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1.
Yale J Biol Med ; 93(2): 277-281, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32607088

RESUMO

Oral herpes labialis, more commonly known as cold sores, are a common encountered viral infection involving herpes simplex virus-1 (HSV-1). Although relatively benign, these lesions can be both unsightly and clinically difficult to manage. Prescription standards of care and over-the-counter agents, such as docosonal, have often shown only limited efficacy in both decreasing lesional pain and reducing duration of lesional symptomology and are not without potential side effects. Despite some success with acute remediation, recurrent episodes often occur, with seemingly no imparted protection or suppression against future outbreaks. This case report involves the successful treatment of oro-facial herpes labialis with a synergistic botanical blend with marked reduction in symptoms, pain score, and lesion duration. Monitoring and evaluation post-treatment and application during future prodromal symptoms was also performed demonstrating additional reduction in the frequency of subsequent outbreaks. This case report supports the use of this treatment for prodromal and acute treatment of oro-facial herpes infection and appears to impart a reduction in the frequency of future outbreaks.


Assuntos
Eleutherococcus , Glycyrrhiza , Herpes Labial , Hypericum , Lavandula , Melissa , Sarraceniaceae , Cicatrização/efeitos dos fármacos , Adulto , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Antivirais/farmacologia , Composição de Medicamentos , Feminino , Géis/farmacologia , Herpes Labial/diagnóstico , Herpes Labial/fisiopatologia , Herpes Labial/terapia , Humanos , Prevenção Secundária/métodos , Simplexvirus/efeitos dos fármacos , Resultado do Tratamento
2.
Altern Ther Health Med ; 24(4): 56-60, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29101773

RESUMO

Intravenous glutathione has been suggested empirically to improve Parkinson's disease (PD) symptoms of tremor and rigidity, but there is limited supporting research. This case report demonstrates both subjective and objective symptom improvement of a conventionally-treated patient suffering from PD when adjunctive intravenous glutathione was administered. In addition to suggesting clinical benefit, this case also suggests an effective therapeutic frequency of therapy and a minimal therapeutic dose. The consistent pattern of improvement following glutathione injections asserts that this therapy may improve symptoms common to PD patients and can offer additional quality of life that would be otherwise unattainable to these patients.


Assuntos
Glutationa/administração & dosagem , Rigidez Muscular/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Tremor/tratamento farmacológico , Administração Intravenosa , Glutationa/uso terapêutico , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Qualidade de Vida , Resultado do Tratamento
3.
Altern Ther Health Med ; 24(1): 56-60, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29101774

RESUMO

Context • Shoulder pain is one of the most common pain complaints reported by patients. Consensus is lacking on its ideal treatment, and many different treatments are available and used. Prolotherapy is an injection-based therapy that has shown significant results in treating many common musculoskeletal pain conditions, including osteoarthritis, lateral epicondylosis, and low-back pain. Objective • The study intended to evaluate the use of dextrose prolotherapy in the treatment of shoulder pain. Design • The research team performed a case study. Setting • The study occurred at the Medical Center at Southwest College of Naturopathic Medicine (Tempe, AZ, USA). Participant • The participant was a middle-aged male with a long-term history of untreated shoulder pain. Intervention • Injections were placed in the patient's glenohumeral joint space, the acromioclavicular joint, the subacromial space, and the insertion of the supraspinatus. Each location was injected with a solution of 50% dextrose diluted with 1% lidocaine, 0.25% bupivacaine, and 1 mg methylcobalamin. The final concentration of dextrose in the solution was approximately 22.8%. Outcome Measures • The patient completed questionnaires (numerical rating scale, verbally reported at the beginning of each visit) indicating his level of pain on a scale of 0 to 10, with 0 = no pain and 10 = worst pain. Results • Following 3 sessions of prolotherapy, the patient reported a 90% reduction in pain and full restoration of normal activity. Conclusions • The findings suggest that dextrose prolotherapy may be an effective treatment for chronic shoulder pain and may be an alternative to surgery or other more costly and invasive interventions.


