RESUMO
OBJECTIVES: The potential of sports clubs to promote health beyond physical activity has been acknowledged by researchers and policy-makers. This study gathered stakeholder ideas on support sports clubs need to increase health promotion efforts and prioritize them based on importance and feasibility. STUDY DESIGN: The study design used in this study is a mixed-methods concept mapping approach. METHODS: French sports and public health stakeholders (n = 45) were invited to participate. Steps included are as follows: (1) formulating a focus prompt, (2) brainstorming statements in response to the focus prompt, (3) sorting statements into themed piles, and (4) rating statements based on indicators. Multidimensional scaling and hierarchical cluster analysis were used to produce visual cluster maps, and descriptive statistics generated Go-Zone graphs based on mean importance and feasible ratings. RESULTS: Participants generated 62 statements from the focus prompt: 'What assistance would benefit sports clubs to become a health-promoting setting?'. Final sorting produced 9 clusters: Tools for health promotion, Communication tools, Stakeholder training courses, Diagnostic and Financing, Awareness and Mobilization, Advocacy, Policies and Methods, Sharing and Networking, as well as Communication and Dissemination. Participant ratings produced 34 statements within the Go-Zone graphs. CONCLUSION: Understanding stakeholders' needs to increase health promotion activities in sports clubs is crucial to planning and implementing sustainable health promotion policies and practice. Priority areas include increasing awareness of health promotion benefits, mobilizing actors, advocating for support, and educating sports club actors.
Assuntos
Academias de Ginástica/organização & administração , Promoção da Saúde/métodos , Promoção da Saúde/organização & administração , Esportes , Adolescente , Adulto , Análise por Conglomerados , Feminino , França , Política de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Saúde Pública , Adulto JovemRESUMO
The discovery of tumor-associated antigens recognized by T lymphocytes opens the possibility of vaccinating cancer patients with defined antigens. However, one of the major limitation of peptide-based vaccines is the low immunogenicity of antigenic peptides. Interestingly, if these epitopes are directly delivered into the cytoplasm of antigen presenting cells, they can be efficiently presented via the direct MHC class I presentation pathway. To improve antigen entry, one promising approach is the use of cell penetrating peptides (CPPs). However, most studies use a covalent binding of the CPP with the antigen. In the present study, we focused on the C-terminal domain of Vpr which was previously demonstrated to efficiently deliver plasmid DNA into cells. We provide evidence that the peptides Vpr55-91 and Vpr55-82 possess the capacity of delivering proteins and epitopes into cell lines as well as into human primary dendritic cells, without the necessicity for a chemical linkage. Moreover, immunization of HLA-A2 transgenic mice with Vpr55-91 as the sole adjuvant is able to induce antigen-specific cytotoxic T lymphocytes against multiple tumor epitopes.
Assuntos
Peptídeos Penetradores de Células/imunologia , Produtos do Gene vpr/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Apresentação de Antígeno/imunologia , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Células CHO , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Linhagem Celular , Peptídeos Penetradores de Células/genética , Cricetulus , Sistemas de Liberação de Medicamentos , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Produtos do Gene vpr/genética , Antígeno HLA-A2/genética , Antígeno HLA-A2/imunologia , Células Hep G2 , Humanos , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Transporte Proteico , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologiaRESUMO
OBJECTIVE: We aimed to establish the current status of hepatitis B virus (HBV) vaccination in prison. METHODS: We carried out two evaluations within a 1-year interval with inmates incarcerated for 6 to 12 months. A monitoring process was introduced in-between the two evaluations. RESULTS: We included 231 inmates. Overall, 42.9% were immunized because of a previous vaccination and 14.3% because of a previous exposure. Inmates born in an area of medium or high endemicity for HBV were significantly more exposed to HBV. The proportion of non-immunized inmates was 42.8% at the time of incarceration and 27.5% after 6 to 12 months. Vaccination coverage with two doses, after 6 to 12 months, was 63% among patients who were initially non-immunized. CONCLUSION: The recently developed accelerated vaccination schedule should help improve HBV vaccination coverage.
