RESUMO
Patients with advanced Ewing sarcoma (AES) carry a poor prognosis. Retrospectively, we analyzed 66 AES patients treated with allogeneic stem cell transplantation (allo-SCT) receiving HLA-mismatched (group A, n = 39) versus HLA-matched grafts (group B, n = 27). Median age at diagnosis was 13 years, and 15 years (range 3-49 years) at allo-SCT. The two groups did not differ statistically in distribution of gender, age, remission status/number of relapses at allo-SCT, or risk stratum. 9/39 (23%) group A versus 2/27 (7%) group B patients developed severe acute graft versus host disease (GvHD). Of patients alive at day 100, 7/34 (21%) group A versus 9/19 (47%) group B patients had developed chronic GvHD. In group A, 33/39 (85%) versus 20/27 (74%) group B patients died of disease and 1/39 (3%) versus 1/27 (4%) patients died of complications, respectively. Altogether 12/66 (18%) patients survived in CR. Median EFS 24 months after allo-SCT was 20% in both groups, median OS was 27% (group A) versus 17% (group B), respectively. There was no difference in EFS and OS in AES patients transplanted with HLA-mismatched versus HLA-matched graft in univariate and multivariate analyses. In this analysis, CR at allo-SCT is a condition for survival (p < 0.02).
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Sarcoma de Ewing , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Sarcoma de Ewing/terapia , Condicionamento Pré-Transplante , Adulto JovemRESUMO
During T cell development, thymocytes which are tolerant to self-peptides but reactive to foreign peptides are selected. The current model for thymocyte selection proposes that self-peptide-major histocompatibility complex (MHC) complexes that bind the T cell receptor with low affinity will promote positive selection while those with high affinity will result in negative selection. Upon thymocyte maturation, such low affinity self-peptide-MHC ligands no longer provoke a response, but foreign peptides can incidentally be high affinity ligands and can therefore stimulate T cells. For this model to work, thymocytes must be more sensitive to ligand than mature T cells. Contrary to this expectation, several groups have shown that thymocytes are less responsive than mature T cells to anti-T cell receptor for antigen (TCR)/CD3 mAb stimulation. Additionally, the lower TCR levels on thymocytes, compared with T cells, would potentially correlate with decreased thymocyte sensitivity. Here we compared preselection thymocytes and mature T cells for early activation events in response to peptide-MHC ligands. Remarkably, the preselection thymocytes were more responsive than mature T cells when stimulated with low affinity peptide variants, while both populations responded equally well to the antigenic peptide. This directly demonstrates the increased sensitivity of thymocytes compared with T cells for TCR engagement by peptide-MHC complexes.
Assuntos
Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Timo/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Cálcio/metabolismo , Regulação para Baixo/imunologia , Citometria de Fluxo , Camundongos , Camundongos Transgênicos , Ovalbumina/imunologia , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Timo/citologia , Regulação para Cima/imunologiaRESUMO
BACKGROUND: Vitamin E is an antioxidant that inhibits mutagenesis and cell transformation. Previous findings in five prospective epidemiologic studies suggested that the level of serum alpha-tocopherol, the predominant form of vitamin E in the blood, was lower in subjects who subsequently developed colorectal cancer than in control subjects. However, the difference was neither obvious nor statistically significant in any one of these five studies. PURPOSE: To evaluate in greater detail the association between serum alpha-tocopherol concentration and risk of colorectal cancer, we pooled and analyzed the original data from the five studies. Our analyses were designed to (a) test the hypothesis with greater statistical power, (b) examine the association after adjustment for serum cholesterol levels, and (c) evaluate the association after uniform exclusion of cases diagnosed shortly after blood specimens were drawn. METHODS: Data for individual subjects were analyzed. To make the design of the component investigations uniformly nested case-control studies with individual matching, we matched controls to cases in two of the cohorts. Subjects were categorized according to study-specific quartile of serum alpha-tocopherol level within the study. The pooled analysis included 289 cases of colorectal cancer and 1267 matched controls. RESULTS: For cancers of the colon and rectum combined, the matched odds ratio (OR) for the highest quartile of serum alpha-tocopherol concentration compared with the lowest was 0.6 (95% confidence interval [CI] = 0.4-1.0). Adjustment for serum cholesterol level attenuated the OR to 0.7 (95% CI = 0.4-1.1). CONCLUSION: The results suggest that serum alpha-tocopherol concentration may be inversely related to risk of colorectal cancer. It is unclear whether an association exists, however, because the association between serum alpha-tocopherol level and decreased risk of colorectal cancer was modest, the CIs were wide, and, overall, the tests for trend in effect were not significant. IMPLICATIONS: Larger observational studies with concurrent dietary data are needed to determine whether vitamin E has a modest but potentially important protective effect against colorectal cancer.
