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1.
Haemophilia ; 22(4): e267-74, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27352908

RESUMO

INTRODUCTION: Health-related quality of life (HRQoL) of individuals with haemophilia has greatly improved with the use of factor replacement and routine prophylaxis. AIM: To explore the HRQoL of individuals with haemophilia B treated with nonacog beta pegol, an extended half-life recombinant factor IX, in a single-blind, randomized multinational phase III pivotal trial (paradigm(™) 2) and its open-label extension (paradigm(™) 4). METHODS: In the pivotal trial, adolescents and adults with haemophilia B were allocated to 28-week on-demand treatment or randomized to 52 weeks of prophylaxis with 10 or 40 IU kg(-1) nonacog beta pegol administered every seven days. In the extension trial, patients could continue on the same treatment or switch to the alternate dosing regimen at any time. HRQoL was assessed with the HAEMO-QOL/HAEM-A-QOL age-specific questionnaires and the EQ-5D. RESULTS: In the pivotal trial, adults receiving 40 IU kg(-1) prophylaxis reported significant improvements in the 'HAEM-A-QOL Total' score (-6.4 ± 8.5, P = 0.017) and in 'Sport' (-15.3 ± 8.5, P = 0.020), 'Feeling' (-15.2 ± 18.3, P = 0.010) and 'Partnership' (-9.6 ± 15.5, P = 0.046) domain scores; no significant improvements were seen in the other arms. At the pivotal trial end, fewer patients reported problems in the EQ-5D 'Mobility' and 'Pain/Discomfort' dimensions, in particular those receiving prophylaxis. In the extension trial, adult patients switching from 10 to 40 IU kg(-1) prophylaxis showed significant improvements in 'HAEM-A-QOL Total' score (-12.5 ± 8.7, P = 0.016) and 'Physical health' domain (-23.1 ± 14.4, P = 0.016). CONCLUSION: Prophylactic treatment with nonacog beta pegol 40 IU kg(-1) once weekly leads to HRQoL benefits in individuals with haemophilia B; this might be related to fewer bleeding episodes and higher FIX activity levels.


Assuntos
Coagulantes/uso terapêutico , Fator IX/uso terapêutico , Hemofilia B/tratamento farmacológico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Relação Dose-Resposta a Droga , Esquema de Medicação , Emoções , Exercício Físico , Meia-Vida , Nível de Saúde , Humanos , Masculino , Qualidade de Vida , Proteínas Recombinantes/uso terapêutico , Método Simples-Cego , Inquéritos e Questionários , Adulto Jovem
2.
Haemophilia ; 21(4): 451-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25677761

RESUMO

Haemophilia and its treatment interfere with patients' life and may affect adherence to treatment. This study explored the impact of severe haemophilia A on patients' health status, especially in young adults (YA), using data from guardian(™) 1, a multinational, open-label, non-controlled phase 3 trial investigating safety and efficacy of turoctocog alfa (NovoEight(®) ) in previously treated patients aged 12 years and older with severe haemophilia A (FVIII ≤ 1%). Health status was assessed using the EuroQoL-5 dimensions (EQ-5D-3L), covering 5 dimensions of health (mobility, self-care, usual activities, pain/discomfort and anxiety/depression), and a visual analogue scale (VAS) measuring self-rated overall health status. EQ-5D was administered pretreatment (screening/baseline) and posttreatment (end-of-trial). Baseline responses to the EQ-5D dimensions and VAS were described overall and by age and compared to reference values from UK general population. Guardian(™) 1 included 150 patients (16 adolescents, 83 YA aged 16-29 and 51 adults aged 30+). All five dimensions of patients' health status were impacted at baseline. The percentage of haemophilia patients reporting problems was consistently significantly greater than age-matched general population reference values. Likewise, for all age groups mean baseline EQ-5D VAS score was significantly lower for haemophilia patients (YA: 78.0) than for the general population (YA aged 18-29: 87.3). The health status of patients with severe haemophilia A entering guardian(™) 1 was markedly poorer than that of the general population, particularly regarding mobility and pain. YA patients reported better health status than older patients, but considerably lower than that of the general YA population.