Assuntos
Vacinas contra Hepatite B , Hepatite B/prevenção & controle , Prisões , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Vacinação/estatística & dados numéricosRESUMO
This review focuses on genes that control ß-cell targeting in autoimmune, type 1-dependent, diabetes (T1D) and on insulin as the major autoantigen recognized by T lymphocytes throughout the disease process. T1D associates with multiple gene variants. Beyond genes that predispose to general failure of immune tolerance to self, loci identified by the analysis of crosses between non-obese diabetic (NOD) and conventional mouse strains harbour genes that control ß-cell targeting or the deviation of autoimmunity towards other tissues. We report here the role of genes encoding co-activation molecules involved in the activation of T lymphocytes, ICOS and ICOS ligand (B7RP1). NOD mice which are deficient in either of these two molecules are protected from diabetes, but instead develop a neuromuscular autoimmune disease. We also report the characterization in humans of T lymphocytes that are specific for major ß-cell autoantigens, especially insulin. This opens the way towards new bioassays in the diagnosis of autoimmunity and towards autoantigen-specific immunotherapy in T1D. In order to develop a new preclinical model of T1D that would allow testing insulin epitopes to induce immune tolerance in vivo, we developed a mouse that is deficient in endogenous major histocompatibility complex class I and class II genes and deficient for the two murine insulin genes and that express human class I, class II and insulin genes.
Assuntos
Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Linfócitos T/fisiologia , Animais , Autoimunidade/genética , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Humanos , Tolerância Imunológica/genética , Células Secretoras de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos NODRESUMO
AIMS/HYPOTHESIS: Anti-zinc transporter (ZnT)8 autoantibodies are commonly detected in type 1 diabetic patients. We hypothesised that ZnT8 is also recognised by CD8(+) T cells and aimed to identify HLA-A2 (A*02:01)-restricted epitope targets. METHODS: Candidate epitopes were selected by ZnT8 plasmid DNA immunisation of HLA-A2/DQ8 transgenic mice and tested for T cell recognition in peripheral blood mononuclear cells of type 1 diabetic, type 2 diabetic and healthy participants by IFN-γ enzyme-linked immunospot. RESULTS: White HLA-A2(+) adults (83%) and children (60%) with type 1 diabetes displayed ZnT8-reactive CD8(+) T cells that recognised a single ZnT8(186-194) (VAANIVLTV) epitope. This ZnT8(186-194)-reactive fraction accounted for 50% to 53% of total ZnT8-specific CD8(+) T cells. Another sequence, ZnT8(153-161) (VVTGVLVYL), was recognised in 20% and 25% of type 1 diabetic adults and children, respectively. Both epitopes were type 1 diabetes-specific, being marginally recognised by type 2 diabetic and healthy participants (7-12% for ZnT8(186-194), 0% for ZnT8(153-161)). CONCLUSIONS/INTERPRETATION: ZnT8-reactive CD8(+) T cells are predominantly directed against the ZnT8(186-194) epitope and are detected in a majority of type 1 diabetic patients. The exceptional immunodominance of ZnT8(186-194) may point to common environmental triggers precipitating beta cell autoimmunity.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Proteínas de Transporte de Cátions/imunologia , Diabetes Mellitus Tipo 1/imunologia , Epitopos de Linfócito T/imunologia , Antígeno HLA-A2/imunologia , Adolescente , Adulto , Animais , Autoanticorpos/genética , Linfócitos T CD4-Positivos/imunologia , Proteínas de Transporte de Cátions/genética , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/genética , Mapeamento de Epitopos , Epitopos de Linfócito T/genética , Feminino , Antígeno HLA-A2/genética , Humanos , Lactente , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Transportador 8 de ZincoRESUMO
Bronchiolitis obliterans (BO) is a severe complication of hematopoietic stem cell transplantation (HSCT). It is considered as a respiratory manifestation of chronic graft-versus-host disease. It is quite similar to the bronchiolitis obliterans after lung transplantation. Classical therapy associates steroids and immunosuppressive drugs, however theses procedure showed a modest efficacy and have an important morbidity. Recent progresses in the physiopathology of BO post-HSCT allow to use new treatments: mTOR inhibitors, immunotherapy, extra-corporeal photochemotherapy, and bronchial anti-inflammatory effects of azithromycin, statins or antileucotriens. This review will focus on the use of these new therapies in BO post-HSCT.
