pcDNA 3.1(-) and introduced to Chinese Hamster Ovary (CHO) cell line. Antiviral and antiproliferative assays of native and IFN-α2 (T79Q) proteins were performed in vitro. The results showed two-fold increasing in IFN-α2 (T79Q) activity (antiviral and antiproliferative activity) in comparison to native IFN-α2b. This engineered IFN-α2b may have significant novel therapeutic applications and in silico studies can be an influential method for practical research function and structure of these molecules.


Assuntos
Substituição de Aminoácidos , Interferon-alfa/genética , Interferon-alfa/metabolismo , Engenharia de Proteínas , Receptores de Interferon/metabolismo , Animais , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Células CHO , Proliferação de Células/efeitos dos fármacos , Cricetulus , Células HeLa , Humanos , Interferon-alfa/química , Interferon-alfa/farmacologia , Simulação de Acoplamento Molecular , Conformação Proteica , Engenharia de Proteínas/métodos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia
19.
Vet Microbiol ; 231: 139-146, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955801

RESUMO

The recent emergence of highly pathogenic porcine reproductive and respiratory syndrome virus 1 (PRRSV-1) strains has caused severe economic losses. The biological elements defining virulence and pathogenicity are still unclear. In vitro characteristics using natural target cells of PRRSV provide important information to understand the basis of virulence at the cellular level, and provide a mean to reduce animal experimentations to achieve this goal. Here, we compared PRRSV strains from two geographically different regions, with varying in vivo characteristics, in terms of their interactions with monocyte-derived macrophages (MDMs). The strains included Lena and BOR59 from Belarus, and ILI6 from Russia, as well as PR11 and PR40, both from Italy. As a reference, we used a cell culture-adapted version of Lelystad, LVP. MDMs were pre-treated with IFNγ, IL-4 or IFNß, in order to understand responses in polarized and antiviral MDMs. In general, independent of the geographical origin, the strains with high virulence infected a higher percentage of MDMs and replicated to higher titers. These virulence-dependent differences were most pronounced when the MDMs had been treated with IFNß. Differentiation between intermediate and low virulent PRRSV was difficult, due to variations between different experiments, but LVP differed clearly from all field strains. IFNα and IL-10 were not detected in any experiment, but PR40 induced TNF and IL-1ß. Taken together, these results validate the MDM model to understand pathogenicity factors of PRRSV and confirm the importance of the escape from type I and II IFN-mediated effects for PRRSV virulence.


Assuntos
Macrófagos/virologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Animais , Interferon-alfa/farmacologia , Interferon beta/farmacologia , Interleucina-10/farmacologia , Itália , Macrófagos/efeitos dos fármacos , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , República de Belarus , Federação Russa , Suínos , Virulência
20.
Cancer Lett ; 451: 34-47, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30862487

RESUMO

Despite multiple antitumor activities, interferon-alpha (IFNα) therapy alone is less effective in solid tumors. Autophagy has been reported to play a key role in tumor chemoresistance. Therefore, it is meaningful to explore whether autophagy can be activated by IFNα in head and neck squamous cell carcinoma (HNSCC) and serve as a potential target to improve efficacy of IFNα therapy. In this study, we report that IFNα not only exhibits anti-proliferation activity and induces apoptosis, but also activates autophagy in HNSCC cells. Moreover, silencing autophagy-related protein 5 (ATG5) and signal transducer and activator of transcription 1 (STAT1) suppresses autophagy flux. Furthermore, IFNα and autophagy inhibitors (hydroxychloroquine and wortmannin) show clear synergistic effects on inhibiting growth and promoting apoptosis in HNSCC cells and xenograft models. Our findings indicate that IFNα-induced autophagy plays a cytoprotective role and blocking autophagy flux promotes IFNα-mediated apoptosis in HNSCC. These results suggest that the combination of IFNα and autophagy inhibitors represents a novel strategy for HNSCC treatment.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/patologia , Interferon-alfa/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Proteína 5 Relacionada à Autofagia/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fator de Transcrição STAT1/metabolismo
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