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1.
Haematologica ; 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841782

RESUMO

Non-Hodgkin lymphomas (NHL) commonly occur in immune-deficient (ID) patients, both HIV-infected and transplanted, and are often EBV-driven with cerebral localization, raising the question of tumor immunogenicity, a critical issue for treatment responses. We investigated the immunogenomics of 68 lymphoproliferative disorders from 51 ID (34 posttransplant, 17 HIV+) and 17 immunocompetent patients. Overall, 72% were Large B Cells Lymphoma (LBCL) and 25% were primary central-nervous-system lymphoma (PCNSL) while 40% were EBV-positive. Tumor whole-exome and RNA sequencing, along with a bioinformatics pipeline allowed analysis of tumor mutational burden (TMB), tumor landscape and microenvironment (TME) and prediction of tumor neoepitopes. Both TMB (2.2 vs 3.4/Mb, p=0.001) and neoepitopes numbers (40 vs 200, p=0.00019) were lower in EBVpositive than in EBV-negative NHL, regardless of the immune status. In contrast both EBV and the immune status influenced the tumor mutational profile, with HNRNPF and STAT3 mutations exclusively observed in EBV-positive and ID NHL, respectively. Peripheral blood T-cell responses against tumor neoepitopes were detected in all EBV-negative cases but in only half EBV-positive ones, including responses against IgH-derived MHC-class-II restricted neoepitopes. The TME analysis showed higher CD8 T cell infiltrates in EBVpositive vs EBV-negative NHL, together with a more tolerogenic profile composed of Tregs, type-M2 macrophages and an increased expression of negative immune-regulators. Our results highlight that the immunogenomics of NHL in patients with immunodeficiency primarily relies on the tumor EBV status, while T cell recognition of tumor- and IgH-specific neoepitopes is conserved in EBV-negative patients, offering potential opportunities for future T cell-based immune therapies.

2.
J Immunol ; 207(5): 1333-1343, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34408012

RESUMO

Zika virus (ZIKV) is a mosquito-borne flavivirus that has emerged as a global concern because of its impact on human health. ZIKV infection during pregnancy can cause microcephaly and other severe brain defects in the developing fetus and there have been reports of the occurrence of Guillain-Barré syndrome in areas affected by ZIKV. NK cells are activated during acute viral infections and their activity contributes to a first line of defense because of their ability to rapidly recognize and kill virus-infected cells. To provide insight into NK cell function during ZIKV infection, we have profiled, using mass cytometry, the NK cell receptor-ligand repertoire in a cohort of acute ZIKV-infected female patients. Freshly isolated NK cells from these patients contained distinct, activated, and terminally differentiated, subsets expressing higher levels of CD57, NKG2C, and KIR3DL1 as compared with those from healthy donors. Moreover, KIR3DL1+ NK cells from these patients produced high levels of IFN-γ and TNF-α, in the absence of direct cytotoxicity, in response to in vitro stimulation with autologous, ZIKV-infected, monocyte-derived dendritic cells. In ZIKV-infected patients, overproduction of IFN-γ correlated with STAT-5 activation (r = 0.6643; p = 0.0085) and was mediated following the recognition of MHC class 1-related chain A and chain B molecules expressed by ZIKV-infected monocyte-derived dendritic cells, in synergy with IL-12 production by the latter cells. Together, these findings suggest that NK cells contribute to the generation of an efficacious adaptive anti-ZIKV immune response that could potentially affect the outcome of the disease and/or the development of persistent symptoms.


Assuntos
Células Matadoras Naturais/imunologia , Infecção por Zika virus/imunologia , Zika virus/fisiologia , Doença Aguda , Células Cultivadas , Estudos de Coortes , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-12/metabolismo , Ativação Linfocitária , Gravidez , Receptores KIR3DL1/metabolismo , Fator de Transcrição STAT5/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
Clin Infect Dis ; 73(11): e4214-e4222, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34355738

RESUMO

BACKGROUND: Early combined antiretroviral therapy (cART) limits the total HIV-DNA load in children. However, data on its impact in older children and adolescents remain scarce. This study compares HIV reservoirs in children (5-12 years) and adolescents (13-17 years) who started cART <6 months (early [E-] group) or >2 years (late [L-] group). METHODS: The ANRS-EP59-CLEAC study prospectively enrolled 76 patients perinatally infected with HIV-1 who reached HIV-RNA <400 copies/mL <24 months after cART initiation, regardless of subsequent viral suppression (E-group: 27 children, 9 adolescents; L-group: 19 children, 21 adolescents). Total and integrated HIV-DNA were quantified in blood and in CD4+ T-cell subsets. A substudy assessed HIV reservoir inducibility after ex vivo peripheral blood mononuclear cell (PBMC) stimulation. RESULTS: Total HIV-DNA levels were lower in early- versus late-treated patients (children: 2.14 vs 2.87 log copies/million PBMCs; adolescents: 2.25 vs 2.74 log; P < .0001 for both). Low reservoir was independently associated with treatment precocity, protective HLA, and low cumulative viremia since cART initiation. The 60 participants with undetectable integrated HIV-DNA started cART earlier than other patients (4 vs 54 months; P = .03). In those with sustained virological control, transitional and effector memory CD4+ T cells were less infected in the E-group than in the L-group (P = .03 and .02, respectively). Viral inducibility of reservoir cells after normalization to HIV-DNA levels was similar between groups. CONCLUSIONS: Early cART results in a smaller blood HIV reservoir until adolescence, but all tested participants had an inducible reservoir. This deserves cautious consideration for HIV remission strategies.


Assuntos
Infecções por HIV , HIV-1 , Adolescente , Terapia Antirretroviral de Alta Atividade/métodos , Criança , DNA Viral , Infecções por HIV/tratamento farmacológico , Humanos , Leucócitos Mononucleares , Carga Viral
4.
PLoS Pathog ; 15(5): e1007758, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31095640

RESUMO

The low pathogenicity and replicative potential of HIV-2 are still poorly understood. We investigated whether HIV-2 reservoirs might follow the peculiar distribution reported in models of attenuated HIV-1/SIV infections, i.e. limited infection of central-memory CD4 T lymphocytes (TCM). Antiretroviral-naive HIV-2 infected individuals from the ANRS-CO5 (12 non-progressors, 2 progressors) were prospectively included. Peripheral blood mononuclear cells (PBMCs) were sorted into monocytes and resting CD4 T-cell subsets (naive [TN], central- [TCM], transitional- [TTM] and effector-memory [TEM]). Reactivation of HIV-2 was tested in 30-day cultures of CD8-depleted PBMCs. HIV-2 DNA was quantified by real-time PCR. Cell surface markers, co-receptors and restriction factors were analyzed by flow-cytometry and multiplex transcriptomic study. HIV-2 DNA was undetectable in monocytes from all individuals and was quantifiable in TTM from 4 individuals (median: 2.25 log10 copies/106 cells [IQR: 1.99-2.94]) but in TCM from only 1 individual (1.75 log10 copies/106 cells). HIV-2 DNA levels in PBMCs (median: 1.94 log10 copies/106 PBMC [IQR = 1.53-2.13]) positively correlated with those in TTM (r = 0.66, p = 0.01) but not TCM. HIV-2 reactivation was observed in the cells from only 3 individuals. The CCR5 co-receptor was distributed similarly in cell populations from individuals and donors. TCM had a lower expression of CXCR6 transcripts (p = 0.002) than TTM confirmed by FACS analysis, and a higher expression of TRIM5 transcripts (p = 0.004). Thus the low HIV-2 reservoirs differ from HIV-1 reservoirs by the lack of monocytic infection and a limited infection of TCM associated to a lower expression of a potential alternative HIV-2 co-receptor, CXCR6 and a higher expression of a restriction factor, TRIM5. These findings shed new light on the low pathogenicity of HIV-2 infection suggesting mechanisms close to those reported in other models of attenuated HIV/SIV infection models.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Proteínas de Transporte/metabolismo , Infecções por HIV/metabolismo , HIV-2/imunologia , Memória Imunológica/imunologia , Leucócitos Mononucleares/metabolismo , Receptores CXCR6/metabolismo , Adulto , Idoso , Fatores de Restrição Antivirais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Proteínas de Transporte/genética , Estudos de Casos e Controles , Células Cultivadas , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-2/genética , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Receptores CXCR6/genética , Transcriptoma , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases
5.
Rheumatology (Oxford) ; 59(9): 2282-2286, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31846040

RESUMO

OBJECTIVES: Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that are important for antibacterial immunity and may have regulatory roles. MAIT cells are decreased during SLE. However, their frequencies and phenotype have not been investigated in DM. We studied MAIT cell frequencies and phenotype in DM patients with active and inactive disease (after treatment). METHODS: Peripheral blood flow cytometry analysis of MAIT cells was compared between DM (n = 22), SLE (n = 10), psoriasis (n = 7) and atopic dermatitis (n = 5) patients, and healthy controls (n = 19). RESULTS: A dramatic decrease of circulating MAIT cell frequency was observed in active DM and SLE patients compared with healthy controls and other inflammatory skin diseases [active DM: median = 0.25% (interquartile range 0.19-0.6%), P < 0.0001; active SLE: median = 0.61 (0.55-0.77), P < 0.0001 vs healthy controls: 2.32% (1.18-4.45%)]. MAIT cells from active DM patients had an abnormal phenotype including increased expression of CD25 and cytotoxic T-lymphocyte-associated protein 4 that correlated with their low frequency in the blood. CONCLUSION: In DM, peripheral blood MAIT cells are dramatically reduced and have an activated/exhausted phenotype that may be linked to increased activation-induced cell death.


