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1.
J Dermatol ; 50(9): 1140-1144, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37334747

RESUMO

Immunity is known to persist after vaccination for varicella zoster virus, but the duration of immunity in patients who develop herpes zoster (HZ) remains unknown. To investigate the association between a past history of HZ and its occurrence in the general population. The Shozu HZ (SHEZ) cohort study included data for 12 299 individuals aged ≥50 years with information on their HZ history. Cross-sectional and 3-year follow-up studies were carried out to analyze the associations between a history of HZ (yes <10 years, yes ≥10 years, no) and the proportion of positive varicella zoster virus skin test results (erythema diameter ≥5 mm) and the risk of HZ after adjusting for potential confounding factors including age, sex, body mass index, smoking status, sleep duration, and mental stress. The incidences of positive skin test results were 87.7% (470/536) for individuals with a history of HZ <10 years ago, 82.2% (396/482) for those with a history of HZ ≥10 years, and 80.2% (3614/4509) for those with no history of HZ. The multivariable odds ratios (95% confidence intervals) of erythema diameter ≥5 mm were 2.07 (1.57-2.73) and 1. 39 (1.08-1.80) for individuals with a history <10 years and ≥10 years ago, respectively, compared with no history. The corresponding multivariable hazard ratios of HZ were 0.54 (0.34-0.85) and 1.16 (0.83-1.61), respectively. A past history of HZ <10 years ago may reduce the occurrence of HZ.


Assuntos
Herpes Zoster , Herpesvirus Humano 3 , Humanos , Estudos de Coortes , Estudos Transversais , População do Leste Asiático , Herpes Zoster/epidemiologia , Herpes Zoster/imunologia , Incidência , Reinfecção/epidemiologia , Reinfecção/imunologia , Japão/epidemiologia
2.
J Dermatol ; 50(8): 1020-1033, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37208823

RESUMO

The authors aimed to identify determinants of the clinical course of herpes zoster and immunological responses, focusing on pain trajectories. This prospective community-based cohort study involved the analysis of responses to a valid pain survey provided by 375 patients diagnosed with herpes zoster based on clinical symptoms and virus identification by polymerase chain reaction. The authors analyzed most patients for humoral/cell-mediated immune response against varicella-zoster virus at the onset and 3 months post-onset. Six months post-initial visit, patients self-reported pain on a scale of 0 (no pain) to 5 (extremely strong pain) at up to 18 time points. Moreover, the pain trajectories were traced using group-based trajectory modeling. Subsequently, the authors used analysis of covariance to explore predictors and the humoral/cell-mediated immune response according to the pain trajectories. In addition, humoral/cell-mediated immune responses were assessed among each trajectory using paired t tests. Amon the five identified trajectories, two were isolated that particularly developed postherpetic neuralgia, with or without severe acute pain. Cancer therapy and corticosteroid use before herpes zoster onset specifically predicted postherpetic neuralgia without severe acute pain. In contrast, prescription of nonsteroidal anti-inflammatory drugs was uniquely associated with postherpetic neuralgia accompanied by severe acute pain. The aforementioned trajectories with postherpetic neuralgia showed increased antibodies and decreased cell-mediated immunity compared with those without postherpetic neuralgia. The authors could successfully distinguish between postherpetic neuralgia trajectories with and without severe acute pain. The identified key predictors and immunological responses against varicella-herpes zoster contribute further evidence to our understanding of the clinical features of herpes zoster and postherpetic neuralgia.


Assuntos
Dor Aguda , Herpes Zoster , Neuralgia Pós-Herpética , Humanos , Herpesvirus Humano 3 , Estudos Prospectivos , Dor Aguda/complicações , Estudos de Coortes , Herpes Zoster/tratamento farmacológico , Imunidade
3.
J Sci Food Agric ; 98(5): 1899-1905, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28902408

