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1.
Clin Infect Dis ; 58(4): 573-87, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24253249

RESUMO

BACKGROUND: Children born at the start of the human immunodeficiency virus (HIV) epidemic and infected during the perinatal period are now young adults living with the virus. Naive T-lymphocyte restoration is essential for the maintenance of a diverse T-cell receptor repertoire and for immunity to pathogens. METHODS: The ANRS-EP38-IMMIP study included 93 patients infected with HIV type 1 (HIV-1) during the perinatal period. Naive CD4 (CD4N) and CD8 (CD8N) T lymphocytes and CD4 recent thymic emigrants (CD4RTE) were quantified in the peripheral blood by flow cytometry. Wilcoxon tests, Pearson correlation coefficients, and linear regressions were used to study their associations with HIV disease parameters. RESULTS: Median CD4N, CD8N, and CD4RTE percentages were 56% (interquartile range [IQR], 44-64), 31% (IQR, 22-44), and 79% (IQR, 74-83), respectively. The three T-lymphocyte subsets were positively correlated with CD4 T-cell count. Patients aviremic at the time of the study tended to have a lower CD4N percentage (55% vs 58%; P = .10), a significantly higher CD8N percentage (39% vs 22%; P < .0001), and a significantly lower CD4RTE percentage (77% vs 81%; P = .003) than viremic patients. In aviremic patients, CD4N percentages were positively associated with cumulative viremia over the last 10 years (r = 0.335; P = .01) and were significantly higher in patients harboring X4R5 viruses than in those harboring R5 viruses (61% vs 44%; P = .001). CONCLUSIONS: After at least 15 years of HIV infection, perinatally infected youths had preserved CD4N and CD4RTE levels. This persistence of high levels of thymic activity potentially compensating for the deleterious effects of current and past HIV replication is remarkable.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Subpopulações de Linfócitos/imunologia , Timo/imunologia , Adolescente , Feminino , Citometria de Fluxo , Infecções por HIV/virologia , Humanos , Contagem de Linfócitos , Masculino , Adulto Jovem
2.
J Infect Dis ; 208(2): 235-43, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23559464

RESUMO

BACKGROUND: The genotoxicity of zidovudine has been established in experimental models. The objective of the study was to identify genotoxicity markers in cord blood cells from newborns exposed in utero to antiretroviral (ARV) combinations containing zidovudine. METHODS: Cells were investigated by karyotyping and gene expression analysis of the CD34(+) hematopoietic stem/progenitor cell (HPC) compartment. RESULTS: Karyotyping of the cord blood cells from 15 ARV-exposed newborns and 12 controls revealed a higher proportion of aneuploid cells in the exposed group (median, 18.8% [interquartile range, 10.0%-26.7%] vs 6.6% [interquartile range, 3.1%-11.7%]; P < .001). All chromosomes were involved, with a random distribution of these alterations. Gene expression profiling of CD34(+) HPCs from 7 ARV-exposed and 6 control newborns revealed that >300 genes were significantly upregulated or downregulated by at least 1.5-fold in the exposed group (P < .05 for all comparisons). Significant alterations of genes involved in cell cycle control, mitotic checkpoints, and DNA repair were identified. Although this study does not allow discrimination between the roles of each of the 3 drugs, both cytogenetic and transcriptional findings are similar to those in cellular experiments that used zidovudine alone. CONCLUSIONS: The cord blood cells, including hematopoietic stem cells, from newborns exposed in utero to a zidovudine-based ARV combination present cytogenetic and transcriptional abnormalities compatible with DNA damage.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Sangue Fetal/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Zidovudina/efeitos adversos , Adulto , Antígenos CD34/genética , Antígenos CD34/metabolismo , Ciclo Celular/genética , Reparo do DNA/genética , Combinação de Medicamentos , Feminino , Sangue Fetal/citologia , Sangue Fetal/fisiologia , Perfilação da Expressão Gênica/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Cariotipagem/métodos , Troca Materno-Fetal/fisiologia , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/metabolismo , Complicações Infecciosas na Gravidez/virologia , Efeitos Tardios da Exposição Pré-Natal , Células-Tronco/metabolismo , Transcriptoma/genética , Adulto Jovem , Zidovudina/farmacocinética
3.
J Infect Dis ; 205(10): 1520-8, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22427678

