RESUMEN
BACKGROUND: The parallel ridge pattern (PRP) is considered the dermoscopic hallmark of acral melanoma (AM). However, it was recently shown that approximately one-third of AMs do not display a PRP dermoscopically, rendering their detection more troublesome. OBJECTIVES: To investigate the diagnostic accuracy of dermoscopic criteria for the diagnosis of AM. METHODS: Dermoscopic images of consecutive cases of histopathologically diagnosed AMs and acral naevi with histopathological diagnosis or with at least 1 year of follow-up were evaluated by three independent investigators for the presence of predefined criteria. Crude and adjusted odds ratios and their corresponding 95% confidence intervals were calculated by univariate and multivariate logistic regression, respectively. Receiver operating characteristic curves were used to choose among competing classification schemes. RESULTS: In total 603 lesions (472 naevi and 131 AMs) were included in the study. A scoring system (named BRAAFF) composed of six variables was associated with optimal area under the curve and sensitivity for the diagnosis of AM. This method includes four positive (irregular blotches, ridge pattern, asymmetry of structures and asymmetry of colours) and two negative predictors (furrow pattern and fibrillar pattern). CONCLUSIONS: The BRAAFF checklist significantly improves the diagnostic accuracy of dermoscopy for the diagnosis of AM.
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Algoritmos , Lista de Verificación , Dermoscopía/métodos , Melanoma/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: The morphology of pigmented skin lesions (PSLs) is predominantly a result of varying concentrations and distributions of pigmented molecules such as melanin and hemoglobin. Based on these differences and the fact that their information is contained in cutaneous spectra, a hyperspectral imager (HSI) for pigmented melanoma and a single discrimination index derived from the resultant hyperspectral data are proposed. OBJECTIVE: To develop and evaluate a new discrimination index for melanomas, compared to the previous index. METHODS: A HSI, which is convenient for both patients and clinicians, was newly developed and used in a clinical trial conducted in 2 centers with 80 patients with primary lesions and 17 volunteers between March 2011 and December 2013. There were 24 melanomas and 110 other PSLs. A previously proposed discrimination index was used without modifications. A new index, which emphasized the essential features of melanoma, was proposed, and its performance was examined. For each index, a threshold value was set to minimize the average value of the false positive and false negative fractions. The performances of both indices were compared. RESULTS: The sensitivity and specificity of the old index were 75% and 97%, respectively, while those of the new index were 96% and 87%. CONCLUSION: The new index had a higher sensitivity and adequate specificity, indicating that it is more useful than the old index.
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Algoritmos , Dermoscopía/métodos , Interpretación de Imagen Asistida por Computador/métodos , Melanoma/diagnóstico , Neoplasias Cutáneas/diagnóstico , Análisis Espectral/métodos , Adulto , Anciano , Anciano de 80 o más Años , Dermoscopía/instrumentación , Análisis Discriminante , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/instrumentación , Japón , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis Espectral/instrumentación , Adulto JovenRESUMEN
Definite diagnosis of inflammatory demyelinating disease (multiple sclerosis (MS) and neuromyelitis optica (NMO)) may require time, but early treatment offers the opportunity to maximize patient outcomes. The purpose of this report is to provide guidance to facilitate early treatment decisions for patients with inflammatory demyelinating disease, before definitive diagnosis. Neurology experts reviewed the existing literature and clinical evidence. A treatment decision pathway was developed, defining patients for whom first-line MS disease-modifying therapies (a) are unlikely to be effective, (b) may be effective but require careful monitoring and (c) are likely to provide benefit. This algorithm seeks to ensure that patients, particularly those in Asia, receive appropriate treatment early in inflammatory demyelinating disease.
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Algoritmos , Esclerosis Múltiple/terapia , Neuromielitis Óptica/terapia , Prevención Secundaria/métodos , HumanosRESUMEN
BACKGROUND: Most studies on dermoscopy of acral lesions were conducted in Asian populations. In this study, we analyzed these features in a predominantly Caucasian population. OBJECTIVE: Estimate the prevalence of dermoscopic features in acral lesions, and assess their level of agreement between observers. METHODS: In this retrospective multicenter study, 167 acral lesions (66 melanomas) were evaluated for 13 dermoscopic patterns by 26 physicians, via a secured Internet platform. RESULTS: Parallel furrow pattern, bizarre pattern, and diffuse pigmentation with variable shades of brown had the highest prevalence. The agreement for lesion patterns between physicians was variable. Agreement was dependent on the level of diagnostic difficulty. CONCLUSION: Lesions with a diameter >1 cm were more likely to be melanoma. We found as well that a benign pattern can be seen in parts of melanomas. For this reason one should evaluate an acral lesion for the presence of malignant patterns first.
