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1.
J Endocrinol Invest ; 47(6): 1477-1485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38112911

RESUMO

PURPOSE: MKNR3 is a paternally expressed gene whose mutations are the main cause of central precocious puberty (CPP). Protein circulating levels can be easily measured, as demonstrated in idiopathic CPP and healthy controls. No data are available for patients harboring an MKRN3 mutation. Our aim was to perform MKRN3 mutation screening and to investigate if circulating protein levels could be a screening tool to identify MKRN3 mutation in CPP patients. METHODS: We enrolled 140 CPP girls and performed MKRN3 mutation analysis. Patients were stratified into two groups: idiopathic CPP (iCPP) and MKRN3 mutation-related CPP (MKRN3-CPP). Clinical characteristics were collected. Serum MKRN3 values were measured by a commercially available ELISA assay kit in MKRN3-CPP and a subgroup of 15 iCPP patients. RESULTS: We identified 5 patients with MKRN3 mutations: one was a novel mutation (p.Gln352Arg) while the others were previously reported (p.Arg328Cys, p.Arg345Cys, p.Pro160Cysfs*14, p.Cys410Ter). There was a significant difference in circulating MKRN3 values in MKRN3-CPP compared to iCPP (p < 0.001). In MKRN3-CPP, the subject harboring Pro160Cysfs*14 presented undetectable levels. Subjects carrying the missense mutations p.Arg328Cys and p.Gln352Arg showed divergent circulating protein levels, respectively 40.56 pg/mL and undetectable. The patient with the non-sense mutation reported low but measurable MKRN3 levels (12.72 pg/mL). CONCLUSIONS: MKRN3 defect in patients with CPP cannot be predicted by MKRN3 circulating levels, although those patients presented lower protein levels than iCPP. Due to the great inter-individual variability of the assay and the lack of reference values, no precise cut-off can be identified to suspect MKRN3 defect.


Assuntos
Mutação , Puberdade Precoce , Ubiquitina-Proteína Ligases , Humanos , Puberdade Precoce/genética , Puberdade Precoce/sangue , Puberdade Precoce/diagnóstico , Feminino , Ubiquitina-Proteína Ligases/genética , Criança , Ribonucleoproteínas/genética , Ribonucleoproteínas/sangue , Pré-Escolar , Análise Mutacional de DNA , Estudos de Casos e Controles , Biomarcadores/sangue
2.
Front Genet ; 14: 1031074, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37609037

RESUMO

Rapid-onset Obesity with Hypothalamic dysfunction, Hypoventilation and Autonomic Dysregulation (ROHHAD) is a rare, life-threatening, pediatric disorder of unknown etiology, whose diagnosis is made difficult by poor knowledge of clinical manifestation, and lack of any confirmatory tests. Children with ROHHAD usually present with rapid onset weight gain which may be followed, over months or years, by hypothalamic dysfunction, hypoventilation, autonomic dysfunction, including impaired bowel motility, and tumors of neural crest origin. Despite the lack of evidence of inheritance in ROHHAD, several studies have been conducted in recent years that have explored possible genetic origins, with unsuccessful results. In order to broaden the search for possible genetic risk factors, an attempt was made to analyse the non-coding variants in two trios (proband with parents), recruited in the Gaslini Children's Hospital in Genoa (Italy). Both patients were females, with a typical history of ROHHAD. Gene variants (single nucleotide variants, short insertions/deletions, splice variants or in tandem expansion of homopolymeric tracts) or altered genomic regions (copy number variations or structural variants) shared between the two probands were searched. Currently, we have not found any potentially pathogenic changes, consistent with the ROHHAD clinical phenotype, and involving genes, regions or pathways shared between the two trios. To definitively rule out the genetic etiology, third-generation sequencing technologies (e.g., long-reads sequencing, optical mapping) should be applied, as well as other pathways, including those associated with immunological and autoimmune disorders, should be explored, making use not only of genomics but also of different -omic datasets.