RESUMO

BACKGROUND: Our aim was to study the impact of lifelong human immunodeficiency virus (HIV) disease history on the current immune and virological status of perinatally infected patients reaching adulthood. We evaluated blood cell-associated HIV DNA load as an indicator of cell-associated HIV reservoirs and an independent predictor of disease progression. METHODS: The ANRS-EP38-IMMIP Study included 93 patients aged 15-24 years who were infected with HIV during the perinatal period. HIV DNA load was quantified by real-time polymerase chain reaction. RESULTS: Eighty-five percent of patients were receiving highly active antiretroviral therapy (HAART), and HIV RNA was undetectable in the plasma of 75% of these patients. The median HIV DNA load was 2.84 (interquartile range, 2.51-3.16) log(10) copies per 10(6) peripheral blood mononuclear cells. In patients with viral suppression, HIV DNA load was independently associated with cumulative HIV RNA viremia over the last 5 years. HIV DNA load was negatively correlated with CD4 cell count in patients with active replication but not in those with undetectable HIV RNA. CONCLUSIONS: In perinatally infected youths who are successfully treated, sustained viral suppression is associated with a low HIV DNA load. The absence of association between current HIV DNA load and CD4 cell counts suggests that the unique physiological characteristics of pediatric infection persist after adolescence. CLINICAL TRIALS REGISTRATION: NCT01055873.


Assuntos
DNA Viral/sangue , Infecções por HIV/transmissão , HIV-1/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , Carga Viral , Adolescente , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Estudos de Coortes , Progressão da Doença , Feminino , Seguimentos , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Recém-Nascido , Masculino , Gravidez , RNA Viral/sangue , Reação em Cadeia da Polimerase em Tempo Real , Viremia , Adulto Jovem
4.
Protein Expr Purif ; 67(1): 35-40, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19393319

RESUMO

Epstein-Barr virus nuclear antigen 1 (EBNA1) is a viral protein required for stable replication and segregation of DNA episomes containing the Epstein-Barr virus (EBV) origin of replication, OriP. Overproduction of EBNA1 protein in Escherichia coli has previously been shown to be difficult due to the large number of codons in EBNA1 gene that are infrequently used in E. coli. Here we changed the 26 rare codons that are found among the first 78 codons of EBNA1 gene, and replaced them with codons that encode the same amino-acids but are abundant in E. coli. This led to a significant improvement of EBNA1 expression in a standard E. coli strain. Partial EBNA1 polypeptides of 11.5-16 kDa extending from the N-terminus to the second arginine and glycine-rich region were extremely abundant in the extract, however, resulting in a second limitation of the level of EBNA1 expression. EBNA1 was expressed as a fusion with a C-terminal six-histidine tag in order to get rid of the short polypeptides by Ni-NTA affinity purification, and salt conditions were used that allowed us to extract and purify EBNA1 without resorting to protein denaturing reagents. The purified protein was used in DNA-binding experiments with DNA fragments containing specific EBNA1 sites. The E. coli-expressed protein formed specific DNA-protein complexes that could be analyzed in polyacrylamide gels without showing the aggregation, or linking, phenomenon that is usually observed with EBNA1 expressed in eukaryotic cells. EBNA1 protein expressed in E. coli should therefore prove useful to further study the biochemical properties of this crucial Epstein-Barr virus protein.


Assuntos
DNA/metabolismo , Antígenos Nucleares do Vírus Epstein-Barr/isolamento & purificação , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Escherichia coli/genética , Herpesvirus Humano 4/genética , Clonagem Molecular , Códon/genética , Eletroforese em Gel de Poliacrilamida , Antígenos Nucleares do Vírus Epstein-Barr/genética , Desnaturação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo
5.
Pediatr Infect Dis J ; 33(12): 1237-45, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24945880

RESUMO

BACKGROUND: Antiretroviral treatment interruption (TI) is not recommended in HIV-infected children. We aimed to evaluate the context and consequences of TI in clinical practice. METHODS: We investigated the probability and risk factors of a first TI in the 483 children treated with combined ART (cART) in the ANRS French national pediatric cohort. Immunologic and virologic outcomes were compared between patients with TI (TI group) and those on continuous treatment (matched control group), from a baseline defined as the age at first interruption for the TI child and the corresponding age for the control child. RESULTS: At least one TI ≥ 3 months occurred in 42.4% of patients, at a median age of 8.0 years, for a median duration of 12.1 months. After cART initiation, the risk of TI was 7.0% (5.0-9.6) at 1 year and 30.3% (26.1-35.0) at 5 years and was higher for children starting treatment before 2000 and for children starting cART before 6 months of age. AIDS-free survival was similar, but severe immunosuppression occurred earlier in the TI group than in the control group (adjusted HR = 3.1; 1.0-9.1; P = 0.04). Four years after baseline, the proportion of patients with CD4% ≥ 25% was lower in the TI group than in the control group (52.0% vs. 72.0%; P < 0.01), even among children restarting cART at least 6 months earlier (aRR = 0.5; 0.3-0.9; P = 0.03). CONCLUSIONS: The risk of TI in clinical practice has decreased but remains high. In intent-to-treat analysis, TI was associated with a greater risk of subsequent immunosuppression, even after cART resumption.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Tolerância Imunológica , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , França , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Resultado do Tratamento , Carga Viral , Suspensão de Tratamento
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