RESUMO

BACKGROUND: The present study was conducted aiming to examine the antiviral activity of adlay tea and its components against influenza viruses. We further aimed to clarify the mechanism by which these components regulate virus replication. RESULTS: Adlay tea at a concentration suitable for drinking inhibited the multiplication of influenza viruses. Moreover, our results suggest that individual components of the tea had antiviral activities against the influenza A/PR/8/34 virus. Adlay tea inhibited multiplication of the H1N1, H3N2 and B types of influenza virus, including oseltamivir-resistant viruses. In addition, adlay tea inhibited influenza infection during the periods of virus adsorption to the cell and virus replication. Adlay tea did not suppress hemagglutination inhibition or cell fusion, although it slightly inhibited virus binding to Malin Darby canine kidney cells. Furthermore, our findings suggest that the antiviral compounds included in adlay tea were ingredients other than polyphenols and that there were several types of effective compounds in adlay tea inhibiting several steps of viral replication. CONCLUSION: The results of the present study demonstrate that adlay tea had antiviral effects against influenza viruses. Our findings with respect to adlay tea suggest that the polyphenols might have a small influence on its antiviral activity and that other ingredients might have more influence. © 2017 Society of Chemical Industry.


Assuntos
Antivirais/farmacologia , Coix/química , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Influenza Humana/virologia , Preparações de Plantas/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Cães , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/fisiologia , Vírus da Influenza B/genética , Vírus da Influenza B/fisiologia , Células Madin Darby de Rim Canino
4.
Arch Virol ; 163(2): 419-425, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29101537

RESUMO

We analyzed two virus variants (S1 and L1) from Seoul orthohantavirus strain B1. Strain B1 produces large opaque plaques when plated on Vero E6 cell monolayers. However, although the L1 variant produced the large opaque plaques common to the strain, the variant S1 produced small clear ones on Vero E6 cells. Five days after Vero E6 cells were infected with the S1 variant, polykaryons formed spontaneously. However, the cells infected with the L1 variant did not show the formation of syncytia. An analysis of the pH dependency of the cell fusion demonstrated that the L1 variant could induce cell fusion, but only at a pH that was 0.2 units lower than the pH at which the S1 variant induced it. Sequencing of the M genome segment of the two virus variants revealed amino acid substitutions at 4 positions in the Gn and Gc gene products of the S1 variant. Two of these substitutions occurred in the extracellular domain of Gn and changed the charge of the protein. Our findings suggest that these amino acid substitutions caused the S1 variant Gn protein to induce fusion at an elevated pH.


Assuntos
Infecções por Vírus de RNA/virologia , Vírus de RNA/fisiologia , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus , Animais , Fusão Celular , Chlorocebus aethiops , Células Gigantes/virologia , Infecções por Vírus de RNA/fisiopatologia , Vírus de RNA/genética , Células Vero , Proteínas do Envelope Viral/genética
5.
Am J Epidemiol ; 187(2): 251-259, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036443

RESUMO

In the present population-based prospective study, we examined the associations of psychosocial factors with the incidence of herpes zoster (HZ) and postherpetic neuralgia (PHN). Data were collected from 12,359 participants (≥50 years of age) who answered a self-completed health questionnaire in the Shozu County of Kagawa Prefecture in Japan. During a 3-year follow-up between December 2008 and November 2012, HZ and PHN were diagnosed in 400 and 79 subjects, respectively. We used Cox regression analysis to estimate hazard ratios of incident HZ and PHN according to psychosocial factors, adjusting for age, sex, histories of HZ, cancer, and diabetes, smoking and drinking habits, and time from disease onset to treatment. Men with high levels of mental stress were twice as likely to be at risk for incident HZ. The risk of incident HZ was approximately 60% lower among men and women who reported a high sense of purpose in life. Women who experienced negative life events-particularly changes in their work, living environment, and relationships-had a 2- to 3-fold higher risk of incident PHN. Psychosocial factors such as perceived mental stress, sense of purpose in life, and negative life events may contribute to the development of HZ and PHN in the general population.