Assuntos
Neoplasias Colorretais/sangue , Vitamina E/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
BACKGROUND: Mercury amalgam dental restorations have been used by dentists since the mid 19th century and issues on safety continue to be periodically debated within the scientific and public health communities. Previous studies have reported a positive association between urine mercury levels and the number of dental amalgams, but this relation has never been described in a nationally representative sample in the United States. AIMS AND METHODS: Using household interview, dietary interview, dental examination, and laboratory data from the 1999-2000 National Health and Nutrition Examination Survey (NHANES), the association between mercury concentrations and dental restorations was examined in US women of reproductive age. RESULTS: In women of childbearing age, approximately 13% of all posterior dental surfaces were restored with amalgams and the average urinary mercury level in women was low (1.34 microg/l). It is estimated that an increase of 1.8 microg/l in the log transformed values for mercury in urine would occur for each 10 dental surfaces restored with amalgam. CONCLUSIONS: Although the findings do not address the important issues of adverse health effects at low thresholds of mercury exposure, they do provide important reference data that should contribute significantly to the ongoing scientific and public health policy debate on the use of dental amalgams in the USA.
Assuntos
Amálgama Dentário/farmacocinética , Restauração Dentária Permanente , Mercúrio/urina , Adolescente , Adulto , Restauração Dentária Permanente/estatística & dados numéricos , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Lineares , Mercúrio/sangue , Pessoa de Meia-Idade , Fumar/urinaRESUMO
Merocyanine 540 (MC 540) is a photosensitizing dye that is used clinically for the purging of autologous bone marrow grafts and preclinically for the inactivation of enveloped viruses in blood products. In this paper we present evidence that the MC 540-sensitized photoinactivation of leukemia cells is an oxygen-dependent process and that unsaturated plasma membrane lipids are substrates for singlet oxygen and/or other activated oxygen species generated by photoirradiated MC 540. A comparison of the inhibition of clonal growth, the inhibition of mitochondrial respiration, and the exclusion of trypan blue by the plasma membrane after exposure to MC 540 and graded doses of light showed that mitochondrial respiration is compromised relatively early in the course of the dye-mediated photoinactivation of cells, well before the plasma membrane loses its capacity to exclude trypan blue. It also showed that trypan blue exclusion assays can greatly underestimate the cytotoxic effects of MC 540-sensitized photoirradiation.
Assuntos
Leucemia/patologia , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Oxigênio/metabolismo , Pirimidinonas/farmacologia , Radiossensibilizantes/farmacologia , Animais , Membrana Celular/efeitos dos fármacos , Ácidos Graxos Insaturados/metabolismo , Humanos , Leucemia/metabolismo , Camundongos , Células Tumorais CultivadasRESUMO
Merocyanine 540 (MC 540) is a photosensitizing dye that has been used in a phase I clinical trial for the purging of leukemia and lymphoma cells from autologous bone marrow grafts. In this paper we examine the role of plasma membrane negative charge, plasma membrane fluidity, and plasma membrane hydrophobicity in the regulation of a cell's susceptibility to MC 540-sensitized photoirradiation. Among solid tumor cells, we found an inverse correlation between surface electronegativity, affinity for dye molecules, and susceptibility to MC 540-sensitized photoinactivation. That is, the least electronegative cells bound the highest amount of dye and were the most susceptible to dye-sensitized photoirradiation. By contrast, no such correlations were found among leukemia/lymphoma cells. This suggested that dye binding and susceptibility to MC 540-mediated photodynamic damages are regulated differently in hematopoietic/lymphopoietic and solid tumor cells.