Assuntos
Glucose/uso terapêutico , Proloterapia , Dor de Ombro/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor
4.
Virology ; 511: 290-299, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28919326

RESUMO

Ambystoma tigrinum virus (ATV) (family Iridoviridae, genus Ranavirus) was isolated from diseased tiger salamanders (Ambystoma tigrinum stebbinsi) from the San Rafael Valley in southern Arizona, USA in 1996. Genomic sequencing of ATV, as well as other members of the genus, identified an open reading frame that has homology to the eukaryotic translation initiation factor, eIF2α (ATV eIF2α homologue, vIF2αH). Therefore, we asked if the ATV vIF2αH could also inhibit PKR. To test this hypothesis, the ATV vIF2αH was cloned into vaccinia virus (VACV) in place of the well-characterized VACV PKR inhibitor, E3L. Recombinant VACV expressing ATV vIF2αH partially rescued deletion of the VACV E3L gene. Rescue coincided with rapid degradation of PKR in infected cells. These data suggest that the salamander virus, ATV, contains a novel gene that may counteract host defenses, and this gene product may be involved in the presentation of disease caused by this environmentally important pathogen.


Assuntos
Inibidores de Proteínas Quinases/metabolismo , Ranavirus/patogenicidade , Proteínas Recombinantes/metabolismo , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismo , eIF-2 Quinase/antagonistas & inibidores , Ambystoma/virologia , Animais , Arizona , Expressão Gênica , Vetores Genéticos , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Ranavirus/genética , Proteínas Recombinantes/genética , Vaccinia virus/genética , Proteínas Virais/genética , Fatores de Virulência/genética
5.
Altern Ther Health Med ; 23(3): 51-54, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28236614

RESUMO

Context • Viral plantar warts, or verruca plantaris, are a benign epithelial tumor caused by various strains of the human papilloma virus (HPV). Current treatments have had mixed degrees of success, are moderately invasive, and are often incompatible with participation in sports. Objective • The study intended to examine the benefits of treating plantar warts with a topical, botanical blend that has had clinical success treating herpes simplex virus cold sores. Methods • A synergistic botanical blend was applied topically. Setting • The case report was completed at the Southwest College of Naturopathic Medicine (Tempe, Arizona, USA). Participant • The participant was a 24-y-old male soccer player, 177.8 cm tall, and weighing 69 kg with previously diagnosed, viral mosaic warts. Intervention • The patient used a pumice stone during bathing for the first week to remove dead tissue and ensure sufficient contact and entry of the botanical gel into infected tissue. After drying the area, the patient applied the botanical gel blend 1 to 2 times daily postshower, spreading it evenly across the surface of the entire lesion. The patient discontinued the exfoliation technique after the first week. Results • Within the first week of treatment, the patient noted changes to the infected area of the hallux epidermal tissue. The combination of exfoliation and application of the gel caused marked, visible differences in presentation by the fifth day of treatment. At 1-mo postintervention, or day 90, the epidermal tissue was asymptomatic and devoid of petechiae, malformations, or visible infection. Conclusions • The results of the current case study directly contrast with the drawbacks of commonly accepted, first-line interventions in the treatment of viral plantar warts and, in many respects, demonstrate better efficacy and fewer side effects than the standard of care. The positive results also highlight the necessity for additional study in the fields of sports medicine and podiatry to further establish the botanical blend when treating viral plantar in athletes, an overall at-risk population for the condition.


Assuntos
Pé/patologia , Preparações de Plantas/uso terapêutico , Verrugas/tratamento farmacológico , Verrugas/patologia , Adulto , Humanos , Masculino , Fitoterapia , Preparações de Plantas/administração & dosagem , Futebol , Adulto Jovem
6.
PLoS One ; 11(7): e0159857, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27458926

RESUMO

The use of botanical medicine by practitioners and the general public has dramatically increased in recent years. Most of these botanical therapeutics are obtained through commercial manufacturers or nutraceutical companies. The current standard of practice that manufacturers typically use to standardize botanicals is done based on the level of a well-known, abundant marker compound present in the botanical. This study evaluated the putative correlation between the level of a marker compound and the biological activity of eight common botanicals. Overall, the standardization of a botanical based on a marker compound was found not to be a reliable method when compared to in vitro bioactivity. A marker compound is often not the biologically active component of a plant and therefore the level of such a marker compound does not necessarily correlate with biological activity or therapeutic efficacy.


