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1.
Nat Immunol ; 19(9): 973-985, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30127434

RESUMO

Human inborn errors of IFN-γ immunity underlie mycobacterial diseases. We describe patients with Mycobacterium bovis (BCG) disease who are homozygous for loss-of-function mutations of SPPL2A. This gene encodes a transmembrane protease that degrades the N-terminal fragment (NTF) of CD74 (HLA invariant chain) in antigen-presenting cells. The CD74 NTF therefore accumulates in the HLA class II+ myeloid and lymphoid cells of SPPL2a-deficient patients. This toxic fragment selectively depletes IL-12- and IL-23-producing CD1c+ conventional dendritic cells (cDC2s) and their circulating progenitors. Moreover, SPPL2a-deficient memory TH1* cells selectively fail to produce IFN-γ when stimulated with mycobacterial antigens in vitro. Finally, Sppl2a-/- mice lack cDC2s, have CD4+ T cells that produce small amounts of IFN-γ after BCG infection, and are highly susceptible to infection with BCG or Mycobacterium tuberculosis. These findings suggest that inherited SPPL2a deficiency in humans underlies mycobacterial disease by decreasing the numbers of cDC2s and impairing IFN-γ production by mycobacterium-specific memory TH1* cells.

3.
J Exp Med ; 213(13): 2931-2947, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27899441

RESUMO

The host responds to virus infection by activating type I interferon (IFN) signaling leading to expression of IFN-stimulated genes (ISGs). Dysregulation of the IFN response results in inflammatory diseases and chronic infections. In this study, we demonstrate that IFN regulatory factor 2 (IRF2), an ISG and a negative regulator of IFN signaling, influences alphavirus neuroinvasion and pathogenesis. A Sindbis virus strain that in wild-type (WT) mice only causes disease when injected into the brain leads to lethal encephalitis in Irf2-/- mice after peripheral inoculation. Irf2-/- mice fail to control virus replication and recruit immune infiltrates into the brain. Reduced B cells and virus-specific IgG are observed in the Irf2-/- mouse brains despite the presence of peripheral neutralizing antibodies, suggesting a defect in B cell trafficking to the central nervous system (CNS). B cell-deficient µMT mice are significantly more susceptible to viral infection, yet WT B cells and serum are unable to rescue the Irf2-/- mice. Collectively, our data demonstrate that proper localization of B cells and local production of antibodies in the CNS are required for protection. The work advances our understanding of host mechanisms that affect viral neuroinvasion and their contribution to immunity against CNS infections.


Assuntos
Infecções por Alphavirus/imunologia , Linfócitos B/imunologia , Encefalopatias/imunologia , Movimento Celular/imunologia , Fator Regulador 2 de Interferon/imunologia , Vírus Sindbis/imunologia , Infecções por Alphavirus/genética , Infecções por Alphavirus/patologia , Animais , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Linfócitos B/patologia , Encefalopatias/genética , Encefalopatias/patologia , Encefalopatias/virologia , Movimento Celular/genética , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Fator Regulador 2 de Interferon/genética , Camundongos , Camundongos Knockout
4.
J Exp Med ; 213(13): 2861-2870, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27864467

RESUMO

In humans, conventional dendritic cells (cDCs) exist as two unique populations characterized by expression of CD1c and CD141. cDCs arise from increasingly restricted but well-defined bone marrow progenitors that include the common DC progenitor that differentiates into the pre-cDC, which is the direct precursor of cDCs. In this study, we show that pre-cDCs in humans are heterogeneous, consisting of two distinct populations of precursors that are precommitted to become either CD1c+ or CD141+ cDCs. The two groups of lineage-primed precursors can be distinguished based on differential expression of CD172a. Both subpopulations of pre-cDCs arise in the adult bone marrow and can be found in cord blood and adult peripheral blood. Gene expression analysis revealed that CD172a+ and CD172a- pre-cDCs represent developmentally discrete populations that differentially express lineage-restricted transcription factors. A clinical trial of Flt3L injection revealed that this cytokine increases the number of both CD172a- and CD172a+ pre-cDCs in human peripheral blood.


