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1.
Stud Health Technol Inform ; 270: 1151-1155, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32570561

RESUMO

BACKGROUND: According to the Swiss Law on Research in Humans, the reuse of routinely collected genetic and non-genetic data and samples from patients for research purposes requires the consent of patients. Unfortunately, the so far established paper-based processes are intrinsically linked to the hospital admission process, labour intensive and not yielding the targeted return rates. Therefore, the overall goal of the presented SPHN project is to increase patient reach by providing hospitals with a patient-centric, user-friendly and admission-independent electronic general consent pathway. As part of the project, feasibility of different digital pathways was evaluated in a usability testing. METHODS: Based on a nationwide harmonised template, a mobile centric progressive web application was developed by the Department of Clinical Research Basel. Usability of the application and according user journeys were evaluated at all partner hospitals. Two options of giving consent were explored using 1) patients' smartphones without any involvement of hospital personnel and 2) a hospital device (tablet) with explicit confirmation of patient identity by hospital personnel. Participant signatures were captured as a picture of a handwritten signature on paper taken with the camera of the smartphone or tablet. Usability issues and feedback of participants were documented directly after usability testing. RESULTS: In total, 122 users agreed to participate in the usability testing using a tablet or smartphone. The general consent request workflow on the smartphone or tablet was regarded as user friendly and easy to navigate by 96% of all participants. However, capturing a picture of a handwritten signature resulted in usability issues in multiple cases, i.e. due to missing pen or paper. CONCLUSION: Usability testing of our prototype application showed a broad acceptance of participants regarding the use of mobile electronic devices to give general consent. Therefore, we believe that easy-to-use digital general consent processes provide effective means to increase the patient pool for health-related research. Further discussions with legislative bodies are required to find patient centric, feasible and legally acceptable solutions in the specific case of electronic general consent for the near future.


Assuntos
Interface Usuário-Computador , Eletrônica , Humanos , Consentimento Livre e Esclarecido , Aplicativos Móveis , Smartphone
2.
J Immunother ; 33(8): 848-58, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20842051

RESUMO

Induction of cytotoxic CD8 T-cell responses is enhanced by the exclusive presentation of antigen through dendritic cells, and by innate stimuli, such as toll-like receptor ligands. On the basis of these 2 principles, we designed a vaccine against melanoma. Specifically, we linked the melanoma-specific Melan-A/Mart-1 peptide to virus-like nanoparticles loaded with A-type CpG, a ligand for toll-like receptor 9. Melan-A/Mart-1 peptide was cross-presented, as shown in vitro with human dendritic cells and in HLA-A2 transgenic mice. A phase I/II study in stage II-IV melanoma patients showed that the vaccine was well tolerated, and that 14/22 patients generated ex vivo detectable T-cell responses, with in part multifunctional T cells capable to degranulate and produce IFN-γ, TNF-α, and IL-2. No significant influence of the route of immunization (subcutaneous versus intradermal) nor dosing regimen (weekly versus daily clusters) could be observed. It is interesting to note that, relatively large fractions of responding specific T cells exhibited a central memory phenotype, more than what is achieved by other nonlive vaccines. We conclude that vaccination with CpG loaded virus-like nanoparticles is associated with a human CD8 T-cell response with properties of a potential long-term immune protection from the disease.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Vacinas Anticâncer , Melanoma/terapia , Neoplasias Cutâneas/terapia , Subpopulações de Linfócitos T/metabolismo , Vacinas de Partículas Semelhantes a Vírus , Adulto , Idoso , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Diferenciação Celular , Células Cultivadas , Feminino , Antígeno HLA-A2/genética , Antígeno HLA-A2/metabolismo , Humanos , Memória Imunológica , Ativação Linfocitária , Antígeno MART-1/química , Antígeno MART-1/imunologia , Masculino , Melanoma/imunologia , Melanoma/patologia , Melanoma/fisiopatologia , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Nanopartículas/química , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/imunologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/fisiopatologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Resultado do Tratamento
3.
PLoS One ; 3(6): e2547, 2008 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-18575629

