Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Hepatology ; 69(6): 2636-2651, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30779441

RESUMO

There is an urgent need for an easily assessable preoperative test to predict postoperative liver function recovery and thereby determine the optimal time point of liver resection, specifically as current markers are often expensive, time consuming, and invasive. Emerging evidence suggests that microRNA (miRNA) signatures represent potent diagnostic, prognostic, and treatment-response biomarkers for several diseases. Using next-generation sequencing as an unbiased systematic approach, 554 miRNAs were detected in preoperative plasma of 21 patients suffering from postoperative liver dysfunction (LD) after liver resection and 27 matched controls. Subsequently, we identified a miRNA signature-consisting of miRNAs 151a-5p, 192-5p, and 122-5p-that highly correlated with patients developing postoperative LD after liver resection. The predictive potential for postoperative LD was subsequently confirmed using real-time PCR in an independent validation cohort of 98 patients. Ultimately, a regression model of the two miRNA ratios 151a-5p to 192-5p and 122-5p to 151a-5p was found to reliably predict postoperative LD, severe morbidity, prolonged intensive care unit and hospital stays, and even mortality before an operation with a remarkable accuracy, thereby outperforming established markers of postoperative LD. Ultimately, we documented that miRNA ratios closely followed liver function recovery after partial hepatectomy. Conclusion: Our data demonstrate the clinical utility of an miRNA-based biomarker to support the selection of patients undergoing partial hepatectomy. The dynamical changes during liver function recovery indicate a possible role in individualized patient treatment. Thereby, our data might help to tailor surgical strategies to the specific risk profile of patients.


Assuntos
Hepatectomia/efeitos adversos , Hepatopatias/sangue , Neoplasias Hepáticas/cirurgia , MicroRNAs/genética , Transcriptoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Hepatectomia/métodos , Humanos , Hepatopatias/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/patologia , Valor Preditivo dos Testes , Prognóstico , Análise de Regressão , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento
2.
Ecotoxicol Environ Saf ; 129: 189-98, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27045919

RESUMO

Organisms in the aquatic environment are exposed to a variety of substances of numerous chemical classes. The unintentional co-occurrence of pharmaceuticals and other contaminants of emerging concern may pose risk to non-target organisms. In this study, individual and binary mixture toxicity experiments of selected pharmaceuticals (ibuprofen and ciprofloxacin) and chlorophenols (2.4-dichlorophenol (2,4-DCP) and 3-chlorophenol (3-CP)) have been performed with freshwater algae Chlorella vulgaris. All experiments have been carried out according to the 96-h algal growth inhibition test OECD No. 201. Binary mixture tests were conducted using proportions of the respective IC50s in terms of toxic unit (TU). The mixture concentration-response curve was compared to predicted effects based on both the concentration addition (CA) and the independent action (IA) model. Additionally, the Combination Index (CI)-isobologram equation method was used to assess toxicological interactions of the binary mixtures. All substances individually tested had a significant effect on C. vulgaris population density and revealed IC50 values <100mgL(-1) after exposure period of 96-h. The toxic ranking of these four compounds to C. vulgaris was 2,4-DCP>ciprofloxacin>3-CP>ibuprofen. Generally, it can be concluded from this study that toxic mixture effects of all tested chemicals to C. vulgaris are higher than the individual effect of each mixture component. It could be demonstrated that IC50 values of the tested mixtures predominately lead to additive effects. The CA model is appropriate to estimate mixture toxicity, while the IA model tends to underestimate the joint effect. The CI-isobologram equation method predicted the mixtures accurately and elicited synergism at low effect levels for the majority of tested combinations.