Assuntos
Antígenos CD1/metabolismo , Antígenos de Superfície/metabolismo , Células Dendríticas/metabolismo , Regulação da Expressão Gênica/fisiologia , Glicoproteínas/metabolismo , Células-Tronco/metabolismo , Adulto , Antígenos de Diferenciação/biossíntese , Células Dendríticas/citologia , Humanos , Receptores Imunológicos/biossíntese , Células-Tronco/citologia , Tirosina Quinase 3 Semelhante a fms/metabolismo
6.
Nat Protoc ; 10(9): 1407-22, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26292072

RESUMO

Human dendritic cells (DCs) develop from progressively restricted bone marrow (BM) progenitors: these progenitor cells include granulocyte, monocyte and DC progenitor (GMDP) cells; monocyte and DC progenitor (MDP) cells; and common DC progenitor (CDP) and DC precursor (pre-DC) cells. These four DC progenitors can be defined on the basis of the expression of surface markers such as CD34 and hematopoietin receptors. In this protocol, we describe five multiparametric flow cytometry panels that can be used as a tool (i) to simultaneously detect or phenotype the four DC progenitors, (ii) to isolate DC progenitors to enable in vitro differentiation or (iii) to assess the in vitro differentiation and proliferation of DC progenitors. The entire procedure from isolation of cells to flow cytometry can be completed in 3-7 h. This protocol provides optimized antibody panels, as well as gating strategies, for immunostaining of BM and cord blood specimens to study human DC hematopoiesis in health, disease and vaccine settings.


Assuntos
Células Dendríticas/citologia , Citometria de Fluxo/métodos , Células-Tronco/citologia , Células da Medula Óssea/fisiologia , Diferenciação Celular , Humanos
7.
J Immunol Methods ; 425: 21-26, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26056939

RESUMO

Different dendritic cell (DC) subsets co-exist in humans and coordinate the immune response. Having a short life, DCs must be constantly replenished from their progenitors in the bone marrow through hematopoiesis. Identification of a DC-restricted progenitor in mouse has improved our understanding of how DC lineage diverges from myeloid and lymphoid lineages. However, identification of the DC-restricted progenitor in humans has not been possible because a system that simultaneously nurtures differentiation of human DCs, myeloid and lymphoid cells, is lacking. Here we report a cytokine and stromal cell culture that allows evaluation of CD34(+) progenitor potential to all three DC subsets as well as other myeloid and lymphoid cells, at a single cell level. Using this system, we show that human granulocyte-macrophage progenitors are heterogeneous and contain restricted progenitors to DCs.


Assuntos
Células Dendríticas/imunologia , Células-Tronco/imunologia , Células Estromais/imunologia , Antígenos CD34/imunologia , Medula Óssea/imunologia , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Células Cultivadas , Células Progenitoras de Granulócitos e Macrófagos/imunologia , Hematopoese/imunologia , Humanos , Linfócitos/imunologia
8.
J Exp Med ; 212(3): 401-13, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25687281

RESUMO

Two subsets of conventional dendritic cells (cDCs) with distinct cell surface markers and functions exist in mouse and human. The two subsets of cDCs are specialized antigen-presenting cells that initiate T cell immunity and tolerance. In the mouse, a migratory cDC precursor (pre-CDC) originates from defined progenitors in the bone marrow (BM). Small numbers of short-lived pre-CDCs travel through the blood and replace cDCs in the peripheral organs, maintaining homeostasis of the highly dynamic cDC pool. However, the identity and distribution of the immediate precursor to human cDCs has not been defined. Using a tissue culture system that supports the development of human DCs, we identify a migratory precursor (hpre-CDC) that exists in human cord blood, BM, blood, and peripheral lymphoid organs. hpre-CDCs differ from premonocytes that are restricted to the BM. In contrast to earlier progenitors with greater developmental potential, the hpre-CDC is restricted to producing CD1c(+) and CD141(+) Clec9a(+) cDCs. Studies in human volunteers demonstrate that hpre-CDCs are a dynamic population that increases in response to levels of circulating Flt3L.