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Dermoscopía , Melanoma/patología , Variaciones Dependientes del Observador , Neoplasias Cutáneas/patología , Actitud del Personal de Salud , Biopsia , Humanos , Internet , Estudios Retrospectivos , Sociedades Médicas , Población BlancaRESUMEN
BACKGROUND: Many research groups have recently developed equipments and statistical methods enabling pattern classification of pigmented skin lesions. To differentiate between benign and malignant ones, the mathematical extraction of digital patterns together with the use of appropriate statistical approaches is a challenging task. OBJECTIVE: To design a simple scoring model that provides accurate classification of benign and malignant palmo-plantar pigmented skin lesions, by evaluation of parameters obtained by digital dermoscopy analysis (DDA). PATIENTS AND METHODS: In the present study we used a digital dermoscopy analyser to evaluate a series of 445 palmo-plantar melanocytic skin lesion images (25 melanomas 420 nevi). Area under the receiver operator curve, sensitivity and specificity were calculated to evaluate the diagnostic performance of our scoring model for the differentiation of benign and malignant palmo-plantar melanocytic lesions. RESULTS: Model performance reached a very high value (0.983). The DDA parameters selected by the model that proved statistically significant were: area, peripheral dark regions, total imbalance of colours, entropy, dark area and red and blue multicomponent. When all seven model variables were used in a multivariate mode, setting sensitivity at 100% to avoid false negatives, we estimated a minimum specificity of about 80%. CONCLUSIONS: Simplicity of use and effectiveness of implementation are important requirements for the success of quantitative methods in routine clinical practice. Scoring systems meet these requirements. Their outcomes are accessible in real time without the use of any data processing system, thus allowing decisions to be made quickly and effectively.
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Dermoscopía/métodos , Pie , Mano , Trastornos de la Pigmentación/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Pigmentación/clasificaciónRESUMEN
BACKGROUND: The availability of molecular-targeted therapies for the treatment of melanoma has emphasised the need to identify mutations in target genes such as BRAF and KIT. Circulating tumour cells (CTC) are present in the peripheral blood of a significant proportion of cancer patients. METHODS: High molecular weight melanoma-associated antigen (HMW-MAA) was used to isolate melanoma cells from peripheral blood as it is selectively expressed at high levels on melanomas. The HMW-MAA-positive cells were isolated using immunomagnetic beads. After removing CD45(+) cells, CTC were identified by staining with MART-1- and gp100-specific antibodies (HMW-MAA(+), CD45(-), MART-1/gp100(+)). Single, isolated CTC were then subjected to BRAF and KIT mutational analysis. RESULTS: CTC (HMW-MAA(+), CD45(-), MART-1/gp100(+)) were isolated from the blood of 11 patients and BRAF and KIT were sequenced in nine and four patients, respectively. The BRAF sequences identified in the CTC were inconsistent with those identified in autologous melanoma tumours in three patients and the KIT sequences were inconsistent in three patients. In addition, polyclonal BRAF mutations were identified in one patient and concomitant mutations in BRAF and KIT were identified in another patient. CONCLUSION: Melanoma cells show clonal heterogeneity. Therefore, CTC genotyping may be crucial for successful molecular-targeted therapy.
