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1.
Transfusion ; 56(3): 722-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26559806

RESUMO

BACKGROUND: The incidence of hepatitis E virus (HEV) infection in the Netherlands is high. Blood donors are not routinely screened for HEV infection, but since January 2013, donations used for the production of solvent/detergent (S/D)-treated plasma have been screened for HEV RNA. STUDY DESIGN AND METHODS: Donations were screened for HEV RNA in pools of 96 and 192 donations. In addition, all donations made between 60 days before and after each HEV RNA-positive donation were tested individually for HEV RNA and anti-HEV immunoglobulin G. RESULTS: The screening of 59,474 donations between January 2013 and December 2014 resulted in identification of 45 HEV RNA-positive donations (0.076%) from 41 donors. HEV RNA loads ranged from 80 to 2.3 × 10(6) IU/mL. The number of positive donations increased significantly over time (p = 0.03). Thirty-three of 90 donations made up to 60 days before or after HEV RNA-positive donations were positive when tested individually, while they had not been detected in the pool screening. The mean duration of HEV viremia in the healthy blood donor is estimated to be 68 days. CONCLUSION: The incidence of HEV infection in the Netherlands is high and increased during the study period. In 2013 and 2014, HEV RNA was detected in 1 per 762 donations intended for production of S/D plasma.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Vírus da Hepatite E/fisiologia , Hepatite E/epidemiologia , Hepatite E/patologia , Feminino , Vírus da Hepatite E/classificação , Vírus da Hepatite E/genética , Humanos , Incidência , Masculino , Países Baixos/epidemiologia , Filogenia , RNA Viral/genética , Estudos Soroepidemiológicos
2.
PLoS One ; 3(6): e2422, 2008 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-18560583

RESUMO

BACKGROUND: To address evolution of HIV-1 after transmission, we studied sequence dynamics in and outside predicted epitopes of cytotoxic T lymphocytes (CTL) in subtype B HIV-1 variants that were isolated from 5 therapy-naive horizontal HLA-disparate donor-recipient pairs from the Amsterdam Cohort Studies on HIV-1 infection and AIDS. METHODOLOGY/PRINCIPAL FINDINGS: In the first weeks after transmission, the majority of donor-derived mutations in and outside donor-HLA-restricted epitopes in Gag, Env, and Nef, were preserved in the recipient. Reversion to the HIV-1 subtype B consensus sequence of mutations in- and outside donor-HLA-restricted CTL epitopes, and new mutations away from the consensus B sequence mostly within recipient-HLA-restricted epitopes, contributed equally to the early sequence changes. In the subsequent period (1-2 years) after transmission, still only a low number of both reverting and forward mutations had occurred. During subsequent long-term follow-up, sequence dynamics were dominated by forward mutations, mostly (50-85%) in recipient-HLA-restricted CTL epitopes. At the end of long-term follow-up, on average 43% of the transmitted CTL escape mutations in donor-HLA-restricted epitopes had reverted to the subtype B consensus sequence. CONCLUSIONS/SIGNIFICANCE: The relatively high proportion of long-term preserved mutations after transmission points to a lack of back selection even in the absence of CTL pressure, which may lead to an accumulating loss of critical CTL epitopes. Our data are supportive for a continuous adaptation of HIV-1 to host immune pressures which may have implications for vaccine design.


Assuntos
Evolução Molecular , HIV-1/genética , Antígenos HLA/imunologia , Doadores de Tecidos , Sequência de Bases , Primers do DNA , Antígenos HLA/genética , Teste de Histocompatibilidade , Mutação , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/sangue
3.
J Infect Dis ; 197(6): 871-9, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18279072

RESUMO

The human leukocyte antigen (HLA) B57 allele and the closely related HLA-B5801 allele are overrepresented among human immunodeficiency virus type 1 (HIV-1)-infected individuals with a long-term nonprogressive clinical course of disease (known as "long-term nonprogressors" [LTNPs]). These alleles are, however, also present among individuals with normal disease progression (known as "progressors"). In a comparison of HLA-B57/5801-expressing progressors and LTNPs, we observed a similar prevalence of escape mutations in 4 Nef epitopes and a similar reactivity of CD8+ T cells against 3 of 4 of these epitopes and their autologous escape variants. However, LTNPs tended to have frequent and preserved CD8+ T cell interferon-gamma responses against the wild-type HW9 Nef epitope, whereas progressors did not maintain a specific CD8+ T cell response. This finding is in line with the findings of a more exhausted phenotype of CD8+ T cells in progressors, as is demonstrated by their enhanced level of expression of inhibitory receptor "programmed death 1" (PD-1). The results of the present study suggest that preservation of HW9-specific T cell responses is associated with a more benign clinical course of infection.


