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1.
Front Immunol ; 14: 1110544, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37026004

RESUMO

Introduction: In pancreatic islet transplantation, the exact contribution of human leukocyte antigen (HLA) matching to graft survival remains unclear. Islets may be exposed to allogenic rejection but also the recurrence of type 1 diabetes (T1D). We evaluated the HLA-DR matching, including the impact of diabetogenic HLA-DR3 or HLA-DR4 matches. Methods: We retrospectively examined the HLA profile in 965 transplant recipients and 2327 islet donors. The study population was obtained from patients enrolled in the Collaborative Islet Transplant Registry. We then identified 87 recipients who received a single-islet infusion. Islet-kidney recipients, 2nd islet infusion, and patients with missing data were excluded from the analysis (n=878). Results: HLA-DR3 and HLA-DR4 were present in 29.7% and 32.6% of T1D recipients and 11.6% and 15.8% of the donors, respectively. We identified 52 T1D islet recipients mismatched for HLA-DR (group A), 11 with 1 or 2 HLA-DR-matches but excluding HLA-DR3 and HLA- DR4 (group B), and 24 matched for HLA-DR3 or HLA-DR4 (group C). Insulin-independence was maintained in a significantly higher percentage of group B recipients from year one through five post-transplantation (p<0.01). At five-year post-transplantation, 78% of group B was insulin-independent compared to 24% (group A) and 35% (group C). Insulin-independence correlated with significantly better glycemic control (HbA1c <7%), fasting blood glucose, and reduced severe hypoglycemic events. Matching HLA-A-B-DR (≥3) independently of HLA- DR3 or HLA-DR4 matching did not improve graft survival. Conclusion: This study suggests that matching HLA-DR but excluding the diabetogenic HLA-DR3 and/or 4 is a significant predictor for long-term islet survival.


Assuntos
Diabetes Mellitus Tipo 1 , Teste de Histocompatibilidade , Transplante das Ilhotas Pancreáticas , Humanos , Antígeno HLA-DR3 , Antígeno HLA-DR4/análise , Insulina , Estudos Retrospectivos
2.
Oral Health Prev Dent ; 13(5): 449-56, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26106646

RESUMO

PURPOSE: To investigate possible association between the transmission of mutans streptococci and sharing the immune system component Human Leucocyte Antigen (HLA) class II in mother-child pairs. MATERIAL AND METHODS: Plaque samples from 43 mother-child pairs were cultivated and screened for mutans streptococci. In 14 pairs where both mother and child harboured the bacteria, the strains were genotyped by Random Amplified Polymorphic DNA and samples were run on PAGE gels. Analysis of genetic identity between mother and child strains was performed with help of software and Dice similarity index. The distribution of HLA of serogroup DR4 (HLA DR4) was studied in relation to maternal transmission and mutans streptococci colonisation in children. The study hypothesis was that in pairs where both mother and child were HLA DR4 positive, transmission of mutans streptococci was more likely. RESULTS: No correlation between the presence of HLA DR4 in mother and child and maternal transmission of mutans streptococci was established. However, the results showed no linkage between mutans streptococci colonisation and HLA DR 4. Of 15 children with mutans streptococci, 12 were HLA DR4 positive. CONCLUSION: The result suggests that presence of HLA DR4 could be a predisposing factor for colonisation with mutans streptococci in children.


Assuntos
Antígenos HLA/análise , Relações Mãe-Filho , Streptococcus mutans/genética , Técnicas Bacteriológicas , Criança , Pré-Escolar , Impressões Digitais de DNA , Placa Dentária/microbiologia , Saúde da Família , Feminino , Genótipo , Antígeno HLA-DR4/análise , Humanos , Técnica de Amplificação ao Acaso de DNA Polimórfico , Streptococcus mutans/classificação
3.
Aliment Pharmacol Ther ; 39(2): 117-24, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24261965

RESUMO

BACKGROUND: Autoimmune hepatitis is an uncommon chronic progressive inflammatory disease of the liver, characterised by hypergammaglobulianemia, circulating autoantibodies, and interface hepatitis histologically. It is traditionally thought to be a disease of young women. However, recent epidemiological and retrospective studies suggest that it might be a disease predominantly of older women. Studies of AIH in elderly patients have been fairly limited. AIM: To investigate the differences in the clinical presentations and the management of AIH in the elderly and the younger patients. METHODS: We conducted a search on MEDLINE (from 1946), PubMed (1946) and EMBASE (1949) through to November 2013 using the terms 'autoimmune hepatitis in the elderly', and the combinations of 'Autoimmune hepatitis' AND the following terms: 'elderly', 'aging', 'older patients', and 'older'. The reference lists of relevant articles were also searched for appropriate studies. RESULTS: A total of 1063 patients were identified with AIH in 10 retrospective studies. The definition of 'elderly' ranged from 60 to 65 years; 264 elderly and 592 younger patients were included for analysis. Elderly, 24.8%, were more likely to present asymptomatically, cirrhotic at presentation and HLA-DR4-positive. They are less likely to be HLA-DR3-positive and to relapse after treatment withdrawal after complete remission. CONCLUSIONS: AIH is an important differential in elderly patients with cirrhosis or abnormal LFTs. Elderly are more likely to be cirrhotic and asymptomatic at presentation. Glucocorticoids use should be readily considered in the elderly patients as the current evidence suggests that they respond well to the therapy, with less relapse after treatment withdrawal.