Assuntos
Bronquiolite Obliterante/etiologia , Bronquiolite Obliterante/fisiopatologia , Bronquiolite Obliterante/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Fatores de RiscoRESUMO
The profile of recurrent ischemic strokes has not been much investigated. The aim of this study was to evaluate how the therapeutic strategies recommended for secondary prevention after an ischemic stroke are implemented in the real world of clinical practice. All patients admitted for a recurrent ischemic stroke or TIA were prospectively registered. The etiology was determined according to the TOAST classification. The risk factors and cardiovascular treatment at the time of the recurrence were recorded. A total of 168 patients were evaluated. Most of the patients (61%) recurred after 1 year. The recurrent stroke was not associated with a particular etiological subtype. The most frequent risk factor was hypertension (79%), followed by hypercholesterolemia (43%), smoking (25%), and diabetes (22%). Most of the patients had more than 1 risk factor (84%). Hypertension was not satisfactorily controlled in 38% of patients, hypercholesterolemia in 42%, and diabetes in 59%. A significant minority of patients (15%) were not taking any antithrombotic agent despite a history of stroke or TIA. Only 34% of the cases with a known atrial fibrillation were on anticoagulant therapy and the International Normalized Ratio was < 2.0 in 71% of them. In conclusion, stroke prevention needs to be improved by better implementation of therapeutic strategies in clinical practice. The patients should also be better informed about target values as well as the importance of physical activity and smoking cessation.
Assuntos
Fármacos Cardiovasculares/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Complicações do Diabetes , Feminino , Humanos , Hiperlipidemias/complicações , Hiperlipidemias/tratamento farmacológico , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Prevenção Secundária , Fumar/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Adulto JovemRESUMO
The tetracycline-controlled transcription system (Tet-on) is widely used to regulate gene expression in mammalian cells. In gene therapy applications, immune responses to Tet-on proteins such as the rtTA transcription factor have been reported, raising concerns about their occurrence in humans. To monitor the HLA class I cytolytic responses against Tet-on regulators, we characterized the immunogenic CD8+ epitopes within rtTA and tTS regulators using HLA-A*0201 class I transgenic mice. Epitope prediction programs, HLA-A*0201 binding assays, and peptide immunization were used to select a set of immunogenic peptides within rtTA and tTS sequences. To identify further the rejection epitopes, we expressed Tet-on protein components in vivo and found a single dominant rtTA186 CTL epitope in the rtTA tetracycline repressor domain. Target cells expressing rtTA were susceptible to CTL lysis, and rtTA expression compromised muscle transgene engraftment. To reduce the occurrence of immune responses to rtTA protein, we mutated the dominant rtTA186 epitope and found that this leads to the appearance of subdominant epitopes. As a result, we think that an epitope modification strategy is not applicable to blunt the immune response in this model. Moreover, the identification of HLA-A*0201 rtTA epitopes allowed us to demonstrate here that the delivery of the Tet-on system with weakly immunogenic rAAV vectors does not trigger primary CTL responses in mice, in contrast to DNA transfer. Altogether, the existence of HLA-A*0201 rtTA epitopes may lead to the occurrence of immune responses depending on vectors and local inflammation in gene therapy applications involving rtTA-based regulatory systems.