RESUMO

BACKGROUND: Tobacco dependence is the leading cause of preventable death and disabilities worldwide and nicotine is the main substance responsible for the addiction to tobacco. A vaccine against nicotine was tested in a 6-month randomized, double blind phase II smoking cessation study in 341 smokers with a subsequent 6-month follow-up period. METHODOLOGY/PRINCIPAL FINDINGS: 229 subjects were randomized to receive five intramuscular injections of the nicotine vaccine and 112 to receive placebo at monthly intervals. All subjects received individual behavioral smoking cessation counseling. The vaccine was safe, generally well tolerated and highly immunogenic, inducing a 100% antibody responder rate after the first injection. Point prevalence of abstinence at month 2 showed a statistically significant difference between subjects treated with Nicotine-Qbeta (47.2%) and placebo (35.1%) (P = 0.036), but continuous abstinence between months 2 and 6 was not significantly different. However, in subgroup analysis of the per-protocol population, the third of subjects with highest antibody levels showed higher continuous abstinence from month 2 until month 6 (56.6%) than placebo treated participants (31.3%) (OR 2.9; P = 0.004) while medium and low antibody levels did not increase abstinence rates. After 12 month, the difference in continuous abstinence rate between subjects on placebo and those with high antibody response was maintained (difference 20.2%, P = 0.012). CONCLUSIONS: Whereas Nicotine-Qbeta did not significantly increase continuous abstinence rates in the intention-to-treat population, subgroup analyses of the per-protocol population suggest that such a vaccination against nicotine can significantly increase continuous abstinence rates in smokers when sufficiently high antibody levels are achieved. Immunotherapy might open a new avenue to the treatment of nicotine addiction. TRIAL REGISTRATION: Swiss Medical Registry 2003DR2327; ClinicalTrials.gov NCT00369616.


Assuntos
Nicotina/imunologia , Abandono do Hábito de Fumar/métodos , Vacinas/administração & dosagem , Adulto , Formação de Anticorpos , Método Duplo-Cego , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Placebos , Vacinas/imunologia
4.
J Immunol ; 175(10): 7009-20, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16272362

RESUMO

Immune responses contribute to the pathogenesis of vitiligo and target melanoma sometimes associated with vitiligo-like depigmentation in some melanoma patients. We analyzed the sera from patients with vitiligo and cutaneous melanoma for reactivity toward tyrosinase peptide sequences 1) endowed with low level of similarity to human proteome, and 2) potentially able to bind HLA-DR1 Ags. We report that the tyrosinase autoantigen was immunorecognized with the same molecular pattern by sera from vitiligo and melanoma patients. Five autoantigen peptides composed the immunodominant anti-tyrosinase response: aa95-104FMGFNCGNCK; aa175-182 LFVWMHYY; aa176-190FVWMHYYVSMDALLG; aa222-236IQKLTGDENFTIPYW, and aa233-247 IPYWDWRDAEKCDIC. All of the five antigenic peptides were characterized by being (or containing) a sequence with low similarity level to the self proteome. Sera from healthy subjects were responsive to aa95-104FMGFNCGNCK, aa222-236IQKLTGDENFTIPYW, and aa233-247 IPYWDWRDAEKCDIC, but did not react with the aa175-182LFVWMHYY and aa176-190FVWMHYYVSMDALLG peptide sequences containing the copper-binding His180 and the oculocutaneous albinism I-A variant position F176. Our results indicate a clear-cut link between peptide immunogenicity and low similarity level of the corresponding amino acid sequence, and are an example of a comparative analysis that might allow to comprehensively distinguish the epitopic peptide sequences within a disease from those associated to natural autoantibodies. In particular, these data, for the first time, delineate the linear B epitope pattern on tyrosinase autoantigen and provide definitive evidence of humoral immune responses against tyrosinase.