Assuntos
Hepatite Autoimune/epidemiologia , Cirrose Hepática/epidemiologia , Idoso , Glucocorticoides/uso terapêutico , Antígeno HLA-DR3/análise , Antígeno HLA-DR4/análise , Haplótipos , Hepatite Autoimune/tratamento farmacológico , Hepatite Autoimune/imunologia , Humanos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/imunologia , Testes de Função Hepática , Estudos Retrospectivos
4.
J Clin Endocrinol Metab ; 97(8): E1573-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22723331

RESUMO

BACKGROUND: Autoantibodies to 21-hydroxylase (21OH-AA) precede the onset of autoimmune Addison's disease (AD) and are found in 1.5% of individuals with type 1 diabetes mellitus (T1DM). The greatest genetic risk for both disorders is found in the major histocompatibility complex (MHC), suggesting a common pathophysiology between AD and T1DM. Screening for 21OH-AA in newly diagnosed T1DM patients is a valuable prognostic tool, made stronger when MHC genotype is considered. METHODS: The Type 1 Diabetes Genetics Consortium has collected genotype data in T1DM subjects with tissue-specific autoantibody typing. Genotype and phenotype data in individuals positive and negative for 21OH-AA are compared. RESULTS: Major genetic risk for 21OH-AA is in the MHC haplotypes DRB1*04-DQB1*0302 (primarily DRB1*0404) and DRB1*0301-DQB1*0201. Protective effects in class II MHC haplotypes DRB1*0101-DQB1*0501 and DRB1*0701-DQB1*0202 also were detected. There is no difference in the presence of HLA-B15 and little difference in the presence of HLA-B8 (after class II effects are accounted for) in T1DM patients with 21OH-AA compared with known associations (HLA-B8 positive and HLA-B15 negative) in AD. CONCLUSIONS: In 21OH-AA(+) subjects, genetic risk is found mainly in MHC class II haplotypes DR3 and DR4 but not class I alleles (HLA-B8 or HLA-B15). This suggests a difference between autoantibody formation (class II dependent) and progression to overt disease (class I dependent) in AD.


Assuntos
Autoanticorpos/genética , Diabetes Mellitus Tipo 1/genética , Esteroide 21-Hidroxilase/imunologia , Doença de Addison/etiologia , Doença de Addison/genética , Doença de Addison/imunologia , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/imunologia , Antígeno HLA-B15/análise , Antígeno HLA-B8/análise , Antígeno HLA-DR3/análise , Antígeno HLA-DR4/análise , Cadeias HLA-DRB1/genética , Haplótipos , Humanos , Esteroide 21-Hidroxilase/análise
5.
Cranio ; 29(1): 32-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21370767

RESUMO

The aim of this study was to determine the presence of HLA alleles, specifically HLA-DR alleles, and to correlate them with clinical and radiological features of patients with degenerative processes (DP) of the temporomandibular joint (TMJ). The final goal was to determine which allele can be used to identify patients having more aggressive forms of the articular pathologies. Thirty-two (32) Caucasian patients with DP of the TMJ were included in the study. The SSOP (Luminex Corp., Austin, TX) method was used to determine class II HLA alleles. The presence of HLA-II DR in patients with DP of the TMJ was 98%. The presence of HLA was significantly higher in patients with DP of the TMJ than in healthy subjects (66%) (p=0.003). HLA DR52 was significantly more frequent in patients than in healthy individuals (40.62% vs. 13.79%, p = 0.041). While the percentage of DR11 positive individuals was also higher among patients than among healthy control subjects, the association with DP of the TMJ was not significant (p=0.220). Patients having the DR52 allele had higher deformation or DP. It was concluded that HLA-DR54 and DR11 alleles are associated with a higher susceptibility to DP of the TMJ, and HLA-DR54 and DR52 are associated with a higher severity of DP.