Assuntos
Antígenos CD1/metabolismo , Antígenos de Superfície/metabolismo , Células Dendríticas/metabolismo , Glicoproteínas/metabolismo , Proliferação de Células , Sangue Fetal/citologia , Humanos , Células Progenitoras Linfoides/citologia , Células Progenitoras Linfoides/metabolismo , Tecido Linfoide/citologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/farmacologia , Técnicas de Cultura de Tecidos
9.
J Exp Med ; 212(3): 385-99, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25687283

RESUMO

In mice, two restricted dendritic cell (DC) progenitors, macrophage/dendritic progenitors (MDPs) and common dendritic progenitors (CDPs), demonstrate increasing commitment to the DC lineage, as they sequentially lose granulocyte and monocyte potential, respectively. Identifying these progenitors has enabled us to understand the role of DCs and monocytes in immunity and tolerance in mice. In humans, however, restricted monocyte and DC progenitors remain unknown. Progress in studying human DC development has been hampered by lack of an in vitro culture system that recapitulates in vivo DC hematopoiesis. Here we report a culture system that supports development of CD34(+) hematopoietic stem cell progenitors into the three major human DC subsets, monocytes, granulocytes, and NK and B cells. Using this culture system, we defined the pathway for human DC development and revealed the sequential origin of human DCs from increasingly restricted progenitors: a human granulocyte-monocyte-DC progenitor (hGMDP) that develops into a human monocyte-dendritic progenitor (hMDP), which in turn develops into monocytes, and a human CDP (hCDP) that is restricted to produce the three major DC subsets. The phenotype of the DC progenitors partially overlaps with granulocyte-macrophage progenitors (GMPs). These progenitors reside in human cord blood and bone marrow but not in the blood or lymphoid tissues.


Assuntos
Células Dendríticas/citologia , Sangue Fetal/citologia , Monócitos/citologia , Animais , Antígenos CD34/metabolismo , Medula Óssea , Células da Medula Óssea , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem da Célula , Regulação da Expressão Gênica , Granulócitos/citologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos Mutantes , Análise de Célula Única , Células Estromais/citologia
10.
Immunol Lett ; 161(1): 65-75, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24845157

RESUMO

CD86 and CD80, the ligands for the co-stimulatory molecules CD28 and CTLA-4, are members of the Ig superfamily. Their structure includes Ig variable-like (IgV) domains, Ig constant-like (IgC) domains and intracellular domains. Although crystallographic studies have clearly identified the IgV domain to be responsible for receptor interactions, earlier studies suggested that both Ig domains are required for full co-signaling function. Herein, we have used deletion and chimeric human CD80 and CD86 molecules in co-stimulation assays to study the impact of the multimeric state of IgV and IgC domains on receptor binding properties and on co-stimulatory function in a peptide-specific T cell activation model. We report for the first time the presence of CD80 dimers and CD86 monomers in living cells. Moreover, we show that the IgC domain of both molecules inhibits multimer formation and greatly affects binding to the co-receptors CD28 and CTLA-4. Finally, both IgC and intracellular domains are required for full co-signaling function. These findings reveal the distinct but complementary roles of CD80 and CD86 IgV and IgC domains in T cell activation.


Assuntos
Antígeno B7-1/química , Antígeno B7-1/metabolismo , Antígeno B7-2/química , Antígeno B7-2/metabolismo , Domínios e Motivos de Interação entre Proteínas , Estrutura Quaternária de Proteína , Transdução de Sinais , Antígeno B7-1/genética , Antígeno B7-2/genética , Antígenos CD28/metabolismo , Antígeno CTLA-4/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Citometria de Fluxo , Transferência Ressonante de Energia de Fluorescência , Humanos , Interleucina-2/biossíntese , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Ligação Proteica , Multimerização Proteica , Deleção de Sequência
11.
J Immunol ; 191(5): 2194-204, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23918986

RESUMO

Chronic activation of T cells is a hallmark of HIV-1 infection and plays an important role in disease progression. We previously showed that the engagement of the inhibitory receptor programmed death (PD)-1 on HIV-1-specific CD4(+) and CD8(+) T cells leads to their functional exhaustion in vitro. However, little is known about the impact of PD-1 expression on the turnover and maturation status of T cells during the course of the disease. In this study, we show that PD-1 is upregulated on all T cell subsets, including naive, central memory, and transitional memory T cells in HIV-1-infected subjects. PD-1 is expressed at similar levels on most CD4(+) T cells during the acute and the chronic phase of disease and identifies cells that have recently entered the cell cycle. In contrast, PD-1 expression is dramatically increased in CD8(+) T cells during the transition from acute to chronic infection, and this is associated with reduced levels of cell proliferation. The failure to downregulate expression of PD-1 in most T cells during chronic HIV-1 infection is associated with persistent alterations in the distribution of T cell subsets and is associated with impaired responses to IL-7. Our findings identify PD-1 as a marker for aberrant distribution of T cell subsets in HIV-1 infection.