Assuntos
Herpes Zoster/epidemiologia , Acontecimentos que Mudam a Vida , Neuralgia Pós-Herpética/epidemiologia , Autoimagem , Estresse Psicológico/virologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Herpes Zoster/psicologia , Herpesvirus Humano 3 , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Neuralgia Pós-Herpética/psicologia , Percepção , Modelos de Riscos Proporcionais , Análise de Regressão , Fatores de Risco
6.
BMC Cancer ; 17(1): 89, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28143428

RESUMO

BACKGROUND: BK-UM (CRM197) is a mutant form of diphtheria toxin and a specific inhibitor of heparin-binding epidermal growth factor-like growth factor (HB-EGF). We assessed the safety, pharmacokinetics, recommended dose, and efficacy of BK-UM in patients with recurrent ovarian cancer (OC) or peritoneal cancer (PC), and measured HB-EGF levels in serum and abdominal fluid after BK-UM administration. METHODS: Eleven patients with advanced or recurrent OC or PC were enrolled and treated with BK-UM via the intraperitoneal route. The dose was escalated (1.0, 2.0, 3.3, and 5.0 mg/m2) using a 3 + 3 design. RESULTS: Eight of 11 patients completed treatment. No dose-limiting toxicity (DLT) was experienced at dose levels 1 (1.0 mg/m2) and 2 (2.0 mg/m2). Grade 3 transient hypotension as an adverse event (defined as a DLT in the present study) was observed in two of four patients at dose level 3 (3.3 mg/m2). Treatment with BK-UM was associated with decreases in HB-EGF levels in serum and abdominal fluid in seven of 11 patients and five of eight patients, respectively. Clinical outcomes included a partial response in one patient, stable disease in five patients, and progressive disease in five patients. CONCLUSIONS: BK-UM was well tolerated at doses of 1.0 and 2.0 mg/m2, with evidence for clinical efficacy in patients with recurrent OC or PC. A dose of 2.0 mg/m2 BK-UM is recommended for subsequent clinical trials. TRIAL REGISTRATION: This trial was prospectively performed as an investigator-initiated clinical trial. The trial numbers are UMIN000001002 and UMIN000001001, with registration dates of 1/30/2008 and 2/4/2008, respectively. UMIN000001001 was registered as a trial for the continuous administration of BK-UM after UMIN000001002 .


Assuntos
Proteínas de Bactérias/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Idoso , Proteínas de Bactérias/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/metabolismo , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Peritoneais/metabolismo
7.
J Am Acad Dermatol ; 75(5): 950-956.e1, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27473453

RESUMO

BACKGROUND: Recurrent herpes zoster (HZ) is thought to be rare, but there have been few large-scale studies of recurrent HZ. OBJECTIVE: We conducted a large-scale prospective cohort study to characterize recurrent HZ. METHODS: We examined 12,522 participants aged 50 years or older in Shozu County and followed them up for 3 years. We compared the incidence of HZ and postherpetic neuralgia, severity of skin lesions and acute pain, cell-mediated immunity, and varicella-zoster virus-specific antibody titer between primary and recurrent HZ. RESULTS: A total of 401 participants developed HZ: 341 with primary HZ and 60 with recurrent HZ. Skin lesions and acute pain were significantly milder and the incidence of postherpetic neuralgia was lower in patients aged 50 to 79 years with recurrent HZ than in those with primary HZ. Varicella-zoster virus skin test induced a stronger reaction in patients aged 50 to 79 years with recurrent HZ than in those with primary HZ. LIMITATIONS: Information on previous HZ episodes was self-reported by participants, so it could not be confirmed that they actually had a history of HZ. CONCLUSION: Recurrent HZ was associated with milder clinical symptoms than primary HZ, probably because of stronger varicella-zoster virus-specific cell-mediated immunity in the patients with recurrence.


Assuntos
Herpes Zoster , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Comorbidade , Feminino , Herpes Zoster/epidemiologia , Herpes Zoster/imunologia , Herpes Zoster/patologia , Herpes Zoster/virologia , Herpesvirus Humano 3/imunologia , Humanos , Imunidade Celular , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Incidência , Testes Intradérmicos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neuralgia Pós-Herpética/epidemiologia , Medição da Dor , Estudos Prospectivos , Recidiva
8.
mBio ; 6(2)2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25852160