3.
Diabet Med ; 27(9): 1041-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20722678

RESUMO

AIMS: We evaluated the impact of a continuous quality improvement effort implemented by a network of Italian diabetes clinics operating in the national healthcare system. METHODS: This was a controlled before-and-after study involving 95 centres, of which 67 joined the initiative since 2004 (group A) and 18 were first involved in 2007 (group B, control). All centres used electronic medical record systems. Information on quality indicators was extracted for the period 2004-2007. Data were centrally analysed anonymously and results were published annually. Each centre's performance was ranked against the 'best performers'. We compared quality indicators between the two groups of centres over 4 years. RESULTS: Over 100 000 Type 2 diabetes mellitus patients were evaluated annually. The proportion of patients with glycated haemoglobin levels < 7% increased by 6% in group A (2007-2004 difference) and by 1.3% in group B. The proportion of patients with low-density lipoprotein-cholesterol < 100 mg/dl improved by over 10% in both groups. The rate of patients with blood pressure values < or = 130/85 mmHg increased in group A (+6.4%), but not in group B (-1.4%). The use of insulin increased in group A only (+5.2%), while the use of statins increased by over 20% in both groups. CONCLUSIONS: A physician-led quality improvement effort, based on the systematic evaluation of routine data, is effective in improving the performance of a large number of diabetes clinics. The small percentage increase in the number of patients at target, if applied to large numbers of patients, would translate into a significant impact on public health.


Assuntos
Instituições de Assistência Ambulatorial/normas , Diabetes Mellitus Tipo 2/terapia , Sistemas Computadorizados de Registros Médicos/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Idoso , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Itália/epidemiologia , Masculino , Avaliação de Programas e Projetos de Saúde , Indicadores de Qualidade em Assistência à Saúde , Resultado do Tratamento
4.
Nanotechnology ; 20(29): 295203, 2009 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-19567959

RESUMO

For various types of ensembles of metal nanorods, the frequencies of longitudinal and transverse plasmons were calculated and correlations between the plasmon frequency shifts and the topology of nanorod arrays were found. The theoretical predictions were compared with the experimentally determined optical absorption in arrays of polymer-terminated Au nanorods obtained by self-assembly in selective solvents.

5.
Diabetes Care ; 17(12): 1488-90, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7882824

RESUMO

OBJECTIVE: To test the hypothesis that the consumption of dairy products, including fluid cows' milk and cheese, is related to the incidence of insulin-dependent diabetes mellitus (IDDM), we correlated incidence rates in children 0-14 years of age with cows' milk and cheese consumption in nine regions of a single country, Italy. RESEARCH DESIGN AND METHODS: Data on the incidence of IDDM were derived from the only nine Italian regions where primary and secondary sources of ascertainment were available for 1991. Data on fluid cows' milk and cheese consumption in the corresponding year in each region were obtained from the National Institute of Statistics. RESULTS: The correlation between fluid milk consumption and incidence of IDDM in Italy was 0.84 (P < 0.004, Poisson regression analysis). Cheese consumption was not related to IDDM incidence. CONCLUSIONS: The results indicate that there is a relationship, even in a single country, between dairy product consumption and the incidence of IDDM that is confined to fluid milk consumption. Cows' milk may contain a triggering factor for the development of diabetes, but the high incidence of IDDM in Sardinia and in other countries worldwide cannot be explained simply by the quantity of fluid cows' milk consumed.


Assuntos
Laticínios , Diabetes Mellitus Tipo 1/epidemiologia , Dieta , Leite , Adolescente , Animais , Criança , Pré-Escolar , Humanos , Incidência , Lactente , Recém-Nascido , Itália/epidemiologia
6.
Diabetes Care ; 21(6): 925-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9614609