Assuntos
Biomarcadores/análise , Infecções por HIV/imunologia , Receptor de Morte Celular Programada 1/imunologia , Subpopulações de Linfócitos T/imunologia , Citometria de Fluxo , Infecções por HIV/metabolismo , Humanos , Receptor de Morte Celular Programada 1/metabolismo , Subpopulações de Linfócitos T/metabolismo
12.
Nat Med ; 19(6): 730-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23685841

RESUMO

Innate sensing mechanisms trigger a variety of humoral and cellular events that are essential to adaptive immune responses. Here we describe an innate sensing pathway triggered by Plasmodium infection that regulates dendritic cell homeostasis and adaptive immunity through Flt3 ligand (Flt3l) release. Plasmodium-induced Flt3l release in mice requires Toll-like receptor (TLR) activation and type I interferon (IFN) production. We found that type I IFN supports the upregulation of xanthine dehydrogenase, which metabolizes the xanthine accumulating in infected erythrocytes to uric acid. Uric acid crystals trigger mast cells to release soluble Flt3l from a pre-synthesized membrane-associated precursor. During infection, Flt3l preferentially stimulates expansion of the CD8-α(+) dendritic cell subset or its BDCA3(+) human dendritic cell equivalent and has a substantial impact on the magnitude of T cell activation, mostly in the CD8(+) compartment. Our findings highlight a new mechanism that regulates dendritic cell homeostasis and T cell responses to infection.


Assuntos
Células Dendríticas/fisiologia , Malária/imunologia , Proteínas de Membrana/fisiologia , Linfócitos T/imunologia , Animais , Antígenos CD8/análise , Movimento Celular , Feminino , Humanos , Interferon Tipo I/fisiologia , Masculino , Mastócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores Toll-Like/fisiologia , Ácido Úrico/metabolismo , Ácido Úrico/farmacologia
13.
Blood ; 121(25): 5034-44, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23482932

RESUMO

Functional differences between human dendritic cell (DC) subsets and the potential benefits of targeting them with vaccines remain poorly defined. Here we describe that mice with reconstituted human immune system components (huNSG mice) develop all human conventional and plasmacytoid DC compartments in lymphoid organs. Testing different Toll-like receptor agonists for DC maturation in vivo, we found that IL-12p70 and interferon (IFN)-α production correlated with the maturation of CD141+ (BDCA3+) conventional DCs in huNSG mice. Furthermore, depletion of CD141+ DCs before stimulation significantly reduced IFN-α levels in vivo. This DC subset produced similar total amounts but different subtypes of IFN-α in response to synthetic double-stranded RNA compared with plasmacytoid DCs in response to a single-stranded RNA equivalent. Moreover, synthetic double-stranded RNA as adjuvant and antigen targeting to the endocytic receptor DEC-205, a combination that focuses antigen presentation for T-cell priming on CD141+ DCs, stimulated antigen-specific human CD4+ T-cell responses. Thus, the human CD141+ DC subset is a prominent source of IFN-α and interleukin-12 production and should be further evaluated for vaccine development.


Assuntos
Antígenos CD/imunologia , Células Dendríticas/imunologia , Interferon-alfa/biossíntese , Lectinas Tipo C/imunologia , Ativação Linfocitária/imunologia , RNA de Cadeia Dupla/imunologia , Receptores de Superfície Celular/imunologia , Animais , Apresentação do Antígeno/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/citologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Interferon-alfa/imunologia , Camundongos , Antígenos de Histocompatibilidade Menor
14.
Nat Chem Biol ; 9(4): 250-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23416331