Assuntos
Anti-Infecciosos/normas , Preparações de Plantas/normas , Animais , Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Herpesvirus Humano 1/efeitos dos fármacos , Humanos , Preparações de Plantas/farmacologia , Valores de Referência , Staphylococcus aureus/efeitos dos fármacos , Células Vero
7.
PLoS One ; 7(3): e32610, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22427855

RESUMO

In the nineteenth century, smallpox ravaged through the United States and Canada. At this time, a botanical preparation, derived from the carnivorous plant Sarracenia purpurea, was proclaimed as being a successful therapy for smallpox infections. The work described characterizes the antipoxvirus activity associated with this botanical extract against vaccinia virus, monkeypox virus and variola virus, the causative agent of smallpox. Our work demonstrates the in vitro characterization of Sarracenia purpurea as the first effective inhibitor of poxvirus replication at the level of early viral transcription. With the renewed threat of poxvirus-related infections, our results indicate Sarracenia purpurea may act as another defensive measure against Orthopoxvirus infections.


Assuntos
Fitoterapia/história , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Sarraceniaceae/química , Varíola/tratamento farmacológico , Vírus da Varíola/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Canadá , Linhagem Celular , Cidofovir , Citosina/análogos & derivados , Citosina/uso terapêutico , Imunofluorescência , Células HeLa , História do Século XIX , Humanos , Técnicas In Vitro , Organofosfonatos/uso terapêutico , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Varíola/história , Estados Unidos
8.
Biotechniques ; 50(5): 303-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21548892

RESUMO

Vaccinia virus has been a powerful tool in molecular biology and vaccine development. The relative ease of inserting and expressing foreign genes combined with its broad host range has made it an attractive antigen delivery system against many heterologous diseases. Many different approaches have been developed to isolate recombinant vaccinia virus generated from homologous recombination; however, most are time-consuming, often requiring a series of passages or specific cell lines. Herein we introduce a rapid method for isolating recombinants using the antibiotic coumermycin and the interferon-associated PKR pathway to select for vaccinia virus recombinants. This method uses a negative selection marker in the form of a fusion protein, GyrB-PKR, consisting of the coumermycin dimerization domain of Escherichia coli gyrase subunit B fused to the catalytic domain of human PKR. Coumermycin-dependent dimerization of this protein results in activation of PKR and the phosphorylation of translation initiation factor, eIF2α. Phosphorylation of this factor leads to an inhibition of protein synthesis, and an inhibition of virus replication. In the presence of coumermycin, recombinants are isolated due to the loss of this coumermycin-sensitive gene by homologous recombination. We demonstrate that this method of selection is highly efficient and requires limited rounds of enrichment to isolate recombinant virus.


Assuntos
Fator de Iniciação 2 em Eucariotos/química , Vaccinia virus/isolamento & purificação , Aminocumarinas/química , Aminocumarinas/farmacologia , Animais , Linhagem Celular , Cricetinae , Dimerização , Escherichia coli/genética , Escherichia coli/metabolismo , Vetores Genéticos , Especificidade de Hospedeiro/efeitos dos fármacos , Inibidores da Síntese de Proteínas/química , Inibidores da Síntese de Proteínas/farmacologia , Coelhos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/efeitos dos fármacos , Proteínas Recombinantes/isolamento & purificação , Recombinação Genética/efeitos dos fármacos , Vaccinia virus/efeitos dos fármacos , Vaccinia virus/crescimento & desenvolvimento , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
9.
J Biol Chem ; 286(10): 7765-7778, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21183678