RESUMO

OBJECTIVE: The aim of this study was to determine the impact of genetic or environmental factors on the age or time of onset of IDDM by studying pairs of twins and siblings concordant for the disease. RESEARCH DESIGN AND METHODS: From 404 twin pairs referred to a diabetic twin study, we selected pairs concordant for IDDM: 1) 116 identical pairs with an index twin diagnosed diabetic under age 60 years and 2) 12 identical and 12 nonidentical matched twin pairs. From 972 families referred to a population-based diabetic family study, we selected sibling pairs with IDDM: 33 pairs with an index case diagnosed diabetic under age 21 years. Twin and sibling pairs were analyzed for intraclass correlations for age and time of diagnosis. RESULTS: Of twins concordant for IDDM, the age at diagnosis correlated 1) in 116 identical pairs (R = 0.94; P < 0.000001) and 2) more closely in 12 identical twins (R = 0.96, P < 0.000001) than 12 nonidentical twins (R = 0.59, P = 0.046). Of 33 sibling pairs with IDDM, the age, but not the time, of diagnosis was correlated (R = 0.53, P = 0.0016). CONCLUSIONS: Correlations within pairs of twins and siblings for age, not time, at diagnosis suggest that much of the variability of the age at diagnosis of IDDM is genetically determined.


Assuntos
Idade de Início , Diabetes Mellitus Tipo 1/genética , Doenças em Gêmeos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Familiar , Análise de Regressão
7.
Diabetes Care ; 23(2): 228-33, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10868836

RESUMO

OBJECTIVE: To determine the isotypes and clonality of antibodies to GAD (GADA) and IA-2 (IA-2A) in patients with type 1 and type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied the following consecutive series of patients who attended a diabetes center for antibodies to GADA and IA-2A: 52 newly diagnosed type 1 diabetic patients, 199 type 2 diabetic patients, 200 control patients, and a cohort of 34 nondiabetic identical twins of patients with type 1 diabetes (15 of whom developed diabetes) who were followed prospectively. RESULTS: GADA or IA-2A were detected in 37 (71%) type 1 diabetic patients compared with only 10 (5%) type 2 diabetic patients (P<0.0001). Both GAD and IA-2 antibodies, regardless of the type of diabetes, were usually subclass restricted to IgG1 and were polyclonal. IgM, IgG3, and IgE isotypes were also detected, but all isotypes of GADA and IA-2A were less prevalent than IgG1 (P<0.017 for either antibody). There was no evidence of spreading or switching of isotypes before the onset of type 1 diabetes. CONCLUSIONS: These observations suggest that the pathogenesis of antigen-specific antibodies in type 1 and type 2 diabetes is similar and probably involves a chronic nonrandom antigen-driven polyclonal B-cell activation that is consistent with a Th1-type immune response.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/imunologia , Glutamato Descarboxilase/imunologia , Isotipos de Imunoglobulinas/sangue , Isoenzimas/imunologia , Adulto , Idade de Início , Estudos de Coortes , Europa (Continente)/etnologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Valores de Referência , Gêmeos Monozigóticos , População Branca
8.
J Diabetes Complications ; 17(2 Suppl): 30-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12623166

RESUMO

Diabetes mellitus is characterized by oxidative stress, which in turn determines endothelial dysfunction. It has been recently demonstrated that gliclazide, a second-generation sulfonylurea with antioxidant properties, is able to protect endothelial function in animal models of diabetes. In streptozotocin-induced diabetic rats, gliclazide prevented endothelial dysfunction when given orally and improved the impaired relaxations to exogenous nitric oxide (NO) when applied on aortic segments. Moreover, gliclazide was able to inhibit glycosylated oxyhemoglobin-induced endothelial dysfunction both in animal and human microvessels. All these effects were not shared by glibenclamide, but were mimicked by vitamin C or superoxide dismutase (SOD), thus suggesting that gliclazide's action on endothelium-dependent vasodilation is mediated by its antioxidant properties. Thus far, there are no clinical studies that describe the influence of gliclazide on both oxidative status and NO-mediated vasodilation. We therefore evaluated the effects of gliclazide on plasma lipid peroxides, plasma total radical trapping antioxidant parameter (TRAP), and NO-mediated vasodilation assessed by blood pressure modifications following intravenous L-arginine in 30 subjects with Type 2 diabetes mellitus. The patients received glibenclamide (n=15) or gliclazide (n=15) in a 12-week, randomized, observer-blinded, parallel study, and were studied pre- and post-treatment. At 12 weeks, gliclazide-treated patients had lower plasma lipid peroxides (13.3+/-3.8 vs. 19.2+/-4.3 micromol/l; P=.0001, respectively) and higher plasma TRAP (1155.6+/-143.0 vs. 957.7+/-104.3 micromol/l; P=.0001, respectively) than the glibenclamide-treated patients. Gliclazide, but not glibenclamide, significantly reduced the systolic and diastolic blood pressure (P=.0199 and P=.00199, respectively, two-way repeated-measures analysis of variance) in response to intravenous L-arginine. In conclusion, our results demonstrate that glicazide treatment improves both antioxidant status and NO-mediated vasodilation in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Gliclazida/farmacologia , Glibureto/farmacologia , Adulto , Idoso , Diabetes Mellitus Tipo 2/tratamento farmacológico , Gliclazida/uso terapêutico , Glibureto/uso terapêutico , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Método Simples-Cego , Vasodilatação/efeitos dos fármacos
9.
Methods Inf Med ; 39(1): 44-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10786069

RESUMO

Patient care management provided by healthcare organizations is complex, involving many different care providers. The information exchange between providers concerns a varying and considerable number of actors and a high transmission load. Based on models, used to characterize specific features of work processes, we propose a new method able to analyze and represent clinical communications inside hospitals. Software has been developed, providing tools for storing and retrieving information resulting from clinical communications. The method, together with data collected in actual situations, may constitute useful tools for health information systems developers.


Assuntos
Redes de Comunicação de Computadores , Sistemas de Comunicação no Hospital , Sistemas Computadorizados de Registros Médicos , Sistemas Computacionais , Sistemas de Gerenciamento de Base de Dados , Humanos , Software
10.
Comput Methods Programs Biomed ; 62(1): 59-68, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10699686

RESUMO

This paper is focused on a system for the release and distribution of messages and services among hospital units, which extends hospital information systems features in the field of communication and supports hospital organisation to fulfil healthcare commitments.


Assuntos
Sistemas de Informação Hospitalar , Redes Neurais de Computação , Comunicação , Atenção à Saúde , Humanos
14.
Monogr Soc Res Child Dev ; 45(1): 1-78, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6993920

RESUMO

The development of an instrument--the Metaphoric Triads Task (MTT)--for the assessment of metaphoric comprehension is described. In the tradition of earlier cognitive-style research, a visual triad format was adopted that offered three possible pairings of pictorial stimuli, one of which was metaphorical in character. A subject's score reflects the number of metaphoric pairings formed (with appropriate metaphoric explanations) across all of the triads of the task. Data are reported for 12 samples of subjects (ranging from 7 1/2 to 28 years of age) who responded to the MTT in a diverse array of studies. Internal analyses of the MTT yielded satisfactory reliabilities (interjudge and internal consistency) and item-sum correlations. Sex differences were negligible, but progressive improvement in MTT score with age was noted. At the same time, a slight modification of the MTT triad format generated performance levels from younger children that approximated those of children 1--3 years older who had taken the MTT in its standard form. Higher MTT scores were generally obtained by those subjects who attempted more pairings, spent more time at the task, and chose the metaphoric pair as "best" among the alternative pairing possibilities. Correlations of MTT performance with standardized tests of intellective aptitudes and achievements were inconsistent across samples and between the sexes within samples. In contrast, MTT scores were quite consistently related to solving difficult analogies, generating high-quality responses to divergent-thinking tasks, and manifesting broad categorizing and physiognomic sensitivity. Significant correlations between the MTT and a set of verbal metaphoric triads offered convergent validational evidence suggestive of a general metaphoric style. Some relation was found between MTT performance and teacher ratings of figurative language appreciation and esthetic sensitivity, though it appeared that these might be mediated by the teachers' estimate of the child's overall capability. Finally, three experimental training studies were carried out. A requirement of exhaustive pairing and informative feedback on pretest items significantly enhanced the MTT performance of the younger children. The provision of appropriate verbal labels for each picture in a triad also significantly enhanced performance by insuring that children's encoding of the pictures was consistent with the metaphoric linkage in each item.


Assuntos
Desenvolvimento Infantil , Cognição , Individualidade , Testes Psicológicos , Percepção Visual , Adolescente , Adulto , Fatores Etários , Associação , Criança , Feminino , Humanos , Masculino , Testes Psicológicos/métodos , Fatores Sexuais
15.
Lancet ; 348(9032): 926-8, 1996 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-8843812

RESUMO

BACKGROUND: The cows' milk hypothesis for the cause of insulin-dependent diabetes (IDDM) is based on the concept that early consumption of cows' milk may expose the immune system to a foreign protein possessing immunological cross-reactivity with an antigen present on pancreatic beta-cells. METHODS: We measured in-vitro peripheral lymphocyte response to beta casein, a protein in cows' milk, in 47 patients with recent-onset IDDM, in 36 healthy people and, to test disease specificity, in 10 patients with autoimmune thyroid disease. Other antigens tested for were bovine serum albumin, purified protein derivative, human serum albumin, and phytohaemagglutinin. RESULTS: Specific proliferation of T lymphocytes with bovine beta casein was seen in patients with IDDM (mean [SD] age 18.7 [9]) with a significant difference in mean stimulation index (SI) versus healthy people (p < 0.00001) or patients with autoimmune thyroid disease (p < 0.002). 24 of 47 (51.1%) patients with IDDM versus 0/10 patients with thyroid disease and 1/36 (2.7%) healthy people had a positive response to beta casein defined as a SI above the mean value +2 SD of healthy people (p < 0.00001). No significant differences were observed between the groups of subjects with respect to other antigens tested. INTERPRETATION: The association between IDDM and early consumption of cows' milk may be explained by the generation of a specific immune response to beta casein. Exposure to cows' milk triggers a cellular and humoral anti-beta casein immune response which may cross-react with a beta-cell antigen. It is of interest that sequence homologies exist between beta casein and several beta-cell molecules.


Assuntos
Caseínas/imunologia , Diabetes Mellitus Tipo 1/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Animais , Autoimunidade , Divisão Celular , Diabetes Mellitus Tipo 1/etiologia , Feminino , Humanos , Imunidade Celular , Masculino , Doenças da Glândula Tireoide/imunologia
16.
Diabet Med ; 19(9): 752-7, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12207812

RESUMO

AIMS: To evaluate the effects of gliclazide on oxidative status and vascular response to systemic administration of L-arginine, the natural precursor of nitric oxide (NO), in Type 2 diabetic patients. METHODS: Thirty Type 2 diabetic patients received glibenclamide (n = 15) or gliclazide (n = 15) in a 12-week, randomized, observer-blinded, parallel study. Plasma lipid peroxides, total radical-trapping anti-oxidant parameter (TRAP), and blood pressure responses to an intravenous bolus of L-arginine were measured pre- and post-treatment. RESULTS: At 12 weeks, gliclazide patients had lower plasma lipid peroxides (13.3 +/- 3.8 micro mol/l vs. 19.2 +/- 4.3 micro mol/l; P = 0.0001) and higher plasma TRAP (1155.6 +/- 143.0 micro mol/l vs. 957.7 +/- 104.3 micro mol/l; P = 0.0001) than the glibenclamide patients. Gliclazide but not glibenclamide significantly reduced systolic and diastolic blood pressure (P = 0.0199 and P = 0.00199, respectively, two-way repeated measures analysis of variance) in response to intravenous L-arginine. CONCLUSIONS: Gliclazide reduces oxidative stress in Type 2 diabetic patients by improving plasma anti-oxidant status. This effect is associated with enhanced NO-mediated vasodilation.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Gliclazida/uso terapêutico , Hipoglicemiantes/uso terapêutico , Adulto , Idoso , Antioxidantes/análise , Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Radicais Livres/sangue , Glibureto/uso terapêutico , Humanos , Injeções Intravenosas , Peróxidos Lipídicos/sangue , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
17.
Diabetologia ; 38(7): 848-52, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7556988