Assuntos
Epitopos de Linfócito T/imunologia , Regulação da Expressão Gênica , Antígenos HLA-A/metabolismo , Linfócitos T Citotóxicos/imunologia , Tetraciclina/farmacologia , Transativadores/imunologia , Transgenes , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Doxiciclina/farmacologia , Epitopos de Linfócito T/genética , Expressão Gênica/efeitos dos fármacos , Terapia Genética/métodos , Antígenos HLA-A/genética , Antígeno HLA-A2 , Epitopos Imunodominantes/genética , Epitopos Imunodominantes/imunologia , Camundongos , Camundongos Transgênicos , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Mutagênese/genética , Mutação/genética , Peptídeos/genética , Peptídeos/imunologia , Transativadores/genética , Transgenes/genéticaRESUMO
Bladder carcinoma is the fourth most common cancer in men and the eighth most common cancer among women. Our study is aimed to characterise tumour-associated antigen peptides of transitional cell carcinoma of the bladder (TCC). A DNA micro-array-based differential display analysis of 10 000 genes was carried out, and MAGE-A8 gene expression was detected in the tumour, and not in the normal bladder. High occurrence of MAGE-A8 expression was observed in fresh tumour samples (17 out of 23) and TCC lines (four of eight). The MAGE-A8 protein sequence was screened for HLA-A2.1-binding motifs, six potential peptides were synthesised, and peptides binding to HLA-A2.1 were assured. Immunogenicity and antigenicity of the MAGE-A8 peptides were examined in the HHD system, murine class I MHC knockout mice, transgenic for HLA-A2.1. The MAGE-A8 peptide immunogenicity was examined in three modes of vaccination, delivered intranasally with cholera toxin, injected into the tail base with complete Freund's adjuvant (CFA), or presented directly as loaded onto cell surface HLA-A2.1 molecules. Two peptides, 8.1 and 8.3, induce CTL that kills the T24 TCC line in vitro, and prime human lymphocyte response of healthy donors. These results demonstrate the potential use of the MAGE-A8 peptides for specific immunotherapy of TCC.
Assuntos
Antígenos de Neoplasias/genética , Carcinoma de Células de Transição/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética , Oligopeptídeos/genética , Neoplasias da Bexiga Urinária/genética , Animais , Antígenos de Neoplasias/imunologia , Carcinoma de Células de Transição/patologia , Toxina da Cólera/administração & dosagem , Citotoxicidade Imunológica , Adjuvante de Freund , Perfilação da Expressão Gênica , Antígeno HLA-A2/imunologia , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteínas de Neoplasias/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Oligopeptídeos/farmacologia , Linfócitos T/imunologia , Neoplasias da Bexiga Urinária/patologia , Vacinação , Microglobulina beta-2/genética , Microglobulina beta-2/fisiologiaRESUMO
Dystrophin-based gene therapy treatments aimed at correcting the Duchenne muscular dystrophy phenotype require stable expression of normal dystrophin (DYST) protein in myocytes without immune responses, which would compromise long-term expression. To predict cytotoxic T-cell-mediated responses elicited by transgenes, we used here H-2-negative HLA-A*0201 transgenic mice and identified human DYST epitopes, which elicit HLA-A*0201-restricted cytotoxic T cell activities. Among a series of eight peptides predicted from the human DYST sequence, not shared with the endogenous mouse DYST sequence, four of them were able to bind to HLA-A*0201 molecules and to induce cytotoxic T lymphocyte (CTL) responses. After human DYST DNA transfer in muscle of HLA-A*0201 mice, only the human DYST1281 epitope, located in the spectrin-like repeat 9 domain, induced strong CD8(+) CTL responses. Using the corresponding human DYST1281 peptide/HLA-A*0201 tetramer, we detected human DYST1281-specific CD8(+) T cells in peripheral lymphoid organs and blood of HLA-A*0201 mice injected with human DYST DNA. Our results demonstrate that muscle injection with human DYST DNA systematically triggers CTL responses against this HLA-A*0201-restricted human DYST1281 peptide, which is present in long human DYST isoforms. Identification of such immunodominant human DYST epitopes and use of peptide/HLA tetramers will allow the immunomonitoring of CTL responses in HLA-phenotyped Duchenne muscular dystrophy patients undergoing gene therapy. Finally, the knowledge of HLA-A*0201-restricted human DYST peptides will be of importance to test, in mouse models, new immunomodulatory interventions allowing long-term engraftment of human dystrophin.