Assuntos
Antígeno HLA-DR1/metabolismo , Melanoma/enzimologia , Melanoma/imunologia , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/imunologia , Vitiligo/enzimologia , Vitiligo/imunologia , Alelos , Sequência de Aminoácidos , Autoanticorpos/sangue , Autoantígenos/genética , Autoantígenos/metabolismo , Estudos de Casos e Controles , Epitopos/genética , Epitopos/metabolismo , Frequência do Gene , Antígeno HLA-DR1/classificação , Antígeno HLA-DR1/genética , Humanos , Imuno-Histoquímica , Melanoma/genética , Dados de Sequência Molecular , Monofenol Mono-Oxigenase/metabolismo , Ligação Proteica , Proteômica , Vitiligo/genética
5.
Dermatology ; 211(4): 318-24, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16286739

RESUMO

BACKGROUND: Apoptotic pathway aberrations are reported as important tumor progression factors in melanoma. OBJECTIVE: Effect of soluble Fas ligand (sFasL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on short-term cultured melanoma cell viability from different stages of melanoma. RESULTS: Recombinant human FasL reduced viability after 18 h in a dose-dependent manner in 4 of 5 cell cultures from primary tumors and 1 of 9 cell cultures from metastatic melanoma (67.5 vs. 96.4%, p = 0.007). DNA fragmentation on flow cytometry confirmed apoptosis. Incubation with TRAIL had no effect on melanoma cell viability. Immunohistochemistry showed Fas in 3 of 4 primary and in 6 of 7 metastatic lesions, no FasL in primary lesions, and FasL in 5 of 7 metastatic lesions. CONCLUSION: Melanoma short-term cell cultures from primary tumors show decreased viability under FasL, but not TRAIL stimulation rather than short-term cell cultures derived from metastases.


Assuntos
Antígenos de Superfície/análise , Apoptose/efeitos dos fármacos , Melanoma/patologia , Glicoproteínas de Membrana/farmacologia , Fatores de Necrose Tumoral/farmacologia , Receptor fas/farmacologia , Proteínas Reguladoras de Apoptose/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA , Relação Dose-Resposta a Droga , Proteína Ligante Fas , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Células Jurkat , Ligantes , Metástase Linfática/patologia , Melanoma/secundário , Glicoproteínas de Membrana/análise , Estadiamento de Neoplasias , Ligante Indutor de Apoptose Relacionado a TNF , Fatores de Tempo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia , Fatores de Necrose Tumoral/análise , Receptor fas/análise
6.
Eur J Immunol ; 35(7): 2031-40, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15971275

RESUMO

Nicotine is the principal addictive component in tobacco, and following uptake acts in the central nervous system. The smoking-cessation efforts of most smokers fail because a single slip often delivers sufficient nicotine to the brain to reinstate the drug-seeking behaviour. Blocking nicotine from entering the brain by induction of specific antibodies may be an effective means to prevent such relapses. The hapten nicotine was coupled to virus-like particles (VLP) formed by the coat protein of the bacteriophage Qb. In preclinical experiments, this Nicotine-Qb VLP (NicQb) vaccine induced strong antibody responses. After intravenous nicotine challenge, vaccinated mice exhibited strongly reduced nicotine levels in the brain compared with control mice. In a phase I study, 32 healthy non-smokers were immunized with NicQb. The vaccine was safe and well-tolerated. All volunteers who received NicQb showed nicotine-specific IgM antibodies at day 7 and nicotine-specific IgG antibodies at day 14. Antibody levels could be boosted by a second injection or the addition of Alum as an adjuvant and the antibodies had a high affinity for nicotine. These data suggest that antibodies induced by NicQb may prevent relapses by sequestering nicotine in the blood of immunized smokers.


