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1.
Clin Infect Dis ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32067040

RESUMO

BACKGROUND: Immune control of Epstein-Barr virus (EBV) infection is impaired in HIV-infected individuals. We explored maternal factors associated with EBV acquisition in HIV-exposed uninfected (HEU) infants and the relationship between EBV infection and serious adverse events (SAE) during the first year of life. METHODS: Two hundred and one HEU infants from Uganda enrolled in the ANRS12174 trial were tested for anti-viral capsid antigen (VCA) antibodies at week 50 of life. The date of infection was estimated by testing of EBV DNA at weeks 1, 6, 14, 26, 38 and 50 postpartum on dried blood spot (DBS). RESULTS: Eighty-seven (43%) infants were tested positive for anti-VCA IgG at week 50. Among the 59 infants positive for EBV DNA, 25% were infected within the first 26 weeks. Almost half of them (12%) were infected before week 14. Shedding of EBV in breast milk was associated with EBV DNA in maternal plasma (P=.009), HIV RNA detection (P=.039), lower CD4 count (P=.001) and was correlated with plasma EBV DNA levels (P=.002). EBV infant infection at week 50 was associated with shedding of EBV in breast milk (P=.009) and young maternal age (P=.029). Occurrence of a clinical SAE, including malaria and pneumonia, was associated with higher levels of EBV DNA in infants (P=.010). CONCLUSIONS: By assessing EBV infection in HEU infants we observed that infection during the first year of life is determined by HIV and EBV maternal factors and that EBV DNA levels was higher among infants with clinical SAE.

2.
Oncoimmunology ; 10(1): 1853314, 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33457074

RESUMO

In this study we evaluated the potential of expanded NK cells (eNKs) from two sources combined with the mAbs daratumumab and pembrolizumab to target primary multiple myeloma (MM) cells ex vivo. In order to ascertain the best source of NK cells, we expanded and activated NK cells from peripheral blood (PB) of healthy adult donors and from umbilical cord blood (UCB). The resulting expanded NK (eNK) cells express CD16, necessary for carrying out antibody-dependent cellular cytotoxicity (ADCC). Cytotoxicity assays were performed on bone marrow aspirates of 18 MM patients and 4 patients with monoclonal gammopathy of undetermined significance (MGUS). Expression levels of PD-1 on eNKs and PD-L1 on MM and MGUS cells were also quantified. Results indicate that most eNKs obtained using our expansion protocol express a low percentage of PD-1+ cells. UCB eNKs were highly cytotoxic against MM cells and addition of daratumumab or pembrolizumab did not further increase their cytotoxicity. PB eNKs, while effective against MM cells, were significantly more cytotoxic when combined with daratumumab. In a minority of cases, eNK cells showed a detectable population of PD1+ cells. This correlated with low cytotoxic activity, particularly in UCB eNKs. Addition of pembrolizumab did not restore their activity. Results indicate that UCB eNKs are to be preferentially used against MM in the absence of daratumumab while PB eNKs have significant cytotoxic advantage when combined with this mAb.

3.
Front Immunol ; 10: 3026, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998309

RESUMO

The innate lymphocyte lineage natural killer (NK) is now the target of multiple clinical applications, although none has received an agreement from any regulatory agency yet. Transplant of naïve NK cells has not proven efficient enough in the vast majority of clinical trials. Hence, new protocols wish to improve their medical use by producing them from stem cells and/or modifying them by genetic engineering. These techniques have given interesting results but these improvements often hide that natural killers are mainly that: natural. We discuss here different ways to take advantage of NK physiology to improve their clinical activity without the need of additional modifications except for in vitro activation and expansion and allograft in patients. Some of these tactics include combination with monoclonal antibodies (mAb), drugs that change metabolism and engraftment of specific NK subsets with particular activity. Finally, we propose to use specific NK cell subsets found in certain patients that show increase activity against a specific disease, including the use of NK cells derived from patients.


Assuntos
Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Anticorpos Monoclonais/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Biomarcadores , Microambiente Celular/imunologia , Evolução Clonal , Citocinas/metabolismo , Humanos , Memória Imunológica , Antígenos Comuns de Leucócito/metabolismo , Ativação Linfocitária/imunologia
4.
Epilepsia ; 59(1): 123-134, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29125184