RESUMO

PKR is a potent antiviral molecule that can terminate infection by inhibiting protein synthesis and stimulating NF-κB activation and apoptosis. Originally, it was thought that only intermediate and late gene transcription produced double-stranded (ds) RNA to activate PKR during vaccinia virus (VACV) infection. The VACV E3 or K3 proteins squelch this effect by binding to either dsRNA or PKR. However, in the absence of the K1 protein, VACV infection activates PKR at very early times post-infection and despite the presence of E3 and K3. These data suggest that VACV infection induces PKR activation by a currently unknown mechanism. To determine this mechanism, cells were infected with K1L-containing or -deficient VACVs. By using conditions that limited the progression of the poxvirus replication cycle, we observed that early gene transcripts activated PKR in RK13 cells, identifying a new PKR-activating mechanism of poxvirus infection. Using a similar approach for HeLa cells, intermediate gene transcription was sufficient to activate PKR. RNA isolated from infected RK13 or HeLa cells maintained PKR-activating properties only when dsRNA was present. Moreover, viral dsRNA was directly detected in infected cells either by RT-PCR or immunofluorescent microscopy. Interestingly, dsRNA levels were higher in infected cells in which the K1 protein was nonfunctional. Only K1 proteins with PKR inhibitory function prevented downstream NF-κB activation. These results reveal a new PKR activation pathway during VACV infection, in which the K1 protein reduces dsRNA levels early in VACV infection to directly inhibit PKR and several of its downstream antiviral effects, thereby enhancing virus survival.


Assuntos
Mutação , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA de Cadeia Dupla/metabolismo , RNA Viral/metabolismo , Vaccinia virus/metabolismo , Vacínia/metabolismo , Proteínas Virais/metabolismo , Animais , Ativação Enzimática , Células HeLa , Humanos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA de Cadeia Dupla/genética , RNA Viral/genética , Coelhos , Transcrição Gênica/genética , Vacínia/genética , Vaccinia virus/genética , Proteínas Virais/genética
10.
PLoS One ; 5(9): e12561, 2010 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-20838436

RESUMO

Many hundreds of botanicals are used in complementary and alternative medicine for therapeutic use as antimicrobials and immune stimulators. While there exists many centuries of anecdotal evidence and few clinical studies on the activity and efficacy of these botanicals, limited scientific evidence exists on the ability of these botanicals to modulate the immune and inflammatory responses. Using botanogenomics (or herbogenomics), this study provides novel insight into inflammatory genes which are induced in peripheral blood mononuclear cells following treatment with immunomodulatory botanical extracts. These results may suggest putative genes involved in the physiological responses thought to occur following administration of these botanical extracts. Using extracts from immunostimulatory herbs (Astragalus membranaceus, Sambucus cerulea, Andrographis paniculata) and an immunosuppressive herb (Urtica dioica), the data presented supports previous cytokine studies on these herbs as well as identifying additional genes which may be involved in immune cell activation and migration and various inflammatory responses, including wound healing, angiogenesis, and blood pressure modulation. Additionally, we report the presence of lipopolysaccharide in medicinally prepared extracts of these herbs which is theorized to be a natural and active component of the immunostimulatory herbal extracts. The data presented provides a more extensive picture on how these herbs may be mediating their biological effects on the immune and inflammatory responses.


Assuntos
Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Inflamação/genética , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Extratos Vegetais/farmacologia , Andrographis/química , Astragalus propinquus/química , Células Cultivadas , Humanos , Fatores Imunológicos/imunologia , Inflamação/imunologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Extratos Vegetais/imunologia , Sambucus/química , Urtica dioica/química
11.
Antiviral Res ; 84(1): 1-13, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19563829