RESUMO

UNLABELLED: A change in viral hemagglutinin (HA) receptor binding specificity from α2,3- to α2,6-linked sialic acid is necessary for highly pathogenic avian influenza (AI) virus subtype H5N1 to become pandemic. However, details of the human-adaptive change in the H5N1 virus remain unknown. Our database search of H5N1 clade 2.2.1 viruses circulating in Egypt identified multiple HA mutations that had been selected in infected patients. Using reverse genetics, we found that increases in both human receptor specificity and the HA pH threshold for membrane fusion were necessary to facilitate replication of the virus variants in human airway epithelia. Furthermore, variants with enhanced replication in human cells had decreased HA stability, apparently to compensate for the changes in viral receptor specificity and membrane fusion activity. Our findings showed that H5N1 viruses could rapidly adapt to growth in the human airway microenvironment by altering their HA properties in infected patients and provided new insights into the human-adaptive mechanisms of AI viruses. IMPORTANCE: Circulation between bird and human hosts may allow H5N1 viruses to acquire amino acid changes that increase fitness for human infections. However, human-adaptive changes in H5N1 viruses have not been adequately investigated. In this study, we found that multiple HA mutations were actually selected in H5N1-infected patients and that H5N1 variants with some of these HA mutations had increased human-type receptor specificity and increased HA membrane fusion activity, both of which are advantageous for viral replication in human airway epithelia. Furthermore, HA mutants selected during viral replication in patients were likely to have less HA stability, apparently as a compensatory mechanism. These results begin to clarify the picture of the H5N1 human-adaptive mechanism.


Assuntos
Variação Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Humana/virologia , Mutação de Sentido Incorreto , Adaptação Biológica , Animais , Células Cultivadas , Modelos Animais de Doenças , Células Epiteliais/virologia , Humanos , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/virologia , Análise de Sobrevida
9.
J Gen Virol ; 95(Pt 11): 2365-2371, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25053564

RESUMO

Whole-virus (WV) vaccines from influenza A/duck/Hokkaido/77 (H3N2), and its reassortant strains H3N4, H3N5 and H3N7, which have the same haemagglutinin (HA) gene but different neuraminidase (NA) genes, were prepared from our influenza virus library. Mice were intranasally immunized with equivalent doses of each vaccine (1-0.01 µg per mouse). All of the mice that received the highest dose of each vaccine (1 µg per mouse) showed equivalent high HA-inhibiting (HI) antibody titres and survived the H3N2 challenge viruses. However, mice that received lower doses of vaccine (0.1 or 0.01 µg per mouse) containing a heterologous NA had lower survival rates than those given the H3N2-based vaccine. The lungs of mice challenged with H3N2 virus showed a significantly higher virus clearance rate when the vaccine contained the homologous NA (N2) versus a heterologous NA, suggesting that NA contributed to the protection, especially when the HI antibody level was low. These results suggested that, even if vaccines prepared for a possible upcoming pandemic do not induce sufficient HI antibodies, WV vaccines can still be effective through other matched proteins such as NA.


Assuntos
Genes Virais , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Neuraminidase/genética , Neuraminidase/imunologia , Animais , Anticorpos Antivirais/sangue , Feminino , Biblioteca Gênica , Vírus da Influenza A Subtipo H3N2/enzimologia , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Vírus Reordenados/enzimologia , Vírus Reordenados/genética , Vírus Reordenados/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia
10.
Antiviral Res ; 98(3): 423-31, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23545366

RESUMO

Public health concern about dengue diseases, caused by mosquito-borne infections with four serotypes of dengue virus (DENV-1-DENV-4), is escalating in tropical and subtropical countries. Most of the severe dengue cases occur in patients experiencing a secondary infection with a serotype that is different from the first infection. This is believed to be due to antibody-dependent enhancement (ADE), by which one DENV serotype uses pre-existing anti-DENV antibodies elicited in the primary infection to facilitate entry of a different DENV serotype into the Fc receptor-positive macrophages. Recently, we prepared a number of hybridomas producing human monoclonal antibodies (HuMAbs) by using peripheral blood lymphocytes from Thai patients at acute phase of secondary infection with DENV-2. Here, we characterized 17 HuMAbs prepared from two patients with dengue fever (DF) and one patient with dengue hemorrhagic fever (DHF) that were selected as antibodies recognizing viral envelope protein and showing higher neutralization activity to all serotypes. In vivo evaluation using suckling mice revealed near perfect activity to prevent mouse lethality following intracerebral DENV-2 inoculation. In a THP-1 cell assay, these HuMAbs showed ADE activities against DENV-2 at similar levels between HuMAbs derived from DF and DHF patients. However, the F(ab')2 fragment of the HuMAb showed a similar virus neutralization activity as original, with no ADE activity. Thus, these HuMAbs could be one of the therapeutic candidates against DENV infection.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores , Vírus da Dengue/imunologia , Dengue/terapia , Adulto , Animais , Anticorpos Monoclonais/uso terapêutico , Antivirais/imunologia , Antivirais/uso terapêutico , Coinfecção/imunologia , Coinfecção/virologia , Dengue/imunologia , Vírus da Dengue/patogenicidade , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Hibridomas/imunologia , Hibridomas/virologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Índice de Gravidade de Doença , Proteínas do Envelope Viral/imunologia , Internalização do Vírus , Adulto Jovem
11.
Anticancer Res ; 31(7): 2553-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21873174