Assuntos
Dermatomiosite/sangue , Células T Invariantes Associadas à Mucosa/metabolismo , Adulto , Dermatite Atópica/sangue , Feminino , Citometria de Fluxo , Humanos , Lúpus Eritematoso Sistêmico/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo , Psoríase/sangue , Índice de Gravidade de Doença
6.
J Infect Dis ; 215(11): 1684-1694, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28431019

RESUMO

Background: A simple test to identify recovery of CMV-specific T-cell immunity following hematopoietic stem cell transplantation (HSCT) could assist clinicians in managing CMV-related complications. Methods: In an observational, multicenter, prospective study of 94 HSCT recipients we evaluated CMV-specific T-cell immunity at baseline, 3, 6, 9, and 12 months after transplant using the Quantiferon-CMV, an enzyme-linked immunosorbent spot assay (ELISpot), and intracellular cytokine staining. Results: At 3 months after HSCT, participants who developed CMV disease (n = 8) compared with CMV reactivation (n = 26) or spontaneous viral control (n = 25) had significantly lower CD8+ T-cell production of interferon-γ (IFN-γ) in response to CMV antigens measured by Quantiferon-CMV (P = .0008). An indeterminate Quantiferon-CMV result had a positive predictive value of 83% and a negative predictive value of 98% for identifying participants at risk of further CMV reactivation. Participants experiencing CMV reactivation compared with patients without CMV reactivation had a reduced proportion of polyfunctional (IFN-γ+/tumor necrosis factor α-positive) CD4+ and CD8+ T cells and a higher proportion of interleukin 2-secreting cells (P = .01 and P = .002, respectively). Conclusions: Quantifying CMV-specific T-cell immunity after HSCT can identify participants at increased risk of clinically relevant CMV-related outcomes.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Testes de Liberação de Interferon-gama/métodos , Adolescente , Adulto , Idoso , Citomegalovirus/imunologia , Feminino , Humanos , Hospedeiro Imunocomprometido/imunologia , Interferon gama/análise , Interferon gama/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
7.
J Antimicrob Chemother ; 71(8): 2252-61, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27068399

RESUMO

OBJECTIVES: Boosted PIs are commonly prescribed in patients presenting with advanced HIV infection. We assessed the efficacy and tolerability of once-daily ritonavir-boosted atazanavir or darunavir plus two NRTIs in HIV-1-infected ART-naive patients with severe immunosuppression, targeting at least an 85% success rate at week 48. METHODS: This 48 week, open-label, non-comparative, randomized, multicentre trial included ART-naive patients with CD4 cell counts <200 cells/mm(3), with plasma HIV-1 RNA >1000 copies/mL and without genotypic mutations conferring resistance to the study drugs. Patients were randomized (1:1) to receive once-daily atazanavir/ritonavir (300/100 mg) or darunavir/ritonavir (800/100 mg) plus tenofovir disoproxil fumarate/emtricitabine or abacavir/lamivudine. The primary endpoint was treatment success, defined as plasma HIV-1 RNA ≤50 copies/mL at week 48 and no permanent PI/ritonavir discontinuation. The study was registered with ClinicalTrials.gov (NCT01928407). RESULTS: One hundred and twenty patients were enrolled: 77% were men, 30% were born in Africa and 39% had AIDS. The median baseline CD4 and plasma HIV-RNA values were 69 cells/mm(3) and 5.4 log10 copies/mL. All but four patients received tenofovir disoproxil fumarate/emtricitabine. The week 48 treatment success rate was 66% (95% CI 54%-78%) with atazanavir/ritonavir and 80% (95% CI 68%-89%) with darunavir/ritonavir. The median CD4 cell count increased similarly in the two groups (Δweek 48 to week 0: +194 cells/mm(3)). Adverse events occurred in 23 and 18 patients, respectively. CONCLUSIONS: Despite good adherence, neither study regimen reached the predefined objective, suggesting a need for more potent regimens for patients with advanced HIV infection.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Sulfato de Atazanavir/uso terapêutico , Darunavir/uso terapêutico , Infecções por HIV/tratamento farmacológico , Nucleosídeos/uso terapêutico , Ritonavir/uso terapêutico , Adulto , África , Idoso , Antirretrovirais/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Sulfato de Atazanavir/efeitos adversos , Contagem de Linfócito CD4 , Darunavir/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , HIV-1/efeitos dos fármacos , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Nucleosídeos/efeitos adversos , Ritonavir/efeitos adversos , Resultado do Tratamento , Carga Viral
8.
Retrovirology ; 12: 15, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25809376

RESUMO

BACKGROUND: CD8+ T cells recognize HIV-1 epitopes translated from a gene's primary reading frame (F1) and any one of its five alternative reading frames (ARFs) in the forward (F2, F3) or reverse (R1-3) directions. The 3' end of HIV-1's proviral coding strand contains a conserved sequence that is directly overlapping but antiparallel to the env gene (ARF R2) and encodes for a putative antisense HIV-1 protein called ASP. ASP expression has been demonstrated in vitro using HIV-transfected cell lines or infected cells. Although antibodies to ASP were previously detected in patient sera, T cell recognition of ASP-derived epitopes has not been evaluated. We therefore investigated the ex vivo and in vitro induction of ASP-specific T cell responses as a measure of immune recognition and protein expression during HIV-1 infection. RESULTS: A panel of overlapping peptides was initially designed from the full-length ASP sequence to perform a global assessment of T cell responses. Recognition of ASP-derived antigens was evaluated in an IFN-γELISpot assay using PBMCs from HIV-1 seropositive and seronegative individuals. Eight of 25 patients had positive responses to ASP antigens and none of the seronegative donors responded. As a complimentary approach, a second set of antigens was designed using HLA-I binding motifs and affinities. Two ASP-derived peptides with high predicted binding affinities for HLA-A*02 (ASP-YL9) and HLA-B*07 (ASP-TL10) were tested using PBMCs from HIV-1 seropositive and seronegative individuals who expressed the matching HLA-I-restricting allele. We found that HLA-I-restricted ASP peptides were only recognized by CD8+ T cells from patients with the relevant HLA-I and did not induce responses in any of the seronegative donors or patients who do not express the restrictive HLA alleles. Further, ASP-YL9-specific CD8+ T cells had functional profiles that were similar to a previously described HLA-A*02-restricted epitope (Gag-SL9). Specific recognition of ASP-YL9 by CD8+ T cells was also demonstrated by tetramer staining using cells from an HLA-A*02 HIV-infected patient. CONCLUSION: Our results provide the first description of CD8+ T cell-mediated immune responses to ASP in HIV-1-infected patients, demonstrating that ASP is expressed during infection. Our identification of epitopes within ASP has implications for designing HIV vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Expressão Gênica , Antígenos HIV/imunologia , HIV-1/imunologia , HIV-1/fisiologia , Proteínas Virais/imunologia , Replicação Viral , Adulto , Idoso , Células Cultivadas , Estudos de Coortes , ELISPOT , Feminino , Antígenos HIV/biossíntese , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas Virais/biossíntese
9.
J Antimicrob Chemother ; 70(7): 2108-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25900157

RESUMO

BACKGROUND: Therapeutic control of HIV replication reduces the size of the viral reservoir, particularly among central memory CD4+ T cells, and this effect might be accentuated by early treatment. METHODS: We examined the effect of ART initiated at the time of the primary HIV infection (early ART), lasting 2 and 6 years in 11 and 10 patients, respectively, on the HIV reservoir in peripheral resting CD4+ T cells, sorted into naive (TN), central memory (TCM), transitional memory (TTM) and effector memory (TEM) cells, by comparison with 11 post-treatment controllers (PTCs). RESULTS: Between baseline and 2 years, CD4+ T cell subset numbers increased markedly (P < 0.004) and HIV DNA levels decreased in all subsets (P < 0.009). TTM cells represented the majority of reservoir cells at both timepoints, T cell activation status normalized and viral diversity remained stable over time. The HIV reservoir was smaller after 6 years of early ART than after 2 years (P < 0.019), and did not differ between PTCs and patients treated for 6 years. One patient, who had low reservoir levels in all T cell subsets after 2 years of treatment similar to the levels in PTCs, spontaneously controlled viral replication during 18 months off treatment. CONCLUSIONS: Early prolonged ART thus limits the size of the HIV reservoir, protects long-lived cells from persistent infection and may enhance post-treatment control.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Prevenção Secundária/métodos , Adulto , Feminino , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
10.
J Immunol ; 191(2): 623-31, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23776176

RESUMO

Most vaccines, including those against influenza, were developed by focusing solely on humoral response for protection. However, vaccination activates different adaptive compartments that might play a role in protection. We took advantage of the pandemic 2009 A(H1N1) influenza vaccination to conduct a longitudinal integrative multiparametric analysis of seven immune parameters in vaccinated subjects. A global analysis underlined the predominance of induction of humoral and CD4 T cell responses, whereas pandemic 2009 A(H1N1)-specific CD8 responses did not improve after vaccination. A principal component analysis and hierarchical clustering of individuals showed a differential upregulation of influenza vaccine-specific immunity including hemagglutination inhibition titers, IgA(+) and IgG(+) Ab-secreting cells, effector CD4 or CD8 T cell frequencies at day 21 among individuals, suggesting a fine-tuning of the immune parameters after vaccination. This is related to individual factors including the magnitude and quality of influenza-specific immune responses before vaccination. We propose a graphical delineation of immune determinants that would be essential for a better understanding of vaccine-induced immunity in vaccination strategies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Anticorpos Antivirais/imunologia , Testes de Inibição da Hemaglutinação , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Análise de Componente Principal , Vacinação , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
11.
PLoS One ; 19(5): e0302684, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38722858