RESUMO

Vaccinia virus (VACV) has been used more extensively for human immunization than any other vaccine. For almost two centuries, VACV was employed to provide cross-protection against variola virus, the causative agent of smallpox, until the disease was eradicated in the late 1970s. Since that time, continued research on VACV has produced a number of modified vaccines with improved safety profiles. Attenuation has been achieved through several strategies, including sequential passage in an alternative host, deletion of specific genes or genetic engineering of viral genes encoding immunomodulatory proteins. Some highly attenuated third- and fourth-generation VACV vaccines are now being considered for stockpiling against a possible re-introduction of smallpox through bioterrorism. Researchers have also taken advantage of the ability of the VACV genome to accommodate additional genetic material to produce novel vaccines against a wide variety of infectious agents, including a recombinant VACV encoding the rabies virus glycoprotein that is administered orally to wild animals. This review provides an in-depth examination of these successive generations of VACV vaccines, focusing on how the understanding of poxviral replication and viral gene function permits the deliberate modification of VACV immunogenicity and virulence.


Assuntos
Vacina Antivariólica/história , Vaccinia virus/genética , Vaccinia virus/imunologia , Vacínia/prevenção & controle , Animais , Engenharia Genética , História do Século XX , História do Século XXI , Humanos , Vacina Antivariólica/genética , Vacina Antivariólica/imunologia , Vacínia/imunologia , Vacínia/virologia , Vaccinia virus/patogenicidade , Vaccinia virus/fisiologia , Virulência
12.
J Virol ; 83(11): 5718-25, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19321614

RESUMO

The p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs) play important roles in the host innate immune response. The protein kinase regulated by RNA (PKR) is implicated in p38 MAPK activation in response to proinflammatory signals in mouse embryonic fibroblasts. To test the role of PKR in the activation of p38 and JNK MAPKs in human cells following viral infection, HeLa cells made stably deficient in PKR by using an RNA interference strategy were compared to cells with sufficient PKR. The phosphorylation of both p38 and JNK in cells with sufficient PKR was activated following either infection with an E3L deletion (DeltaE3L) mutant of vaccinia virus or transfection with double-stranded RNA (dsRNA) in the absence of infection with wild-type vaccinia virus. The depletion of PKR by stable knockdown impaired the phosphorylation of both p38 and JNK induced by either the DeltaE3L mutant virus or dsRNA but not that induced by tumor necrosis factor alpha. The PKR-dependent activation of MAPKs in DeltaE3L mutant-infected cells was abolished by treatment with cytosine beta-d-arabinoside. The complementation of PKR-deficient cells with the human PKR wild-type protein, but not with the PKR catalytic mutant (K296R) protein, restored p38 and JNK phosphorylation following DeltaE3L mutant virus infection. Transient small interfering RNA knockdown established that the p38 and JNK kinase activation following DeltaE3L infection was dependent upon RIG-I-like receptor signal transduction pathway components, including the mitochondrial adapter IPS-1 protein.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas de Ligação a RNA/metabolismo , Vaccinia virus/metabolismo , Proteínas Virais/metabolismo , eIF-2 Quinase/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Âmnio/enzimologia , Linhagem Celular , Ativação Enzimática , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Fosforilação , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Vaccinia virus/genética , Proteínas Virais/genética , eIF-2 Quinase/genética
13.
Vaccine ; 26(23): 2860-72, 2008 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-18455281

RESUMO

In this study, we evaluated the efficacy of vaccinia virus (VACV) containing mutations in the E3L virulence gene to protect mice against a lethal poxvirus challenge after vaccination by scarification. VACV strains with mutations in the E3L gene had significantly decreased pathogenicity, even in immune deficient mice, yet retained the ability to produce a potent Th1-dominated immune response in mice after vaccination by scarification, while protecting against challenge with wild type, pathogenic VACV. Initial experiments were done using the mouse-adapted, neurovirulent Western Reserve (WR) strain of vaccinia virus. Testing of the full E3L deletion mutation in the Copenhagen and NYCBH strains of VACV, which are more appropriate for use in humans, produced similar results. These results suggest that highly attenuated strains of VACV containing mutations in E3L have the potential for use as scarification administered vaccines.


Assuntos
Vaccinia virus/genética , Vacínia/imunologia , Vacínia/prevenção & controle , Vacinas Virais/genética , Administração Intranasal , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/biossíntese , Antivirais/farmacologia , Células Cultivadas , Ensaio Cometa , Cricetinae , Citocinas/biossíntese , Farmacorresistência Viral/genética , Feminino , Genes Virais/genética , Genes Virais/imunologia , Imunidade Celular/imunologia , Interferons/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Mutação/genética , Mutação/imunologia , Testes de Neutralização , Coelhos , Baço/citologia , Baço/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Replicação Viral
14.
J Virol ; 81(6): 2554-63, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17182678

RESUMO

The recent emergence of several new coronaviruses, including the etiological cause of severe acute respiratory syndrome, has significantly increased the importance of understanding virus-host cell interactions of this virus family. We used mouse hepatitis virus (MHV) A59 as a model to gain insight into how coronaviruses affect the type I alpha/beta interferon (IFN) system. We demonstrate that MHV is resistant to type I IFN. Protein kinase R (PKR) and the alpha subunit of eukaryotic translation initiation factor are not phosphorylated in infected cells. The RNase L activity associated with 2',5'-oligoadenylate synthetase is not activated or is blocked, since cellular RNA is not degraded. These results are consistent with lack of protein translation shutoff early following infection. We used a well-established recombinant vaccinia virus (VV)-based expression system that lacks the viral IFN antagonist E3L to screen viral genes for their ability to rescue the IFN sensitivity of the mutant. The nucleocapsid (N) gene rescued VVDeltaE3L from IFN sensitivity. N gene expression prevents cellular RNA degradation and partially rescues the dramatic translation shutoff characteristic of the VVDeltaE3L virus. However, it does not prevent PKR phosphorylation. The results indicate that the MHV N protein is a type I IFN antagonist that likely plays a role in circumventing the innate immune response.


Assuntos
Interferon Tipo I/farmacologia , Vírus da Hepatite Murina/metabolismo , Proteínas do Nucleocapsídeo/antagonistas & inibidores , Animais , Linhagem Celular , Proteínas do Nucleocapsídeo de Coronavírus , Relação Dose-Resposta a Droga , Endorribonucleases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Genes Virais , Células HeLa , Humanos , Camundongos , Modelos Biológicos , Vírus da Hepatite Murina/genética , Proteínas do Nucleocapsídeo/genética , Fosforilação/efeitos dos fármacos , Recombinação Genética , Vaccinia virus/genética , eIF-2 Quinase/metabolismo
15.
J Virol ; 80(20): 10083-95, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17005686

RESUMO

Cells have evolved elaborate mechanisms to counteract the onslaught of viral infections. To activate these defenses, the viral threat must be recognized. Danger signals, or pathogen-associated molecular patterns, that are induced by pathogens include double-stranded RNA (dsRNA), viral single-stranded RNA, glycolipids, and CpG DNA. Understanding the signal transduction pathways activated and host gene expression induced by these danger signals is vital to understanding virus-host interactions. The vaccinia virus E3L protein is involved in blocking the host antiviral response and increasing pathogenesis, functions that map to separate C-terminal dsRNA- and N-terminal Z-DNA-binding domains. Viruses containing mutations in these domains allow modeling of the role of dsRNA and Z-form nucleic acid in the host response to virus infection. Deletions in the Z-DNA- or dsRNA-binding domains led to activation of signal transduction cascades and up-regulation of host gene expression, with many genes involved in the inflammatory response. These data suggest that poxviruses actively inhibit cellular recognition of viral danger signals and the subsequent cellular response to the viral threat.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Ligação a RNA/fisiologia , Transdução de Sinais , Vaccinia virus/imunologia , Proteínas Virais/fisiologia , Proteínas de Ligação a DNA/genética , Células HeLa , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Estrutura Terciária de Proteína , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Deleção de Sequência , Vaccinia virus/fisiologia , Proteínas Virais/química , Proteínas Virais/genética
16.
Virus Res ; 119(1): 100-10, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16704884

RESUMO

Interferons were the first of the anti-viral innate immune modulators to be characterized, initially characterized solely as anti-viral proteins [reviewed in Le Page, C., Genin, P., Baines, M.G., Hiscott, J., 2000. Inteferon activation and innate immunity. Rev. Immunogenet. 2, 374-386]. As we have progressed in our understanding of the interferons they have taken a more central role in our understanding of innate immunity and its interplay with the adaptive immune response. One of the key players in function of interferon is the interferon-inducible enzyme, protein kinase (PKR, activatable by RNA). The key role played by PKR in the innate response to virus infection is emphasized by the large number of viruses, DNA viruses as well as RNA viruses, whose hosts range from insects to humans, that code for PKR inhibitors. In this review we will first describe activation of PKR and then describe the myriad of ways that viruses inhibit function of PKR.


Assuntos
Vírus de DNA/patogenicidade , Vírus de RNA/patogenicidade , eIF-2 Quinase/antagonistas & inibidores , Animais , Vírus de DNA/metabolismo , Humanos , Imunidade Inata , Interferons/metabolismo , Vírus de RNA/metabolismo , eIF-2 Quinase/metabolismo
17.
Virology ; 324(2): 419-29, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15207627

RESUMO

The process of eukaryotic translation initiation can be regulated by a highly conserved mechanism involving the phosphorylation of the translation initiation factor eIF2 on the alpha subunit. This mechanism is recognized as an efficient step in the host antiviral response. Vaccinia virus (VV), like many other viruses, encodes proteins to overcome this inhibitory process. The C-terminus of the vaccinia virus E3L is known to bind to double-stranded RNA (dsRNA) thereby sequestering the activator of this antiviral response. In this report, the N-terminus of E3L was found to be required for the additional regulation of eIF2alpha phosphorylation. This phosphorylation event did not lead to a global shutdown in protein synthesis. Because the N-terminus of E3L is required for full viral pathogenesis in mice, these results suggest an alternative role of eIF2alpha phosphorylation in regulating viral replication.


Assuntos
Proteínas de Ligação a RNA/metabolismo , Vaccinia virus/patogenicidade , Vacínia/virologia , Proteínas Virais/metabolismo , eIF-2 Quinase/metabolismo , Animais , Deleção de Genes , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteínas de Ligação a RNA/genética , Sequências Repetidas Terminais , Fatores de Tempo , Vacínia/metabolismo , Vaccinia virus/crescimento & desenvolvimento , Proteínas Virais/genética , eIF-2 Quinase/antagonistas & inibidores
18.
J Interferon Cytokine Res ; 23(9): 489-500, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14565858

RESUMO

Nuclear factor-90 (NF-90) has been described as a regulatory subunit of a complex containing DNA-dependent protein kinase (DNA-PK), Ku, and NF-45, which are capable of binding the interleukin-2 (IL-2) enhancer region and stimulating IL-2 gene expression. Vaccinia virus (VV) infection of Jurkat cells induced a nuclear factor that bound specifically to the IL-2 promoter sequence and led to the expression of the IL-2 transcript. Induction of this IL-2 promoter binding factor occurred concomitantly with the induction of NF-90 and translocation of NF-90 to the nucleus. Electrophoretic mobility supershift analysis using specific anti-NF-90 serum suggested the presence of NF-90 in the IL-2 promoter binding complex. As NF-90 can bind to double-stranded RNA (dsRNA) and be phosphorylated by the dsRNA-dependent protein kinase, PKR, we investigated whether accumulation of dsRNA in VV-infected cells could regulate IL-2 gene expression. Infection of Jurkat cells with a VV mutant that produces free dsRNA led to similar levels of induced NF-90 within the cell, but the protein remained localized within the cytosol. This mutant did not lead to the accumulation of an IL-2 promoter binding complex or to the synthesis of IL-2 mRNA. Other VV mutants that produced excess dsRNA also inhibited protein binding to the IL-2 enhancer, suggesting that the presence of viral dsRNA has a role in retaining NF-90 in the cytosol and regulating IL-2 gene expression.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Interleucina-2/genética , Proteínas Nucleares , Infecções por Poxviridae/metabolismo , RNA de Cadeia Dupla/metabolismo , Fatores de Transcrição/metabolismo , Vaccinia virus/metabolismo , Humanos , Interleucina-2/biossíntese , Células Jurkat , Fatores de Transcrição NFATC , Proteína do Fator Nuclear 45 , Proteínas do Fator Nuclear 90 , Infecções por Poxviridae/genética , Transporte Proteico , Vaccinia virus/genética
19.
Virology ; 314(1): 305-14, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-14517083

