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1.
Rheumatol Int ; 32(5): 1121-33, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22083610

RESUMO

Uveitis in juvenile idiopathic arthritis (JIA) is frequently associated with the development of complications and visual loss. Topical corticosteroids are the first-choice therapy, and immunosuppression is commonly used. However, treatment has not been standardized. Representatives from the German Ophthalmological Society, Society for Childhood and Adolescent Rheumatology, and the German Society for Rheumatology reached consensus on a standardized treatment strategy according to disease severity in the individual patient. The recommendations were based on a systematic literature analysis in MEDLINE and consensus expert meetings. Evidence and recommendations were graded, and an algorithm for anti-inflammatory treatment and final statements confirmed in a Delphi method. An interdisciplinary, evidence-based treatment guideline for JIA uveitis is presented.


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite Juvenil/complicações , Medicina Baseada em Evidências/normas , Oftalmologia/normas , Reumatologia/normas , Uveíte/tratamento farmacológico , Adolescente , Algoritmos , Anti-Inflamatórios/efeitos adversos , Artrite Juvenil/imunologia , Criança , Comportamento Cooperativo , Técnica Delphi , Alemanha , Humanos , Comunicação Interdisciplinar , Equipe de Assistência ao Paciente , Recidiva , Resultado do Tratamento , Uveíte/diagnóstico , Uveíte/etiologia , Uveíte/imunologia
2.
Klin Padiatr ; 223(6): 386-94, 2011 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22012606

RESUMO

BACKGROUND: Treatment of Juvenile Idiopathic Arthritis (JIA) has improved quality of life in children and adolescents with JIA. Standardisation of care offers the chance to improve the quality of care of those patients. New studies have been published after completion of our last treatment guideline (2007). An updated consensus process is mandatory. METHODS: A systematic literature analysis in PUBMED (key words: juvenile idiopathic (rheumatoid) arthritis, therapy; limits: humans, published in the last 3 years, all child 0-18 years, clinical trial) revealed 17 relevant studies. Studies relating to diagnosis of JIA, Uveitis, vaccination, transition were excluded. Representatives nominated by scientific societies and organisations were invited to consensus conferences which were hosted by a professional moderator. The following societies were invited: Berufsverband der Kinder- und Jugendärzte (BVKJ), Deutsche Gesellschaft für Kinder- und Jugendmedizin (DGKJ), Deutsche Gesellschaft für Rheumatologie (DGRh), Deutsche Ophthalmologische Gesellschaft (DOG), Deutsche Rheuma-Liga Bundesverband, Verein zur Förderung und Unterstützung rheumatologisch erkrankter Kinder und deren Eltern, Vereinigung für Kinderorthopädie, Zentraler Verband der Physiotherapeuten und Krankengymnasten (ZVK). Consensus conferences were each attended by more than 95% of the nominated representatives. Consensus statements were confirmed by nominal group technique and Delphi method. RESULTS AND CONCLUSION: Updated consensus statements regarding drug therapy, symptomatic and surgical management of JIA were compiled and judged strictly by the criteria of Evidence-Based Medicine (EBM).


Assuntos
Artrite Juvenil/terapia , Comportamento Cooperativo , Medicina Baseada em Evidências , Comunicação Interdisciplinar , Adolescente , Anti-Inflamatórios/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Juvenil/diagnóstico , Produtos Biológicos/uso terapêutico , Criança , Pré-Escolar , Terapia Combinada , Alemanha , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Lactente , Terapia Ocupacional , Modalidades de Fisioterapia
3.
Rheumatol Int ; 31(12): 1639-43, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20013264

RESUMO

To report on the differential diagnosis of lyme arthritis and synovial hemangioma due to similar clinical and radiological signs and symptoms. A 15-year-old boy presented at the age of 9 with recurrent rather painless swelling of the right knee. Altogether four episodes lasting for 1-2 weeks each occurred over a period of 18 months before medical advice was sought. Physical examination revealed only a slightly limited range of motion. Living in an endemic area of borreliosis, he reported a tick bite 6 months prior to onset of his symptoms with erythema migrans and was treated for 10 days with amoxicillin. Serology revealed two positive unspecific bands in IgG immunoblot (p41 and 66) with slight positivity for ELISA. Ultrasound revealed synovial thickening and increased fluid. Despite the weak positive serology a diagnosis of lyme arthritis could not be excluded and intravenous antibiotic treatment with ceftriaxone was started. After two further relapses antiinflammatory therapy including intraarticular steroids were introduced with no long lasting effect. A chronical disease developed with alternate periods of swelling and almost complete remission. Ultrasound as well as MRI demonstrated ongoing signs of synovitis, therefore after further progression, a diagnostic arthroscopy was performed showing an inconspicuous knee joint. A second MRI showed focal suprapatellar enhancement and was followed by open arthrotomy revealing a histopathological proven synovial cavernous juxtaarticular hemangioma. To our knowledge, the differential diagnosis of lyme arthritis and synovial hemangioma has not yet been reported despite obvious clinical similarities. In conclusion, in children and adolescents synovial hemangioma has to be considered in differential diagnosis of recurrent knee swelling. Early diagnosis is important to prevent prolonged suffering from chronic joint swelling with probable joint damages, unnecessary treatment procedures and as well school and sports absenteeism.