Assuntos
Fator VIII/uso terapêutico , Nível de Saúde , Hemofilia A/tratamento farmacológico , Adolescente , Adulto , Criança , Hemofilia A/economia , Hemofilia A/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
3.
Pathol Biol (Paris) ; 63(1): 35-42, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25468489

RESUMO

The gut microbiota is increasingly considered as a symbiotic partner in the maintenance of good health. Metagenomic approaches could help to discover how the complex gut microbial ecosystem participates in the control of the host's brain development and function, and could be relevant for future therapeutic developments, such as probiotics, prebiotics and nutritional approaches for psychiatric disorders. Previous reviews focused on the effects of microbiota on the central nervous system in in vitro and animal studies. The aim of the present review is to synthetize the current data on the association between microbiota dysbiosis and onset and/or maintenance of major psychiatric disorders, and to explore potential therapeutic opportunities targeting microbiota dysbiosis in psychiatric patients.


Assuntos
Disbiose/dietoterapia , Transtornos Mentais/dietoterapia , Microbiota/efeitos dos fármacos , Prebióticos , Probióticos/uso terapêutico , Animais , Suplementos Nutricionais , Sistemas de Liberação de Medicamentos/métodos , Disbiose/complicações , Disbiose/microbiologia , Humanos , Transtornos Mentais/complicações , Transtornos Mentais/microbiologia , Prebióticos/administração & dosagem
4.
Haemophilia ; 20(4): 527-34, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24471912

RESUMO

Haemophilia and its treatment interfere with patients' life, so health-related quality of life (HRQoL) should be assessed when evaluating treatments. This study investigated the HRQoL of patients with haemophilia A treated prophylactically with a new recombinant factor VIII. Two phase 3 trials investigated turoctocog alfa in patients with severe haemophilia A: one in children, one in adults and adolescents. HRQoL was a secondary endpoint assessed by the HAEMO-QOL age-specific, self-administered questionnaires. Parent-completed versions were also included for parents of children and adolescents. All HAEMO-QOL questionnaires allow the calculation of domain-specific and total scores ranging from 0 to 100, lower scores indicating better HRQoL. Mean change in all scores was described for 25 children aged 4-7 years, 21 children aged 8-12 years, 18 adolescents aged 13-18 years and 129 adults, overall, and according to the treatment regimen received prior to the study (on-demand; prophylaxis; mixed). Mean changes in HAEMO-QOL total score were 1.4 for children aged 4-7 years, -2.6 for children aged 8-12 years, -5.8 for adolescents and -1.6 for adults. In parent-completed versions, mean changes in total score were -6.0 for children aged 4-7 years, -4.7 for children aged 8-12 years, and -10.0 for adolescents. Patients receiving on-demand treatment before the trial showed greater improvement in HRQoL scores than patients already on prophylaxis. HRQoL of patients remained fairly stable over the course of the trials. However, improvements were observed for adolescents. Switching to prophylaxis was identified as a potential driver of improvement of HRQoL in patients with haemophilia A.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Qualidade de Vida , Adolescente , Adulto , Criança , Pré-Escolar , Fator VIII/farmacologia , Saúde , Hemofilia A/prevenção & controle , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
7.
Osteoporos Int ; 23(2): 445-55, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21625889

RESUMO

SUMMARY: We developed and validated a specific 12-item questionnaire to evaluate adherence to oral antiresorptive medication by post-menopausal osteoporotic women in everyday practice. Over the following 9 months, an index of ≤16 was associated with an increase in the risk of treatment discontinuation of 1.69 and of 2.10 for new patients who had started treatment within the previous year. INTRODUCTION: Adherence to medication in osteoporosis is poor. The goal of this study was to develop and validate a disease-specific questionnaire to evaluate adherence to treatment of women with post-menopausal osteoporosis taking oral antiresorptive medication. METHODS: A prototype adherence questionnaire with 45 items developed from patient interview, literature review, and physician opinion was evaluated in a sample of 350 post-menopausal women with osteoporosis treated in primary care. Item responses were matched against scores on the Morisky Medication Adherence Scale (MMAS). The most discriminant items were retained in the final questionnaire. Concurrent and predictive validity were assessed. RESULTS: Twelve items were associated with MMAS score at a probability level of 0.05. These were retained in the final questionnaire which provided an adherence index ranging from 0 to 22. An index of ≥20 was associated with a high probability of persistence and an index ≤ 16 with a high probability of treatment discontinuation in the following 9 months. CONCLUSIONS: The ADEOS-12 is a simple patient-reported measure to determine adherence to osteoporosis treatments with good concurrent and discriminant validity. This is the first disease-specific adherence measure to have been developed for osteoporosis.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Adesão à Medicação , Osteoporose Pós-Menopausa/tratamento farmacológico , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Conservadores da Densidade Óssea/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/psicologia , Psicometria
8.
Artigo em Inglês | MEDLINE | ID: mdl-21760726

