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1.
J Clin Microbiol ; 55(7): 2180-2187, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28468860

RESUMO

Screening of blood for human T-cell lymphotropic virus type 1 and type 2 (HTLV-1 and -2, respectively) is important to diagnose and prevent infection and ensure the safety of blood supplies. The Elecsys HTLV-I/II assay is a newly developed, electrochemiluminescence screening assay for the detection of HTLV-1/2 infection. The sensitivity and specificity of the Elecsys HTLV-I/II assay were determined using well-characterized HTLV-1/2-positive serum and plasma samples and routine diagnostic and blood donor samples expected to be HTLV negative, respectively. These results were compared with those for at least one of the following CE-marked assays at seven independent laboratories and the Roche Diagnostics facility in Penzberg, Germany: Abbott Architect rHTLV-I/II, Ortho Avioq HTLV-I/II Microelisa system, Abbott Prism HTLV-I/HTLV-II, and DiaSorin Murex HTLV I+II. Fujirebio INNO-LIA HTLV-I/II Score was used as a confirmatory assay. The Elecsys HTLV-I/II, Abbott Architect rHTLV-I/II, and Abbott Prism HTLV-I/HTLV-II assays detected all HTLV-1/2-positive samples (sensitivity, 100%). Sensitivity for Ortho Avioq HTLV-I/II was 98.63%. The Elecsys HTLV-I/II assay had a specificity of 99.95% in blood donor samples, which was comparable to results for the other assays (range, 99.91 to 100%). In routine diagnostic samples, the specificity of the Elecsys HTLV-I/II assay was 99.83%, compared with 99.70% for Abbott Architect rHTLV-I/II. Specificity for the Elecsys HTLV-I/II assay in potentially cross-reactive samples was 100%, compared with 99.0% for Ortho Avioq HTLV-I/II and 99.2% for DiaSorin Murex HTLV I+II. The Elecsys HTLV-I/II assay has the sensitivity and specificity to support its use as a routine screening assay for detecting HTLV infection.


Assuntos
Sangue/virologia , Infecções por HTLV-I/diagnóstico , Infecções por HTLV-II/diagnóstico , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Programas de Rastreamento/métodos , Europa (Continente) , Humanos , Japão , Medições Luminescentes/métodos , Sensibilidade e Especificidade
2.
Vaccine ; 33(15): 1808-14, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25748336

RESUMO

BCG, the only licensed vaccine against tuberculosis (TB), provides geographically variable protection, an effect ascribed to exposure to environmental mycobacteria (EM). Here we show that altering the intestinal microbiota of mice by early-life infection with the commensal bacterium Helicobacter hepaticus (Hh) increases their susceptibility to challenge with Mycobacterium tuberculosis (Mtb). Furthermore Hh-infected mice immunised parenterally with the recombinant subunit vaccine, human adenovirus type 5 expressing the immunodominant antigen 85A of Mtb (Ad85A), display a reduced lung immune response and protection against Mtb challenge is also reduced. Expression of interleukin 10 (IL10) messenger RNA is increased in the colon of Hh infected mice. Treatment of Hh-infected Ad85A-immunised mice with anti-IL10 receptor antibody, following challenge with Mtb, restores the protective effect of the vaccine. These data show for the first time that alteration of the intestinal microbiota by addition of a single commensal organism can profoundly influence protection induced by a TB subunit vaccine via an IL10-dependent mechanism, a result with implications for the deployment of such vaccines in the field.


Assuntos
Microbioma Gastrointestinal , Infecções por Helicobacter/imunologia , Helicobacter hepaticus/fisiologia , Interleucina-10/imunologia , Vacinas contra a Tuberculose/imunologia , Adenovírus Humanos/genética , Administração Intranasal , Animais , Antígenos de Bactérias/imunologia , Carga Bacteriana , Colo/imunologia , Infecções por Helicobacter/microbiologia , Helicobacter hepaticus/crescimento & desenvolvimento , Humanos , Interleucina-10/genética , Pulmão/imunologia , Pulmão/patologia , Pulmão/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/patogenicidade , Tuberculose/prevenção & controle , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/imunologia
3.
J Immunol ; 193(5): 2306-16, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25070842

RESUMO

Tuberculosis remains a global health problem so that a more effective vaccine than bacillus Calmette-Guérin is urgently needed. Cytomegaloviruses persist lifelong in vivo and induce powerful immune and increasing ("inflationary") responses, making them attractive vaccine vectors. We have used an m1-m16-deleted recombinant murine CMV (MCMV) expressing Mycobacterium tuberculosis Ag 85A to show that infection of mice with this recombinant significantly reduces the mycobacterial load after challenge with M. tuberculosis, whereas control empty virus has a lesser effect. Both viruses induce immune responses to H-2(d)-restricted epitopes of MCMV pp89 and M18 Ags characteristic of infection with other MCMVs. A low frequency of 85A-specific memory cells could be revealed by in vivo or in vitro boosting or after challenge with M. tuberculosis. Kinetic analysis of M. tuberculosis growth in the lungs of CMV-infected mice shows early inhibition of M. tuberculosis growth abolished by treatment with NK-depleting anti-asialo ganglio-N-tetraosylceramide Ab. Microarray analysis of the lungs of naive and CMV-infected mice shows increased IL-21 mRNA in infected mice, whereas in vitro NK assays indicate increased levels of NK activity. These data indicate that activation of NK cells by MCMV provides early nonspecific protection against M. tuberculosis, potentiated by a weak 85A-specific T cell response, and they reinforce the view that the innate immune system plays an important role in both natural and vaccine-induced protection against M. tuberculosis.