Assuntos
Imunoglobulina G/biossíntese , Nicotina/imunologia , Tabagismo/imunologia , Tabagismo/prevenção & controle , Vacinas/administração & dosagem , Adolescente , Adulto , Allolevivirus/genética , Allolevivirus/imunologia , Animais , Método Duplo-Cego , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Vacinas/efeitos adversos , Vacinas/genética , Vacinas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
7.
Exp Dermatol ; 14(7): 543-50, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15946243

RESUMO

Using non-self discrimination as a driving force in generating peptide immunogenicity, we have developed a computer-assisted proteomic analysis in order to identify the protein antigenic regions that have evoked humoral response. The purpose of this study was to further validate the computational analysis for melanoma-associated antigens and, at the same time, to assess the efficacy of the methodology in defining antigenic regions of autoantigens associated to autoimmune diseases. To achieve this two-fold objective, we have examined the enzyme tyrosinase, a protein that represents an important autoantigen in patients with vitiligo or melanoma. Here, we report that the antigenic linear determinant of the monoclonal antibody (Mab) T311 raised against the melanoma/vitiligo tyrosinase autoantigen is located in the low similarity 15-mer amino acid sequence tyrosinase 233-247 IPYWDWRDAEKCDIC, within the fragment 237-247. These data confirm non-similarity to the host proteome as a factor that participates in shaping peptide immune reactivity and may be a first step towards designing tyrosinase antigenic peptides to be used for (i) direct neutralization of harmful melanocytes-attacking autoantibodies in vitiligo, or (ii) production of antibodies against tyrosinase-positive melanomas. Moreover tyrosinase peptide antigens might be used as key tools in studying the boundaries between self-tolerance and autoimmunity phenomena.


Assuntos
Anticorpos Monoclonais , Monofenol Mono-Oxigenase/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Mapeamento de Epitopos , Epitopos/química , Epitopos/genética , Antígenos H-2/metabolismo , Humanos , Melanoma/imunologia , Camundongos , Dados de Sequência Molecular , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Proteômica
8.
Exp Dermatol ; 14(7): 491-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15946236

RESUMO

The efficiency of melanoma immunotherapy appears to depend on both melanoma- and immune system-specific factors. Melanoma-specific factors include melanoma-associated antigen (MAA) expression as well as HLA class I molecule expression. We investigated the expression of five MAA - Melan-A/MART-1, tyrosinase, gp100, MAGE-1 and MAGE-3 - by means of FACS analysis in 50 melanoma cell cultures and compared them to the cultures of human foreskin-derived melanocytes and melanoma cell line UKRV-Mel2. Melan-A, tyrosinase and gp100 expression was frequently reduced in melanoma cell cultures, compared to that in foreskin melanocytes, whereas MAGE-1 and MAGE-3 expression showed variable degree of upregulation, compared to that in foreskin melanocytes. The expression of all tested MAA demonstrated high interindividual variability. We further show that cell cultures derived from the same tissue sample are oligoclonal in nature, by demonstrating the presence of up to three cell populations bearing distinct MAA profile. Analysing samples derived from the same patient but each at a different time point, we show that MAA expression profile changes over time either in positive (increase) or in negative (decrease) direction. Finally, we demonstrate that brain metastasis-derived cell cultures significantly overexpress Melan-A and MAGE-3, compared to primary tumours and other metastatic sites (P-value range: 0.05-0.001). Elucidation of the MAA expression patterns and the kinetics within the same patient as well as during the course of the disease may help improve current and develop new immunotherapeutic strategies.


Assuntos
Antígenos de Neoplasias/metabolismo , Melanoma/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunoterapia , Interferon Tipo I/uso terapêutico , Cinética , Antígeno MART-1 , Masculino , Melanoma/metabolismo , Melanoma/secundário , Melanoma/terapia , Antígenos Específicos de Melanoma , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/imunologia , Monofenol Mono-Oxigenase/metabolismo , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/metabolismo , Proteínas Recombinantes , Células Tumorais Cultivadas , Antígeno gp100 de Melanoma
9.
J Invest Dermatol ; 123(4): 670-5, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15373771