RESUMO

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is a worldwide public health concern. It is also a major source of disability that is often overlooked, depriving patients of effective treatments. This study describes the development and validation of a questionnaire specifically assessing COPD-related disability. METHODS: The DIsability RElated to COPD Tool (DIRECT) was developed according to reference methods, including literature review, patient and clinician interviews and test in a pilot study. A 12-item questionnaire was included for finalization and validation in an observational cross-sectional study conducted by 60 French pulmonologists, who recruited 275 COPD patients of stage II, III and IV according to the GOLD classification. Rasch modeling was conducted and psychometric properties were assessed (internal consistency reliability; concurrent and clinical validity). RESULTS: The DIRECT score was built from the 10 items retained in the Rasch model. Their internal consistency reliability was excellent (Cronbach's alpha = 0.95). The score was highly correlated with the Saint George's Respiratory Questionnaire Activity score (r = 0.83) and the London Handicap Scale (r = -0.70), a generic disability measure. It was highly statistically significantly associated to four clinical parameters (P < 0.001): GOLD classification, BODE index, FEV1 and 6-minute walk distance. CONCLUSION: DIRECT is a promising tool that could help enhance the management of COPD patients by integrating an evaluation of the COPD-related disability into daily practice.


Assuntos
Avaliação da Deficiência , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Inquéritos e Questionários , Atividades Cotidianas , Idoso , Distribuição de Qui-Quadrado , Efeitos Psicossociais da Doença , Estudos Transversais , Teste de Esforço , Tolerância ao Exercício , Feminino , Volume Expiratório Forçado , França , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Psicometria , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Espirometria , Caminhada
9.
Dev Biol (Basel) ; 131: 157-66, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18634476

RESUMO

In India, about 20,000 people die of rabies every year. The dog is the main reservoir and transmitter of the disease. A pilot rabies control programme was launched in five Indian federal states in February, 2007. This initiative is led by the Animal Welfare Board of India (AWBI) federating many animal welfare organizations and the Ministry of Agriculture. It aims at creating a "Rabies Free India." The programme combines parenteral vaccination of accessible owned and stray dogs, spaying/neutering followed by parenteral vaccination and oral vaccination of inaccessible dogs. The freeze-dried vaccine SAG2, including the bait casing, was registered in India following successful evaluation of vaccine-bait safety and efficacy (by survival after virulent challenge) in captive Indian stray dogs in the Bhopal High Security Animal Disease Laboratory. Furthermore, bait acceptance was tested under both experimental and field conditions.


Assuntos
Doenças do Cão/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/imunologia , Raiva/veterinária , Vacinação/veterinária , Administração Oral , Animais , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Cães , Feminino , Humanos , Índia/epidemiologia , Infusões Parenterais/veterinária , Masculino , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/transmissão , Segurança , Saliva/virologia , Resultado do Tratamento , Vacinação/efeitos adversos , Vacinação/métodos
10.
Vaccine ; 25(17): 3409-18, 2007 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-17224221

RESUMO

India is one of the countries with the highest prevalence of human rabies throughout the world. Dogs are primarily responsible for rabies transmission. Among them, stray dogs play a major role in that country. Parenteral vaccination programmes are insufficient to eliminate rabies partly due to difficulties in establishing satisfactory immunisation coverage in the dog population in view of the high proportion of stray dogs. Oral vaccination may be a useful adjunct to parenteral vaccination by increasing dog vaccination coverage. Safety, immunogenicity and efficacy of Rabidog SAG2 bait were evaluated in Indian stray dogs in captivity. Safety of SAG2 was demonstrated by the absence of adverse clinical sign, salivary excretion and absence of replication of the vaccine strain in brain and salivary glands of 21 vaccinated dogs, even when immunodepressed. Efficacy was shown 109 days post-vaccination after challenge with a highly virulent street rabies virus which killed all five controls whereas all nine vaccinated dogs survived, despite the fact that only five out of nine had seroconverted before challenge.


Assuntos
Vacina Antirrábica/imunologia , Administração Oral , Animais , Anticorpos Antivirais/sangue , Cães , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/efeitos adversos , Segurança , Saliva/virologia , Vacinação , Vacinas Atenuadas/imunologia
11.
Nat Med ; 7(3): 297-303, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231627

RESUMO

The initiation of T-cell-mediated antitumor immune responses requires the uptake and processing of tumor antigens by dendritic cells and their presentation on MHC-I molecules. Here we show in a human in vitro model system that exosomes, a population of small membrane vesicles secreted by living tumor cells, contain and transfer tumor antigens to dendritic cells. After mouse tumor exosome uptake, dendritic cells induce potent CD8+ T-cell-dependent antitumor effects on syngeneic and allogeneic established mouse tumors. Therefore, exosomes represent a novel source of tumor-rejection antigens for T-cell cross priming, relevant for immunointerventions.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias Mamárias Experimentais/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Células Dendríticas/imunologia , Humanos , Neoplasias Mamárias Experimentais/ultraestrutura , Camundongos , Microscopia Imunoeletrônica , Células Tumorais Cultivadas
12.
Nutr Neurosci ; 4(5): 413-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11842917

RESUMO

Brain serotonin synthesis depends on the uptake of its precursor, tryptophan (Trp), and is correlated to the plasma ratio of Trp to large neutral amino acids (LNAA) which compete for the same transporter system in the brain. As the plasma Trp/LNAA ratio decreases when the dietary protein content exceeds 5%, we tested whether a diet containing 17% of a Trp-rich protein, namely alpha-lactalbumin (LAC), might increase the plasma Trp/LNAA ratio over a long period. Blood samples were obtained at different days (-1, 3, 6 and 9) from rats receiving either a LAC or casein (CAS) diet, and plasma amino acids and insulin concentrations were determined. The increase in plasma Trp concentration was much higher during the LAC diet (49 vs 26%; P<0.001), while the plasma LNAA concentration remained fairly constant. Consequently, the plasma Trp/LNAA ratio increased by 40% during the LAC diet while it decreased by 15% during the CAS diet (P<0.001). The above results were not related to plasma insulin concentration differences during these diets. These data suggest that a balanced diet containing a natural Trp rich-protein increases the plasma Trp/LNAA ratio over a long period, leading to a probable increase in brain serotonin activity.


Assuntos
Aminoácidos Neutros/sangue , Dieta , Lactalbumina/administração & dosagem , Triptofano/sangue , Aminoácidos/sangue , Animais , Encéfalo/metabolismo , Caseínas/administração & dosagem , Insulina/sangue , Masculino , Ratos , Ratos Wistar , Serotonina/metabolismo
13.
J Immunol ; 165(6): 3301-8, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10975847

RESUMO

Immunization with peptide or recombinant proteins generally fails to elicit CTL, which are thought to play a key role in the control of virus-infected cells and tumor growth. In this study we show that the nontoxic B subunit of Shiga toxin fused to a tumor peptide derived from the mouse mastocytoma P815 can induce specific CTL in mice without the use of adjuvant. The Shiga B subunit acts as a vector rather than as an adjuvant, because coinjection of the tumor peptide and the B subunit as separate entities does not lead to CTL induction. We also demonstrated that in vitro the B subunit mediates the delivery of various exogenous CD8 T cell epitopes into the conventional MHC class I-restricted pathway, as this process is inhibited by brefeldin A and lactacystin and requires a functional TAP system. In contrast to other nonviral methods for transport of exogenous Ags into the endogenous MHC class I pathway that involve macropinocytosis or phagocytosis, the Shiga B subunit targets this pathway in a receptor-dependent manner, namely via binding to the glycolipid Gb3. Because this receptor is highly expressed on various dendritic cells, it should allow preferential targeting of the Shiga B subunit to these professional APCs. Therefore, the Shiga B subunit appears to represent an attractive vector for vaccine development due to its ability to target dendritic cells and to induce specific CTL without the need for adjuvant.


Assuntos
Acetilcisteína/análogos & derivados , Apresentação de Antígeno/genética , Antígenos de Neoplasias/genética , Toxinas Bacterianas/imunologia , Células Dendríticas/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Peptídeos/imunologia , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T Citotóxicos/imunologia , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/fisiologia , Acetilcisteína/farmacologia , Animais , Apresentação de Antígeno/efeitos dos fármacos , Antígenos de Neoplasias/administração & dosagem , Antígenos de Neoplasias/imunologia , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Brefeldina A/farmacologia , Citotoxicidade Imunológica/genética , Células Dendríticas/metabolismo , Feminino , Injeções Intraperitoneais , Líquido Intracelular/imunologia , Líquido Intracelular/metabolismo , Leucemia L1210 , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Ovalbumina/metabolismo , Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Sarcoma Experimental/genética , Sarcoma Experimental/imunologia , Toxinas Shiga , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/metabolismo , Células Tumorais Cultivadas
14.
J Cell Biol ; 147(3): 599-610, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10545503

RESUMO

Exosomes are membrane vesicles secreted by hematopoietic cells upon fusion of late multivesicular endosomes with the plasma membrane. Dendritic cell (DC)-derived exosomes induce potent antitumor immune responses in mice, resulting in the regression of established tumors (Zitvogel, L., A. Regnault, A. Lozier, J. Wolfers, C. Flament, D. Tenza, P. Ricciardi-Castagnoli, G. Raposo, and S. Amigorena. 1998. Nat. Med. 4:594-600). To unravel the molecular basis of exosome-induced immune stimulation, we now analyze the regulation of their production during DC maturation and characterize extensively their protein composition by peptide mass mapping. Exosomes contain several cytosolic proteins (including annexin II, heat shock cognate protein hsc73, and heteromeric G protein Gi2alpha), as well as different integral or peripherally associated membrane proteins (major histocompatibility complex class II, Mac-1 integrin, CD9, milk fat globule-EGF-factor VIII [MFG-E8]). MFG-E8, the major exosomal component, binds integrins expressed by DCs and macrophages, suggesting that it may be involved in exosome targeting to these professional antigen-presenting cells. Another exosome component is hsc73, a cytosolic heat shock protein (hsp) also present in DC endocytic compartments. hsc73 was shown to induce antitumor immune responses in vivo, and therefore could be involved in the exosome's potent antitumor effects. Finally, exosome production is downregulated upon DC maturation, indicating that in vivo, exosomes are produced by immature DCs in peripheral tissues. Thus, DC-derived exosomes accumulate a defined subset of cellular proteins reflecting their endosomal biogenesis and accounting for their biological function.


Assuntos
Antígenos de Superfície , Células Dendríticas/metabolismo , Exocitose , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico/metabolismo , Proteínas do Leite , Organelas/química , Organelas/metabolismo , Animais , Anexina A2/metabolismo , Antineoplásicos/imunologia , Antineoplásicos/metabolismo , Diferenciação Celular , Linhagem Celular , Citosol/metabolismo , Células Dendríticas/química , Células Dendríticas/ultraestrutura , Endossomos/química , Endossomos/metabolismo , Proteínas de Choque Térmico HSC70 , Proteínas de Choque Térmico/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Integrinas/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peso Molecular , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Organelas/ultraestrutura , Mapeamento de Peptídeos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Nat Cell Biol ; 1(6): 362-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10559964

RESUMO

In order for cytotoxic T cells to initiate immune responses, peptides derived from internalized antigens must be presented to the cytotoxic T cells on major histocompatibility complex (MHC) class I molecules. Here we show that dendritic cells, the only antigen-presenting cells that initiate immune responses efficiently, have developed a unique membrane transport pathway linking the lumen of endocytic compartments and the cytosol. Endosome-to-cytosol transport is restricted to dendritic cells, specific to internalized antigens and selective for the size of the transported molecules. Thus, in dendritic cells, internalized antigens gain access to the cytosolic antigen-processing machinery and to the conventional MHC class I antigen-presentation pathway.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos/metabolismo , Células Dendríticas/imunologia , Endocitose/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Animais , Antígenos/imunologia , Transporte Biológico , Células Cultivadas , Citosol/imunologia , Células Dendríticas/citologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina/imunologia
16.
J Immunol ; 162(8): 4567-75, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10201996

RESUMO

TGF-beta 1 is critical for differentiation of epithelial-associated dendritic Langerhans cells (LC). In accordance with the characteristics of in vivo LC, we show that LC obtained from human monocytes in vitro in the presence of TGF-beta 1 1) express almost exclusively intracellular class II Ags, low CD80, and no CD83 and CD86 Ags and 2) down-regulate TNF-RI (p55) and do not produce IL-10 after stimulation, in contrast to dermal dendritic cells and monocyte-derived dendritic cells. Surprisingly, while LC exhibit E-cadherin down-regulation upon exposure to TNF-alpha and IL-1, TGF-beta 1 prevents the final LC maturation in response to TNF-alpha, IL-1, and LPS with respect to Class II CD80, CD86, and CD83 Ag expression, loss of FITC-dextran uptake, production of IL-12, and Ag presentation. In sharp contrast, CD40 ligand cognate signal induces full maturation of LC and is not inhibited by TGF-beta 1. The presence of emigrated immature LCs in human reactive skin-draining lymph nodes provides in vivo evidence that LC migration and final maturation may be differentially regulated. Therefore, due to the effects of TGF-beta 1, inflammatory stimuli may not be sufficient to induce full maturation of LC, thus avoiding potentially harmful immune responses. We conclude that TGF-beta 1 appears to be responsible for both the acquisition of LC phenotype, cytokine production pattern, and prevention of noncognate maturation.


Assuntos
Inibidores do Crescimento/fisiologia , Células de Langerhans/citologia , Células de Langerhans/imunologia , Fator de Crescimento Transformador beta/fisiologia , Antígenos CD/biossíntese , Antígenos CD/química , Antígenos CD40/metabolismo , Ligante de CD40 , Diferenciação Celular/imunologia , Movimento Celular/imunologia , Células Cultivadas , Regulação para Baixo/imunologia , Humanos , Imunofenotipagem , Interleucina-1/antagonistas & inibidores , Interleucina-1/farmacologia , Interleucina-10/antagonistas & inibidores , Interleucina-10/biossíntese , Interleucina-12/antagonistas & inibidores , Interleucina-12/biossíntese , Células de Langerhans/metabolismo , Ligantes , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/fisiologia , Monócitos/citologia , Monócitos/imunologia , Pinocitose/imunologia , Receptores do Fator de Necrose Tumoral/biossíntese , Receptores do Fator de Necrose Tumoral/química , Receptores Tipo I de Fatores de Necrose Tumoral , Linfócitos T/imunologia , Toxina Tetânica/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/farmacologia
17.
J Exp Med ; 189(2): 371-80, 1999 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-9892619

RESUMO

Dendritic cells (DCs) express several receptors for the Fc portion of immunoglobulin (Ig)G (FcgammaR), which mediate internalization of antigen-IgG complexes (immune complexes, ICs) and promote efficient major histocompatibility complex (MHC) class II-restricted antigen presentation. We now show that FcgammaRs have two additional specific attributes in murine DCs: the induction of DC maturation and the promotion of efficient MHC class I-restricted presentation of peptides from exogenous, IgG-complexed antigens. Both FcgammaR functions require the FcgammaR-associated gamma chain. FcgammaR-mediated MHC class I-restricted antigen presentation is extremely sensitive and specific to immature DCs. It requires proteasomal degradation and is dependent on functional peptide transporter associated with antigen processing, TAP1-TAP2. By promoting DC maturation and presentation on both MHC class I and II molecules, ICs should efficiently sensitize DCs for priming of both CD4(+) helper and CD8(+) cytotoxic T lymphocytes in vivo.


Assuntos
Apresentação de Antígeno/imunologia , Complexo Antígeno-Anticorpo/imunologia , Células Dendríticas/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Receptores de IgG/imunologia , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/imunologia , Animais , Antígenos CD/imunologia , Medula Óssea/imunologia , Cisteína Endopeptidases/metabolismo , Imunofluorescência , Imunoglobulina G/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Knockout , Complexos Multienzimáticos/metabolismo , Ovalbumina/imunologia , Complexo de Endopeptidases do Proteassoma
19.
J Immunol ; 161(5): 2106-13, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9725201

RESUMO

Inside APCs, MHC class II molecules associate with antigenic peptides before reaching the cell surface. This association takes place in compartments of the endocytic pathway, more related to endosomes or lysosomes depending on the cell type. Here, we compared MHC class II transport from endosomal vs lysosomal compartments to the plasma membrane. We show that transport of MHC class II molecules to the cell surface does not depend on the cytosolic domains of the alpha- and beta-chains. In contrast, the stability of the alphabeta-peptide complexes determined the efficiency of transport to the cell surface from lysosomal, but not from endosomal, compartments. In murine B lymphoma cells, SDS-unstable and -stable complexes were transported to the cell surface at almost similar rates, whereas after lysosomal relocalization or in a cell line in which MHC class II molecules normally accumulate in lysosomal compartments, stable complexes were preferentially addressed to the cell surface. Our results suggest that when peptide loading occurs in lysosomal compartments, selective retention and lysosomal degradation of unstable dimers result in the expression of highly stable MHC class II-peptide complexes at the APC surface.


Assuntos
Citosol/metabolismo , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/metabolismo , Lisossomos/imunologia , Fragmentos de Peptídeos/metabolismo , Estrutura Terciária de Proteína , Sequência de Aminoácidos , Animais , Transporte Biológico/genética , Transporte Biológico/imunologia , Compartimento Celular/genética , Compartimento Celular/imunologia , Membrana Celular/imunologia , Membrana Celular/metabolismo , Citosol/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Eletroforese em Gel de Poliacrilamida , Endossomos/imunologia , Endossomos/metabolismo , Antígenos de Histocompatibilidade Classe II/genética , Linfoma de Células B/genética , Linfoma de Células B/imunologia , Linfoma de Células B/metabolismo , Lisossomos/metabolismo , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Ligação Proteica/genética , Ligação Proteica/imunologia , Dodecilsulfato de Sódio , Células Tumorais Cultivadas
20.
Nat Med ; 4(5): 594-600, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9585234

RESUMO

Dendritic cells (DCs) are professional antigen presenting cells with the unique capacity to induce primary and secondary immune responses in vivo. Here, we show that DCs secrete antigen presenting vesicles, called exosomes, which express functional Major Histocompatibility Complex class I and class II, and T-cell costimulatory molecules. Tumor peptide-pulsed DC-derived exosomes prime specific cytotoxic T lymphocytes in vivo and eradicate or suppress growth of established murine tumors in a T cell-dependent manner. Exosome-based cell-free vaccines represent an alternative to DC adoptive therapy for suppressing tumor growth.


Assuntos
Vacinas Anticâncer/uso terapêutico , Células Dendríticas/imunologia , Neoplasias Experimentais/terapia , Frações Subcelulares/imunologia , Adenocarcinoma/imunologia , Animais , Apresentação de Antígeno , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Sistema Livre de Células , Feminino , Antígenos H-2/genética , Antígenos de Histocompatibilidade Classe I , Antígenos de Histocompatibilidade Classe II , Ativação Linfocitária , Neoplasias Mamárias Animais/imunologia , Sarcoma de Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos Nus , Neoplasias Experimentais/imunologia , Fragmentos de Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia
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