Assuntos
Epitopos/imunologia , Vetores Genéticos , Muromegalovirus , Mycobacterium tuberculosis/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose Pulmonar/prevenção & controle , Animais , Epitopos/genética , Feminino , Antígeno de Histocompatibilidade H-2D/genética , Antígeno de Histocompatibilidade H-2D/imunologia , Interleucinas/genética , Interleucinas/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/genética , Vacinas contra a Tuberculose/genética , Tuberculose Pulmonar/genética , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia
4.
Infect Immun ; 81(11): 4149-59, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23980104

RESUMO

Neisseria meningitidis is a commensal of humans that can colonize the nasopharyngeal epithelium for weeks to months and occasionally invades to cause life-threatening septicemia and meningitis. Comparatively little is known about meningococcal gene expression during colonization beyond those first few hours. In this study, the transcriptome of adherent serogroup B N. meningitidis strain MC58 was determined at intervals during prolonged cocultivation with confluent monolayers of the human respiratory epithelial cell line 16HBE14. At different time points up to 21 days, 7 to 14% of the meningococcal genome was found to be differentially regulated. The transcriptome of adherent meningococci obtained after 4 h of coculture was markedly different from that obtained after prolonged cocultivation (24 h, 96 h, and 21 days). Genes persistently upregulated during prolonged cocultivation included three genes (hfq, misR/phoP, and lrp) encoding global regulatory proteins. Many genes encoding known adhesins involved in epithelial adherence were upregulated, including those of a novel locus (spanning NMB0342 to NMB0348 [NMB0342-NMB0348]) encoding epithelial cell-adhesive function. Sixteen genes (including porA, porB, rmpM, and fbpA) encoding proteins previously identified by their immunoreactivity to sera from individuals colonized long term with serogroup B meningococci were also upregulated during prolonged cocultivation, indicating that our system models growth conditions in vivo during the commensal state. Surface-expressed proteins downregulated in the nasopharynx (and thus less subject to selection pressure) but upregulated in the bloodstream (and thus vulnerable to antibody-mediated bactericidal activity) should be interesting candidate vaccine antigens, and in this study, three new proteins fulfilling these criteria have been identified: NMB0497, NMB0866, and NMB1882.


Assuntos
Células Epiteliais/microbiologia , Neisseria meningitidis/crescimento & desenvolvimento , Neisseria meningitidis/genética , Transcriptoma , Aderência Bacteriana , Linhagem Celular , Genes Bacterianos , Humanos , Estudos Longitudinais , Neisseria meningitidis/fisiologia , Fatores de Tempo , Fatores de Virulência/biossíntese
5.
Vaccine ; 31(41): 4624-31, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23896422

RESUMO

To test the relative efficacy of CD4 and CD8T cells in mediating protective immunity to Mycobacterium tuberculosis (Mtb), we compared three immunization regimes designed to induce preferentially each subset. BALB/c mice were immunized intranasally (i.n.) or parenterally with antigen 85A either in a recombinant Adenoviral vector (Ad85A), as recombinant protein (r85A) or as a set of overlapping 15mer peptides (p85A). For the first time we show that i.n. immunization with overlapping 85A synthetic peptides as well as Ad85A or r85A can provide protection against Mtb challenge. For all forms of the antigen, i.n. induces greater protection against Mtb challenge than parenteral immunization. Ad85A induces a predominantly CD8T cell response against the 85A(70-78) epitope, r85A a CD4 response to 85A(99-118) and p85A a balanced CD4/CD8 response to the CD4 85A(99-118 )and CD8 85A(145-152) epitopes. Immune responses to CD4 85A(99-118) and CD8 85A(70-78) but not CD8 85A(145-152) are protective. Although Ad85A induces a strong response to the protective CD8 85A(70-78) epitope, we could not induce any response to this epitope by peptide immunization. These results show that although peptide immunization can induce protective immunity to Mtb challenge, it can also induce a response to a non-protective epitope in antigen 85A, indicating that the specificity of an immune response may be more important for protection against Mtb than its magnitude. These findings have important implications for the application of such vaccines in humans.


Assuntos
Aciltransferases/imunologia , Antígenos de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose/prevenção & controle , Aciltransferases/administração & dosagem , Administração Intranasal , Animais , Antígenos de Bactérias/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Epitopos de Linfócito T/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Vacinas contra a Tuberculose/administração & dosagem , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
6.
Future Microbiol ; 6(7): 721-3, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21797686

RESUMO

The aim of the meeting was to consider the latest advances in meningitis, covering epidemiology, pathogenic mechanisms, host-interactive biology and vaccines in a variety of bacteria, fungi and protozoa that cause meningitis. The program was comprised of speakers from the UK, as well as international presenters, who had been invited and offered selected papers. Owing to space limitations, only the four bacteria with multiple invited speakers will be considered here.


Assuntos
Meningite/tratamento farmacológico , Meningite/epidemiologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/patologia , Infecções Bacterianas/prevenção & controle , Humanos , Meningite/patologia , Meningite/prevenção & controle , Micoses/tratamento farmacológico , Micoses/epidemiologia , Micoses/patologia , Micoses/prevenção & controle , Infecções por Protozoários/tratamento farmacológico , Infecções por Protozoários/epidemiologia , Infecções por Protozoários/patologia , Infecções por Protozoários/prevenção & controle , Reino Unido
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