Assuntos
Antígenos HLA-DR/análise , Osteoartrite/imunologia , Transtornos da Articulação Temporomandibular/imunologia , Adulto , Alelos , Suscetibilidade a Doenças/imunologia , Feminino , Antígenos HLA-DR/genética , Subtipos Sorológicos de HLA-DR , Antígeno HLA-DR1/análise , Antígeno HLA-DR4/análise , Humanos , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/patologia , Imageamento por Ressonância Magnética , Masculino , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Osteoartrite/diagnóstico por imagem , Osteoartrite/patologia , Radiografia , Ruptura , Osso Temporal/diagnóstico por imagem , Osso Temporal/patologia , Articulação Temporomandibular/imunologia , Disco da Articulação Temporomandibular/diagnóstico por imagem , Disco da Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/patologia , Adulto Jovem
6.
Clín. investig. arterioscler. (Ed. impr.) ; 19(2): 76-81, mar. 2007. ilus, tab
Artigo em Es | IBECS | ID: ibc-053198

RESUMO

Introducción. Los polimorfismos genéticos están considerados como los nuevos factores de riesgo para la enfermedad coronaria. Dentro de estos genes podría incluirse al complejo mayor de histocompatibilidad, dada la naturaleza inflamatoria de esta patología. El objetivo de este estudio fue conocer si existe asociación entre el complejo mayor de histocompatibilidad y el infarto de miocardio. Métodos. Se realizó la determinación de los antígenos de histocompatibilidad por el método de microlinfocitotoxicidad en 2 pasos modificado para doble fluorescencia, en 60 pacientes masculinos con antecedentes de infarto de miocardio y 142 donantes sanos, y se estudió la relación con algunos factores de riesgo cardiovasculares. Resultados. Se encontró asociación positiva con los antígenos DR4 (odds ratio [OR] = 3,75; p < 0,025; intervalo de confianza [IC] del 95%, 0,60-2,45) y B8 (OR = 4,37; p < 0,025; IC del 95%, 1,69-3,11) para el infarto de miocardio en comparación con los controles. El antígeno B15 (1,66 frente al 16,66%, p < 0,001; OR = 0,14; p < 0,007; IC del 95%, 0,06-0,63) resultó el menos frecuente en el grupo de pacientes, pudiendo ser útil como marcador de protección. Asimismo, la frecuencia de los haplotipos B8-DR4 (1,2 frente al 9,0%, p < 0,001; OR = 7,50; p < 0,0003; IC del 95%, 2,15-4,17) y B8-DR3 (8,5 frente al 2,3%, p < 0,001; OR = 3,70; p < 0,004; IC del 95%, 2,50-5,12) fue significativamente mayor. Los pacientes DR4 positivos mostraron mayor predisposición para desarrollar múltiples infartos, mientras que los B8 tuvieron mayores antecedentes familiares de cardiopatía isquémica, sin que se encontraran diferencias significativas con los otros factores de riesgo estudiados. Conclusiones. Se encontró asociación entre el sistema mayor de histocompatibilidad y el infarto de miocardio, así como evidencias sobre la posible naturaleza autoinmune de dicho episodio (AU)


Introduction. Genetic polymorphisms have recently been identified as a risk factor for coronary heart disease. Because of the inflammatory nature of this disease, major histocompatibility complex may be included among these genes. The aim of this study was to investigate whether major histocompatibility complex is involved in conferring resistance or susceptibility to myocardial infarction. Methods. Selected human leukocyte antigens (HLA) were studied by the classical two-step microlymphocytotoxicity assay modified for double staining in 60 male patients with a history of myocardial infarction and 142 healthy donors. Several risk factors were analyzed. Results. Positive associations with HLA-DR4 (odds ratio [OR] = 3.75; p < 0.025; 95% confidence interval [CI], 0.60-2.45) and B8 (OR = 4.37; p < 0.025; 95% CI, 1.69-3.11) antigens were found for myocardial infarction compared with healthy controls. The frequency of HLA-B15 antigen was lower in the patient group (1.66% vs. 16.66%, p < 0.001; OR = 0.14; p < 0.007; 95% CI, 0.06-0.63), which would suggest that this antigen is probably a protective factor against myocardial infarction. The frequency of haplotypes B8-DR4 (1.2% vs. 9.0, p < 0.001; OR = 7.50; p < 0.0003; 95% CI, 2.15-4.17) and B8-DR3 (8.5% vs. 2.3%, p < 0.001; OR = 3.70; p < 0.004; 95% CI, 2.50-5.12) was significantly increased in the patient group. DR4-positive patients showed a strong predisposition to developing multiple infarctions, while HLA-B8 positive patients more frequently had a familial history of coronary heart disease. No significant differences were observed between the presence of HLA-DR4 and B8 and the risk factors analyzed. Conclusions. An association was found between major histocompatibility complex and myocardial infarction, as well as evidence of the possible autoimmune nature of this event (AU)