Assuntos
Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Antígenos HLA-B/biossíntese , Linfócitos T Citotóxicos/imunologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana/imunologia , Antígenos CD/biossíntese , Antígenos CD/imunologia , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/imunologia , Contagem de Linfócito CD4 , Estudos de Coortes , Epitopos de Linfócito T/genética , Infecções por HIV/genética , Infecções por HIV/virologia , Sobreviventes de Longo Prazo ao HIV , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Humanos , Receptor de Morte Celular Programada 1 , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética
4.
J Immunol ; 179(5): 3133-43, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17709528

RESUMO

HLA B57 and the closely related HLA B5801 are over-represented among HIV-1 infected long-term nonprogressors (LTNPs). It has been suggested that this association between HLA B57/5801 and asymptomatic survival is a consequence of strong CTL responses against epitopes in the viral Gag protein. Moreover, CTL escape mutations in Gag would coincide with viral attenuation, resulting in low viral load despite evasion from immune control. In this study we compared HLA B57/5801 HIV-1 infected progressors and LTNPs for sequence variation in four dominant epitopes in Gag and their ability to generate CTL responses against these epitopes and the autologous escape variants. Prevalence and appearance of escape mutations in Gag epitopes and potential compensatory mutations were similar in HLA B57/5801 LTNPs and progressors. Both groups were also indistinguishable in the magnitude of CD8+ IFN-gamma responses directed against the wild-type or autologous escape mutant Gag epitopes in IFN-gamma ELISPOT analysis. Interestingly, HIV-1 variants from HLA B57/5801 LTNPs had much lower replication capacity than the viruses from HLA B57/5801 progressors, which did not correlate with specific mutations in Gag. In conclusion, the different clinical course of HLA B57/5801 LTNPs and progressors was not associated with differences in CTL escape mutations or CTL activity against epitopes in Gag but rather with differences in HIV-1 replication capacity.


Assuntos
Infecções por HIV/diagnóstico , HIV-1/fisiologia , Linfócitos T Citotóxicos/imunologia , Replicação Viral , Linfócitos T CD8-Positivos/imunologia , Progressão da Doença , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Produtos do Gene gag/genética , Produtos do Gene gag/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , Antígenos HLA-B/análise , Humanos , Tolerância Imunológica , Interferon gama/metabolismo , Masculino , Mutação , Linfócitos T Citotóxicos/virologia
5.
AIDS ; 18(14): 1925-31, 2004 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-15353978

RESUMO

OBJECTIVE: To study the effect of mycophenolate mofetil (MMF) on the decay rate of plasma HIV-1 RNA and the latently infected cellular reservoir in treatment-naive patients starting antiretroviral therapy. DESIGN: : Randomized trial. METHODS: A group of 19 HIV-1 infected patients (9 with a chronic and 10 with a primary infection) starting a triple antiretroviral drug regimen were randomized to a group with or without MMF. Plasma samples for HIV-1 RNA were taken and HLA-DR-CD4+ T cells were co-cultured for HIV-1 isolation. Slopes of plasma HIV-1 RNA and cellular viral load decay were calculated for the first 14 days and the first 24 weeks of treatment, respectively. RESULTS: The median plasma HIV-1 RNA daily decay rate in chronically infected patients was 0.25 log10 copies/ml [interquartile range (IQR), 0.18-0.30] with MMF and 0.28 log10 copies/ml (IQR, 0.22-0.32) without MMF (P = 0.56); in primary infected patients, it was 0.31 log10 copies/ml (IQR, 0.31-0.32) with MMF and 0.32 log10 copies/ml (IQR, 0.26-0.34) without MMF (P = 0.75). The median daily decay rate of latently infected cells was 0.017 and 0.004 infected cells/10 cells in patients with and without MMF, respectively (P = 0.89). The increase in CD4 T cells was comparable between patients with and without MMF. After stopping MMF, there was an increase in the cellular reservoir in six of eight patients. CONCLUSION: The addition of MMF to a triple class antiretroviral regimen in treatment-naive patients does not significantly increase the plasma HIV-1 RNA decay rate or the decay rate of the latently infected cellular reservoir.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Adulto , Terapia Antirretroviral de Alta Atividade , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue
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