Assuntos
Chlorella vulgaris/efeitos dos fármacos , Clorofenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Ciprofloxacina/toxicidade , Água Doce , Ibuprofeno/toxicidade , Concentração Inibidora 50
3.
Bone ; 131: 115104, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31683019

RESUMO

MicroRNAs control the activity of a variety of genes that are pivotal to bone metabolism. Therefore, the clinical utility of miRNAs as biomarkers and drug targets for bone diseases certainly merits further investigation. This study describes the use of an animal model of postmenopausal osteoporosis to generate a comprehensive dataset on miRNA regulation in bone tissue and peripheral blood during bone loss and specifically anti-resorptive and osteo-anabolic treatment. Forty-two Sprague-Dawley rats were randomized to SHAM surgery (n=10) or ovariectomy (OVX, n=32). Eight weeks after surgery, OVX animals were further randomized to anti-resorptive treatment with zoledronate (n=11), osteo-anabolic treatment with teriparatide (n=11), or vehicle treatment (n=10). After 12 weeks of treatment, bone and serum samples were used for microRNA analysis using next-generation sequencing (NGS), mRNA levels using RT-qPCR, and bone microarchitecture analysis using nanoCT. Ovariectomy resulted in loss of trabecular bone, which was fully rescued using osteo-anabolic treatment, and partially rescued using anti-resorptive treatment. NGS revealed that both, anti-resorptive and anabolic treatment had a significant impact on miRNA levels in bone tissue and serum: out of 426 detected miRNAs, 46 miRNAs were regulated by teriparatide treatment an d 10 by zoledronate treatment (p-adj.<0.1). Interestingly, teriparatide and zoledronate treatment were able to revert miRNA changes in tissue and serum of untreated OVX animals, such as the up-regulation of miR-203a-3p, a known osteo-inhibitory miRNA. We confirmed previously established mechanisms of miR-203a by analyzing its direct target Dlx5 in femoral head. Our data reveal a significant effect of ovariectomy-induced bone loss, as well as the two major types of anti-osteoporotic treatment on miRNA transcription in femoral head tissue. These changes are associated with altered activity of target genes relevant to bone formation, such as Dlx5. The observed effects of bone loss and treatment response on miRNA levels in bone are also reflected in the peripheral blood, suggesting the possibility of minimally-invasive monitoring of bone-derived miRNAs using liquid biopsies.


Assuntos
MicroRNAs , Osteoporose Pós-Menopausa , Animais , Densidade Óssea , Osso e Ossos , Difosfonatos , Modelos Animais de Doenças , Feminino , Humanos , MicroRNAs/genética , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/genética , Ovariectomia , Ratos , Ratos Sprague-Dawley , Teriparatida/farmacologia , Teriparatida/uso terapêutico
4.
Sci Rep ; 8(1): 4867, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29559644

RESUMO

The assessment of bone quality and the prediction of fracture risk in idiopathic osteoporosis (IOP) are complex prospects as bone mineral density (BMD) and bone turnover markers (BTM) do not indicate fracture-risk. MicroRNAs (miRNAs) are promising new biomarkers for bone diseases, but the current understanding of the biological information contained in the variability of miRNAs is limited. Here, we investigated the association between serum-levels of 19 miRNA biomarkers of idiopathic osteoporosis to bone microstructure and bone histomorphometry based upon bone biopsies and µCT (9.3 µm) scans from 36 patients. Four miRNAs were found to be correlated to bone microarchitecture and seven miRNAs to dynamic histomorphometry (p < 0.05). Three miRNAs, namely, miR-29b-3p, miR-324-3p, and miR-550a-3p showed significant correlations to histomorphometric parameters of bone formation as well as microstructure parameters. miR-29b-3p and miR-324-p were found to be reduced in patients undergoing anti-resorptive therapy. This is the first study to report that serum levels of bone-related miRNAs might be surrogates of dynamic histomorphometry and potentially reveal changes in bone microstructure. Although these findings enhance the potential value of circulating miRNAs as bone biomarkers, further experimental studies are required to qualify the clinical utility of miRNAs to reflect dynamic changes in bone formation and microstructure.