RESUMO

An efficient strategy is presented for the identification of antigenic sequences in the context of given MHC molecules of interest. The proteomic analysis of the antigenic peptide repertoire is described and demonstrated by using high-molecular weight melanoma-associated antigen. The identification of the epitopic sequence of a monoclonal antibody raised against the 250 kDa tumor associated antigen was reached by using only seven short synthetic peptide fragments, instead of the 155 non-overlapping 15-mer peptides theoretically necessary as minimum screening library. The present result has been obtained by applying as driving criteria the analysis of the peptide affinity to MHC class II molecules and the non-self discrimination concept.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/química , Antígenos de Neoplasias/imunologia , Epitopos/química , Proteômica , Sequência de Aminoácidos , Antígenos de Neoplasias/metabolismo , Bases de Dados de Proteínas , Epitopos/imunologia , Glicosilação , Humanos , Dados de Sequência Molecular
10.
Melanoma Res ; 14(4): 257-62, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15305155

RESUMO

The lack of melanoma-associated antigen (MAA) expression has been associated with the reduced overall survival in melanoma patients. In order to investigate whether the MAA expression detected on cell cultures established from melanoma patients might relate to the overall survival in these patients, we screened primary cell cultures derived from 37 melanoma metastases for the expression of five known MAA: Melan-A, tyrosinase, gp-100, MAGE-1 and MAGE-3 by polymerase chain reaction (PCR) and fluorescence-activated cell sorting (FACS). MAA expression detected by PCR was found at a high percentage in evaluated melanoma cell lines: 25 of 28 (89%) were positive for Melan-A, 22 of 28 (79%) were positive for tyrosinase, 26 of 28 (93%) were positive for gp-100, and 18 of 28 (64%) were positive for MAGE-3 expression. Using the FACS method the percentage of MAA-positive cell lines was much lower: 14 of 31 (45%) cell lines were positive for Melan-A, eight of 31 (26%) were positive for tyrosinase, 13 of 31 (42%) were positive for gp-100, six of 31 (19%) were positive for MAGE-1, and 14 of 31 (45%) were positive for MAGE-3 expression. Kaplan-Meier survival analysis demonstrated that the patients whose cell lines were positive for Melan-A expression by PCR had significantly longer overall survival time as Melan-A PCR-negative cases (P=0.0038). This could not be shown for any of the markers tested by FACS. Our results suggest that the expression of Melan-A/MART-1 in patient-derived cell cultures may help to identify a group of melanoma patients with prolonged survival.


Assuntos
Regulação Neoplásica da Expressão Gênica , Melanoma/metabolismo , Melanoma/patologia , Proteínas de Neoplasias/metabolismo , Adulto , Idoso , Antígenos de Neoplasias , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Feminino , Citometria de Fluxo , Humanos , Antígeno MART-1 , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas
11.
Int J Cancer ; 111(5): 720-6, 2004 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-15252841

RESUMO

We analyzed the sera of patients with melanoma to define the human humoral autoantibody profile towards HMW-MAA. Computational proteome scanning using the non-self-discrimination principle as a guide led to the individuation of the low-similarity HMW-MAA781-789RATVWMLRL peptide fragment as an immunodominant B-cell epitope. Linear B-cell determinant individuation was experimentally validated by dot blot immunoassay and NMR spectroscopy analysis. Regulation of physiologic self-reactivity by the non-self-discrimination principle is discussed.


Assuntos
Antígenos de Neoplasias/química , Antígenos de Neoplasias/imunologia , Autoanticorpos/análise , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Biologia Computacional , Epitopos , Humanos , Imunoensaio , Espectroscopia de Ressonância Magnética , Proteoma , Análise de Sequência de Proteína
12.
Clin Cancer Res ; 9(7): 2744-54, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12855655