RESUMO

Nicotinamide has been recently introduced, in addition to intensive insulin therapy for patients with recent-onset insulin-dependent diabetes mellitus (IDDM) to protect beta cells from end-stage destruction. However, available data are conflicting. A double blind trial in 56 newly-diagnosed IDDM patients receiving nicotinamide for 12 months at a dose of 25 mg/kg body weight or placebo was designed in order to determine whether this treatment could improve the integrated parameters of metabolic control (insulin dose, glycated haemoglobin and C-peptide secretion) in the year after diagnosis. In addition to nicotinamide or placebo, patients received three to four insulin injections daily to optimize blood glucose levels. Patients treated with nicotinamide or placebo received similar doses of insulin during follow-up and 1 year after diagnosis with comparable glycated haemoglobin levels 6.7 +/- 1.8% nicotinamide vs 7.1 +/- 0.6% placebo). Basal and glucagon stimulated C-peptide secretion detectable at diagnosis were similarly preserved in the course of 12 months follow-up both in nicotinamide and placebo treated patients. No adverse effects were observed in patients receiving nicotinamide. When age at diagnosis was taken into account, nicotinamide treated older patients ( > 15 years of age) showed significantly higher stimulated C-peptide secretion than placebo treated patients (p < 0.02). These results suggest that nicotinamide can preserve and improve stimulated beta-cell function only in patients diagnosed after puberty.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Niacinamida/uso terapêutico , Adolescente , Adulto , Fatores Etários , Análise de Variância , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Peptídeo C/sangue , Criança , Pré-Escolar , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/efeitos adversos , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/patologia , Ilhotas Pancreáticas/fisiopatologia , Masculino , Niacinamida/efeitos adversos , Placebos , Fatores de Tempo
18.
Eur J Immunol ; 28(11): 3552-63, 1998 11.
Artigo em Inglês | MEDLINE | ID: mdl-9842898

RESUMO

In this study, T or NK cell clones used as antigen-presenting cells (T- or NK-APC) were shown to be significantly less efficient than professional APC in inducing Th1 and Th2 cytokines by antigen-specific T cell clones. This phenomenon was not related to a limited engagement of TCR by T-APC, since comparable thresholds of TCR down-regulation were shown when antigen was presented by either T-APC or professional APC. Rather, the stimulatory T-APC weakness was due to their inability, because they are CD40-, to provide the appropriate co-stimuli to responder T cells both indirectly via IL-12, and partially via direct CD40L triggering on T cells. Indeed, the simultaneous addition of IL-12 and reagents directly engaging CD40L on responder T cells restored T cell cytokine synthesis when antigen was presented by T-APC. In addition, either IL-12 production or blocking of T cell cytokine synthesis by anti-IL-12 p75 antibodies was evident only when professional APC were used in our antigen-specific system. The down-regulation of cytokine synthesis in the system of T-T cell presentation could represent a novel mechanism of immune regulation, which may intervene to switch off detrimental Th1- or Th2-mediated responses induced by antigen presentation among activated T cells infiltrating inflamed tissues.


Assuntos
Células Apresentadoras de Antígenos/fisiologia , Antígenos CD40/fisiologia , Citocinas/biossíntese , Ativação Linfocitária , Glicoproteínas de Membrana/fisiologia , Células Th1/fisiologia , Células Th2/fisiologia , Antígenos CD/fisiologia , Antígeno B7-1/fisiologia , Antígeno B7-2 , Ligante de CD40 , Células Cultivadas , Humanos , Interleucina-12/farmacologia , Receptores de Antígenos de Linfócitos T/fisiologia
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