Assuntos
Osso e Ossos/patologia , Osteoporose Pós-Menopausa/genética , Osteoporose/genética , Adulto , Biomarcadores/sangue , Densidade Óssea/genética , Osso e Ossos/metabolismo , Osso e Ossos/ultraestrutura , MicroRNA Circulante/análise , MicroRNA Circulante/genética , Estudos Transversais , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/fisiologia , Pessoa de Meia-Idade , Osteogênese/genética , Osteogênese/fisiologia , Osteoporose/sangue , Osteoporose/metabolismo , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/metabolismo , Fraturas por Osteoporose/genética , Fatores de Risco
5.
J Clin Endocrinol Metab ; 101(11): 4125-4134, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27552543

RESUMO

CONTEXT: Established bone turnover markers do not reflect fracture risk in idiopathic male and premenopausal osteoporosis and the role of microRNAs (miRNAs) in these patients is currently unclear. miRNAs are a class of small non-coding RNAs that regulate gene expression and bone tissue homeostasis. They are considered a new class of endocrine regulators with promising potential as biomarkers. OBJECTIVE: Evaluation of circulating miRNA signatures in male and female subjects with idiopathic and postmenopausal osteoporotic low-traumatic fractures. DESIGN, SETTING, AND PATIENTS: This was a case-control study of cross-sectional design of 36 patients with prevalent low-traumatic fractures and 39 control subjects Main Outcome Measures: One hundred eighty-seven miRNAs were quantified in serum by qPCR, compared between groups and correlated with established bone turnover markers. RESULTS: Significant differences in serum levels of circulating miRNAs were identified in all three subgroups (46 in premenopausal, 52 in postmenopausal, 55 in male). A set of 19 miRNAs was consistently regulated in all three subgroups. Eight miRNAs [miR-152-3p, miR-30e-5p, miR-140-5p, miR-324-3p, miR-19b-3p, miR-335-5p, miR-19a-3p, miR-550a-3p] were excellent discriminators of patients with low-traumatic fractures, regardless of age and sex, with area under the curve values > 0.9. The 11 remaining miRNAs showed area under the curve values between 0.81 and 0.89. Correlation analysis identified significant correlations between miR-29b-3p and P1NP, and miR-365-5p and iPTH, TRAP5b, P1NP and Osteocalcin, as well as BMDL1-L4 and miR-19b-3p, miR-324-3p, miR-532-5p, and miR-93-5p. CONCLUSIONS: Specific serum miRNA profiles are strongly related to bone pathologies. Therefore miRNAs might be directly linked to bone tissue homeostasis. In particular, miR-29b-3p has previously been reported as regulator of osteogenic differentiation and could serve as a novel marker of bone turnover in osteoporotic patients as a member of a miRNA signature.


Assuntos
MicroRNAs/sangue , Osteoporose/sangue , Fraturas por Osteoporose/sangue , Pós-Menopausa/sangue , Pré-Menopausa/sangue , Absorciometria de Fóton , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem
6.
J Invest Dermatol ; 119(4): 842-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12406329

RESUMO

Inflammatory dendritic epidermal cells present in skin lesions of the atopic eczema/dermatitis syndrome display the highest expression of the high-affinity receptor for IgE (FcepsilonRI), ever detected on human antigen-presenting cells. Owing to the instability of the FcepsilonRI (alphagammagamma) complex and fast cleavage from the cell surface during the interleukin-4/granulocyte-macrophage colony-stimulating factor driven in vitro differentiation of monocytes, a method to generate inflammatory dendritic epidermal cells was not at our disposal in the past and the amount of ex vivo isolated inflammatory dendritic epidermal cells available for functional assays was limited. Therefore, information about the role of inflammatory dendritic epidermal cells and FcepsilonRI on this dendritic cell subtype in atopic and inflammatory skin diseases is completely missing. In this study, we were able to: (i) increase the expression of a functional FcepsilonRI complex on the cell surface of immature monocyte-derived dendritic cells from atopic donors by creating a reducing microenvironment; (ii) enhance significantly the intracellular pool of the FcepsilonRIgamma chains, which is the limiting parameter for the FcepsilonRI surface expression; and (iii) generate monocyte-derived dendritic cells displaying the phenotypical characteristics of inflammatory dendritic epidermal cells, producing high amounts of proinflammatory cytokines and chemokines similar to the cytokines found in lesional skin of the atopic eczema/dermatitis syndrome. Altogether the high expression of functional FcepsilonRI on these cells enables us for the first time to study inflammatory dendritic epidermal cells and FcepsilonRI-mediated mechanisms of inflammatory dendritic epidermal cells in vitro, in order to shed light on the putative role of this important cell type in the atopic eczema/dermatitis syndrome.