Assuntos
Hemangioma/patologia , Artropatias/diagnóstico , Joelho/patologia , Doença de Lyme/patologia , Membrana Sinovial/patologia , Adolescente , Antibacterianos/uso terapêutico , Artroscopia , Ceftriaxona/uso terapêutico , Diagnóstico Diferencial , Hemangioma/tratamento farmacológico , Humanos , Artropatias/patologia , Joelho/diagnóstico por imagem , Doença de Lyme/tratamento farmacológico , Imageamento por Ressonância Magnética , Masculino , Amplitude de Movimento Articular , Sinovite/patologia , Ultrassonografia
4.
Z Rheumatol ; 69(6): 561-7, 2010 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-20174926

RESUMO

TNF inhibitors and other biologicals have greatly expanded the therapeutic options for juvenile idiopathic arthritis (JIA). While the efficacy of etanercept and adalimumab has been proven in randomized controlled clinical trials, their long-term safety remains the subject of ongoing investigations. Reports of leukaemia and tumours in children and adolescents treated with etanercept, infliximab and adalimumab have raised questions about an increased risk for malignancies, with lymphoma accounting for the largest group at 50% of all 48 malignancies reported by the FDA.Consequently, TNF inhibitors should be indicated under careful consideration of individual risk factors, such as increased family occurrence of malignancies, or pre-treatment with carcinogenic substances such as cyclophosphamide. This is particularly true for non-approved substances, and non-approved indications, and for combination therapy of TNF inhibitors with immunosuppressive drugs. On the other hand, however, treatment should not be stopped or started in any patient in whom treatment is necessary due to the current knowledge. Adequate patient information, surveillance and documentation of treatment in the registry of the GKJR is strongly recommended.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Artrite Juvenil/tratamento farmacológico , Produtos Biológicos/efeitos adversos , Neoplasias/induzido quimicamente , Sociedades Médicas , Fator de Necrose Tumoral alfa/antagonistas & inibidores , United States Food and Drug Administration , Adolescente , Adulto , Produtos Biológicos/uso terapêutico , Criança , Humanos , Leucemia/induzido quimicamente , Linfoma/induzido quimicamente , Uso Off-Label , Resultado do Tratamento , Estados Unidos , Adulto Jovem
6.
Eur J Pediatr ; 168(1): 1-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18830624

RESUMO

OBJECTIVES: The objectives of this study were to analyse the literature on Sweet's syndrome in childhood focussing on associated diseases and to suggest possible screening procedures for this group of patients. Furthermore, two new patients with Sweet's syndrome are reported. METHODS: A literature search was performed on Pub med using search terms "sweet* syndrome*" and neutrophil* dermatos*. Patients were subdivided into the following groups: classic/idiopathic, paraneoplastic, and parainflammatory Sweet's syndrome. RESULTS: The literature search revealed 64 patients (including our two patients) who were diagnosed with Sweet's syndrome in childhood and adolescence; 27 (42%) patients were categorized as "classic/idiopathic Sweet's syndrome". In 37 patients (58%) chronic associated diseases were reported. Out of these, 21 (33%) patients were categorized as "parainflammatory Sweet's syndrome" including chronic recurrent multifocal osteomyelitis, vasculitis with aortitis, recurrent infections due to immunodeficiencies, arthritis, and systemic lupus erythematosus. Sixteen (25%) patients were categorized as "paraneoplastic Sweet's syndrome" comprising both malignant and premalignant diseases like leukemia, aplastic anaemia, and Fanconi anaemia. As all five (8%) patients treated with drugs (granulocyte-colony stimulating factor, retinoid acid) suffered from malignant, premalignant, or parainflammatory diseases, these patients were categorized according to the underlying disease. Two new children with Sweet's syndrome and associated diseases are presented here, one of them suffering from recurrent infections and trisomy 21, while the other was diagnosed with CNS vasculitis 5(1/2) years after the primary diagnosis. CONCLUSIONS: Sweet's syndrome should be considered in differential diagnosis of prolonged fever with cutaneous involvement. As most cases of pediatric Sweet's syndrome are associated with other diseases we suggest careful screening and monitoring of these patients especially concerning malignant/premalignant diseases, immunodeficiencies, cardiovascular involvement, autoimmune diseases, and drug associations.