RESUMO

BACKGROUND: In most cases, Zika virus (ZIKV) causes a self-limited acute illness in adults, characterized by mild clinical symptoms that resolve within a few days. Immune responses, both innate and adaptive, play a central role in controlling and eliminating virus-infected cells during the early stages of infection. AIM: To test the hypothesis that circulating T cells exhibit phenotypic and functional activation characteristics during the viremic phase of ZIKV infection. METHODS: A comprehensive analysis using mass cytometry was performed on peripheral blood mononuclear cells obtained from patients with acute ZIKV infection (as confirmed by RT-PCR) and compared with that from healthy donors (HD). The frequency of IFN-γ-producing T cells in response to peptide pools covering immunogenic regions of structural and nonstructural ZIKV proteins was quantified using an ELISpot assay. RESULTS: Circulating CD4+ and CD8+ T lymphocytes from ZIKV-infected patients expressed higher levels of IFN-γ and pSTAT-5, as well as cell surface markers associated with proliferation (Ki-67), activation ((HLA-DR, CD38) or exhaustion (PD1 and CTLA-4), compared to those from HD. Activation of CD4+ and CD8+ memory T cell subsets, including Transitional Memory T Cells (TTM), Effector Memory T cells (TEM), and Effector Memory T cells Re-expressing CD45RA (TEMRA), was prominent among CD4+ T cell subset of ZIKV-infected patients and was associated with increased levels of IFN-γ, pSTAT-5, Ki-67, CTLA-4, and PD1, as compared to HD. Additionally, approximately 30% of ZIKV-infected patients exhibited a T cell response primarily directed against the ZIKV NS5 protein. CONCLUSION: Circulating T lymphocytes spontaneously produce IFN-γ and express elevated levels of pSTAT-5 during the early phase of ZIKV infection whereas recognition of ZIKV antigen results in the generation of virus-specific IFN-γ-producing T cells.


Assuntos
Linfócitos T CD8-Positivos , Interferon gama , Infecção por Zika virus , Zika virus , Humanos , Infecção por Zika virus/imunologia , Infecção por Zika virus/epidemiologia , Adulto , Zika virus/imunologia , Feminino , Masculino , Interferon gama/metabolismo , Interferon gama/imunologia , Brasil/epidemiologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD4-Positivos/imunologia , Pessoa de Meia-Idade , Adulto Jovem , Epidemias , Ativação Linfocitária/imunologia , Linfócitos T/imunologia
12.
J Exp Med ; 204(10): 2473-85, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17893201

RESUMO

The key attributes of CD8+ T cell protective immunity in human immunodeficiency virus (HIV) infection remain unclear. We report that CD8+ T cell responses specific for Gag and, in particular, the immunodominant p24 epitope KK10 correlate with control of HIV-1 replication in human histocompatibility leukocyte antigen (HLA)-B27 patients. To understand further the nature of CD8+ T cell-mediated antiviral efficacy, we performed a comprehensive study of CD8+ T cells specific for the HLA-B27-restricted epitope KK10 in chronic HIV-1 infection based on the use of multiparametric flow cytometry together with molecular clonotypic analysis and viral sequencing. We show that B27-KK10-specific CD8+ T cells are characterized by polyfunctional capabilities, increased clonal turnover, and superior functional avidity. Such attributes are interlinked and constitute the basis for effective control of HIV-1 replication. These data on the features of effective CD8+ T cells in HIV infection may aid in the development of successful T cell vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , HIV-1/fisiologia , Replicação Viral , Sequência de Aminoácidos , Antígenos CD57/metabolismo , Linfócitos T CD8-Positivos/patologia , Proliferação de Células , Senescência Celular , Produtos do Gene gag/imunologia , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Antígeno HLA-B27/química , Antígeno HLA-B27/imunologia , Humanos , Contagem de Linfócitos , Dados de Sequência Molecular
13.
Front Cell Infect Microbiol ; 13: 1165756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342247

RESUMO

Introduction: Increasing evidence has shown that coronavirus disease 19 (COVID-19) severity is driven by a dysregulated immunological response. Previous studies have demonstrated that natural killer (NK) cell dysfunction underpins severe illness in COVID-19 patients, but have lacked an in-depth analysis of NK cell markers as a driver of death in the most critically ill patients. Methods: We enrolled 50 non-vaccinated hospitalized patients infected with the initial virus or the alpha variant of SARS-CoV-2 with moderate or severe illness, to evaluate phenotypic and functional features of NK cells. Results: Here, we show that, consistent with previous studies, evolution NK cells from COVID-19 patients are more activated, with the decreased activation of natural cytotoxicity receptors and impaired cytotoxicity and IFN-γ production, in association with disease regardless of the SARS-CoV-2 strain. Fatality was observed in 6 of 17 patients with severe disease; NK cells from all of these patients displayed a peculiar phenotype of an activated memory-like phenotype associated with massive TNF-α production. Discussion: These data suggest that fatal COVID-19 infection is driven by an uncoordinated inflammatory response in part mediated by a specific subset of activated NK cells.


