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1.
Haemophilia ; 22(4): e267-74, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27352908

ABSTRACT

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.


Subject(s)
Coagulants/therapeutic use , Factor IX/therapeutic use , Hemophilia B/drug therapy , Polyethylene Glycols/therapeutic use , Adolescent , Adult , Dose-Response Relationship, Drug , Drug Administration Schedule , Emotions , Exercise , Half-Life , Health Status , Humans , Male , Quality of Life , Recombinant Proteins/therapeutic use , Single-Blind Method , Surveys and Questionnaires , Young Adult
2.
Haemophilia ; 21(4): 451-7, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25677761

ABSTRACT

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.


Subject(s)
Factor VIII/therapeutic use , Health Status , Hemophilia A/drug therapy , Adolescent , Adult , Child , Hemophilia A/economics , Hemophilia A/pathology , Humans , Male , Middle Aged , Quality of Life , Severity of Illness Index , Treatment Outcome , Young Adult
3.
Pathol Biol (Paris) ; 63(1): 35-42, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25468489

ABSTRACT

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.


Subject(s)
Dysbiosis/diet therapy , Mental Disorders/diet therapy , Microbiota/drug effects , Prebiotics , Probiotics/therapeutic use , Animals , Dietary Supplements , Drug Delivery Systems/methods , Dysbiosis/complications , Dysbiosis/microbiology , Humans , Mental Disorders/complications , Mental Disorders/microbiology , Prebiotics/administration & dosage
4.
Haemophilia ; 20(4): 527-34, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24471912

ABSTRACT

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.


Subject(s)
Factor VIII/therapeutic use , Hemophilia A/drug therapy , Quality of Life , Adolescent , Adult , Child , Child, Preschool , Factor VIII/pharmacology , Health , Hemophilia A/prevention & control , Humans , Middle Aged , Surveys and Questionnaires , Young Adult
7.
Osteoporos Int ; 23(2): 445-55, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21625889

ABSTRACT

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.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Medication Adherence , Osteoporosis, Postmenopausal/drug therapy , Surveys and Questionnaires , Aged , Aged, 80 and over , Attitude to Health , Bone Density Conservation Agents/administration & dosage , Drug Administration Schedule , Female , Humans , Middle Aged , Osteoporosis, Postmenopausal/psychology , Psychometrics
8.
Article in English | MEDLINE | ID: mdl-21760726

ABSTRACT

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.


Subject(s)
Disability Evaluation , Pulmonary Disease, Chronic Obstructive/diagnosis , Surveys and Questionnaires , Activities of Daily Living , Aged , Chi-Square Distribution , Cost of Illness , Cross-Sectional Studies , Exercise Test , Exercise Tolerance , Female , Forced Expiratory Volume , France , Humans , Lung/physiopathology , Male , Middle Aged , Predictive Value of Tests , Psychometrics , Pulmonary Disease, Chronic Obstructive/physiopathology , Reproducibility of Results , Severity of Illness Index , Spirometry , Walking
9.
Dev Biol (Basel) ; 131: 157-66, 2008.
Article in English | MEDLINE | ID: mdl-18634476

ABSTRACT

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.


Subject(s)
Dog Diseases/prevention & control , Rabies Vaccines/administration & dosage , Rabies Vaccines/immunology , Rabies/veterinary , Vaccination/veterinary , Administration, Oral , Animals , Dog Diseases/epidemiology , Dog Diseases/transmission , Dogs , Female , Humans , India/epidemiology , Infusions, Parenteral/veterinary , Male , Rabies/epidemiology , Rabies/prevention & control , Rabies/transmission , Safety , Saliva/virology , Treatment Outcome , Vaccination/adverse effects , Vaccination/methods
10.
Vaccine ; 25(17): 3409-18, 2007 Apr 30.
Article in English | MEDLINE | ID: mdl-17224221

ABSTRACT

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.


Subject(s)
Rabies Vaccines/immunology , Administration, Oral , Animals , Antibodies, Viral/blood , Dogs , Rabies Vaccines/administration & dosage , Rabies Vaccines/adverse effects , Safety , Saliva/virology , Vaccination , Vaccines, Attenuated/immunology
11.
Nat Med ; 7(3): 297-303, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11231627

ABSTRACT

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.


Subject(s)
Antigens, Neoplasm/immunology , Mammary Neoplasms, Experimental/immunology , T-Lymphocytes, Cytotoxic/immunology , Animals , Dendritic Cells/immunology , Humans , Mammary Neoplasms, Experimental/ultrastructure , Mice , Microscopy, Immunoelectron , Tumor Cells, Cultured
12.
Nutr Neurosci ; 4(5): 413-8, 2001.
Article in English | MEDLINE | ID: mdl-11842917

ABSTRACT

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.


Subject(s)
Amino Acids, Neutral/blood , Diet , Lactalbumin/administration & dosage , Tryptophan/blood , Amino Acids/blood , Animals , Brain/metabolism , Caseins/administration & dosage , Insulin/blood , Male , Rats , Rats, Wistar , Serotonin/metabolism
13.
J Immunol ; 165(6): 3301-8, 2000 Sep 15.
Article in English | MEDLINE | ID: mdl-10975847

ABSTRACT

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.


Subject(s)
Acetylcysteine/analogs & derivatives , Antigen Presentation/genetics , Antigens, Neoplasm/genetics , Bacterial Toxins/immunology , Dendritic Cells/immunology , Histocompatibility Antigens Class I/immunology , Peptides/immunology , Recombinant Fusion Proteins/immunology , T-Lymphocytes, Cytotoxic/immunology , ATP Binding Cassette Transporter, Subfamily B, Member 2 , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/physiology , Acetylcysteine/pharmacology , Animals , Antigen Presentation/drug effects , Antigens, Neoplasm/administration & dosage , Antigens, Neoplasm/immunology , Bacterial Toxins/administration & dosage , Bacterial Toxins/genetics , Bacterial Toxins/metabolism , Brefeldin A/pharmacology , Cytotoxicity, Immunologic/genetics , Dendritic Cells/metabolism , Female , Injections, Intraperitoneal , Intracellular Fluid/immunology , Intracellular Fluid/metabolism , Leukemia L1210 , Lymphocyte Activation/genetics , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Mice, Knockout , Ovalbumin/administration & dosage , Ovalbumin/immunology , Ovalbumin/metabolism , Peptides/metabolism , Protein Processing, Post-Translational/drug effects , Protein Processing, Post-Translational/immunology , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/genetics , Sarcoma, Experimental/genetics , Sarcoma, Experimental/immunology , Shiga Toxins , Signal Transduction/genetics , Signal Transduction/immunology , T-Lymphocytes, Cytotoxic/metabolism , Tumor Cells, Cultured
14.
J Cell Biol ; 147(3): 599-610, 1999 Nov 01.
Article in English | MEDLINE | ID: mdl-10545503

ABSTRACT

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.


Subject(s)
Antigens, Surface , Dendritic Cells/metabolism , Exocytosis , HSP70 Heat-Shock Proteins , Heat-Shock Proteins/metabolism , Milk Proteins , Organelles/chemistry , Organelles/metabolism , Animals , Annexin A2/metabolism , Antineoplastic Agents/immunology , Antineoplastic Agents/metabolism , Cell Differentiation , Cell Line , Cytosol/metabolism , Dendritic Cells/chemistry , Dendritic Cells/ultrastructure , Endosomes/chemistry , Endosomes/metabolism , HSC70 Heat-Shock Proteins , Heat-Shock Proteins/immunology , Histocompatibility Antigens Class II/metabolism , Integrins/metabolism , Macrophages/cytology , Macrophages/immunology , Membrane Glycoproteins/metabolism , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Molecular Weight , Neoplasms, Experimental/immunology , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Organelles/ultrastructure , Peptide Mapping , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
15.
Nat Cell Biol ; 1(6): 362-8, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10559964

ABSTRACT

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.


Subject(s)
Antigen Presentation/immunology , Antigens/metabolism , Dendritic Cells/immunology , Endocytosis/immunology , Histocompatibility Antigens Class I/immunology , Animals , Antigens/immunology , Biological Transport , Cells, Cultured , Cytosol/immunology , Dendritic Cells/cytology , Macrophages/immunology , Mice , Mice, Inbred C57BL , Ovalbumin/immunology
16.
J Immunol ; 162(8): 4567-75, 1999 Apr 15.
Article in English | MEDLINE | ID: mdl-10201996

ABSTRACT

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.


Subject(s)
Growth Inhibitors/physiology , Langerhans Cells/cytology , Langerhans Cells/immunology , Transforming Growth Factor beta/physiology , Antigens, CD/biosynthesis , Antigens, CD/chemistry , CD40 Antigens/metabolism , CD40 Ligand , Cell Differentiation/immunology , Cell Movement/immunology , Cells, Cultured , Down-Regulation/immunology , Humans , Immunophenotyping , Interleukin-1/antagonists & inhibitors , Interleukin-1/pharmacology , Interleukin-10/antagonists & inhibitors , Interleukin-10/biosynthesis , Interleukin-12/antagonists & inhibitors , Interleukin-12/biosynthesis , Langerhans Cells/metabolism , Ligands , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Lymphocyte Activation/immunology , Membrane Glycoproteins/physiology , Monocytes/cytology , Monocytes/immunology , Pinocytosis/immunology , Receptors, Tumor Necrosis Factor/biosynthesis , Receptors, Tumor Necrosis Factor/chemistry , Receptors, Tumor Necrosis Factor, Type I , T-Lymphocytes/immunology , Tetanus Toxin/pharmacology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/pharmacology
17.
J Exp Med ; 189(2): 371-80, 1999 Jan 18.
Article in English | MEDLINE | ID: mdl-9892619

ABSTRACT

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.


Subject(s)
Antigen Presentation/immunology , Antigen-Antibody Complex/immunology , Dendritic Cells/immunology , Histocompatibility Antigens Class I/immunology , Receptors, IgG/immunology , ATP Binding Cassette Transporter, Subfamily B, Member 2 , ATP Binding Cassette Transporter, Subfamily B, Member 3 , ATP-Binding Cassette Transporters/immunology , Animals , Antigens, CD/immunology , Bone Marrow/immunology , Cysteine Endopeptidases/metabolism , Fluorescent Antibody Technique , Immunoglobulin G/immunology , Lipopolysaccharides/pharmacology , Mice , Mice, Knockout , Multienzyme Complexes/metabolism , Ovalbumin/immunology , Proteasome Endopeptidase Complex
19.
J Immunol ; 161(5): 2106-13, 1998 Sep 01.
Article in English | MEDLINE | ID: mdl-9725201

ABSTRACT

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.


Subject(s)
Cytosol/metabolism , Histocompatibility Antigens Class II/chemistry , Histocompatibility Antigens Class II/metabolism , Lysosomes/immunology , Peptide Fragments/metabolism , Protein Structure, Tertiary , Amino Acid Sequence , Animals , Biological Transport/genetics , Biological Transport/immunology , Cell Compartmentation/genetics , Cell Compartmentation/immunology , Cell Membrane/immunology , Cell Membrane/metabolism , Cytosol/immunology , Dendritic Cells/immunology , Dendritic Cells/metabolism , Electrophoresis, Polyacrylamide Gel , Endosomes/immunology , Endosomes/metabolism , Histocompatibility Antigens Class II/genetics , Lymphoma, B-Cell/genetics , Lymphoma, B-Cell/immunology , Lymphoma, B-Cell/metabolism , Lysosomes/metabolism , Mice , Molecular Sequence Data , Peptide Fragments/genetics , Peptide Fragments/immunology , Protein Binding/genetics , Protein Binding/immunology , Sodium Dodecyl Sulfate , Tumor Cells, Cultured
20.
Nat Med ; 4(5): 594-600, 1998 May.
Article in English | MEDLINE | ID: mdl-9585234

ABSTRACT

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.


Subject(s)
Cancer Vaccines/therapeutic use , Dendritic Cells/immunology , Neoplasms, Experimental/therapy , Subcellular Fractions/immunology , Adenocarcinoma/immunology , Animals , Antigen Presentation , Antigens, Neoplasm/immunology , Cancer Vaccines/immunology , Cell-Free System , Female , H-2 Antigens/genetics , Histocompatibility Antigens Class I , Histocompatibility Antigens Class II , Lymphocyte Activation , Mammary Neoplasms, Animal/immunology , Mast-Cell Sarcoma/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred DBA , Mice, Nude , Neoplasms, Experimental/immunology , Peptide Fragments/immunology , T-Lymphocytes, Cytotoxic/immunology
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