RESUMO

PURPOSE: Cutaneous anaplastic large cell lymphomas (ALCLs) are characterized by the expression of CD30, spontaneous regression of skin lesions, and increased concentration of CD30 ligand (CD30L). We hypothesize that CD30-CD30L interactions explain the unusual clinical behavior of cutaneous ALCLs. EXPERIMENTAL DESIGN: Eight lymphoma cell lines established from four different patients were analyzed for T-cell clonality using PCR and subsequently denaturating gradient gel electrophoresis. The expression levels of CD30 were assessed by flow cytometry. Secreted cytokines [IFN-gamma, interleukin (IL)-2, IL-4, IL-6, IL-8, and IL-10] were determined in the supernatant after 3-day culture. Proliferation and apoptosis of cultured cells were measured by 5-bromo-2-desoxyuridine and propidium iodine incorporation. RESULTS: The results showed different levels of CD30 expression and a predominant T-helper 2 profile. In a cell kinetic analysis we found that ALCL cell growth is effectively inhibited by CD30L but only in those cell lines expressing CD30 molecules in sufficient amounts on the cell surface. Cell cycle analysis revealed that growth regulation was because of apoptosis and growth arrest, and was dependent on cell culture conditions. Comparison of effects of ligation with CD30L and anti-CD30 agonistic antibody HeFi-1 revealed higher efficacy for CD30L in these ALCL lines. CONCLUSIONS: CD30+ ALCL cells can be growth inhibited by receptor ligation. Observed pleiotropic effects of CD30 signaling are most likely dependent on cell cycle status and signal strength. The binding of CD30 by its ligand provides new opportunities for controlling cell growth and treatment of CD30+ ALCL.


Assuntos
Antígeno Ki-1/biossíntese , Glicoproteínas de Membrana/metabolismo , Células Th2/metabolismo , Apoptose , Bromodesoxiuridina/farmacologia , Ligante CD30 , Ciclo Celular , Divisão Celular , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Citocinas/metabolismo , DNA/metabolismo , Citometria de Fluxo , Humanos , Cinética , Reação em Cadeia da Polimerase , Propídio/farmacologia , Ligação Proteica , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Transdução de Sinais , Fatores de Tempo
13.
Br J Haematol ; 118(4): 1019-26, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12199780

RESUMO

Sézary syndrome and Mycosis fungoides are the most common forms of cutaneous T-cell lymphomas. To assess the response to different therapies especially in Sézary syndrome, it is helpful to monitor the percentage of circulating tumour cells in the blood. The use of T-cell receptor (TCR)-Vbeta specific monoclonal antibodies provides a suitable tool for detecting Sézary cells. In this study, we analysed the levels of clonal CD4+Vbeta+ cells of seven patients with various treatment modalities using flow cytometry and investigated the immunophenotype of the clonal cells by double staining with a panel of antibodies recognizing lymphatic surface markers. Additionally, a polymerase chain reaction-denaturing gradient gel electrophoresis assay was performed on clonal CD4+Vbeta2+ cells, showing that these cells carry a Vgamma10/11, JgammaP1/2 TCR rearrangement. Follow-up studies revealed close association of the Vbeta+ clone developmentwith the clinical response to different therapiesinsixpatients. Intwo cases, the CD4+Vbeta+ cells decreased accompanied by partial regression or even complete remission. In four cases, a stable or increasing clonal CD4+Vbeta+ population reflected well a stable or progressing course of the disease. Double staining of Vbeta+ cells revealed the following pattern, CD3+, CD5+, CD7+, CD28+, CD80-, CD86+ and human leucocyte antigen (HLA) class I+. In contrast, HLA-DR was heterogeneously expressed. We conclude that identification and monitoring of CD4+Vbeta+ clonal T cells by fluorescence-activated cell sorting with double staining is a suitable method to assess clinical responses to different therapies.


Assuntos
Anticorpos Monoclonais , Linfoma Cutâneo de Células T/imunologia , Fragmentos de Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Idoso , Linfócitos T CD4-Positivos/imunologia , Feminino , Citometria de Fluxo , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Humanos , Imunofenotipagem , Contagem de Linfócitos , Linfoma Cutâneo de Células T/tratamento farmacológico , Linfoma Cutâneo de Células T/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Resultado do Tratamento
14.
Int J Cancer ; 99(1): 82-7, 2002 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11948496