Assuntos
Medula Óssea/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Neoplasias/tratamento farmacológico , Pirimidinonas/toxicidade , Medula Óssea/efeitos da radiação , Células da Medula Óssea , Separação Celular , Humanos , Luz , Fluidez de Membrana , Neuraminidase/farmacologia , Radiossensibilizantes , Solubilidade , Propriedades de Superfície , Tripsina/farmacologia , Células Tumorais CultivadasRESUMO
OBJECTIVE: The objective of this study was to examine age-specific population-based values for serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels in women in the U.S. population. DESIGN: Data were collected from a nationally representative cross-sectional health examination survey that included measurements of follicle-stimulating hormone and luteinizing hormone and information from a personal interview. A total of 3388 women aged 35 to 60 years were examined during the third National Health and Nutrition Examination Survey, 1988-1994. RESULTS: Among U.S. women aged 35-60 years, median FSH and LH levels began to increase for women in their late 40s and reached a plateau for women in their early 50s. This study supports the previously reported association between serum FSH and age (i.e., serum FSH and LH levels increase with age) and smoking (i.e., current smoking was associated with an increased level of serum FSH). At FSH levels of > or = 15 IU/L or > or = 20 IU/L. 70 and 73% of women, respectively, were postmenopausal. Our study also found an interaction between age and oophorectomy. In addition, the present data suggest that women with only one ovary may have higher FSH levels than women with both of their ovaries. CONCLUSIONS: NHANES III provides population-based data that support previously reported associations between serum FSH level and age, smoking, and menopausal status.
Assuntos
Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Menopausa/fisiologia , Adulto , Distribuição por Idade , Envelhecimento/fisiologia , Estudos Transversais , Terapia de Reposição de Estrogênios , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos Nutricionais , Valores de Referência , Sensibilidade e Especificidade , Estados UnidosRESUMO
Segmental muscle enlargement occurs in a variety of neurogenic conditions. We present a patient with calf hypertrophy, likely produced by continuous neuromuscular irritability and compensatory type 1 and type 2 muscle fiber hypertrophy. The underlying lesion of the S1 nerve root was caused by scarring, which could be demonstrated by Gadolinum enhanced, fat saturated magnetic resonance imaging. Thus, the application of this technique is recommended in otherwise etiologically unclear cases of neurogenic muscular lesions in order to detect chronic nerve root pathology.
Assuntos
Cicatriz/complicações , Músculos/patologia , Doenças do Sistema Nervoso Periférico/complicações , Raízes Nervosas Espinhais , Adulto , Cicatriz/diagnóstico , Meios de Contraste , Eletromiografia , Gadolínio DTPA , Humanos , Hipertrofia/etiologia , Imageamento por Ressonância Magnética , Masculino , Doenças do Sistema Nervoso Periférico/diagnóstico , Radiculopatia/complicações , Sacro , Raízes Nervosas Espinhais/patologia , Tomografia Computadorizada por Raios XRESUMO
Operators of hospital sterilizers that use ethylene oxide were studied to determine if there was a relationship between exposure and a battery of biological markers. A total of 73 workers from nine hospitals in the United States (U.S.) and one hospital in Mexico City was evaluated for ethylene oxide exposure during four months prior to collection of peripheral blood. The frequency of hemoglobin adducts (p = 0.0006) and sister-chromatid exchanges (SCEs) (p = 0.002) increased with cumulative exposure to ethylene oxide in U.S. subjects when controlling by regression analysis for various confounding factors, including cigarette smoking. Hemoglobin adducts, but not SCEs, were also increased in Mexican subjects (p = 0.0012). Chromosomal micronuclei showed no consistent relationship with exposure. The U.S. study participants were classified by four-month cumulative exposure levels of 10 ppm-h (n = 8), greater than 0 to 32 ppm-h (n = 32) and greater than 32 ppm-h (n = 11) of ethylene oxide exposure. The group with an exposure of greater than 32 ppm-h had an increased frequency of hemoglobin adducts (p = 0.002) and SCEs (p = 0.0001) compared to the nonexposed group. The estimated mean of the 8-h time-weighted average (8-h TWA) exposure levels for the highest U.S. exposure group (greater than 32 ppm-h) was 0.16 +/- 0.007 ppm (mean +/- SD). A similar exposure-related differential was observed in the Mexican subjects for hemoglobin adducts (p = 0.04) but not for SCEs. The latter finding may have been due to longer shipping times for the specimens in the cytogenetic assays. The estimated mean of the 8-h TWA exposure levels for the highest Mexican exposure group (greater than 32 ppm-h) was 0.48 +/- 0.08 ppm. This study is the third to suggest that exposures less than the U.S. OSHA standard of 1 ppm 8-h TWA result in biochemical and biologic changes. It is not known whether these changes may be indicative of increased risk of disease; however, they do appear to reflect exposure to relatively low levels of ethylene oxide. The exact meaning of these changes is unknown.