Assuntos
COVID-19 , Células Matadoras Naturais , SARS-CoV-2 , COVID-19/imunologia , COVID-19/patologia , COVID-19/fisiopatologia , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , SARS-CoV-2/classificação , SARS-CoV-2/fisiologia , Gravidade do Paciente , Evolução Fatal , Vacinas contra COVID-19 , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Receptores de Células Matadoras Naturais/metabolismo , Fator de Necrose Tumoral alfa , Ativação Linfocitária
14.
Clin Infect Dis ; 54(10): 1495-503, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22441653

RESUMO

BACKGROUND: The stable immune control of human immunodeficiency virus (HIV) in long-term nonprogressors (LTNPs) with protective human leukocyte antigen (HLA) alleles raises the question of whether and how these alleles influence the immune distribution of the HIV reservoirs. METHODS: Cell-associated HIV-DNA levels were quantified in blood sorted resting CD4 T-cell subsets from 8 LTNPs with and 10 without HLA-B*27 or HLA-B*57 alleles (HLA-B27/B57). RESULTS: A remarkably lower infection level of central memory CD4 T cells (T(CM)) was an exclusive feature that distinguished the HLA-B27/B57 HIV reservoirs from the other ones. In LTNPs, T(CM) protection was correlated with preservation of T(CM) counts, which correlated positively with the magnitude of HIV Gag-specific CD8 T cells. In HLA-B27/B57 LTNPs, a lower activation level of their memory CD4 T cells was associated with lower amounts of cell HIV-DNA in each resting memory CD4 subset and were also associated with higher ratios of HIV Gag-specific CD8 T cells per infected resting CD4 T cell (effector/target [E/T]). As a result, HLA-B27/B57 E/T ratios were negatively correlated with the contribution of memory CD4 T-cell subsets to the total HIV reservoirs. CONCLUSIONS: The potent antiviral immunity governed by the protective HLA-B27/B57 alleles, by limiting T(CM) infection and pool exhaustion, are associated with a reduced T(CM) contribution to the HIV reservoir.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Sobreviventes de Longo Prazo ao HIV , Antígenos HLA-B/genética , DNA Viral/isolamento & purificação , Antígenos HLA-B/imunologia , Humanos , Provírus/isolamento & purificação , Carga Viral
15.
J Hepatol ; 56(6): 1259-68, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22326469

RESUMO

BACKGROUND & AIMS: Immunity and genetic factors govern the recovery from acute hepatitis C virus (HCV) infection. No predictive factors have been yet identified in patients coinfected with the human immunodeficiency virus (HIV). We investigated whether early T cell responses to HCV producing transforming-growth-factor beta (TGF-ß) predict the outcome of acute HCV coinfection, independently of the IL-28B gene polymorphism. METHODS: Intracellular cytokine staining assays against HCV-core, E1, NS2, and NS4 overlapping peptides were used for the analysis of peripheral HCV-specific TGF-ß-producing T cells. Patients were genotyped for IL-28B polymorphisms. Healthy donors' samples were tested as controls. Twenty-four acute hepatitis C-HIV+ patients were followed-up for 15 months defining two groups: (A) Recovered (n=16, 5 spontaneous recoveries, 11 sustained virologic response after treatment), (B) Chronic HCV (n=8, 4 spontaneous chronic course, 4 therapeutic failures). RESULTS: During the acute pretreatment phase, core/NS2-specific TGF-ß-producing CD4+ and/or CD8+ T cells were detected in 8/24 (33%) patients. Lack of anti-HCV TGF-ß+ cells was characteristic of healthy donors and Group A, except for 2 cases, with frequencies significantly lower than in Group B (p=0.04 and 0.01), and was associated with recovery in 14/16 cases. Presence of anti-HCV TGF-ß+ cells was associated with persistent viremia in 6/8 cases (p=0.005). This profile remained stable over time. Such TGF-ß production was independent of the rs129679860 SNP (p=1.0) which was not associated with recovery (p=1.0). CONCLUSIONS: During acute hepatitis C, pre-therapeutic HCV-specific TGF-ß-producing T cells are a new marker independent of the IL-28B gene polymorphism, predicting the lack of spontaneous or therapeutic HCV clearance.