Assuntos
Febre/diagnóstico , Febre/metabolismo , Programas de Rastreamento/métodos , Neutrófilos/metabolismo , Dermatopatias/diagnóstico , Dermatopatias/metabolismo , Síndrome de Sweet/epidemiologia , Síndrome de Sweet/fisiopatologia , Doença Aguda , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Imunoglobulinas/sangue , Lactente , Masculino , Neutropenia/diagnóstico , Neutrófilos/patologia , Índice de Gravidade de Doença , Dermatopatias/patologia , Síndrome de Sweet/diagnóstico
8.
Gait Posture ; 25(4): 615-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16905321

RESUMO

BACKGROUND: The knowledge of limb segment masses is critical for the calculation of joint torques. Several methods for segment mass estimation have been described in the literature. They are either inaccurate or not applicable to the limb segments of children. Therefore, we developed a new cylinder brick model (CBM) to estimate segment mass in children. METHODS: The aim of this study was to compare CBM and a model based on a polynomial regression equation (PRE) to volume measurement obtained by the water displacement method (WDM). We examined forearms, hands, lower legs, and feet of 121 children using CBM, PRE, and WDM. The differences between CBM and WDM or PRE and WDM were calculated and compared using a Bland-Altman plot of differences. FINDINGS: Absolute limb segment mass measured by WDM ranged from 0.16+/-0.04 kg for hands in girls 5-6 years old, up to 2.72+/-1.03 kg for legs in girls 11-12 years old. The differences of normalised segment masses ranged from 0.0002+/-0.0021 to 0.0011+/-0.0036 for CBM-WDM and from 0.0023+/-0.0041 to 0.0127+/-0.036 for PRE-WDM (values are mean+/-2 S.D.). The CBM showed better agreement with WDM than PRE for all limb segments in girls and boys. INTERPRETATION: CBM is accurate and superior to PRE for the estimation of individual limb segment mass of children. Therefore, CBM is a practical and useful tool for the analysis of kinetic parameters and the calculation of resulting forces to assess joint functionality in children.


Assuntos
Antropometria/métodos , Extremidades/anatomia & histologia , Modelos Biológicos , Adolescente , Criança , Pré-Escolar , Extremidades/fisiologia , Feminino , Humanos , Masculino , Análise de Regressão , Caracteres Sexuais , Torque
9.
Z Rheumatol ; 65(4): 315-22, 324-6, 2006 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-16710651

RESUMO

Rheumatic diseases in childhood and adolescence differ from those of adulthood according to type, manifestation, treatment and course. A specialized therapy, starting as early as possible, improves the prognosis, can prevent long-term damage and saves the costs of long-term care. Only a specialized pediatric care system can guarantee optimum quality of the processes involved and the results for rheumatology in childhood and adolescence within a global financial system. This requires adequate structural quality of the specialized clinics and departments for pediatric rheumatology. The management of rheumatic diseases in childhood and adolescence is comprehensive and requires a multidisciplinary, specialized and engaged team which can cover the whole spectrum of rheumatic diseases with their various age-dependent aspects. In order to guarantee an adequate, cost-efficient routine, a specialized center which concentrates on inpatient care should treat at least 300 patients with pediatric rheumatic diseases per year. The diagnoses should be divided among the various disease categories with at least 70% of them involving inflammatory rheumatic diseases. For the inpatient care of small children, an accompanying person (parent) is necessary, requiring adequate structures and services. Patient rooms as well as diagnostic (radiography, sonography, etc.) and therapeutic services (physiotherapy, occupational therapy, pool, etc.) must be adequate for small children and school children as well as adolescents. Suitable mother-child units must also be provided and a school for patients is required within the clinic. A pediatric rheumatologist must be available 24 h a day, and it must be possible to reach other specialists within a short time. For painful therapeutic procedures, age-appropriate pain management is obligatory. A continuous adjustment of these recommendations to changing conditions in health politics is intended.