RESUMO

BACKGROUND: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a rational target for ovarian cancer therapy. The aim of this study was to examine HB-EGF levels in the peritoneal fluid and serum of ovarian cancer (OVCA) patients. PATIENTS AND METHODS: Samples were collected from six healthy women, 21 OVCA patients, and 21 ovarian cyst patients. HB-EGF levels were measured using a sandwich ELISA kit and calculated using a parallel line assay. RESULTS: No significant difference between the slopes of the standard and sample curves was observed at an anti-HB-EGF antibody concentration of 1.6 µg/ml. HB-EGF levels in the peritoneal fluid and serum of OVCA patients were significantly higher than those in patients with ovarian cysts or controls. Serum HB-EGF levels were also significantly correlated with levels in peritoneal fluid in OVCA patients. CONCLUSION: We developed an assay for the exact measurement of HB-EGF levels in peritoneal fluid and serum.


Assuntos
Líquido Ascítico/química , Ensaio de Imunoadsorção Enzimática , Peptídeos e Proteínas de Sinalização Intercelular/análise , Proteínas de Neoplasias/análise , Neoplasias Ovarianas/metabolismo , Adulto , Idoso , Anticorpos/imunologia , Afinidade de Anticorpos , Especificidade de Anticorpos , Artefatos , Ligação Competitiva , Biomarcadores Tumorais , Feminino , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Pessoa de Meia-Idade , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/imunologia , Cistos Ovarianos/sangue , Cistos Ovarianos/metabolismo , Neoplasias Ovarianas/sangue , Ligação Proteica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Infect Immun ; 72(10): 6068-75, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15385511

RESUMO

An apparent worldwide resurgence of invasive group A Streptococcus (GAS) infections remains unexplained. However, we recently demonstrated in mice that when an otherwise nonlethal intranasal GAS infection is preceded by a nonlethal influenza A virus (IAV) infection, induction of lethal invasive GAS infections is often the result. In the present study, we established several isogenic mutants from a GAS isolate and evaluated several virulence factors as candidates responsible for the induction of invasive GAS infections. Disruption of the synthesis of the capsule, Mga, streptolysin O, streptolysin S, or streptococcal pyrogenic exotoxin B of GAS significantly reduced mortality among mice superinfected with IAV and a mutant. In addition, the number of GAS organisms adhering to IAV-infected alveolar epithelial cells was markedly reduced with the capsule-depleted mutant, although this was not the case with the other mutants. Wild-type GAS was found to bind directly to IAV particles, whereas the nonencapsulated mutant showed much less ability to bind. These results suggest that the capsule plays a key role in the invasion of host tissues by GAS following superinfection with IAV and GAS.


Assuntos
Aderência Bacteriana , Cápsulas Bacterianas/fisiologia , Células Epiteliais/microbiologia , Células Epiteliais/virologia , Streptococcus pyogenes/fisiologia , Superinfecção/microbiologia , Superinfecção/virologia , Animais , Cápsulas Bacterianas/química , Cápsulas Bacterianas/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Células Epiteliais/patologia , Feminino , Genes Bacterianos/genética , Humanos , Vírus da Influenza A/fisiologia , Influenza Humana/complicações , Influenza Humana/microbiologia , Influenza Humana/virologia , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese/genética , Mutação/genética , Ácido N-Acetilneuramínico/metabolismo , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/virologia , Streptococcus pyogenes/classificação , Streptococcus pyogenes/genética , Streptococcus pyogenes/patogenicidade , Superinfecção/complicações , Taxa de Sobrevida , Virulência
13.
Vaccine ; 22(25-26): 3404-10, 2004 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-15308365