Assuntos
Óxido de Etileno/toxicidade , Exposição Ocupacional , Recursos Humanos em Hospital , Adulto , Biomarcadores , Feminino , Humanos , Masculino , México , Análise de Regressão , Troca de Cromátide Irmã , Estados UnidosRESUMO
Andreas Rett described a "cerebral atrophic syndrome accompanying hyperammonemia" for the first time in 1966, and by 1983 over 80 such cases had been identified and described not only in Austria but also in other countries. If the information at our disposal is correct, we have reported on what we believe is the first case of a patient with a definite Rett syndrome in the German Democratic Republic. We are, regrettably, still unable to contribute decisively to the clarification of the etiology and pathogenesis of the disease, but will, through further publications and papers at pediatric and child-neuropsychiatric meetings, continue to spread the knowledge of the symptomatology. It is remarkable that in the present case neither computer tomography nor electroencephalography showed definite abnormalities despite much effort. Definite proof of cerebral atrophy cannot, therefore, yet be furnished. But we still have no doubt that our diagnosis is correct. We intend, within the framework of a joint study being conducted by the University Pediatric Hospital Rostock and the Ludwig Boltzmann Institute, Vienna, as part of the scientific and technical cooperation between the Republic of Austria and the German Democratic Republic, to investigate further the epidemiology and etiology of this disease in cooperation with our Departments of Metabolic Disturbances and Genetics.
Assuntos
Deficiência Intelectual/diagnóstico , Transtornos Neurocognitivos/diagnóstico , Comportamento Estereotipado , Amônia/sangue , Atrofia , Córtex Cerebral/patologia , Desenvolvimento Infantil , Pré-Escolar , Eletroencefalografia , Feminino , Humanos , SíndromeRESUMO
To assess mortality attributed to misuse of psychoactive drugs in the United States from 1979 through 1988, the authors obtained from death certificates the annual number of, and age-, sex-, and race-specific data for, deaths in which psychoactive drugs were coded as the underlying or contributing cause. Deaths with psychoactive drugs specified as underlying cause (drug-induced) increased from 6,500 (2.9 per 100,000) in 1979 to more than 10,000 (3.8 per 100,000) in 1988. Deaths with psychoactive drugs specified as either underlying or contributing cause (drug-related) increased from 7,200 (3.2 per 100,000) in 1979 to more than 14,400 (5.5 per 100,000) in 1988. The drugs that primarily accounted for this increase were illicit, in particular, the opiates (heroin) and cocaine, with most of the remainder accounted for by misuse of various legal drugs. The largest increases between 1979 and 1988 occurred among black men ages 35-44 whose drug-induced death rates rose from 8 to 36 per 100,000 and whose drug-related death rates from 10 to 82 per 100,000. These data identify a high-risk group for targeting efforts to prevent deaths due to misuse of psychoactive drugs.
Assuntos
Drogas Ilícitas , Psicotrópicos , Transtornos Relacionados ao Uso de Substâncias/mortalidade , Adulto , Causas de Morte , Cocaína , Atestado de Óbito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Entorpecentes , Estados Unidos/epidemiologiaRESUMO
Clearly increased sIgA values were found in cystic fibrosis patients in more than 70%. The highest concentrations were seen in patients with obstructive liver disease. There were no correlations between sIgA and liver-associated enzymes. Postmortem histology and sIgA correlated well. These data suggest a pertinent role of sIgA assessment in evaluation of hepatic involvement in cystic fibrosis.