Assuntos
Departamentos Hospitalares/normas , Arquitetura Hospitalar/estatística & dados numéricos , Hospitais Pediátricos/normas , Hospitais Especializados/normas , Equipe de Assistência ao Paciente/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Doenças Reumáticas/terapia , Adolescente , Criança , Análise Custo-Benefício/normas , Diagnóstico Precoce , Alemanha , Necessidades e Demandas de Serviços de Saúde/normas , Humanos , Avaliação de Resultados em Cuidados de Saúde/normas , Doenças Reumáticas/diagnóstico , Especialização/normas
10.
Rheumatology (Oxford) ; 45(9): 1125-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16510525

RESUMO

OBJECTIVE: In children with juvenile idiopathic arthritis (JIA), alterations of the skeletal system have been described. The aim of this cross-sectional study was to evaluate a phalangeal bone ultrasound device in the assessment of the skeletal status in children with active JIA. METHODS: In 49 children with oligoarticular, polyarticular or systemic JIA, the speed of an ultrasound signal (Ad-SOS) through the phalanges of the dominant hand was measured using the Igea 1200. RESULTS: Children in all subgroups were significantly smaller than those in the reference population, but there were no significant deficits in Ad-SOS. The finger width was reduced only in patients with polyarticular JIA. The Ad-SOS correlated highly with height, but no correlation between the finger width and Ad-SOS, and no correlation between the standard deviation scores of body height and Ad-SOS were seen. CONCLUSIONS: Phalangeal ultrasound is strongly dependent on body and therefore bone size, but other parameters of bone and soft tissues influence the measurements as well. It is not possible to differentiate as to which extent the various components of bone and soft tissue influence the measurement results. Ultrasound might therefore be of limited value in the assessment or screening of the skeletal system in children with JIA.


Assuntos
Artrite Juvenil/diagnóstico por imagem , Falanges dos Dedos da Mão/diagnóstico por imagem , Adolescente , Estatura , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estatísticas não Paramétricas , Tomografia Computadorizada por Raios X , Ultrassonografia
11.
Clin Exp Immunol ; 137(3): 578-83, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15320909

RESUMO

Common variable immunodeficiency (CVID) is a heterogeneous immunodeficiency that is accompanied by granulomatous lesions in 5-10% of cases. Why some patients develop granulomatous disease remains unclear. Here we describe a 12-year-old previously healthy girl who presented with pancytopenia and granulomatous lymphoproliferation subsequent to infection with Toxoplasma gondii. Loosely arranged non-fibrosing granulomas were observed in the liver, lymph nodes and lung, but no Toxoplasma tachyzoites could be demonstrated and polymerase chain reaction (PCR) and culture were negative for Toxoplasma and a wide range of other pathogens. While the patient had a normal peripheral B cell status at presentation, the development of CVID could be observed during the following months, leading to a loss of memory B cells. This was accompanied by an increasingly activated CD4(+) T cell compartment and high serum levels of angiotensin-converting enzyme (ACE), tumour necrosis factor (TNF) and sCD25. Steroid therapy reduced pancytopenia, granulomatous lymphoproliferation and cytokine elevations, but did not improve the B cell status. This is the first report of an association of Toxoplasma infection with granulomatous CVID and provides one of the rare examples where the onset of CVID could be documented subsequent to an infectious disease.


Assuntos
Imunodeficiência de Variável Comum/parasitologia , Granulomatose Linfomatoide/parasitologia , Toxoplasmose/imunologia , Doença Aguda , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Criança , Imunodeficiência de Variável Comum/imunologia , Feminino , Humanos , Imuno-Histoquímica , Fígado/imunologia , Pulmão/imunologia , Linfonodos/imunologia , Ativação Linfocitária , Contagem de Linfócitos , Granulomatose Linfomatoide/imunologia
12.
Clin Exp Rheumatol ; 21(2): 257-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12747287

RESUMO

OBJECTIVE: In the oligoarticular subgroup of juvenile idiopathic arthritis, a strong association has been found with the expression of human leukocyte antigen class II molecules HLA-DQA1 *0401-DQB1*0402 and DQA1*0501-DQB1*0301, whereas DQA1*0501-DQB1*0201 is neutral and DQA1 *0201-DQB1*0201 protective. A presentation of different peptides by these DQ alleles would support their role in the disease process. METHODS: Using a synthetic nonapeptide library, a peptide binding motif was determined for the associated DQA1*0501-DQB1*0301 molecule and compared to the neutral and the protective DQ molecules. RESULTS: A differential motif for the three molecules could be deduced, suggesting that peptides preferentially binding to the associated vs. the neutral/protective DQ-molecules are mutually exclusive. CONCLUSION: These results imply a role for differential peptide presentation in the pathogenesis of oligoarthritic JIA. The search for peptides initiating the disease process might be facilitated which could then lead to therapeutical interventions.