Assuntos
Humanos , Antígenos de Histocompatibilidade/análise , Infarto do Miocárdio/fisiopatologia , Complexo Principal de Histocompatibilidade , Antígenos HLA/análise , Estudos de Casos e Controles , Haplótipos , Fatores de Risco , Antígeno HLA-DR4/análise , Autoimunidade , Polimorfismo Genético
7.
Actas Dermosifiliogr ; 97(8): 509-13, 2006 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-17067528

RESUMO

INTRODUCTION: Pemphigus vulgaris (PV) is a rare autoimmune bullous disease that affects the skin and mucosae, characterized by the presence of antibodies against desmoglein 3, that causes acantholisis and formation of intraepidermal blisters. Observation of PV cases in several members of the same family suggests the existence of genetic factors that contribute to susceptibility to suffer the disease. However, very few cases of familial PV have been described. Based on its autoimmune nature, many studies have found an association between PV and the HLA class II allele, specifically with the HLA-DRB1*0402 DQB1*0302 and HLA-DRB1*1401 DQB1*0503 haplotypes that bestows a significant risk of disease. OBJECTIVES: Study of three families with PV. PATIENTS AND METHODS: In this study, we present three families, with a total of 7 patients, diagnosed of familial PV. HLA antigens were determined with the PCR (polymerase chain reaction) technique in several members of these families. RESULTS: All the subjects affected were positive for HLA DR4 and HLA DR14. The fact that different families with PV are associated with identical haplotypes and that healthy siblings of the patients have the same haplotype is of special interest. CONCLUSION: These results support the concept of genetic predisposition in this rare disease.


Assuntos
Pênfigo/genética , Adulto , Idoso , Alelos , Feminino , Predisposição Genética para Doença , Antígenos HLA/análise , Antígenos HLA-DR/análise , Antígeno HLA-DR4/análise , Haplótipos , Humanos , Masculino , Linhagem , Pênfigo Familiar Benigno/genética , Reação em Cadeia da Polimerase
8.
BMC Bioinformatics ; 7 Suppl 5: S7, 2006 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-17254312

RESUMO

BACKGROUND: Pemphigus vulgaris (PV) is a severe autoimmune blistering skin disorder that is strongly associated with major histocompatibility complex class II alleles DRB1*0402 and DQB1*0503. The target antigen of PV, desmoglein 3 (Dsg3), is crucial for initiating T-cell response in early disease. Although a number of T-cell specificities within Dsg3 have been reported, the number is limited and the role of T-cells in the pathogenesis of PV remains poorly understood. We report here a structure-based model for the prediction of peptide binding to DRB1*0402 and DQB1*0503. The scoring functions were rigorously trained, tested and validated using experimentally verified peptide sequences. RESULTS: High predictivity is obtained for both DRB1*0402 (r2 = 0.90, s = 1.20 kJ/mol, q2 = 0.82, s(press) = 1.61 kJ/mol) and DQB1*0503 (r2 = 0.95, s = 1.20 kJ/mol, q2 = 0.75, s(press) = 2.15 kJ/mol) models, compared to experimental data. We investigated the binding patterns of Dsg3 peptides and illustrate the existence of multiple immunodominant epitopes that may be responsible for both disease initiation and propagation in PV. Further analysis reveals that DRB1*0402 and DQB1*0503 may share similar specificities by binding peptides at different binding registers, thus providing a molecular mechanism for the dual HLA association observed in PV. CONCLUSION: Collectively, the results of this study provide interesting new insights into the pathology of PV. This is the first report illustrating high-level of cross-reactivity between both PV-implicated alleles, DRB1*0402 and DQB1*0503, as well as the existence of a potentially large number of T-cell epitopes throughout the entire Dsg3 extracellular domain (ECD) and transmembrane region. Our results reveal that DR4 and DR6 PV may initiate in the ECD and transmembrane region respectively, with implications for immunotherapeutic strategies for the treatment of this autoimmune disease.