Assuntos
Coinfecção/virologia , Infecções por HIV/virologia , Hepatite C/imunologia , Linfócitos T/imunologia , Fator de Crescimento Transformador beta/biossíntese , Doença Aguda , Genótipo , Hepatite C/genética , Hepatite C/virologia , Humanos , Interferon gama/biossíntese , Interferons , Interleucina-17/biossíntese , Interleucinas/genética , Polimorfismo Genético
16.
J Med Virol ; 84(11): 1710-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22997073

RESUMO

The objective of the present study was to evaluate the virological efficacy of a 3-month short-course intensification with enfuvirtide (ENF) associated with an optimized background regimen (OBR) in treatment-experienced patients infected with HIV-1 with multiple therapeutic failures. This was a prospective, randomized, open-label multicenter trial including patients infected with HIV-1 and harboring a multi-resistant virus that was still susceptible to at least 2 active compounds. Patients were randomized (1:1) to receive OBR + ENF or OBR alone. ENF was discontinued at Week 12. The primary endpoint was the proportion of patients with plasma viral load <50 copies/ml at Week 24. Fifteen patients were randomized into the OBR group and 14 into the OBR + ENF group with a median viral load of 4.1 log(10) copies/ml and a median CD4+ cell count of 346 cells/mm(3) . The primary endpoint was achieved in 93% (14/15) and 79% (11/14) of patients, respectively. Eighty-seven percent (13/15) of patients had a viral load <50 copies/ml as soon as Week 12 in the OBR group and 79% (11/14) in the OBR + ENF group. At Week 12, the median CD4+ cell count was 327 in the OBR and 437 in the OBR + ENF groups and at Week 24 they were comparable. Intensification with ENF had no significant impact on PBMCs HIV-DNA levels. A 3-month short-course intensified treatment with ENF did not improve Week-24 virological response in treatment-experienced patients infected with HIV-1 harboring resistant viruses that were still susceptible to two antiretroviral drugs.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Proteína gp41 do Envelope de HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Terapia de Salvação/métodos , Adulto , Idoso , Enfuvirtida , Feminino , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Carga Viral
17.
Cells ; 11(6)2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35326466

RESUMO

The role of immune checkpoints (ICPs) in both anti-HIV T cell exhaustion and HIV reservoir persistence, has suggested that an HIV cure therapeutic strategy could involve ICP blockade. We studied the impact of anti-PD-1 therapy on HIV reservoirs and anti-viral immune responses in people living with HIV and treated for cancer. At several timepoints, we monitored CD4 cell counts, plasma HIV-RNA, cell associated (CA) HIV-DNA, EBV, CMV, HBV, HCV, and HHV-8 viral loads, activation markers, ICP expression and virus-specific T cells. Thirty-two patients were included, with median follow-up of 5 months. The CA HIV-DNA tended to decrease before cycle 2 (p = 0.049). Six patients exhibited a ≥0.5 log10 HIV-DNA decrease at least once. Among those, HIV-DNA became undetectable for 10 months in one patient. Overall, no significant increase in HIV-specific immunity was observed. In contrast, we detected an early increase in CTLA-4 + CD4+ T cells in all patients (p = 0.004) and a greater increase in CTLA-4+ and TIM-3 + CD8+ T cells in patients without HIV-DNA reduction compared to the others (p ≤ 0.03). Our results suggest that ICP replacement compensatory mechanisms might limit the impact of anti-PD-1 monotherapy on HIV reservoirs, and pave the way for combination ICP blockade in HIV cure strategies.


Assuntos
Infecções por HIV , Neoplasias , Antivirais/uso terapêutico , Antígeno CTLA-4 , Infecções por HIV/metabolismo , Humanos , Imunidade , Imunoterapia , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/metabolismo
18.
J Immunol ; 183(6): 3915-23, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19726768

RESUMO

Tuberculosis (TB)-associated immune restoration syndrome (IRS) is a frequent event (10 to 30%) in HIV-1-infected patients receiving antiretroviral treatment and is associated with an increased number of IFN-gamma-producing tuberculin-specific cells. To further understand the immune mechanisms of TB-IRS and to identify predictive factors, we prospectively analyzed the Th1 and TCRgammadelta T cells known to be involved in mycobacterial defenses and dendritic cells at baseline and after antiretroviral and TB treatment in 24 HIV-1(+) patients, 11 with and 13 without IRS. At baseline, these two groups differed by significantly lower proportions of TCRgammadelta and Vdelta2(+) T cells displaying the inhibitory receptors CD94/NKG2 and CD158ah,b in IRS patients. The two groups did not differ in the baseline characteristics of CD8 or CD4 T cells or TLR-2 expression on monocytes or myeloid/plasmacytoid dendritic cells. During IRS, the increase in tuberculin-specific IFN-gamma-producing cells involved only highly activated effector memory multifunctional (IFN-gamma(+)TNF-alpha(+)IL-2(-)) CD4 T cells, whereas activated HLA-DR(+) CD4(+) T cells also increased during IRS. In contrast, dendritic cells decreased significantly during IRS and there were no changes in TLR-2 expression. Finally, the Vdelta2(+) T cells, mostly killer Ig-related receptor (KIR) (CD94/NKG2(-) and CD158(-)), significantly peaked during IRS but not in non-IRS patients. In conclusion, IRS is associated with an increase in the number of activated tuberculin-specific effector memory CD4 T cells and of KIR(-)Vdelta2(+) TCRgammadelta(+) T cells. Higher proportions of Vdelta2(+)TCRgammadelta(+) T cells lacking KIR expression are present as baseline and distinguish patients who will develop IRS from those who will not.


Assuntos
Infecções por HIV/complicações , Síndrome Inflamatória da Reconstituição Imune/imunologia , Receptores de Antígenos de Linfócitos T gama-delta , Receptores KIR , Linfócitos T/imunologia , Tuberculina/imunologia , Tuberculose/imunologia , Adulto , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Estudos de Casos e Controles , Contagem de Células , Células Dendríticas , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Linfócitos T/microbiologia , Células Th1/imunologia
19.
AIDS Res Hum Retroviruses ; 37(3): 214-223, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33050708

RESUMO

Human immunodeficiency viruses induce rare attenuated diseases due either to HIV-1 in the exceptional long-term nonprogressors (LTNPs) or to HIV-2 in West Africa. To better understand characteristics of these two disease types we performed a multiplex comparative analysis of cell activation, exhaustion, and expression of coreceptors and restriction factors in CD4 T cells susceptible to harbor those viruses. We analyzed by flow cytometry the expression of HLA-DR, PD1, CCR5, CXCR6, SAMHD1, Blimp-1, and TRIM5α on CD4 T cell subsets from 10 HIV-1+ LTNPs and 14 HIV-2+ (12 nonprogressors and 2 progressors) of the ANRS CO-15 and CO-5 cohorts, respectively, and 12 HIV- healthy donors (HD). The V3 loop of the HIV-1 envelope from 6 HIV-1+ LTNPs was sequenced to determine the CXCR6-binding capacity. Proportions of HLA-DR+ and PD1+ cells were higher in memory CD4 T subsets from HIV-1 LTNPs compared with HIV-2 and HD. Similar findings were observed for CCR5+ cells although limited to central-memory CD4 T cell (TCM) and follicular helper T cell subsets, whereas all major subsets from HIV-1 LTNPs contained less CXCR6+ cells compared with HIV-2. All six V3 loop sequences from HIV-1 LTNPs contained a proline at position 326. Proportions of SAMHD1+ cells were higher in all resting CD4 T subsets from HIV-1 LTNPs compared with the other groups, whereas Blimp-1+ and Trim5α+ cells did not differ. The CD4 T cell subsets from HIV-1 LTNPs differ from those of HIV-2-infected subjects by higher levels of activation, exhaustion, and SAMHD1 expression that can reflect the distinct patterns of host/virus relationships.


Assuntos
Infecções por HIV , HIV-1 , Fatores de Restrição Antivirais , Linfócitos T CD4-Positivos , Sobreviventes de Longo Prazo ao HIV , HIV-2 , Humanos , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases
20.
J Exp Med ; 199(11): 1585-93, 2004 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15184506

RESUMO

Residual immunity to the smallpox virus raises key questions about the persistence of long-term immune memory in the absence of antigen, since vaccination ended in 1980. IFN-gamma-producing effector-memory and proliferative memory T cells were compared in 79 vaccinees 13-25 yr after their last immunization and in unvaccinated individuals. Only 20% of the vaccinees displayed both immediate IFN-gamma-producing effector-memory responses and proliferative memory responses at 6 d; 52.5% showed only proliferative responses; and 27.5% had no detectable vaccinia-specific responses at all. Both responses were mediated by CD4 and CD8 T cells. The vaccinia-specific IFN-gamma-producing cells were composed mainly of CD4Pos CD45RANeg CD11aHi CD27Pos and CCR7Neg T cells. Their frequency was low but could be expanded in vitro within 7 d. Time since first immunization affected their persistence: they vanished 45 yr after priming, but proliferative responses remained detectable. The number of recalls did not affect the persistence of residual effector-memory T cells. Programmed revaccination boosted both IFN-gamma and proliferative responses within 2 mo of recall, even in vaccinees with previously undetectable residual effector-memory cells. Such long-term maintenance of vaccinia-specific immune memory in the absence of smallpox virus modifies our understanding of the mechanism of persistence of long-term memory to poxviruses and challenges vaccination strategies.


Assuntos
Memória Imunológica , Interferon gama/biossíntese , Ativação Linfocitária , Vacina Antivariólica/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vacinação , Vaccinia virus/imunologia
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