Assuntos
Artrite Juvenil/metabolismo , Antígenos HLA-DQ/imunologia , Biblioteca de Peptídeos , Peptídeos/metabolismo , Artrite Juvenil/imunologia , Artrite Juvenil/fisiopatologia , Humanos , Peptídeos/imunologia
14.
J Infect Dis ; 184(10): 1328-30, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11679924

RESUMO

Prednisolone slows the loss of CD4 T cells in individuals with human immunodeficiency virus (HIV) disease and inhibits antigen-induced apoptosis of recently HIV-infected CD4 cells in vitro. This study investigated whether dexamethasone inhibits the ability of macrophages to delete CD4 T cells via anti-CD4 antibody or immune-complexed HIV envelope protein gp120. Peripheral blood mononuclear cells from HIV-negative persons were incubated with CD4-reactive ch412 monoclonal antibody or with gp120/IgG immune complexes and resident macrophages, with and without dexamethasone. Dexamethasone inhibited CD4 cell deletion in a dose-dependent manner. The deletion of normal CD4 cells by macrophages from HIV-infected patients also was inhibited by dexamethasone. Furthermore, up-regulation of CD95 expression on T cells exposed to anti-CD4 and gp120/IgG, which predisposes T cells to CD95-mediated apoptosis, is inhibited by dexamethasone in a dose-dependent fashion. Dexamethasone inhibits the macrophage-mediated deletion of CD4 lymphocytes in HIV-infected persons.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Infecções por HIV/imunologia , HIV-1 , Macrófagos/efeitos dos fármacos , Adulto , Anticorpos Monoclonais/farmacologia , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Relação Dose-Resposta Imunológica , Proteína gp120 do Envelope de HIV/imunologia , Humanos , Macrófagos/imunologia , Regulação para Cima/efeitos dos fármacos , Receptor fas/imunologia
17.
J Pharmacol Exp Ther ; 288(2): 613-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9918566

RESUMO

Antiproliferative action of different pentacyclic triterpenes has repeatedly been reported, and some lipoxygenase inhibitors have been shown to induce cell death in various cell systems. Acetyl-11-keto-beta-boswellic acid (AKBA) is a pentacyclic triterpene that inhibits 5-lipoxygenase in a selective, enzymedirected, nonredox, and noncompetitive manner. To investigate a possible effect of AKBA on leukemic cell growth, proliferation of HL-60 and CCRF-CEM cells was assayed in the presence of AKBA and a structural analog without effect on 5-lipoxygenase, amyrin. Cell counts and [3H]thymidine incorporation were significantly reduced in a dose-dependent manner in the presence of AKBA (IC50 = 30 microM) but not amyrin. An additive effect of AKBA with the crosslinking of the CD95 receptor was also observed. Flow cytometric analysis of propidium iodide-stained cells indicated that the cells underwent apoptosis. This was confirmed by flow cytometric detection of sub-G1 peaks in AKBA-treated cells and by DNA laddering. However, because HL-60 and CCRF-CEM do not express 5-lipoxygenase mRNA constitutively, a mechanism distinct from inhibition of 5-lipoxygenase must account for the effect of AKBA. In a DNA relaxation assay with phiX174RF DNA, AKBA inhibited topoisomerase I from calf thymus at concentrations of >/=10 microM. A semiquantitative cDNA polymerase chain reaction approach was used to estimate the relative level of expression of topoisomerases in both cell lines. The data suggest that induction of apoptosis in HL-60 and CCRF-CEM by AKBA may be due to inhibition of topoisomerase I in these cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , DNA Topoisomerases Tipo II , Inibidores de Lipoxigenase/farmacologia , Inibidores da Topoisomerase I , Triterpenos/farmacologia , Animais , Antígenos de Neoplasias , Araquidonato 5-Lipoxigenase/metabolismo , Divisão Celular/efeitos dos fármacos , DNA Topoisomerases Tipo I/biossíntese , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo II/biossíntese , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Proteínas de Ligação a DNA , Células HL-60/efeitos dos fármacos , Células HL-60/enzimologia , Células HL-60/patologia , Humanos , Isoenzimas/biossíntese , Leucemia de Células T/tratamento farmacológico , Leucemia de Células T/enzimologia , Leucemia de Células T/patologia , Ácido Oleanólico/análogos & derivados , RNA Mensageiro/metabolismo , Ratos , Células Tumorais Cultivadas
18.
Pathobiology ; 67(5-6): 298-301, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10725807