RESUMO

Targeted delivery of antigens to dendritic cells (DCs) is a promising vaccination strategy. However, to ensure immunity, the approach depends on coadministration of an adjuvant. Here we ask whether targeting of both adjuvant and antigen to DCs is sufficient to induce immunity. Using a protein ligation method, we develop a general approach for linking the immune stimulant, poly dA:dT (pdA:dT), to a monoclonal antibody (mAb) specific for DEC205 (DEC). We show that DEC-specific mAbs deliver pdA:dT to DCs for the efficient production of type I interferon in human monocyte-derived DCs and in mice. Notably, adaptive T-cell immunity is elicited when mAbs specific for DEC-pdA:dT are used as the activation stimuli and are administered together with a DC-targeted antigen. Collectively, our studies indicate that DCs can integrate innate and adaptive immunity in vivo and suggest that dual delivery of antigen and adjuvant to DCs might be an efficient approach to vaccine development.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Anticorpos Monoclonais/imunologia , Antígenos CD/imunologia , Antígenos/imunologia , Células Dendríticas/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Imunoconjugados/imunologia , Lectinas Tipo C/imunologia , Poli dA-dT/imunologia , Receptores de Superfície Celular/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Antígenos/administração & dosagem , Antígenos/química , Antígenos CD/administração & dosagem , Antígenos CD/química , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos , Vetores Genéticos , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/química , Interferon Tipo I/biossíntese , Interferon Tipo I/imunologia , Lectinas Tipo C/administração & dosagem , Lectinas Tipo C/química , Camundongos , Camundongos Endogâmicos C57BL , Antígenos de Histocompatibilidade Menor , Plasmídeos , Poli dA-dT/administração & dosagem , Poli dA-dT/química , Receptores de Superfície Celular/administração & dosagem , Receptores de Superfície Celular/química
15.
PLoS One ; 7(11): e49562, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23185362

RESUMO

OBJECTIVE: To determine the function and phenotype of CD8(+) T-cells targeting consensus and autologous sequences of entire HIV-1 Nef protein. METHODS: Multiparameter flow cytometry-based analysis was used to evaluate the responses of two treatment naïve HIV-infected individuals, during primary and the chronic phases of infection. RESULTS: A greater breadth and magnitude of CD8 IFN-γ responses to autologous compared to clade-B consensus peptides was observed in both subjects. Cross recognition between autologous and consensus peptides decreased in both subjects during progression from primary to chronic infection. The frequencies of TEMRA and TEM CD8(+) T-cells targeting autologous peptides were higher than those targeting consensus peptides and were more polyfunctional (IFN-γ(+) Gr-B(+) CD107a(+)). CONCLUSIONS: Our data indicate superior sensitivity and specificity of autologous peptides. The functional and maturational aspects of "real" versus "cross-recognized" responses were also found to differ, highlighting the importance of a sequence-specific approach towards understanding HIV immune response.


Assuntos
Linfócitos T CD8-Positivos/virologia , HIV-1/metabolismo , Produtos do Gene nef do Vírus da Imunodeficiência Humana/metabolismo , Linfócitos T CD4-Positivos/citologia , Citometria de Fluxo/métodos , Granzimas/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Sistema Imunitário/virologia , Interferon gama/metabolismo , Leucócitos Mononucleares/citologia , Proteína 1 de Membrana Associada ao Lisossomo/biossíntese , Mutação , Peptídeos/química , Análise de Sequência de DNA , Staphylococcus aureus/metabolismo , Carga Viral
16.
J Exp Med ; 208(12): 2357-66, 2011 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-22065672

RESUMO

Adjuvants are critical for the success of vaccines. Agonists of microbial pattern recognition receptors (PRRs) are promising new adjuvant candidates. A mechanism through which adjuvants enhance immune responses is to stimulate innate immunity. We studied the innate immune response in humans to synthetic double-stranded RNA (polyinosinic:polycytidylic acid [poly IC] stabilized with poly-L-lysine [poly ICLC]), an agonist for toll-like receptor (TLR) 3, and the cytosolic RNA helicase MDA-5. Transcriptional analysis of blood samples from eight volunteers, after subcutaneous administration of poly ICLC, showed up-regulation of genes involved in multiple innate immune pathways in all subjects, including interferon (IFN) and inflammasome signaling. Blocking type I IFN receptor ex vivo significantly dampened the response to poly IC. Comparative transcriptional analysis showed that several innate immune pathways were similarly induced in volunteers immunized with the highly efficacious yellow fever vaccine. Therefore, a chemically defined PRR agonist like poly ICLC can be a reliable and authentic microbial mimic for inducing innate immune responses in humans.


Assuntos
Adjuvantes Imunológicos/farmacologia , Carboximetilcelulose Sódica/análogos & derivados , Regulação da Expressão Gênica/imunologia , Imunidade Inata/efeitos dos fármacos , Poli I-C/imunologia , Poli I-C/farmacologia , Polilisina/análogos & derivados , Transdução de Sinais/imunologia , Adjuvantes Imunológicos/administração & dosagem , Carboximetilcelulose Sódica/administração & dosagem , Carboximetilcelulose Sódica/farmacologia , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamassomos/metabolismo , Injeções Subcutâneas , Interferons/metabolismo , Análise em Microsséries , Poli I-C/administração & dosagem , Polilisina/administração & dosagem , Polilisina/imunologia , Polilisina/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Vacinas Virais/imunologia
17.
Nephrol Dial Transplant ; 26(9): 2852-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21292816

RESUMO

BACKGROUND: Glomerular filtration rate (GFR) decline with age increases the risk of inappropriate dosing of drugs. We investigated the determinants and the mortality associated with the use of drugs that are contraindicated or require dose adjustment according to kidney function among the community-dwelling elderly. METHODS: The Three-City population-based study included 8701 participants ≥65 years from 1999 to 2001. Exposure to the risk of inappropriate drug dosage was defined as reported use of either a contraindicated drug or one requiring dose adjustment according to the individual baseline glomerular filtration rate estimated (eGFR) with the Modification of Diet in Renal disease study equation. Six-year mortality was analysed using Cox models adjusted for several sociodemographic, biologic and clinical risk factors. RESULTS: The overall percentage of exposure to the risk of inappropriate drug use was 13.3% (contraindication, 0.8%): it was 52.5% (4.5%) in those with an eGFR of 30-59 and 96% (48%) in those <30 mL/min/1.73 m(2). Antihypertensive agents, fibrates and psycholeptics accounted for most of the drugs with dosing recommendations and antidiabetic agents and antihistamines for those contraindicated. Individuals at risk were more likely to be men, older, and under treatment for hypertension or hypercholesterolemia. Exposure to either risk was independently related to higher all-cause mortality (hazard ratio 1.4, 95% confidence interval 1.0-1.9) in participants with eGFR <60 mL/min/1.73 m(2). CONCLUSIONS: Contraindicated drug prescription was uncommon but >10% of the population took drugs requiring renal dosing adjustments. Regular monitoring of eGFR may prevent excess mortality associated with inappropriate drug prescription in the elderly.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Prescrição Inadequada/efeitos adversos , Falência Renal Crônica/mortalidade , Falência Renal Crônica/patologia , Rim/fisiopatologia , Idoso , Estudos de Coortes , Planejamento em Saúde Comunitária , Feminino , Seguimentos , França/epidemiologia , Taxa de Filtração Glomerular , Humanos , Falência Renal Crônica/epidemiologia , Testes de Função Renal , Estudos Longitudinais , Masculino , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida
18.
J Clin Immunol ; 29(5): 637-45, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19562472

RESUMO

INTRODUCTION: Due to their capacity to elicit and regulate immunity, dendritic cells (DCs) are important targets to improve vaccination. Knowing that programmed death-1 (PD-1) high virus-specific T cells become functionally exhausted during chronic exposure to human immunodeficiency virus-1 (HIV-1), the development of a therapeutic DC-based HIV-1 vaccine might include strategies that downregulate PD-L1 and PD-L2 counter-receptors. METHODS: After showing that monocyte-derived DCs rapidly upregulated PD-L1 and PD-L2 expression upon maturation with a variety of stimuli, e.g., Toll-like receptor ligands and cytokines, we determined that PD-L1 and PD-L2 expression could be knocked down by electroporation of a single small interfering RNA (siRNA) sequence twice at the monocyte and immature stages of DC development. This knockdown approached completion and was specific and lasting for several days. RESULTS: We then added the PD-L1 and PD-L2 silenced monocyte-derived DCs to peripheral blood mononuclear cells from HIV-1-infected individuals along with pools of 15-mer HIV-1 Gag p24 peptides. However, in cultures from six patients, there was only a modest enhancing effect of PD-L1 and PD-L2 silencing on CD8(+) T cell proliferative responses to the DCs. DISCUSSION: These findings suggest that, in monocyte-derived DCs, additional strategies than PD-L1 or PD-L2 blockade will be needed to improve the function of PD-1 high T cells.


Assuntos
Antígenos CD/metabolismo , Células Dendríticas/metabolismo , Infecções por HIV/imunologia , HIV-1/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Antígenos CD/genética , Antígenos CD/imunologia , Antígeno B7-H1 , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Proliferação de Células , Técnicas de Cocultura , Células Dendríticas/imunologia , Células Dendríticas/patologia , Células Dendríticas/virologia , Proteína do Núcleo p24 do HIV/química , Proteína do Núcleo p24 do HIV/imunologia , Proteína do Núcleo p24 do HIV/metabolismo , Infecções por HIV/genética , Infecções por HIV/metabolismo , Infecções por HIV/patologia , HIV-1/patogenicidade , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Ativação Linfocitária/genética , Monócitos/patologia , Monócitos/virologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Biblioteca de Peptídeos , Proteína 2 Ligante de Morte Celular Programada 1 , RNA Interferente Pequeno/genética
19.
J Am Med Inform Assoc ; 16(2): 203-10, 2009 Mar-Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19074305

RESUMO

OBJECTIVES: Medication errors constitute a major problem in all hospitals. Between 20% and 46% of prescriptions requiring dosage adjustments based on renal function are inappropriate. This study aimed to determine whether implementing alerts at the time of ordering medication integrated into the computerized physician order entry decreases the proportion of inappropriate prescriptions based on the renal function of inpatients. DESIGN: Six alternating 2-month control and intervention periods were conducted between August 2006 and August 2007 in two medical departments of a teaching hospital in France. A total of 603 patients and 38 physicians were included. During the intervention periods, alerts were triggered if a patient with renal impairment was prescribed one of the 24 targeted drugs that required adjustment according to estimated glomerular filtration rate (eGFR). MEASUREMENTS: The main outcome measure was the proportion of inappropriate first prescriptions, according to recommendation. RESULTS: A total of 1,122 alerts were triggered. The rate of inappropriate first prescriptions did not differ significantly between intervention and control periods (19.9% vs. 21.3%; p=0.63). The effect of intervention differed significantly between residents and senior physicians (p=0.03). Residents tended to make fewer errors in intervention versus control periods (Odds ratio 0.69; 95% confidence interval 0.41 to 1.15), whereas senior physicians tended to make more inappropriate prescriptions in intervention periods (odds ratio 1.88; 95% confidence interval 0.91 to 3.89). CONCLUSION: Alert activation was not followed by a significant decrease in inappropriate prescriptions in our study. Thus, it is still necessary to evaluate the impact of these systems if newly implemented in other settings thanks to studies also designed to watch for possible unanticipated effects of decision supports and their underlying causes.


Assuntos
Quimioterapia Assistida por Computador , Sistemas de Registro de Ordens Médicas , Erros de Medicação/prevenção & controle , Preparações Farmacêuticas/administração & dosagem , Sistemas de Alerta , Insuficiência Renal/tratamento farmacológico , Prescrições de Medicamentos , Feminino , França , Hospitais de Ensino/organização & administração , Humanos , Masculino , Sistemas de Medicação no Hospital , Razão de Chances , Integração de Sistemas
20.
Med Sci (Paris) ; 23(3): 279-84, 2007 Mar.
Artigo em Francês | MEDLINE | ID: mdl-17349289

RESUMO

Dendritic cells play a central role in the initiation of the immune response as they are the only antigen-presenting cells able to prime naive T cells. This makes the dendritic cells the vector of choice to use as a cell-based vaccine in immunotherapy. Although there are several strategies to deliver antigen to dendritic cells, the ones transfected with mRNA coding for tumor or viral antigens are able to induce potent antigen specific T-cell responses directed against multiple epitopes. In this review, we report several advances made in the field of anti-tumoral and anti-HIV immunotherapy using mRNA-transfected dendritic cells-based approaches.


Assuntos
Células Dendríticas/imunologia , Imunoterapia Ativa , RNA Mensageiro/genética , Animais , Apresentação do Antígeno , Antígenos CD/análise , Antígenos de Neoplasias/genética , Antígenos Virais/genética , Células Cultivadas/imunologia , Células Cultivadas/metabolismo , Ensaios Clínicos Fase I como Assunto , Células Dendríticas/classificação , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Infecções por HIV/terapia , Humanos , Ativação Linfocitária , Camundongos , Células Mieloides/citologia , Neoplasias/terapia , RNA Neoplásico/genética , RNA Viral/genética , Linfócitos T/imunologia , Transfecção
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