RESUMO

OBJECTIVE: Available evidence points to a role of cytochrome P450 (Cyp) drug biotransformation enzymes in central nervous system diseases, including epilepsy. Deviations in drug pharmacokinetic profiles may impact therapeutic outcomes. Here, we ask whether spontaneous recurrent seizure (SRS) activity is sufficient to modulate the expression of major Cyp enzymes in the liver and brain. METHODS: Unilateral intrahippocampal (IH) kainic acid (KA) injections were used to elicit nonconvulsive status epilepticus (SE), epileptogenesis, and SRS, as monitored by video-electroencephalography. Intraperitoneal (IP) KA injection was used to trigger generalized tonic-clonic SE. KA-injected mice and sham controls were sacrificed at 24-72 hours and 1 week post-SE (IH or IP KA), and during the chronic stage (SRS; 6 weeks post-IH KA). Liver and brain tissues were processed for histology, real-time quantitative polymerase chain reaction, Western blot, or microsomal enzymatic assay. Cyp2e1, Cyp3a13, glial fibrillary acidic protein (GFAP), IBA1, xenobiotic nuclear receptors nr1i2 (PXR), nr1i3 (CAR) and nr3c1 (glucocorticoid receptor [GR]) expression was examined. Serum samples were obtained to assay corticosterone levels, a GR activator. RESULTS: A significant increase of Cyp3a13 and Cyp2e1 transcript level and protein expression was found in the liver and hippocampi during SRS, as compared to control mice. In the ipsilateral hippocampus, Cyp2e1 and Cyp3a protein upregulation during SRS positively correlated to GFAP expression. GFAP+ , and not IBA1+ , cells colocalized with Cyp2e1 or Cyp3a expression. In the liver, a trend increase in Cyp3a microsomal activity was found during SRS as compared to control mice. The transcript levels of the Cyp upstream regulators GR, xenobiotic nr1i2, and nr1i3 receptors were unchanged at SRS. Corticosterone levels, a GR ligand, were increased in the blood post-SE. SIGNIFICANCE: SRS modifies Cyp expression in the liver and the hippocampus. Nuclear receptors or inflammatory pathways are candidate mechanisms of Cyp regulation during seizures.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Hipocampo/enzimologia , Fígado/enzimologia , Estado Epiléptico/enzimologia , Estado Epiléptico/patologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Corticosterona/sangue , Sistema Enzimático do Citocromo P-450/genética , Modelos Animais de Doenças , Vias de Administração de Medicamentos , Agonistas de Aminoácidos Excitatórios/toxicidade , Lateralidade Funcional/efeitos dos fármacos , Lateralidade Funcional/fisiologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/efeitos dos fármacos , Ácido Caínico/toxicidade , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Recidiva , Estatísticas não Paramétricas , Estado Epiléptico/sangue , Estado Epiléptico/induzido quimicamente , Fatores de Tempo
5.
PLoS One ; 12(8): e0183856, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850597

RESUMO

BACKGROUND: Viral load monitoring and early Epstein-Barr virus (EBV) DNA detection are essential in routine laboratory testing, especially in preemptive management of Post-transplant Lymphoproliferative Disorder. Targeting the repetitive BamHI-W sequence was shown to increase the sensitivity of EBV DNA quantification, but the variability of BamHI-W reiterations was suggested to be a source of quantification bias. We aimed to assess the extent of variability associated with BamHI-W PCR and its impact on the sensitivity of EBV DNA quantification using the 1st WHO international standard, EBV strains and clinical samples. METHODS: Repetitive BamHI-W- and LMP2 single- sequences were amplified by in-house qPCRs and BXLF-1 sequence by a commercial assay (EBV R-gene™, BioMerieux). Linearity and limits of detection of in-house methods were assessed. The impact of repeated versus single target sequences on EBV DNA quantification precision was tested on B95.8 and Raji cell lines, possessing 11 and 7 copies of the BamHI-W sequence, respectively, and on clinical samples. RESULTS: BamHI-W qPCR demonstrated a lower limit of detection compared to LMP2 qPCR (2.33 log10 versus 3.08 log10 IU/mL; P = 0.0002). BamHI-W qPCR underestimated the EBV DNA load on Raji strain which contained fewer BamHI-W copies than the WHO standard derived from the B95.8 EBV strain (mean bias: - 0.21 log10; 95% CI, -0.54 to 0.12). Comparison of BamHI-W qPCR versus LMP2 and BXLF-1 qPCR showed an acceptable variability between EBV DNA levels in clinical samples with the mean bias being within 0.5 log10 IU/mL EBV DNA, whereas a better quantitative concordance was observed between LMP2 and BXLF-1 assays. CONCLUSIONS: Targeting BamHI-W resulted to a higher sensitivity compared to LMP2 but the variable reiterations of BamHI-W segment are associated with higher quantification variability. BamHI-W can be considered for clinical and therapeutic monitoring to detect an early EBV DNA and a dynamic change in viral load.


Assuntos
DNA Viral , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Herpesvirus Humano 4/genética , Humanos , Sequências Repetitivas de Ácido Nucleico , Sensibilidade e Especificidade , Carga Viral
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