RESUMO

Macrophages (MPhi) affect the T cell response in two mutually exclusive ways: activation or deletion. A MPhi type with T cell activating functions (M1) is able to express and upregulate receptors of the B7 family. IFN-gamma favours this MPhi differentiation pathway via upregulation of CD80 (B7-1) and CD86 (B7-2). The treatment of MPhi with IFN-gamma enhances the alphaCD3-mediated T cell blast transformation and reduces the fraction of deleted T cells. This MPhi type may prevent antibody-mediated T cell destruction by the expression of costimulatory receptors. An IL-10-induced MPhi type (M2) fails to express costimulatory molecules of the B7 family but is an effective cell for T cell destruction. Forming cellular conjugates with T cells through antibodies or immune complexes, M2-MPhi preferentially delete targeted cells in vitro and in vivo.


Assuntos
Apresentação de Antígeno/imunologia , Citotoxicidade Imunológica/imunologia , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Linfócitos T/imunologia , Anticorpos Monoclonais/farmacologia , Complexo CD3/imunologia , Sobrevivência Celular , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Citometria de Fluxo , Humanos , Interferon gama/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Mitógenos , Testes de Neutralização , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T Citotóxicos , Regulação para Cima
19.
Immunology ; 95(3): 437-42, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9824508

RESUMO

Macrophages are capable of destroying T cells with which they form cellular conjugates. The deletion can be prevented by the simultaneous transmission of costimulatory signals. We show here that T cells with elevated major histocompatibility complex (MHC) class I expression are resistant against macrophage-mediated cytotoxicity. T cells that express the CD45RO isotype, considered memory T cells, exhibit MHC class I antigen at higher density than naive CD45RA T cells and upregulate MHC class I expression promptly when they form cellular conjugates with macrophages. We confirm previous observations that CD45RA T cells are more susceptible to antibody- and macrophage-mediated deletion than memory CD45RO T cells. When MHC class I molecules are masked by specific monoclonal antibody or antibody Fab fragments, CD45RA T cells and CD45RO T cells exhibit equal susceptibility to macrophage cytotoxicity, demonstrating that the difference between CD45RA and CD45RO T cells in their sensitivity to macrophage cytotoxicity is determined by their MHC I expression. Separation of CD4 T cells from CD8 T cells deprives memory CD4 T cells of their resistance against macrophage cytotoxicity, suggesting that memory T cells' resistance against destruction by macrophages is controlled by regulatory T cells.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Antígenos de Histocompatibilidade Classe I/metabolismo , Tolerância Imunológica , Macrófagos/imunologia , Subpopulações de Linfócitos T/imunologia , Anticorpos Monoclonais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Comunicação Celular/imunologia , Técnicas de Cultura de Células , Citometria de Fluxo , Humanos , Antígenos Comuns de Leucócito/análise
20.
Immunology ; 94(3): 331-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9767414

RESUMO

Naive T cells mount a vigorous proliferative response to superantigen (SAg) stimulation in vivo. The proliferative response is followed by a partial deletion of responder T cells. Part of the deletion process has recently been attributed to the action of regulatory cytotoxic T cells that recognize major histocompatibility complex (MHC) class I-associated antigen receptor determinants on the target cell surface. Responder T cells that survived the SAg response were found to be incapable of generating a secondary proliferative response to a SAg challenge. We show here that this 'anergy' is enforced by CD8-positive regulatory suppressive T cells. These regulatory cells inhibit cell division of preactivated T cells but not the Sag response of naive T cells. Regulatory T cells are not generated in the presence of cyclosporin A and, once activated, become inactivated or deleted when restimulated in the presence of this immunosuppressive drug.


Assuntos
Anergia Clonal , Enterotoxinas/farmacologia , Staphylococcus aureus/imunologia , Superantígenos/farmacologia , Linfócitos T/imunologia , Animais , Células Cultivadas , Ciclosporina/farmacologia , Feminino , Citometria de Fluxo , Imunossupressores/farmacologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T/efeitos dos fármacos
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