Assuntos
Distrofina/imunologia , Epitopos/imunologia , Terapia Genética/métodos , Antígenos HLA-A/imunologia , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/terapia , Animais , Células Cultivadas , Distrofina/química , Distrofina/genética , Epitopos/química , Epitopos/genética , Citometria de Fluxo , Antígeno HLA-A2 , Humanos , Camundongos , Camundongos Transgênicos , Distrofia Muscular de Duchenne/imunologia , Linfócitos T Citotóxicos/imunologiaRESUMO
Parathyroid hormone-related protein (PTH-rP), a secreted protein produced by prostate carcinoma and other epithelial cancers, is considered a key agent for the development of bone metastases. We investigated the construct GC90/IRIV, composed of immunopotentiating reconstituted influenza virosomes (IRIV) containing PTH-rP gene plasmids (GC90), as a potential tool for human anticancer immunotherapy into humanised mice transgenic for HLA-A(*)02.01, the human-beta2 microglobulin, and the human CD8alpha molecule. Intranasal administration of GC90/IRIV resulted in the induction of a PTH-rP-specific multiepitope cytotoxic T-cell (CTL) response. Cytotoxic T cells derived from vaccinated mice were capable of lysing in vitro syngenic murine PTH-rP transfectants and human HLA-A((*))02.01(+)/PTH-rP(+) prostate carcinoma LNCaP cells as well. The immune response capacity and the absence of any sign of toxicity and/or autoimmunity in vivo suggest the GC90/IRIV vaccine as a valid tool for active specific immunotherapy of human cancers and metastases overexpressing PTH-rP.
Assuntos
Vacinas Anticâncer , Camundongos Transgênicos , Hormônios Peptídicos/genética , Animais , Carcinoma/genética , Carcinoma/imunologia , Humanos , Imunoterapia , Masculino , Camundongos , Proteína Relacionada ao Hormônio Paratireóideo , Fragmentos de Peptídeos , Hormônios Peptídicos/biossíntese , Hormônios Peptídicos/farmacologia , Plasmídeos , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Linfócitos T Citotóxicos , Células Tumorais CultivadasRESUMO
HER-2/neu is a tumor-associated antigen overexpressed in a large variety of human tumors. Eight HER-2/neu peptides displaying HLA-A*0201 anchoring motifs were selected and tested for their binding affinity to HLA-A*0201 and their capacity to elicit cytotoxic T lymphocyte (CTL) responses in both HLA-A*0201 transgenic mice and in HLA-A*0201(+) healthy donors. Two high-affinity (p5 and p48) and one intermediate-affinity (p1023) peptides triggered CTL responses in both transgenic mice and humans, comparable to those observed for the well-known HER2/neu dominant peptide p369. CTL induced in transgenic mice lysed HLA-A*0201(+) RMA cells infected with recombinant HER-2/neu but not cells infected with wild-type vaccinia virus. Human CTL lysed HLA-A*0201(+) HER-2/neu(+) tumor cells of different origins (breast, colon, lung and renal cancer) irrespective of the expression levels of HER-2/neu. Importantly, primed CTL specific for these epitopes were detected in freshly isolated tumor-infiltrating lymphocytes from three renal cell carcinoma patients. Therefore, the HER-2/neu peptides p5, p48 and p1023 may be good candidates for immunotherapy of a broad spectrum of tumors, including renal cell carcinoma.