Assuntos
Fibrose Cística/imunologia , Imunoglobulina A Secretora/metabolismo , Adolescente , Adulto , Asma/imunologia , Bronquiectasia/imunologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lactente , Cirrose Hepática Biliar/imunologia , MasculinoRESUMO
T cells have been proven to be therapeutically effective in patients with relapsed leukemias, although target antigens on leukemic cells as well as T-cell receptors (TCRs), potentially recognizing those antigens, are mostly unknown. We have applied an immunopeptidomic approach and isolated human leukocyte antigen (HLA) ligands from primary leukemia cells. We identified a number of ligands derived from different genes that are restrictedly expressed in the hematopoietic system. We exemplarily selected myeloperoxidase (MPO) as a potential target and isolated a high-avidity TCR with specificity for a HLA-B*07:02-(HLA-B7)-restricted epitope of MPO in the single HLA-mismatched setting. T cells transgenic for this TCR demonstrated high peptide and antigen specificity as well as leukemia reactivity in vitro and in vivo. In contrast, no significant on- and off-target toxicity could be observed. In conclusion, we here demonstrate, exemplarily for MPO, that leukemia-derived HLA ligands can be selected for specific effector tool development to redirect T cells to be used for graft manipulation or adoptive T-cell therapies in diverse transplant settings. This approach can be extended to other HLA ligands and HLA molecules in order to provide better treatment options for this life-threatening disease.
Assuntos
Antígenos HLA/imunologia , Leucemia Mieloide/genética , Leucemia Mieloide/imunologia , Peptídeos/imunologia , Peroxidase/imunologia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Apresentação de Antígeno/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Modelos Animais de Doenças , Mapeamento de Epitopos , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Antígenos HLA/metabolismo , Antígeno HLA-B7/imunologia , Antígeno HLA-B7/metabolismo , Xenoenxertos , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/mortalidade , Ligantes , Camundongos , Peptídeos/metabolismo , Peroxidase/química , Peroxidase/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Transdução GenéticaAssuntos
Antígenos CD/fisiologia , Movimento Celular/fisiologia , Integrinas/fisiologia , Antígenos CD/genética , Técnicas de Cultura de Células/métodos , Células Cultivadas , Humanos , Integrina alfa2 , Melanoma , Microscopia de Vídeo/métodos , Proteínas Recombinantes/metabolismo , Transfecção/métodos , Células Tumorais CultivadasRESUMO
BACKGROUND: Urinary tract stones (stones) are believed to be unusually common in the southeastern United States but neither the incidence of nor the risk factors for stones are known. METHODS: In three well-defined occupational populations in eastern Tennessee, we assessed the prevalence, incidence, and cumulative incidence of stones and measured biochemical risk factors for lithogenesis. RESULTS: The age-adjusted prevalence of stones was 18.5 percent in Tennessee compared to 7.7 percent among White males in US NHANES (prevalence ratio 2.4, 95% CI 1.7, 3.3). The cumulative incidence (risk) was 27.8 percent by age 65, higher than in any other reported population. Risk factors were age, a family history, and urinary saturation with calcium-oxalate (COAX). Persons with a positive family history and the highest measured CAOX index had a predicted lifetime risk of 88.8 percent. Biochemical factors affecting lithogenesis were hypercalciuria, hyperoxaluria, and low urine volume. CONCLUSION: Future research should characterize the geographic boundaries of a southeastern "stone-belt" and explore genetic and dietary hypotheses that might explain it.
Assuntos
Cálculos Renais/epidemiologia , Adulto , Idoso , Oxalato de Cálcio/urina , Indústria de Laticínios , Humanos , Incidência , Cálculos Renais/induzido quimicamente , Cálculos Renais/urina , Modelos Logísticos , Masculino , Metalurgia , Pessoa de Meia-Idade , Ocupações , Prevalência , Fatores de Risco , Tennessee/epidemiologia , Urânio/efeitos adversos , Urina/químicaRESUMO
Deficiency of uridine monophosphate synthase (DUMPS) is a monogenic autosomal recessive disorder in cattle, resulting in early embryonic death of homozygous offspring. To identify the mutation responsible for DUMPS, liver RNA from identified, DUMPS heterozygous animals from the Holstein and Red Holstein breeds was reverse transcribed. Amplification of cDNA with sequence-specific primers and subsequent sequencing of the PCR products revealed a mutation (C-->T) with the loss of an AvaI site at codon 405, resulting in a premature stop codon with a truncated C-terminal catalytic subunit of the protein. A direct DNA test based on PCR was developed and subsequently tested on 102 animals. Complete concurrence of deficiency of UMPS and the presence of the described point mutation in heterozygous animals was observed, thus confirming this point mutation as the basic defect in DUMPS cattle.