RESUMO

Expression of human leucocyte antigen (HLA) Class I molecules is essential for the recognition of malignant melanoma (MM) cells by CD8(+) T lymphocytes. A complete or partial loss of HLA Class I molecules is a potent strategy for MM cells to escape from immunosurveillance. In 2 out of 55 melanoma cell cultures we identified a complete phenotypic loss of HLA allospecificities. Both patients have been treated unsuccessfully with HLA-A2 peptides. To identify the reasons underlying the loss of single HLA-A allospecificities, we searched for genomic alterations at the locus for HLA Class I alpha-chain on chromosome 6 in melanoma cell cultures established from 2 selected patients with MM in advanced stage. This deficiency was associated with alterations of HLA-A2 gene sequences as determined by polymerase chain reaction-sequence specific primers (PCR-SSP). Karyotyping revealed a chromosomal loss in Patient 1, whereas melanoma cell cultures established from Patient 2 displayed 2 copies of chromosome 6. Loss of heterozygosity (LOH) using markers located around position 6p21 was detected in both cases. By applying group-specific primer-mixes spanning the 5'-flanking region of the HLA-A2 gene locus the relevant region was amplified by PCR and subsequent sequencing allowed alignment with the known HLA Class I reference sequences. Functional assays using HLA-A2-restricted cytotoxic T-cell clones were performed in HLA-A2 deficient MM cultures and revealed a drastically reduced susceptibility to CTL lysis in HLA-A2 negative cells. We could document the occurrence of selective HLA-A2 deficiencies in cultured advanced-stage melanoma metastases and identify their molecular causes as genomic alterations within the HLA-A gene locus.


Assuntos
Antígenos de Neoplasias/genética , Antígeno HLA-A2/genética , Perda de Heterozigosidade , Melanoma/genética , Neoplasias Cutâneas/genética , Alelos , Cromossomos Humanos Par 6/genética , Citometria de Fluxo , Genes MHC Classe I/genética , Humanos , Cariotipagem , Melanoma/imunologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA , Neoplasias Cutâneas/imunologia , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas
15.
J Invest Dermatol ; 118(3): 505-12, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11874491

RESUMO

Recent clinical studies have shown the promise of bcl-2 antisense therapy in patients with melanoma. To further demonstrate the importance of bcl-2 and validate the related antiapoptotic protein bcl-xL as targets for antisense therapy in melanoma, their implication as survival factors in melanoma cells of different clinical stages as well as in normal melanocytes was investigated. Primary cell cultures derived from 17 melanomas, the cell line A375, and normal melanocytes from healthy donors were treated with antisense oligonucleotides targeting either the bcl-xL mRNA or the bcl-2 and the bcl-xL mRNAs simultaneously. Bcl-2 and bcl-xL expression in cells was analyzed by real-time polymerase chain reaction and Western blotting. Cell viability was assessed in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and apoptosis assays. Bcl-2 expression was low in melanoma cells of stages I, II, and III, hardly detectable in A375 cells, but high in normal melanocytes. Bcl-xL expression was high in all cell types tested. As shown in A375 cells and the stage III melanoma cells 0513, both the bcl-xL monospecific oligonucleotide 4259 and the bcl-2/bcl-xL bispecific oligonucleotide 4625 effectively reduced tumor cell viability by induction of apoptosis with IC50 values ranging from 200 to 350 nM. Oligonucleotide 4625 proved to be superior to 4259, as it significantly reduced the viability of cells from all melanoma stages. Both oligonucleotides reduced also the viability of normal melanocytes. Our data suggest that bcl-2 and bcl-xL are promising targets for antisense therapy of melanoma, and that the simultaneous downregulation of their expression may provide additional clinical benefit.


Assuntos
Apoptose , Genes bcl-2/genética , Melanoma/fisiopatologia , Oligonucleotídeos Antissenso/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Apoptose/fisiologia , Divisão Celular/fisiologia , Sobrevivência Celular/fisiologia , Regulação para Baixo/fisiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Melanócitos/metabolismo , Melanoma/patologia , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Valores de Referência , Células Tumorais Cultivadas , Proteína bcl-X
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