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Melanoma/genética , Melanoma/patología , Células Neoplásicas Circulantes , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-kit/genética , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales , Antígenos de Neoplasias/sangre , Secuencia de Bases , Línea Celular Tumoral , Separación Celular , Análisis Mutacional de ADN , Femenino , Genes ras , Genotipo , Humanos , Separación Inmunomagnética , Antígeno MART-1/sangre , Antígeno MART-1/inmunología , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Mutación , Proteínas de Neoplasias/genética , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patología , Proteínas Proto-Oncogénicas B-raf/sangre , Análisis de Secuencia de ADN , Análisis de la Célula Individual , Neoplasias Cutáneas/genéticaRESUMEN
BACKGROUND: Fingolimod (FTY720) has previously shown clinical efficacy in phase II/III studies of predominantly Caucasian populations with multiple sclerosis (MS). OBJECTIVES: To report six-month efficacy and safety outcomes in Japanese patients with relapsing MS treated with fingolimod. METHODS: In this double-blind, parallel-group, phase II study, 171 Japanese patients with relapsing MS were randomized to receive once-daily fingolimod 0.5 mg or 1.25 mg, or matching placebo for six months. The primary and secondary endpoints were the percentages of patients free from gadolinium (Gd)-enhanced lesions at months 3 and 6, and relapses over six months, respectively; safety outcomes were also assessed. RESULTS: 147 patients completed the study. Higher proportions of patients were free from Gd-enhanced lesions at months 3 and 6 with fingolimod (0.5 mg: 70%, p = 0.004; 1.25 mg: 86%, p < 0.001) than with placebo (40%). Odds ratios for the proportions of relapse-free patients over six months favoured fingolimod versus placebo but were not significant. Adverse events related to fingolimod included transient bradycardia and atrioventricular block at treatment initiation, and elevated liver enzyme levels. CONCLUSIONS: This study demonstrated the clinical efficacy of fingolimod for the first time in Japanese patients with MS, consistent with the established effects of fingolimod in Caucasian patients.
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Inmunosupresores/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Glicoles de Propileno/uso terapéutico , Esfingosina/análogos & derivados , Adolescente , Adulto , Pueblo Asiatico , Método Doble Ciego , Esquema de Medicación , Femenino , Clorhidrato de Fingolimod , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Japón/epidemiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Esclerosis Múltiple Recurrente-Remitente/etnología , Oportunidad Relativa , Glicoles de Propileno/administración & dosificación , Glicoles de Propileno/efectos adversos , Recurrencia , Esfingosina/administración & dosificación , Esfingosina/efectos adversos , Esfingosina/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND/AIM: The diagnosis of palmoplantar melanoma is often delayed and misdiagnosis is common, due to frequently unusual clinical presentation. We used a digital dermoscopy analyzer with a series of palmoplantar pigmented skin lesions (PP-PSL), and we compared sensitivity, specificity and diagnostic accuracy obtained with digital dermoscopy analysis (DDA) and classical dermoscopy. METHODS: Digital dermoscopy images of 107 PP-PSL were retrospectively obtained from the database of images of 3 Italian centers. The lesions (25 melanomas and 82 nevi) were all removed because of the presence of clinical and/or dermoscopic suspicious features. All digital images were analyzed using appropriate algorithms, and the diagnostic accuracy of the model was calculated. For comparison, dermoscopic images were clinically evaluated by two dermatologists and the Cohen ĸ concordance with DDA was calculated. RESULTS: The stepwise logistic regression analysis selected only 5 parameters out of 49. The logistic model achieved a sensitivity of 96% and a specificity of 87.8%. The Cohen ĸ concordance, evaluated by the Landis and Koch scale, supplied a substantial agreement between dermoscopy and DDA. CONCLUSIONS: DDA might be a useful diagnostic instrument in the evaluation of preselected PP-PSL. However, these findings should be confirmed in a formal clinical trial.
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Melanoma/diagnóstico , Nevo/diagnóstico , Trastornos de la Pigmentación/diagnóstico , Neoplasias Cutáneas/diagnóstico , Población Blanca , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Dermoscopía/métodos , Diagnóstico Diferencial , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Nevo/etnología , Trastornos de la Pigmentación/etnología , Estudios Retrospectivos , Neoplasias Cutáneas/etnología , Adulto JovenRESUMEN
BACKGROUND: Oncogenic BRAF mutation had been considered to be a founder event in the formation of melanocytic tumours; however, we recently argued against this notion by showing marked polyclonality of BRAF mutations in acquired melanocytic nevi (Lin et al, J Natl Cancer Inst., 2009; 101:1423-7). Here, we tested whether similar heterogeneity of BRAF mutations exists in primary melanomas. METHODS: We isolated and sequenced single melanoma cells from five primary melanoma tissues using antibodies against human high-molecular-weight melanoma-associated antigen. We also examined 10 primary melanomas by the sensitive Mutector assay detecting the BRAF(V600E) mutation, as well as by cloning and sequencing of separated alleles. Furthermore, we estimated the frequency of BRAF mutant alleles in paired samples of primary tumour and recurrence or metastasis in three patients. RESULTS: Single-cell mutation analyses revealed that four of five primary melanomas contained both BRAF-wild-type and BRAF-mutant tumour cells. Tumour heterogeneity in terms of BRAF mutations was also shown in 8 of 10 primary melanomas. Selection of BRAF mutant alleles during progression was demonstrated in all the three patients. CONCLUSION: Acquisition of a BRAF mutation is not a founder event, but may be one of the multiple clonal events in melanoma development, which is selected for during the progression.