Assuntos
Desmogleína 3/imunologia , Epitopos de Linfócito T/análise , Antígeno HLA-DR4/análise , Antígeno HLA-DR6/análise , Modelos Estatísticos , Pênfigo/imunologia , Sequência de Aminoácidos , Biologia Computacional/métodos , Reações Cruzadas , Desmogleína 3/química , Progressão da Doença , Antígenos HLA-DQ/análise , Cadeias beta de HLA-DQ , Antígenos HLA-DR/análise , Cadeias HLA-DRB1 , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia
9.
Biotechnol Bioeng ; 92(4): 485-91, 2005 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-16155952

RESUMO

Microbial protein display technologies have enabled directed molecular evolution of binding and stability properties in numerous protein systems. In particular, dramatic improvements to antibody binding affinity and kinetics have been accomplished using these tools in recent years. Examples of successful application of display technologies to other immunological proteins have been limited to date. Herein, we describe the expression of human class II major histocompatibility complex allele (MHCII) HLA-DR4 on the surface of Saccharomyces cerevisiae as a noncovalently associated heterodimer. The yeast-displayed MHCII is fully native as assessed by binding of conformationally specific monoclonal antibodies; failure of antibodies specific for empty HLA-DR4 to bind yeast-displayed protein indicates antigenic peptide is bound. This report represents the first example of a noncovalent protein dimer displayed on yeast and of successful display of wild-type MHCII. Results further point to the potential for using yeast surface display for engineering and analyzing the antigen binding properties of MHCII.


Assuntos
Anticorpos Monoclonais/química , Expressão Gênica , Antígeno HLA-DR4/análise , Saccharomyces cerevisiae/genética , Anticorpos Monoclonais/imunologia , Antígeno HLA-DR4/biossíntese , Antígeno HLA-DR4/genética , Humanos , Conformação Proteica , Proteínas Recombinantes/análise , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética
10.
Ann Endocrinol (Paris) ; 66(4): 347-54, 2005 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16392185

RESUMO

Cystic fibrosis is an autosomal recessive disorder affecting about 1/3500 case in France. The disease, that affects all epithelia, is responsible for pulmonary tract infections but also pancreas, gut, liver and genital tract abnormalities. It is linked to CFTR gene mutations, inducing unusually high increase of sodium chloride in sweat, used to track down the illness. deltaF508 CFTR mutation, encountered in 70% of cases, is nearly always associated to pancreatic insufficiency with early-onset lung attack. Around 10% of cystic fibrosis cases, whatever the age, are complicated with partially insulinopenic diabetes, favored by pancreatic fibrosis, while one third of patients shows glucose intolerance. After 20 years old, one third of patients suffers from diabetes and one half after 30 years. Diabetes diagnosis is difficult, and requires the fulfillment of oral glucose tolerance test (OGTT). One glycemia greater or equal to 2 g/l, two hours after a 75 g glucose load, established diabetes diagnosis. Indeed, fasting blood glucose and glycated hemoglobin appear as poor diagnosis markers. Despite histological arguments in favor of the mainly mechanical islet disturbances, an increased prevalence of anti-islets auto-antibodies and an increased frequency of HLA DR3/DR4 have been reported in cystic fibrosis population with glucose tolerance troubles. Also, glucose metabolism is influenced by specific factors linked to cystic fibrosis (infection, malnutrition, steroids...). In reason of the silent phase of diabetes, systematic tracking down of diabetes with a yearly OGTT is recommended, all the more so that hyperglycemia appears as a worsening factor of cystic fibrosis. The efficacy of oral anti-diabetic drugs has not been evaluated on large studies. By contrast, some studies argue for insulin therapy as soon as diabetes appears, insulin improving respiratory and nutritional prognosis. In conclusion, the aim of treatment of cystic fibrosis is to prevent the lung function decline by controlling inflammation and infection, to implement endo- and exo-crine pancreas insufficiency, and to improve nutritional status.


Assuntos
Fibrose Cística/complicações , Diabetes Mellitus/etiologia , Adulto , Autoanticorpos/sangue , Fibrose Cística/genética , Fibrose Cística/terapia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Fibrose , Genótipo , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/epidemiologia , Intolerância à Glucose/etiologia , Teste de Tolerância a Glucose , Antígeno HLA-DR3/análise , Antígeno HLA-DR4/análise , Humanos , Ilhotas Pancreáticas/imunologia , Mutação , Pâncreas/patologia , Fenótipo
11.
J Clin Invest ; 114(4): 589-97, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15314696

RESUMO

Children at risk for type 1 diabetes can develop early insulin autoantibodies (IAAs). Many, but not all, of these children subsequently develop multiple islet autoantibodies and diabetes. To determine whether disease progression is reflected by autoantibody maturity, IAA affinity was measured by competitive radiobinding assay in first and subsequent IAA-positive samples from children followed from birth in the BABYDIAB cohort. IAA affinity in first positive samples ranged from less than 10(6) l/mol to more than 10(11) l/mol. High affinity was associated with HLA DRB1*04, young age of IAA appearance, and subsequent progression to multiple islet autoantibodies or type 1 diabetes. IAA affinity in multiple antibody-positive children was on average 100-fold higher than in children who remained single IAA positive or became autoantibody negative. All high-affinity IAAs required conservation of human insulin A chain residues 8-13 and were reactive with proinsulin. In contrast, most lower-affinity IAAs were dependent on COOH-terminal B chain residues and did not bind proinsulin. These data are consistent with the concept that type 1 diabetes is associated with sustained early exposure to (pro)insulin in the context of HLA DR4 and show that high-affinity proinsulin-reactive IAAs identify children with the highest diabetes risk.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Anticorpos Anti-Insulina/análise , Insulina/imunologia , Proinsulina/imunologia , Sequência de Aminoácidos , Autoanticorpos/sangue , Ligação Competitiva , Criança , Pré-Escolar , Estudos de Coortes , Epitopos , Antígeno HLA-DR4/análise , Antígeno HLA-DR4/sangue , Haplótipos , Humanos , Lactente , Insulina/química , Anticorpos Anti-Insulina/metabolismo , Ilhotas Pancreáticas/imunologia , Proinsulina/metabolismo , Estudos Prospectivos , Fatores de Risco
12.
Transplant Proc ; 36(5): 1340-3, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15251327

RESUMO

Renal transplantation is the best treatment of some end-stage renal diseases. Unfortunately, not every transplant is successful due to the rejection or dysfunction of the transplanted kidney. Many cytokines participate in rejection by inducing inflammation or apoptosis. In this study, the expressions of TRAIL, DR4, and DR5 in rejected renal tissue and of serum soluble TRAIL (sTRAIL) in patients with kidney rejection were investigated by immunohistochemical staining and sandwich enzyme-linked immunosorbent assay, respectively. The results showed that the expression of TRAIL, DR4 and DR5, and serum sTRAIL levels were markedly upregulated among renal transplant patients. Since both membrane and soluble forms of TRAIL can induce apoptosis of DR4/DR5-expressing cells via recruiting FADD and caspase 8, elevated TRAIL and its receptors may participate in renal graft rejection.


Assuntos
Antígeno HLA-DR4/análise , Antígeno HLA-DR5/análise , Transplante de Rim/imunologia , Glicoproteínas de Membrana/análise , Fator de Necrose Tumoral alfa/análise , Apoptose , Proteínas Reguladoras de Apoptose , Ensaio de Imunoadsorção Enzimática , Antígeno HLA-DR4/sangue , Antígeno HLA-DR4/genética , Antígeno HLA-DR5/sangue , Antígeno HLA-DR5/genética , Humanos , Transplante de Rim/patologia , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/genética , Valores de Referência , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Necrose Tumoral alfa/genética
14.
Br J Haematol ; 123(3): 449-53, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14617004

RESUMO

T-cell large granular lymphocytic lymphoproliferative disease (T-LGL) is often associated with life-threatening cytopenias. Twenty-five subjects with anaemia and/or neutropenia caused by T-LGL were treated with cyclosporin A (CSA) 5-10 mg/kg/d for at least 3 months. Eighteen patients survived between 35 and 77 months after starting treatment. Fourteen patients [56%; 95% confidence interval (CI) 35-76%] responded to CSA with sustained improvement in the neutrophil count or transfusion independence. Seven had complete normalization of blood counts, and four achieved a durable response only after the addition of erythropoietin. Sustained response required continued low-dose CSA. In a multivariate analysis, HLA-DR4 was highly predictive of CSA responsiveness (odds ratio 18; 95% CI 1.8-184). T-LGL subtype, LGL counts after therapy, lymphocytic marrow infiltration and bone marrow cellularity did not significantly affect the probability of response. We conclude that CSA is effective in inducing haematological responses in HLA-DR4-positive patients and that T-LGL is likely to have an immune pathogenesis.


Assuntos
Ciclosporina/uso terapêutico , Antígeno HLA-DR4/análise , Imunossupressores/uso terapêutico , Leucemia de Células T/tratamento farmacológico , Adulto , Idoso , Biomarcadores/análise , Feminino , Humanos , Leucemia de Células T/imunologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
15.
Med Pediatr Oncol ; 41(6): 502-7, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14595706

RESUMO

BACKGROUND: Current theory on the etiology of Langerhans cell histiocytosis (LCH), formerly Histiocytosis-X, is that abnormality(ies) of the immune system are responsible for dysregulation of Langerhans cells (LC) in patients' lesions. Among the known abnormalities in LCH patients are increased amounts of tumor necrosis factor alpha (TNF-alpha) and other cytokines in the lesions. PROCEDURE: We investigated the human leukocyte antigen (HLA) phenotypes of 29 patients and 37 healthy family members to determine if any haplotypes segregate with the presence or locations of the disease. The lymphocyte subsets for 22 patients and 11 family members were also determined. RESULTS: Patients with single bone, multiple bone, or multi-system LCH had different relative proportions of HLA types. Patients presenting with single bone disease had an especially high frequency of the DR4 type. In this patient group, every Caucasian patient had either Cw7 or DR4. Lymphopenia was documented in patients who had been off therapy as well as those who only had surgical curetage of their lesions. Family members also had low numbers of T lymphocytes. There were fewer mutations of the TNF-alpha promoter in patients than in the general population. CONCLUSIONS: Although there is an increased percentage of LCH patients with DR4 and/or Cw7 there was also an increased prevalence of this antigen as well as lymphopenia among unaffected family members. Additional genetic and/or environmental factors are necessary to explain this association. TNF-alpha promoter mutations are not responsible for the increased production of this cytokine.


Assuntos
Antígenos HLA-C/biossíntese , Antígeno HLA-DR4/biossíntese , Histiocitose de Células de Langerhans/genética , Histiocitose de Células de Langerhans/imunologia , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Criança , Análise Mutacional de DNA , Primers do DNA , Feminino , Antígenos HLA-C/análise , Antígeno HLA-DR4/análise , Histiocitose de Células de Langerhans/patologia , Humanos , Subpopulações de Linfócitos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da Polimerase
16.
Hum Immunol ; 64(9): 874-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12941542

RESUMO

Type 1 diabetes mellitus (T1DM) is an autoimmune disorder in which genetics and environmental factors play a role. Among the environmental factors, viruses (especially Coxsackie virus B [CBV]), and among genetic markers, human leukocyte antigen (HLA) DRB1*04-DQA1*0301-DQB1*0302 (DR4-DQ8) and DRB1*03-DQA1*0501-DQB1*0201 (DR3-DQ2), and major histocompatibility complex class I chain-related gene-A (MICA) alleles 5 and 5.1 have been reported to be associated with T1DM in Caucasians. Sweden ranks third in the world for T1DM incidence. In Sweden, the Linköping region indicates the highest incidence for T1DM. In this study, we analyzed whether antibodies against CBV are increased in DR3, DR4, MICA5, or MICA5.1 positive patients from Linköping (n = 46) and from Swedish population as a whole (n = 298) between the age of 0 and 15 years old. There was no difference in the frequency of antibodies to CBV in patients compared with controls in Linköping (26% vs 23%) or in all of Sweden (26% vs 21%). However, CBV antibodies were increased in DR3, DR3-DR4 (heterozygous), DR3-MICA5.1, and DR3-DR4-MICA5.1 positive compared with DR3, DR3-DR4, DR3-MICA5.1, and DR3-DR4-MICA5.1 negative patients in Linköping (p < 0.05 for all), but not in Swedish population as a whole. Thus, our study suggests that in addition to DR3, MICA5.1 has an influence on the immune response to CBV infection in patients from Linköping.


Assuntos
Anticorpos Antivirais/biossíntese , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/virologia , Enterovirus Humano B/imunologia , Antígeno HLA-DR3/análise , Antígenos de Histocompatibilidade Classe I/análise , Adolescente , Diabetes Mellitus Tipo 1/genética , Infecções por Enterovirus/imunologia , Antígeno HLA-DR4/análise , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Estudos Retrospectivos , Suécia
18.
Ann Rheum Dis ; 62(3): 227-30, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12594107

RESUMO

OBJECTIVE: To investigate whether there is an association between HLA class II and distal interphalangeal osteoarthritis (DIP OA). METHODS: The study group consisted of consecutive patients with and without DIP OA aged between 40 and 70 years. DIP OA was diagnosed by radiology. These patients were referred to an "Early Arthritis Clinic" (EAC) with different types of arthritis at an early stage. Patients with rheumatoid arthritis, systemic lupus erythematosus, spondyloarthropathies, and psoriatic arthritis were excluded for the purpose of this study. DNA typing for HLA-DR and x ray examination of the hands were performed at enrollment in the EAC. To establish whether the study group was representative of the Dutch population, a population based study in Zoetermeer (n=3243) for the prevalence of DIP OA and blood donors in the Leiden area (n=2400) for the HLA-DR antigen frequencies were used as references. RESULTS: Fifty five patients (33%) of the total study group (n=166) had DIP OA. The prevalence of DIP OA and frequency of the HLA-DR alleles were similar to those of the two reference groups. Within the study group an association between DIP OA and HLA-DR2 and DR4 with respectively odds ratios of 2.4 (95% confidence interval (CI) 1.1 to 5.0) and 0.3 (95% CI 0.1 to 0.7) was found. No association was found between other HLA-DR alleles and DIP OA. CONCLUSION: The study group is a representative sample of the Dutch population. The HLA-DR2 allele was more common in patients with DIP OA. Furthermore, an inverse relation was observed between DIP OA and HLA-DR4. The results confirm findings from other investigations implicating HLA-DR2 as a risk factor in the development of DIP OA.


Assuntos
Articulações dos Dedos , Genes MHC da Classe II , Osteoartrite/genética , Adulto , Idoso , Alelos , Feminino , Articulações dos Dedos/diagnóstico por imagem , Antígeno HLA-DR2/análise , Antígeno HLA-DR4/análise , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Razão de Chances , Osteoartrite/diagnóstico por imagem , Osteoartrite/epidemiologia , Prevalência , Estudos Prospectivos , Radiografia
19.
Neurology ; 59(10): 1652-5, 2002 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-12451219

RESUMO

The authors studied the possible association between the presence of a 32-base pair deletion allele in CC chemokine receptor 5 gene [3p21] (CCR5 Delta 32 allele) and the occurrence of MS. The presence of CCR5 Delta 32 homozygotes among patients with MS indicates that the absence of CCR5 did not protect against MS. Moreover, the CCR5 Delta 32 mutation was associated with MS in HLA-DR4-positive Russians (p(corr) < 0.001, odds ratio [OR] = 25.0). The (CCR5 Delta 32,DR4)-positive phenotype was negatively associated with early MS onset (at ages < or = 18 years) (p = 0.0115, OR = 0.1).


Assuntos
Antígeno HLA-DR4/análise , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/genética , Receptores CCR5/genética , Adulto , Idade de Início , Alelos , DNA/genética , Feminino , Deleção de Genes , Frequência do Gene , Genótipo , Humanos , Masculino , Esclerose Múltipla/imunologia , Mutação/genética , Mutação/fisiologia , Fenótipo , Federação Russa/epidemiologia
20.
Diabet Med ; 19(10): 832-5, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12358870

RESUMO

AIMS: We aimed to characterize a cohort of 'atypical' diabetic patients of sub-Saharan African origin and to analyse possible determinants of long-term remission. METHODS: Over 6 years, we studied the clinical and therapeutic profile of 42 consecutive patients undiagnosed or untreated prior to inclusion presenting with cardinal features of diabetes mellitus. We measured insulin secretion and sensitivity at inclusion. Immunogenetic (anti-GAD, anti-ICA and HLA class II) markers of Type 1 diabetes were compared with a 90-non-diabetic unrelated adult African population. RESULTS: Twenty-one ketonuric patients (age 42 +/- 9 (sd) years; body mass index (BMI) 26 +/- 3 kg/m2) were initially insulin-treated (IT), and 21 non-ketonuric patients (age 38 +/- 8 years; BMI 26 +/- 5 kg/m2) had oral and/or diet therapy (NIT). Insulin could be discontinued in 47.6% (10/21) IT with adequate glycaemic control (HbA1c 6.7 +/- 1.3%), while insulin was secondarily started in 38.1% (8/21) NIT in expectation of better control. The initial basal (odds ratio (OR) 9.1, 95% confidence interval (CI) 1.3-64.4) and stimulated C-peptide (OR 8.17, 95% CI 1.5-44.1) were independently associated with remission. Insulin resistance was present in all the groups, more marked in the insulin-treated NIT. Anti-GAD antibodies and ICA were rare, but 38.1% IT vs. 1.1% controls had Type 1 diabetes HLA susceptibility haplotypes (P < 0.001) without significant difference between the subgroups. CONCLUSION: Prolonged discontinuation of insulin is frequent in African diabetic patients initially presenting with signs of insulinopenia. In our patients, long-term insulin therapy was not associated with immunogenetic markers of Type 1 diabetes. The initial measure of insulin secretion seemed a good predictor of long-term remission.


Assuntos
Peptídeo C/análise , Diabetes Mellitus/sangue , Insulina/uso terapêutico , Doença Aguda , Adulto , África Subsaariana , Autoanticorpos/sangue , Diabetes Mellitus/genética , Diabetes Mellitus/imunologia , Esquema de Medicação , Seguimentos , Predisposição Genética para Doença , Antígeno HLA-DR3/análise , Antígeno HLA-DR4/análise , Humanos , Insulina/sangue , Resistência à Insulina , Ilhotas Pancreáticas/imunologia , Modelos Logísticos , Pessoa de Meia-Idade , Indução de Remissão , Fatores de Tempo
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