Assuntos
Carcinoma de Células Renais/imunologia , Neoplasias Renais/imunologia , Receptor ErbB-2/imunologia , Animais , Carcinoma de Células Renais/terapia , Epitopos , Antígenos HLA-A/metabolismo , Humanos , Imunoterapia , Neoplasias Renais/terapia , Camundongos , Linfócitos T Citotóxicos/imunologiaRESUMO
The immunogenicity of the Hepatitis C virus (HCV) nonstructural protein 3 (NS3) was investigated using different DNA-based strategies and a preclinical mouse model transgenic for the HLA-A2.1 molecule. Plasmids expressing NS3 either as a wild-type protein, as a fusion with murine lysosome-associated-membrane protein-1 specific sequences, or under the control of the Semliki Forest virus replicase were evaluated in vitro and in vivo. All plasmids were shown to express the expected size protein. These 3 NS3-expressing vaccines induced overall comparable levels of CTLs when measured at different times postvaccination although mice injected with the NS3-LAMP expressing plasmid showed a particularly homogeneous and overall vigorous response (specific lysis ranged from 60% to 90 % for an E:T ratio of 33.3:1 with a mean CTL precursor frequency of 1:2.10(5) cells). Out of the four HLA-A2.1-restricted NS3 epitopes previously described in HCV infected patients (aa 1073-1081, aa 1406-1415; aa 1169-1177 and aa 1287-1296), the NS3-DNA generated CTLs were predominantly targeted at the aa 1073-1081 epitope. Peptide-based immunization showed that the mouse repertoire was intact for all epitopes tested except one (aa 1287-1296). In conclusion, the 3 NS3-DNA vaccines although based on different mode of action, shared a comparable efficacy at inducing CTL. Surprisingly, the breadth of such response was restricted to a single, major epitope.
Assuntos
Epitopos/imunologia , Antígeno HLA-A2/análise , Linfócitos T Citotóxicos/imunologia , Vacinas de DNA/imunologia , Proteínas não Estruturais Virais/imunologia , Células 3T3 , Animais , Formação de Anticorpos , Feminino , Antígeno HLA-A2/genética , Imunização , Interferon gama/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Transgênicos/genética , Linfócitos T/metabolismoRESUMO
HFE is a nonclassical class I major histocompatibility complex (MHC) molecule that is mutated in the autosomal recessive iron overload disease hereditary hemochromatosis. There is evidence linking HFE with reduced iron uptake by the transferrin receptor (TfR). Using a panel of HFE and TfR monoclonal antibodies to examine human HFE (hHFE)-expressing cell lines, we demonstrate the expression of stable and fully glycosylated TfR-free and TfR-associated hHFE/beta2m complexes. We show that both the stability and assembly of hHFE complexes can be modified by the human cytomegalovirus (HCMV) viral protein US2, known to interfere with the expression of classical class I MHC molecules. HCMV US2, but not US11, targets HFE molecules for degradation by the proteasome. Whether this interference with the regulation of iron metabolism by a viral protein is a means of potentiating viral replication remains to be determined. The reduced expression of classical class I MHC and HFE complexes provides the virus with an efficient tool for altering cellular metabolism and escaping certain immune responses.
Assuntos
Citomegalovirus/fisiologia , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Ferro/metabolismo , Proteínas de Membrana , Proteínas do Envelope Viral/fisiologia , Sequência de Aminoácidos , Células HeLa , Proteína da Hemocromatose , Homeostase , Humanos , Dados de Sequência Molecular , Proteínas de Ligação a RNA/fisiologia , Receptores da Transferrina/análise , Proteínas Recombinantes/metabolismo , Vaccinia virus/genética , Proteínas Virais/fisiologiaRESUMO
HLA-A*0201 transgenic, H-2D(b)/mouse beta2-microglobulin double-knockout mice were used to compare and optimize the immunogenic potential of 17HIV 1-derived,HLA-A0201-restricted epitopic peptides. A tyrosine substitution in position 1 of the epitopic peptides, which increases both their affinity for and their HLA-A0201 molecule stabilizing capacity, was introduced in a significant proportion, having verified that such modifications enhance their immunogenicity in respect of their natural antigenicity. Based on these results, a 13-polyepitope construct was inserted in the pre-S2 segment of the hepatitis B middle glycoprotein and used for DNA immunization. Long-lasting CTL responses against most of the inserted epitopes could be elicited simultaneously in a single animal with cross-recognition in several cases of their most common natural variants.