Assuntos
Células Dendríticas/fisiologia , Dermatite Atópica/imunologia , Receptores de IgE/análise , Pele/imunologia , Células Cultivadas , Quimiocinas/biossíntese , Citocinas/biossíntese , Ditiotreitol/farmacologia , Humanos , Oxirredução , Receptores de IgE/fisiologia , Pele/citologia
7.
J Invest Dermatol ; 119(4): 870-5, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12406333

RESUMO

Patients with atopic dermatitis display substantial immunologic abnormalities, among which elevated total IgE is considered as a hallmark; however, a subgroup of atopic dermatitis patients exhibits normal IgE levels, but mechanisms contributing to the so-called "intrinsic" or "nonallergic" form of atopic dermatitis are obscure. In order to unravel similarities and differences of both atopic dermatitis subtypes, the phenotype of monocytes, total serum IgE levels, and serum levels of cytokines regulating the IgE production from nonatopic individuals and patients with allergic rhinitis, and extrinsic and intrinsic atopic dermatitis were measured. Concomitantly, genomic DNA probes of all subjects were analyzed for single nucleotide polymorphisms of candidate genes of structures involved in the regulation of the IgE synthesis, such as interleukin-4 and the interleukin-4R/interleukin-13R. Our data show that the surface expression of the high- and low-affinity receptor for IgE (FcepsilonRI and FcepsilonRII/CD23) and the interleukin-4Ralpha chain were significantly elevated in monocytes from patients with extrinsic atopic dermatitis. Furthermore, serum levels of interleukin-13 were significantly increased in patients with intrinsic atopic dermatitis. In addition, the frequency of the interleukin-4Ralpha polymorphism C3223T and the interleukin-4 polymorphism C590T tended to be higher in extrinsic atopic dermatitis than in intrinsic atopic dermatitis. Altogether our findings indicate that intrinsic atopic dermatitis patients exhibit phenotypic and immunologic features, which differ from those of patients with extrinsic atopic dermatitis or other atopic disorders.


Assuntos
Dermatite Atópica/imunologia , Interleucina-4/genética , Monócitos/imunologia , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-4/genética , Receptores de Interleucina/genética , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Imunofenotipagem , Interleucina-13/sangue , Subunidade alfa1 de Receptor de Interleucina-13 , Interleucina-5/sangue , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Receptores de IgE/análise , Receptores de Interleucina-13
8.
J Clin Psychiatry ; 67(11): 1776-81, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17196059

RESUMO

OBJECTIVE: Psychomotor disturbances can frequently be found in depressed patients and may have an important influence on the ability to drive. Additionally, effects of sedation, as seen with some antidepressants, probably impair driving performance. The present study was designed to evaluate the effects of antidepressant monotherapy on psychomotor functions related to car-driving skills in depressive patients in a routine clinical setting. METHOD: Inpatients (N = 100) who met the ICD-10 and DSM-IV criteria for major depressive disorder were tested under steady-state plasma level conditions prior to being discharged to out-patient treatment. The study ran from January 2004 through March 2005. All patients participated voluntarily and gave informed consent. According to the German guidelines for road and traffic safety, data were collected with the computerized Act & React Testsystem ART-90 and the Wiener Testsystem, measuring visual perception, reaction time, selective attention, vigilance, and stress tolerance. Psychopathologic symptoms were rated with the Hamilton Rating Scale for Depression. RESULTS: Before discharge to outpatient treatment, 24% of the patients tested were without clinically relevant psychomotor disturbances. In 60% of the cases, mild to moderate impairments could be seen, and about 16% of the patients were considered as severely impaired in psychomotor functions related to car-driving abilities. Data show that patients treated with selective serotonin reuptake inhibitors (SSRIs) or the noradrenergic and specific serotonergic antidepressant (NaSSA) mirtazapine had an altogether better test performance in comparison with patients receiving tricyclic antidepressants (TCAs). Differences were most pronounced in measures of reactivity, stress tolerance, and selective attention. Statistically significant differences between patients treated with TCAs or the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine could not be found. Among the newer antidepressants there is an advantage for patients treated with mirtazapine, especially in tasks with high multi-channel perception and output demands. CONCLUSION: About 16% of depressive patients discharged from hospital to outpatient treatment must be considered unfit to drive. In 60% of the cases, patients performed at a questionable level of fitness for driving, and it seems justified to counsel patients individually, taking into account compensational factors. Data point to an advantage for patients treated with SSRIs or mirtazapine when compared with TCAs or venlafaxine. However, causal relationships cannot be drawn from our data.