Assuntos
Doenças dos Bovinos/genética , Complexos Multienzimáticos/genética , Orotato Fosforribosiltransferase/genética , Orotidina-5'-Fosfato Descarboxilase/genética , Mutação Puntual , Erros Inatos do Metabolismo da Purina-Pirimidina/veterinária , Animais , Sequência de Bases , Bovinos , Doenças dos Bovinos/enzimologia , DNA/genética , Análise Mutacional de DNA , Feminino , Genótipo , Heterozigoto , Masculino , Dados de Sequência Molecular , Complexos Multienzimáticos/deficiência , Orotato Fosforribosiltransferase/deficiência , Orotidina-5'-Fosfato Descarboxilase/deficiência , Linhagem , Reação em Cadeia da Polimerase , Erros Inatos do Metabolismo da Purina-Pirimidina/enzimologia , Erros Inatos do Metabolismo da Purina-Pirimidina/genética , Transcrição GênicaRESUMO
BACKGROUND: The onset of multiple sclerosis after the age of 50 years is rare. We report four patients with optic neuritis and oligoclonal bands or increased IgG production in the cerebrospinal fluid. Three of them subsequently developed clinically definite multiple sclerosis. PATIENTS: Four apparently healthy women, 62, 56, 50 and 50 years of age, presented with progressive visual loss, three patients in one eye and one patient in both eyes. The diagnostic work-up revealed no findings indicating an ischemic process, an infectious, systemic inflammatory, or neoplastic disease. Examination of the cerebrospinal fluid revealed oligoclonal bands and/or increased production of IgG. Visual acuity recovered during the following weeks to 8 months. Three of the 4 patients subsequently developed additional neurologic signs compatible with multiple sclerosis. CONCLUSION: Optic neuritis can be the presenting sign of multiple sclerosis even after the age of 50.
Assuntos
Esclerose Múltipla/diagnóstico , Neurite Óptica/diagnóstico , Diagnóstico Diferencial , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Imunoglobulina G/líquido cefalorraquidiano , Imunoglobulinas/líquido cefalorraquidiano , Pessoa de Meia-Idade , Esclerose Múltipla/fisiopatologia , Exame Neurológico , Bandas Oligoclonais , Nervo Óptico/fisiopatologia , Neurite Óptica/etiologia , Neurite Óptica/fisiopatologiaRESUMO
Laminin, the major glycoprotein of basement membranes, actively supports cell migration in development, tissue repair, tumor growth, metastasis, and other pathological processes. Previously we have shown that the locomotion of murine skeletal myoblasts is specifically and significantly enhanced on laminin but not on other matrix proteins. One of the major laminin receptors of myoblasts is the alpha 7 beta 1 integrin, which was first described in human MeWo melanoma cells and Rugli glioblastoma cells. In order to investigate and directly test the role of the alpha 7 integrin in cell migration on laminin, we expressed the murine alpha 7B splice variant in human 293 kidney cells and 530 melanoma cells which cannot migrate on laminin and are devoid of endogenous alpha 7. Northern blotting of the transfected cells showed that the alpha 7 mRNA was expressed efficiently, and the protein was detected on the cell surface by immunofluorescence and fluorescence-activated cell sorter analysis. Cell motility measurements by computer-assisted time-lapse videomicroscopy of the alpha 7-transfected cells revealed an 8-10-fold increase in motility on laminin-1 and its E8 fragment, but not on fibronectin. Mock-transfected cells did not migrate significantly of alpha 7-transfected 293 cells through laminin-coated filters in a Boyden chamber assay was significantly enhanced in comparison to mock transfected cells. These findings prove that alpha 7 integrin expression confers a gain of function-motile phenotype to immobile cells and may be responsible for transduction of the laminin-induced cell motility.