RESUMO

Orf virus (OV), the prototypic parapoxvirus, is resistant to the effects of interferon (IFN) and this function of OV has been mapped to the OV20.0L gene. The protein product of this gene shares 31% amino acid identity to the E3L-encoded protein of vaccinia virus (VV) that is required for the broad host range and IFN-resistant phenotype of VV in cells in culture and for virulence of the virus in vivo. In this study we investigated whether the distantly related OV E3L homologue could complement the deletion of E3L in VV. The recombinant VV (VV/ORF-E3L) expressing the OV E3L homologue in place of VV E3L was indistinguishable from wt VV in its cell-culture phenotype. But VV/ORF-E3L was over a 1000-fold less pathogenic than wt VV (LD(50) > 5 x 10(6) PFU, compared to LD(50) of wtVV = 4 x 10(3) PFU) following intranasal infection of mice. While wt VV spread to the lungs and brain and replicated to high titers in the brain of infected mice, VV/ORF-E3L could not be detected in the lungs or brain following intranasal infection. VV/ORF-E3L was at least 100,000-fold less pathogenic than wt VV on intracranial injection. Domain swap experiments demonstrate that the difference in pathogenesis maps to the C-terminal domain of these proteins. This domain has been shown to be required for the dsRNA binding function of the VV E3L.


Assuntos
Deleção de Genes , Teste de Complementação Genética , Vírus do Orf/patogenicidade , Proteínas de Ligação a RNA/genética , Homologia de Sequência de Aminoácidos , Vaccinia virus/patogenicidade , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Humanos , Interferon beta/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Vírus do Orf/genética , Proteínas de Ligação a RNA/metabolismo , Recombinação Genética , Alinhamento de Sequência , Vacínia/fisiopatologia , Vacínia/virologia , Vaccinia virus/genética , Ensaio de Placa Viral , Proteínas Virais/metabolismo , Virulência
20.
Virology ; 299(1): 133-41, 2002 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-12167348

RESUMO

Vaccinia virus encodes two regulators of the cellular antiviral response. The E3L gene is thought to act primarily by sequestering double-stranded RNA, whereas the K3L gene is thought to act as a competitive inhibitor of the double-stranded RNA-dependent protein kinase, PKR. The broad host range associated with vaccinia virus replication appears to be related to the presence of these genes. The E3L gene is required for replication in HeLa cells, but is not required for replication in BHK cells. On the contrary, the K3L gene is required for replication in BHK cells, but is dispensable for replication in HeLa cells. Our results suggest that these cell lines varied in the expression of endogenous activatable PKR and that replication of vaccinia virus in different cell lines led to altered levels of double-stranded RNA synthesis from the virus. Vaccinia virus was able to overcome these cellular variations by regulating PKR activity through the synthesis of either E3L or K3L. The results suggest that vaccinia virus has evolved a broad host range by maintaining both the E3L and the K3L genes.


Assuntos
Proteínas de Ligação a RNA/fisiologia , Vaccinia virus/fisiologia , Proteínas Virais/fisiologia , eIF-2 Quinase/antagonistas & inibidores , Animais , Linhagem Celular , Cricetinae , Células HeLa , Humanos , RNA de Cadeia Dupla/biossíntese , Proteínas de Ligação a RNA/genética , Vaccinia virus/genética , Proteínas Virais/genética , Replicação Viral , eIF-2 Quinase/metabolismo
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