RESUMO

Twenty-two and 37 infants and young children received two doses of influenza HA vaccine before the 2001-2002 influenza season and before the 2002-2003 season, respectively. Two or three serial specimens were obtained, before and 1 month after the first vaccination as well as 1 month after the second vaccination. Infants showed a significantly poor HI antibody rise and lymphocyte response compared with young children aged > or =12 months. Time kinetics of the lymphoproliferative responses to influenza antigen among young children varied whereas their activities in infants were typically negative before immunization and increased after vaccination. Infants responded poorly to HA influenza vaccine compared with young children.


Assuntos
Envelhecimento/imunologia , Imunidade Celular/imunologia , Vacinas contra Influenza/imunologia , Adulto , Anticorpos Antivirais/análise , Anticorpos Antivirais/biossíntese , Especificidade de Anticorpos , Pré-Escolar , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Imunidade Celular/fisiologia , Esquemas de Imunização , Lactente , Japão , Cinética , Contagem de Linfócitos , Linfócitos/imunologia , Masculino
14.
J Virol ; 77(7): 4104-12, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12634369

RESUMO

The apparent worldwide resurgence of invasive Streptococcus pyogenes infection in the last two decades remains unexplained. At present, animal models in which toxic shock-like syndrome or necrotizing fasciitis is induced after S. pyogenes infection are not well developed. We demonstrate here that infection with a nonlethal dose of influenza A virus 2 days before intranasal infection with a nonlethal dose of S. pyogenes strains led to a death rate of more than 90% in mice, 10% of which showed necrotizing fasciitis. Infection of lung alveolar epithelial cells by the influenza A virus resulted in viral hemagglutinin expression on the cell surface and promoted internalization of S. pyogenes. However, treatment with monoclonal antibodies to hemagglutinin markedly decreased this internalization. Our results indicate that prior infection with influenza A virus induces a lethal synergism, resulting in the induction of invasive S. pyogenes infection in mice.


Assuntos
Vírus da Influenza A/patogenicidade , Influenza Humana/complicações , Infecções Estreptocócicas/etiologia , Streptococcus pyogenes/patogenicidade , Superinfecção/etiologia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Antivirais/farmacologia , Linhagem Celular , Fasciite Necrosante/etiologia , Fasciite Necrosante/patologia , Feminino , Hemaglutininas Virais/metabolismo , Humanos , Influenza Humana/patologia , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia , Infecções Estreptocócicas/virologia , Superinfecção/microbiologia , Superinfecção/patologia , Superinfecção/virologia , Fator de Necrose Tumoral alfa/metabolismo , Virulência
15.
J Gen Virol ; 82(Pt 9): 2169-2172, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514726

RESUMO

To study the neutralizing epitopes of influenza B virus Victoria group strains, two monoclonal antibodies (MAbs) were used to select antigenic variants of the virus. MAbs 10B8 and 8E6 were found to react with B/Victoria group strains in three tests, peroxidase-antiperoxidase staining, haemagglutination inhibition and neutralization tests; no reactivity with B/Yamagata group strains was observed. Analysis of the deduced amino acid sequences of 10B8-induced variants identified a single amino acid deletion at residue 165 or 170, as well as a single amino acid substitution at residues 164 (Asp-->Tyr), 165 (Asn-->Ser or Thr) or 203 (Lys-->Thr or Asn). A single amino acid substitution at residue 241 (Pro-->Ser) was observed in 8E6-induced variants. Three-dimensional analysis showed that the epitopes for both MAbs were situated in close proximity to each other. Since B/Yamagata group strains are characterized by amino acid deletions at residues 164-166, the epitope for MAb 10B8 is strictly specific for B/Victoria group strains.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza B/imunologia , Animais , Anticorpos Monoclonais/imunologia , Sequência de Bases , Epitopos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Técnicas Imunoenzimáticas , Vírus da Influenza B/classificação , Camundongos , Dados de Sequência Molecular , Testes de Neutralização , Relação Estrutura-Atividade
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