Assuntos
Antidepressivos/efeitos adversos , Condução de Veículo , Transtorno Depressivo Maior/tratamento farmacológico , Transtornos Psicomotores/etiologia , Fases do Sono , Adulto , Idoso , Nível de Alerta/efeitos dos fármacos , Atenção/efeitos dos fármacos , Transtorno Depressivo Maior/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicomotores/induzido quimicamente , Tempo de Reação/efeitos dos fármacos , Percepção Visual/efeitos dos fármacos
9.
Psychiatr Prax ; 31 Suppl 1: S158-60, 2004 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-15570539

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effects of antipsychotics on memory functions in schizophrenic patients under clinical routine conditions. METHOD: Schizophrenic patients (n = 111) before discharge to outpatient treatment were evaluated on verbal memory function. Data were analyzed according to pharmacological treatment controlling for age. RESULTS: We observed that treatment with atypical antipsychotics (n = 80) compared with conventional neuroleptics (n = 31) was significantly associated with a more favorable effect on memory function. In short-term- and working-memory and retention a clear advantage of atypical antipsychotics could be seen. CONCLUSIONS: Results from this study suggest that even under clinical routine conditions atypical antipsychotics have an advantage on memory function when compared with conventional antipsychotics.


Assuntos
Memória de Curto Prazo/efeitos dos fármacos , Testes Neuropsicológicos , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Aprendizagem Verbal/efeitos dos fármacos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
10.
Psychiatr Prax ; 30(Suppl 2): 106-109, 2003 May.
Artigo em Alemão | MEDLINE | ID: mdl-13130351

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effects of atypical antipsychotics on cognitive function in schizophrenic patients under clinical routine conditions. METHOD: Schizophrenic patients (n = 78) were evaluated on neuropsychological tests of attention, short-term- and working memory, learning, long-term memory (retention) and executive function. Data were analyzed according to medication, severity of illness and age. RESULTS: We observed that treatment with atypical antipsychotics compared to conventional neuroleptics was significantly associated with a more favorable effect on cognitive function. Especially in short-term memory and retention a clear advantage of atypical antipsychotics could be seen. CONCLUSION: Results from this study suggest that even under clinical routine conditions atypical antipsychotics have an advantage on cognitive function when compared with conventional neuroleptics.

11.
Psychiatr Prax ; 30 Suppl 2: S106-9, 2003 May.
Artigo em Alemão | MEDLINE | ID: mdl-14509053

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effects of atypical antipsychotics on cognitive function in schizophrenic patients under clinical routine conditions. METHOD: Schizophrenic patients (n = 78) were evaluated on neuropsychological tests of attention, short-term- and working memory, learning, long-term memory (retention) and executive function. Data were analyzed according to medication, severity of illness and age. RESULTS: We observed that treatment with atypical antipsychotics compared to conventional neuroleptics was significantly associated with a more favorable effect on cognitive function. Especially in short-term memory and retention a clear advantage of atypical antipsychotics could be seen. CONCLUSION: Results from this study suggest that even under clinical routine conditions atypical antipsychotics have an advantage on cognitive function when compared with conventional neuroleptics.