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Proteínas Proto-Oncogénicas B-raf/genética , Alelos , Línea Celular Tumoral , Células Clonales , Humanos , Melanoma/genética , Mutación , Neoplasias Cutáneas/genéticaRESUMEN
BACKGROUND: The dermoscopic features of pigmented lesions on the mucocutaneous junction and mucous membrane are different from those on hairy skin. Differentiation between benign lesions and malignant melanomas of these sites is often difficult. OBJECTIVE: To define the dermoscopic patterns of lesions on the mucocutaneous junction and mucous membrane, and assess the applicability of standard dermoscopic algorithms to these lesions. PATIENTS AND METHODS: An unselected consecutive series of 40 lesions on the mucocutaneous junction and mucous membrane was studied. All the lesions were imaged using dermoscopy devices, analysed for dermoscopic patterns and scored with algorithms including the ABCD rule, Menzies method, 7-point checklist, 3-point checklist and the CASH algorithm. RESULTS: Benign pigmented lesions of the mucocutaneous junction and mucous membrane frequently presented a dotted-globular pattern (25%), a homogeneous pattern (25%), a fish scale-like pattern (18.8%) and a hyphal pattern (18.8%), while melanomas of these sites showed a multicomponent pattern (75%) and a homogeneous pattern (25%). The fish scale-like pattern and hyphal pattern were considered to be variants of the ring-like pattern. The sensitivities of the ABCD rule, Menzies method, 7-point checklist, 3-point checklist and CASH algorithm in diagnosing mucosal melanomas were 100%, 100%, 63%, 88% and 100%; and the specificities were 100%, 94%, 100%, 94% and 100%, respectively. CONCLUSION: The ring-like pattern and its variants (fish scale-like pattern and hyphal pattern) are frequently observed as well as the dotted-globular pattern and homogeneous pattern in mucosal melanotic macules. The algorithms for pigmented lesions on hairy skin also apply to those on the mucocutaneous junction and mucous membrane with high sensitivity and specificity.
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Dermoscopía/métodos , Melanoma/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Competencia Clínica , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/patología , Estadificación de Neoplasias , Variaciones Dependientes del Observador , Guías de Práctica Clínica como Asunto , Adulto JovenRESUMEN
Thirteen of 31 rabbits immunized repeatedly with bovine brain galactocerebroside developed experimental allergic neuritis, manifested by flaccid paresis and hypesthesia of four limbs, 2 to 11 months after the initial inoculation. Electrophysiological studies revealed multifocal conduction block of peripheral nerves. Perivenular demyelinative lesions associated with phagocytic mononuclear cells occurred in spinal ganglia, roots, and less frequently in distal nerves.
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Enfermedades Autoinmunes/inmunología , Cerebrósidos/inmunología , Enfermedades Desmielinizantes/inmunología , Galactosilceramidas/inmunología , Neuritis/inmunología , Animales , Autoanticuerpos/análisis , Enfermedades Desmielinizantes/patología , Masculino , Vaina de Mielina/fisiopatología , Conducción Nerviosa , Neuritis/patología , Neuritis/fisiopatología , ConejosRESUMEN
A novel benzophenone derivative, 2-(2-benzoyl-4-chlorophenoxy)-N-methylpropionamide (Ch-13), induced phenotypic differentiation linked to the inhibition of cell proliferation in human thymic acute lymphoblastic leukemia cell line HPB-ALL cells. The Ch-13-induced morphological changes consist of a decrease in cell size, nucleolar disappearance, and an alteration in the chromatin distribution, resembling large or atypical lymphocytes. Treatment with Ch-13 brought about a remarkable reduction in OKT6-, OKT4/Leu3a-, and OKT9-positive cells. At the optimal differentiation-inducing dose (5 X 10(-5)M), Ch-13 inhibited the cell proliferation, de novo DNA synthesis, and specific antibody-induced cell surface antigen capping.
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Benzofenonas/toxicidad , Leucemia Linfoide/patología , Neoplasias del Timo/patología , Antígenos de Superficie/análisis , División Celular/efectos de los fármacos , Línea Celular , Humanos , Cinética , Fenotipo , Relación Estructura-ActividadRESUMEN
12-O-Tetradecanoylphorbol-13-acetate (TPA), a potent tumor promoter, induced phenotypic differentiation in the human thymic acute lymphocytic leukemia cell line, HPB-ALL. Within 30 min of seeding in the presence of TPA, the cells formed a smooth round shape. After a 7-day exposure to TPA, most of the cells became smaller and reminiscent of large or atypical lymphocytes. Electron microscopic analysis evidenced morphological differentiation in TPA-treated HPB-ALL cells. Thymic antigens stained with monoclonal antibody OKT6 were dramatically reduced while Leu2a-positive cells were increased in the TPA-treated HPB-ALL cells. However, OKT3-positive cells did not appear in these TPA-treated cells for up to 7 days. Upon TPA-induced phenotypic differentiation, the growth rate of cells was significantly inhibited, their ability to incorporate DNA and RNA via 3H-labeled precursors was reduced, their ability to bind sheep red blood cell rosettes was significantly increased, and the proportion of terminal deoxynucleotidyl transferase-positive cells was decreased.
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Forboles/farmacología , Linfocitos T/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología , Antígenos de Superficie , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , ADN/biosíntesis , ADN Nucleotidilexotransferasa/metabolismo , Humanos , Leucemia Linfoide , Masculino , ARN/biosíntesis , Formación de Roseta , Linfocitos T/inmunología , Linfocitos T/fisiologíaRESUMEN
Serological identification of tumor antigens by cDNA expression cloning is a technique used to isolate cDNAs encoding tumor antigens that are recognized by IgG antibodies in sera from cancer patients. It is also useful for the isolation of tumor antigens recognized by T cells. We applied this method to identify melanoma antigens recognized by the serum from a patient with a good prognosis who had T-cell-infiltrated melanoma and vitiligo. By screening a lambda phage cDNA library constructed from a highly pigmented melanoma cell line, SKmel23, with the patient's serum, 50 positive cDNA clones consisting of 26 distinct antigens were isolated. Of these, 20 encoded known proteins, and 6 encoded previously uncharacterized ones. The most frequently isolated clone, which we named KU-MEL-1, was unknown previously but was homologous to partial cDNA sequences registered in the expressed sequence tag database. Reverse transcription-PCR and Northern blot analysis demonstrated that KU-MEL-1 was strongly expressed in most melanoma cell lines, melanoma tissue samples, and cultured melanocytes and weakly expressed in cell lines derived from other types of tumors, as well as in some normal tissues, including testis. Western blot analysis with polyclonal murine antibody generated by immunization with the recombinant KU-MEL-1 protein demonstrated that the KU-MEL-1 protein was preferentially expressed in melanoma cells and melanocytes. IgG antibodies against KU-MEL-1 were detected in the sera from 9 of 26 melanoma patients and from some patients with other cancers, including brain tumor, esophageal cancer, colon cancer, and chronic myelogenous leukemia, but were not detected in sera from 30 healthy individuals. Although the IgG specific for KU-MEL-1 was not detected in sera from 12 vitiligo patients, it was detected in sera from 7 of 11 patients with Vogt-Koyanagi-Harada disease that is thought to be an autoimmune disease against melanocytes. These results suggest that KU-MEL-1 may be a useful target for the development of diagnostic and therapeutic methods for patients with various cancers, particularly with melanoma, as well as patients with autoimmune diseases against melanocytes.
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Antígenos de Neoplasias/aislamiento & purificación , Linfocitos Infiltrantes de Tumor/inmunología , Melanoma/inmunología , Linfocitos T/inmunología , Vitíligo/inmunología , Anciano , Anciano de 80 o más Años , Secuencia de Aminoácidos , Especificidad de Anticuerpos , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Secuencia de Bases , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Femenino , Humanos , Inmunoglobulina G/inmunología , Melanocitos/inmunología , Melanoma/química , Melanoma/complicaciones , Datos de Secuencia Molecular , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Pruebas Serológicas , Vitíligo/complicacionesRESUMEN
It is well known that tumor-specific CTLs have a crucial role in the elimination of tumors and that different CTL populations recognize tumor antigens in MHC-restricted and MHC-unrestricted manners. We have established two alpha beta CTL clones that recognize melanoma antigens in both human lymphocyte antigen (HLA)-A2-restricted and HLA-unrestricted manners. Flow cytometry analysis showed that these CTL clones carry CD3, CD8, and alpha beta T-cell receptor (TCR) and express low levels of CD56. In contrast, these CTL clones do not express CD16, indicating that they do not contain natural killer cells. TCR analysis of these CTL clones using an anchored PCR method revealed that each clone carries a single alpha beta TCR. Both CTL clones contained the same Valpha and Vbeta gene segments although they carried different Jalpha and Jbeta gene segments. Taken together, these results confirm that CTL clones that carry a single alpha beta TCR recognize melanoma antigens in both HLA-A2-restricted and HLA-unrestricted manners. It is strongly suggested that the dual recognition of these CTL clones for the melanoma antigens is mediated by TCRs. The novel mechanism for antitumor immunity by these CTLs may be important in the effective elimination of tumors in vivo.
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Antígeno HLA-A2/inmunología , Melanoma/inmunología , Proteínas de Neoplasias/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Proteínas Recombinantes de Fusión/inmunología , Linfocitos T Citotóxicos/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Presentación de Antígeno , Antígenos de Neoplasias , Secuencia de Bases , Citotoxicidad Inmunológica , Reordenamiento Génico de Linfocito T , Antígeno HLA-A2/genética , Humanos , Activación de Linfocitos , Antígenos Específicos del Melanoma , Datos de Secuencia Molecular , Neoplasias/inmunología , Neoplasias/patología , Reacción en Cadena de la Polimerasa , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Transfección , Células Tumorales CultivadasRESUMEN
Hyaluronate plays a unique role in the cancer cell microenvironment. In particular, melanoma is the tumor type in which hyaluronate and hyaluronate recognition have been most closely linked to malignancy. In this study we show that a human melanoma cell line stably transfected with hyaluronate synthase cDNA displays enhanced motility. We used a fixed erythrocyte exclusion assay to isolate subsets of the WM793 human melanoma cell line that expressed either high or low amounts of hyaluronate. A cell line with a high level of hyaluronate on its surface (WM793H) displayed significantly higher cell motility on colloidal-gold-coated coverslips than did a line with a low level (WM793L). Next, in order to directly investigate the effects of hyaluronate on melanoma cell migration, we transfected cDNA encoding mouse hyaluronate synthase HAS1 or HAS2 into the re-cloned human melanoma cell line that produced a low amount of hyaluronate (WM793L) by the lipofection method. Several clonal transfectants differentially producing hyaluronate were obtained. There was a positive correlation between total hyaluronate synthesis and formation of the pericellular hyaluronate-rich matrix. We observed an increase in the migration ability of hyaluronate cDNA (HAS1 or HAS2)-transfected cells compared with control cells on glass plates covered with colloidal gold particles. A migration-inhibition assay with anti-CD44 monoclonal antibody showed blocking of the cell motility. It is speculated that the tumor cells might migrate through a hyaluronate-rich extracellular environment when they invade nearby host tissues and that hyaluronate production by the tumor cells could increase this migration. These results suggest that hyaluronate may play a role in the aggressiveness of human melanoma cells.
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Glicosiltransferasas , Ácido Hialurónico/fisiología , Melanoma/patología , Proteínas de la Membrana , Transferasas , Proteínas de Xenopus , Animales , Anticuerpos Monoclonales/uso terapéutico , Movimiento Celular , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/fisiología , Humanos , Receptores de Hialuranos/fisiología , Hialuronano Sintasas , Ratones , Transfección , Células Tumorales CultivadasRESUMEN
The nature and expression pattern of the 97 kDa linear IgA bullous dermatosis antigen (LAD-1) and its role in epidermolysis bullosa have not been fully elucidated. In this study, we examined the expression of LAD-1 in the skin specimens of 70 patients with the various subtypes of epidermolysis bullosa, including simplex (n = 23), junctional (n = 15), and dystrophic variants (n = 32). For immunolabeling, we used two recently developed monoclonal antibodies to LAD-1 whose epitopes were ultrastructurally localized in the lamina lucida between NC16A and carboxyterminal domains of BPAG2, as well as autoantibodies against LAD-1 from the sera of two patients with linear IgA dermatosis. Among the 70 patients, only one patient with generalized atrophic benign epidermolysis bullosa failed to demonstrate LAD-1 expression. Although other major basement membrane components, including laminin 5, BPAG1, plectin, alpha6 and beta4 integrins, as well as type IV and type VII collagens were normally expressed, BPAG2/type XVII collagen was absent from the skin of this patient. Mutation analysis on COL17A1 using polymerase chain reaction amplification, heteroduplex scanning, and direct nucleotide sequencing revealed that this patient was homozygous for a novel nonsense mutation G258X in exon 11, and her parents were heterozygous carriers for this mutation. This is the first mutation located in the intracellular domain of BPAG2, and resides 817 bp upstream from the N-terminal amino acid sequence of LAD-1. These findings indicate that the absent expression of LAD-1 is observed in a BPAG2-deficient generalized atrophic benign epidermolysis bullosa patient with mutations in both alleles of COL17A1, and not in other epidermolysis bullosa subtypes. These findings also support the notion that LAD-1 is a degradation product of BPAG2.
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Proteínas Portadoras , Colágeno/genética , Proteínas del Citoesqueleto , Epidermólisis Ampollosa Distrófica/genética , Proteínas del Tejido Nervioso , Colágenos no Fibrilares , Enfermedades Cutáneas Vesiculoampollosas/inmunología , Antígenos/genética , Autoantígenos/análisis , Autoantígenos/genética , Estudios de Cohortes , Desmosomas/metabolismo , Distonina , Epítopos/análisis , Femenino , Análisis Heterodúplex , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Mutación , Piel/química , Colágeno Tipo XVIIRESUMEN
Although human T-lymphotropic virus type I (HTLV-I) has been implicated in the etiology of tropical spastic paraparesis (TSP) and HTLV-I associated myelopathy (HAM), the direct infectivity of the virus against constituent cells in the central nervous system remains undetermined. To investigate the neurotropism of HTLV-I, we exposed cultured human and simian glial cells to HTLV-I. Primary mixed glial cell cultures of astrocytes and oligodendrocytes were obtained from adult human and cynomolgus monkey (Macaca fascicularis) brains by an enzyme digestion-Percoll gradient method. After two weeks in vitro, the cells were co-cultured with irradiated MT-2 cells, an HTLV-I-producing T-cell line. Cultures were double stained with antibodies against cell-type specific markers and anti-HTLV-I p19 (gag) monoclonal antibody. The HTLV-I antigen was demonstrated in small numbers of glial fibrillary acidic protein-positive cells (astrocytes) and galactocerebroside-positive cells (oligodendrocytes) in both the human and simian cultures. Electron microscopy demonstrated the presence of type C virus-like particles in the cytoplasm of astrocytes. These results indicate that HTLV-I is capable of infecting human and simian glial cells in vitro.
Asunto(s)
Virus Linfotrópico T Tipo 1 Humano/crecimiento & desarrollo , Neuroglía/microbiología , Adulto , Animales , Astrocitos/microbiología , Astrocitos/ultraestructura , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Proteína Ácida Fibrilar de la Glía/análisis , Humanos , Macaca fascicularis , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Neuroglía/ultraestructura , Oligodendroglía/microbiología , Oligodendroglía/ultraestructuraRESUMEN
Intraneural injection of sera from rabbits with experimental allergic encephalomyelitis, induced by sensitization with bovine brain white matter in complete Freund's adjuvant, produced focal primary demyelinative lesions in rat sciatic nerves. Demyelinating activity was removed by prior incubation of antisera with central (CNS) and peripheral nervous system (PNS) myelin but not with liver or kidney, and was heat-labile and complement-dependent. Recipient animals developed a sensorimotor disturbance of their toes and ankles on the side injected with antiserum. Twenty minutes after antiserum injection, Schwann cells showed focal cytoplasmic outpouching and their external mesaxons opened. Between 1 and 8 hours after injection vacuolation, splitting and vesiculation of myelin became increasingly prominent at Schmidt-Lanterman clefts and paranodal regions, with concomitant degenerative changes in Schwann cell cytoplasm. Polymorphonuclear cell infiltration and endoneurial edema were apparent at this time. Substantial demyelination occurred before the appearance of phagocytic cells. Between 8 hours and 3 days many nerve fibers were surrounded and attacked by invading macrophages. Axons became demyelinated progressively over several internodes by macrophage phagocytosis. Early signs of remyelination were observed by 5 days. These findings suggest that antibodies directed against antigens common to both CNS and PNS myelin can produce in vivo peripheral nerve demyelination.