Assuntos
Antipsicóticos/efeitos adversos , Transtornos Cognitivos/induzido quimicamente , Testes Neuropsicológicos , Pirenzepina/análogos & derivados , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Adulto , Antipsicóticos/uso terapêutico , Benzodiazepinas , Clozapina/efeitos adversos , Clozapina/uso terapêutico , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Quimioterapia Combinada , Feminino , Haloperidol/efeitos adversos , Haloperidol/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina , Pirenzepina/efeitos adversos , Pirenzepina/uso terapêutico , Vigilância de Produtos Comercializados , Risperidona/efeitos adversos , Risperidona/uso terapêutico
12.
J Clin Psychopharmacol ; 24(2): 155-60, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15206662

RESUMO

Cognitive and psychomotor impairments are a core feature of most patients with schizophrenia and may have an important influence on driving ability. The present study investigated the effects of neuroleptic monotherapy on psychomotor functions related to car driving skills in schizophrenic patients. Consecutively admitted schizophrenic inpatients (n = 120) were tested under steady state plasma level conditions before discharge to outpatient treatment. Patients met the International Classification of Diseases, Tenth Revision criteria for schizophrenia. The study followed a naturalistic nonrandomized design. Data were collected with the computerized Act & React Testsystem and were analyzed according to medication, severity of illness, and age. Only 32.5% of the schizophrenic inpatients passed the tests without major impairments. Patients treated with atypical neuroleptics or clozapine showed a better test performance on skills related to driving ability when compared with patients on typical neuroleptics. Differences were most pronounced in measures of divided attention, stress tolerance, and attention. Data also suggest that treatment with clozapine had an overall positive impact on measures of reactivity and stress tolerance. These results show that even under steady state pharmacologic conditions psychomotor functions of most schizophrenic patients partly remitted must be considered as impaired. To evaluate these effects, a systematic neuropsychologic examination is recommended.


Assuntos
Antipsicóticos/efeitos adversos , Condução de Veículo/psicologia , Desempenho Psicomotor/efeitos dos fármacos , Adolescente , Adulto , Clozapina/efeitos adversos , Feminino , Flupentixol/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Percepção Visual/efeitos dos fármacos
13.
J Allergy Clin Immunol ; 112(1): 141-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12847491

RESUMO

BACKGROUND: The oral mucosa represents a unique immunologic unit with a high frequency of native allergen contact within the gastrointestinal tract in which immune tolerance is the natural outcome of allergen contact. Although Langerhans' cells (LC), known to play a crucial role in initiating allergen-dependent immune responses in the skin, have also been detected in the oral mucosa, little is known about their phenotype and exact physiologic role. OBJECTIVE: To elucidate whether LC from oral mucosa (oLC) differ from skin LC (sLC), these cells were subjected to detailed comparative analysis. METHODS: Crude epidermal and oral mucosa cell suspensions were prepared by trypsinization. oLC and sLC were compared phenotypically by flow cytometry techniques and functionally in T-cell proliferation assays. RESULTS: In contrast to sLC, freshly isolated oLC expressed significantly higher amounts of MHC class I and II, as well as costimulatory molecules CD40, CD80/B7.1, and CD86/B7.2. oLC displayed FcgammaRIII/CD16 and FcgammaRI/CD64. Most surprisingly, oLC constitutively expressed the high affinity receptor for IgE (FcepsilonRI) even in nonatopic donors. FcepsilonRI expression on oLC was further increased and correlated with the serum IgE levels in atopic individuals. oLC showed a higher allogeneic stimulatory activity than sLC, whereas the activation of autologous T cells correlated to the FcepsilonRI expression. CONCLUSION: Taken together, our results strongly indicate that oLC profoundly differ from their skin counterparts. The constitutive high expression of FcepsilonRI on oLC could point to particular skills of these cells within the regional immune system of the oral mucosa.


Assuntos
Células Dendríticas/imunologia , Células de Langerhans/imunologia , Mucosa Bucal/imunologia , Receptores de IgE/análise , Antígenos CD/análise , Antígeno B7-1/análise , Antígeno B7-2 , Antígenos CD40/análise , Antígenos de Histocompatibilidade Classe I/análise , Antígenos de Histocompatibilidade Classe II/análise , Humanos , Glicoproteínas de Membrana/análise , Linfócitos T/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA