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1.
Cells ; 10(11)2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34831455

RESUMO

DCP-001 is a cell-based cancer vaccine generated by differentiation and maturation of cells from the human DCOne myeloid leukemic cell line. This results in a vaccine comprising a broad array of endogenous tumor antigens combined with a mature dendritic cell (mDC) costimulatory profile, functioning as a local inflammatory adjuvant when injected into an allogeneic recipient. Intradermal DCP-001 vaccination has been shown to be safe and feasible as a post-remission therapy in acute myeloid leukemia. In the current study, the mode of action of DCP-001 was further characterized by static and dynamic analysis of the interaction between labelled DCP-001 and host antigen-presenting cells (APCs). Direct cell-cell interactions and uptake of DCP-001 cellular content by APCs were shown to depend on DCP-001 cell surface expression of calreticulin and phosphatidylserine, while blockade of CD47 enhanced the process. Injection of DCP-001 in an ex vivo human skin model led to its uptake by activated skin-emigrating DCs. These data suggest that, following intradermal DCP-001 vaccination, local and recruited host APCs capture tumor-associated antigens from the vaccine, become activated and migrate to the draining lymph nodes to subsequently (re)activate tumor-reactive T-cells. The improved uptake of DCP-001 by blocking CD47 rationalizes the possible combination of DCP-001 vaccination with CD47 blocking therapies.


Assuntos
Células Alógenas/imunologia , Antígeno CD47/antagonistas & inibidores , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Fosfatidilserinas/metabolismo , Células Apresentadoras de Antígenos/imunologia , Antígeno CD47/metabolismo , Diferenciação Celular , Membrana Celular/metabolismo , Quimiocinas/metabolismo , Humanos , Inflamação/patologia , Modelos Biológicos , Fagocitose , Fenótipo , Pinocitose , Transdução de Sinais
2.
Eur J Pharm Sci ; 84: 9-17, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26747019

RESUMO

Exposure-response analyses of sugammadex on activated partial thromboplastin time (APTT) and prothrombin time international normalized ratio (PT(INR)) were performed using data from two clinical trials in which subjects were co-treated with anti-coagulants, providing a framework to predict these responses in surgical patients on thromboprophylactic doses of low molecular weight or unfractionated heparin. Sugammadex-mediated increases in APTT and PT(INR) were described with a direct effect model, and this relationship was similar in the presence or absence of anti-coagulant therapy in either healthy volunteers or surgical patients. In surgical patients on thromboprophylactic therapy, model-based predictions showed 13.1% and 22.3% increases in respectively APTT and PT(INR) within 30min after administration of 16mg/kg sugammadex. These increases remain below thresholds seen following treatment with standard anti-coagulant therapy and were predicted to be short-lived paralleling the rapid decline in sugammadex plasma concentrations.


Assuntos
Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Heparina/farmacologia , Modelos Biológicos , gama-Ciclodextrinas/farmacologia , gama-Ciclodextrinas/farmacocinética , Adolescente , Adulto , Idoso , Anticoagulantes/uso terapêutico , Estudos Cross-Over , Método Duplo-Cego , Interações Medicamentosas , Feminino , Heparina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Sugammadex , Trombose/prevenção & controle , Adulto Jovem , gama-Ciclodextrinas/sangue
3.
PLoS One ; 9(9): e98684, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25181348

RESUMO

Prednisolone and other glucocorticoids (GCs) are potent anti-inflammatory drugs, but chronic use is hampered by metabolic side effects. Therefore, there is an urgent medical need for improved GCs that are as effective as classical GCs but have a better safety profile. A well-established model to assess anti-inflammatory efficacy is the chronic collagen-induced arthritis (CIA) model in mice, a model with features resembling rheumatoid arthritis. Models to quantify undesired effects of glucocorticoids on glucose kinetics are less well-established. Recently, we have described a model to quantify basal blood glucose kinetics using stably-labeled glucose. In the present study, we have integrated this blood glucose kinetic model in the CIA model to enable quantification of both efficacy and adverse effects in one animal model. Arthritis scores were decreased after treatment with prednisolone, confirming the anti-inflammatory properties of GCs. Both inflammation and prednisolone induced insulin resistance as insulin secretion was strongly increased whereas blood glucose concentrations and hepatic glucose production were only slightly decreased. This insulin resistance did not directly resulted in hyperglycemia, indicating a highly adaptive compensatory mechanism in these mice. In conclusion, this 'all-in-one' model allows for studying effects of (novel) GC compounds on the development of arthritis and glucose kinetics in a single animal. This integrative model provides a valuable tool for investigating (drug-induced) metabolic dysregulation in an inflammatory setting.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Glicemia/metabolismo , Glucocorticoides/efeitos adversos , Glucocorticoides/farmacologia , Animais , Artrite Experimental/sangue , Modelos Animais de Doenças , Glucocorticoides/uso terapêutico , Cinética , Masculino , Camundongos , Prednisolona/efeitos adversos , Prednisolona/farmacologia , Prednisolona/uso terapêutico
4.
Int J Clin Pharmacol Ther ; 52(8): 631-41, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24800921

RESUMO

OBJECTIVE: To investigate the potential effect of sugammadex on anti-Xa anticoagulantactivity of enoxaparin and the activated partial thromboplastin time (APTT) of unfractionated heparin (UFH). METHODS: This two-part, randomized, double-blind, placebocontrolled, four-period cross-over study was performed in healthy males (18 - 45 years). In each period, subjects received 40 mg enoxaparin (in part 1), 5,000 units UFH (in part 2), or placebo followed by 4 or 16 mg/kg sugammadex, or placebo. Treatments were separated by ≥ 4 days. Primary endpoints were anti-Xa activity and APTT both time-averaged from 3 to 30 minutes post-dose. Geometric mean ratios (GMRs) and their two-sided 90% confidence limits were calculated for anticoagulant plus sugammadex (4 or 16 mg/kg) vs. anticoagulant plus placebo. The pre-specified threshold for a potential effect of clinical relevance was a 90% upper confidence limit (UCL) > 1.50. RESULTS: In part 1 (n = 13), the 90% UCLs were 1.07 and 1.08 for GMRs of anti-Xa activity after dosing with 4 and 16 mg/kg sugammadex, respectively. In part 2 (n = 43), the 90% UCLs for GMRs of APTT were 1.06 and 1.15. Neither sugammadex dose produced a treatment effect that met the pre-specified criterion for potential clinical relevance. Treatments were generally well tolerated. CONCLUSIONS: In healthy subjects, treatment with 4 mg/kg and 16 mg/kg sugammadex did not change either anti-Xa activity or APTT to a clinically meaningful extent following pretreatments with enoxaparin or UFH.


Assuntos
Anticoagulantes/farmacologia , Enoxaparina/farmacologia , Inibidores do Fator Xa , gama-Ciclodextrinas/farmacologia , Adolescente , Adulto , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Interações Medicamentosas , Heparina/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Sugammadex , Adulto Jovem , gama-Ciclodextrinas/administração & dosagem
5.
Int J Clin Pharmacol Ther ; 51(12): 976-85, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24120718

RESUMO

OBJECTIVES: This study evaluated interaction potential between sugammadex and aspirin on platelet aggregation. METHODS: This was a randomized, double-blind, placebo-controlled, four-period crossover study in 26 healthy adult males. Treatments were i.v. placebo, i.v. sugammadex 4 mg/kg, and i.v. placebo/sugammadex with oncedaily oral aspirin 75 mg. Primary objective was to assess interaction between sugammadex and aspirin on platelet aggregation using collagen-induced whole-blood aggregometry. Effects on activated partial thromboplastin time (APTT) and cutaneous bleeding time were also evaluated. Platelet aggregation and APTT were evaluated by geometric mean ratios, using area-under-effect curves 3 - 30 minutes after sugammadex/placebo dosing. Bleeding time ratio was evaluated at 5 minutes post-dosing. Non-inferiority margins were pre-specified via literature review. Type I error was controlled using a hierarchical strategy. RESULTS: Ratio for platelet aggregation for aspirin with sugammadex vs. aspirin alone was 1.01, with lower limit of two-sided 90% CI of 0.91(above non-inferiority margin of 0.75). Ratio for statistical interaction between sugammadex and aspirin on APTT was 1.01, with upper 90% CI of 1.04 (below non-inferiority margin of 1.50), and for sugammadex vs. placebo alone was 1.06, with an upper 90% CI of 1.07 (below non-inferiority margin of 1.50). Ratio for bleeding time for aspirin with sugammadex vs. aspirin plus placebo was 1.20, with upper 90% CI of 1.45 (below non-inferiority margin of 1.50). Sugammadex was generally well tolerated. CONCLUSION: There was no clinically relevant reduction in platelet aggregation with addition of sugammadex 4 mg/kg to aspirin. Pre-determined non-inferiority margins were not exceeded for bleeding time and APTT.


Assuntos
Aspirina/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , gama-Ciclodextrinas/farmacologia , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Interações Medicamentosas , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Sugammadex
6.
PLoS One ; 7(11): e48385, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23152771

RESUMO

Glucocorticoids (GCs) such as prednisolone are potent immunosuppressive drugs but suffer from severe adverse effects, including the induction of insulin resistance. Therefore, development of so-called Selective Glucocorticoid Receptor Modulators (SGRM) is highly desirable. Here we describe a non-steroidal Glucocorticoid Receptor (GR)-selective compound (Org 214007-0) with a binding affinity to GR similar to that of prednisolone. Structural modelling of the GR-Org 214007-0 binding site shows disturbance of the loop between helix 11 and helix 12 of GR, confirmed by partial recruitment of the TIF2-3 peptide. Using various cell lines and primary human cells, we show here that Org 214007-0 acts as a partial GC agonist, since it repressed inflammatory genes and was less effective in induction of metabolic genes. More importantly, in vivo studies in mice indicated that Org 214007-0 retained full efficacy in acute inflammation models as well as in a chronic collagen-induced arthritis (CIA) model. Gene expression profiling of muscle tissue derived from arthritic mice showed a partial activity of Org 214007-0 at an equi-efficacious dosage of prednisolone, with an increased ratio in repression versus induction of genes. Finally, in mice Org 214007-0 did not induce elevated fasting glucose nor the shift in glucose/glycogen balance in the liver seen with an equi-efficacious dose of prednisolone. All together, our data demonstrate that Org 214007-0 is a novel SGRMs with an improved therapeutic index compared to prednisolone. This class of SGRMs can contribute to effective anti-inflammatory therapy with a lower risk for metabolic side effects.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Dibenzazepinas/farmacologia , Receptores de Glucocorticoides/agonistas , Tiadiazóis/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Experimental/genética , Glicemia , Dibenzazepinas/uso terapêutico , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Camundongos , Simulação de Acoplamento Molecular , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Ligação Proteica , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/metabolismo , Tiadiazóis/uso terapêutico
7.
Endocrinology ; 153(8): 3713-23, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22653558

RESUMO

Synthetic glucocorticoids such as prednisolone have potent antiinflammatory actions. Unfortunately, these drugs induce severe adverse effects in patients, many of which resemble features of the metabolic syndrome, such as insulin resistance. In this study, we investigated whether adverse effects of prednisolone on glucose homeostasis are aggravated in mice with compromised insulin sensitivity due to a high-fat diet by applying various methods to analyze changes in insulin sensitivity in mice. C57BL/6J mice were fed a high-fat diet for 6 wk and treated with either prednisolone (10 mg/kg · d) or vehicle for the last 7 d. Insulin sensitivity and blood glucose kinetics were analyzed with state-of-the-art stable isotope procedures in different experimental conditions. Prednisolone treatment aggravated fasting hyperglycemia and hyperinsulinemia caused by high-fat feeding, resulting in a higher homeostatic assessment model of insulin resistance. In addition, prednisolone-treated high-fat diet-fed mice appeared less insulin sensitive by detailed analysis of basal glucose kinetics. Remarkably, using hyperinsulinemic-euglycemic or hyperglycemic clamp techniques, neither hepatic nor peripheral insulin resistance was worsened in the group that was treated with prednisolone. Yet analysis of hepatic glucose metabolism revealed that prednisolone did alter glycogen balance by reducing glycogen synthase flux under hyperinsulinemic as well as hyperglycemic conditions. In addition to elevated insulin levels, prednisolone-treated mice showed a major rise in plasma leptin and fibroblast growth factor 21 levels. Our data indicate that prednisolone-induced adverse effects on glucose metabolism in high-fat diet-fed mice do not reflect impaired insulin sensitivity but may be caused by other changes in the hormonal regulatory network controlling glucose metabolism such as fibroblast growth factor 21 and leptin.


Assuntos
Anti-Inflamatórios/efeitos adversos , Gorduras na Dieta/efeitos adversos , Hiperglicemia/induzido quimicamente , Resistência à Insulina/fisiologia , Prednisolona/efeitos adversos , Animais , Glicemia/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
Pharmacogenomics ; 12(7): 985-98, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21635145

RESUMO

BACKGROUND: Prednisolone and other glucocorticoids (GCs) are potent anti-inflammatory and immunosuppressive drugs. However, prolonged use at a medium or high dose is hampered by side effects of which the metabolic side effects are most evident. Relatively little is known about their effect on gene-expression in vivo, the effect on cell subpopulations and the relation to the efficacy and side effects of GCs. AIM: To identify and compare prednisolone-induced gene signatures in CD4⁺ T lymphocytes and CD14⁺ monocytes derived from healthy volunteers and to link these signatures to underlying biological pathways involved in metabolic adverse effects. MATERIALS & METHODS: Whole-genome expression profiling was performed on CD4⁺ T lymphocytes and CD14⁺ monocytes derived from healthy volunteers treated with prednisolone. Text-mining analyses was used to link genes to pathways involved in metabolic adverse events. RESULTS: Induction of gene-expression was much stronger in CD4⁺ T lymphocytes than in CD14⁺ monocytes with respect to fold changes, but the number of truly cell-specific genes where a strong prednisolone effect in one cell type was accompanied by a total lack of prednisolone effect in the other cell type, was relatively low. Subsequently, a large set of genes was identified with a strong link to metabolic processes, for some of which the association with GCs is novel. CONCLUSION: The identified gene signatures provide new starting points for further study into GC-induced transcriptional regulation in vivo and the mechanisms underlying GC-mediated metabolic side effects.


Assuntos
Anti-Inflamatórios/efeitos adversos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Perfilação da Expressão Gênica , Imunossupressores/efeitos adversos , Monócitos/efeitos dos fármacos , Prednisolona/efeitos adversos , Adulto , Anti-Inflamatórios/administração & dosagem , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/metabolismo , Humanos , Hidrocortisona/sangue , Imunossupressores/administração & dosagem , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Receptores de Lipopolissacarídeos/análise , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Prednisolona/administração & dosagem , Prednisolona/sangue , Adulto Jovem
9.
J Autoimmun ; 36(3-4): 201-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21439785

RESUMO

The purpose of the study was to examine the potential of inhibition of cathepsin S as a treatment for autoimmune diseases. A highly selective cathepsin S inhibitor, CSI-75, was shown to upregulate levels of the cathepsin S substrate, invariant chain Lip10, in vitro as well as in vivo in C57Bl/6 mice after oral administration. Functional activity of the compound was shown by a reduction in the OVA-specific response of OVA-sensitized splenocytes from C57Bl/6 mice as well as from OVA-TCR transgenic mice (DO11.10). Since these studies revealed a selective suppression of the Th1 and Th17 cytokines causing a shift to Th2, CSI-75 was tested in the murine HC-gp39-immunization model. Indeed, CSI-75 specifically reduced the circulating HC-gp39-specific IgG2a in these mice indicating selective inhibition of the Th1 type of response in vivo. The importance of especially the Th1 and Th17 cell subsets in the pathology of autoimmune diseases, renders CatS inhibition a highly interesting potential therapeutic treatment of autoimmune diseases. Therefore, CSI-75 was tested in a murine model of multiple sclerosis (i.e. experimental autoimmune encephalomyelitis (EAE)) in a semi-therapeutic setting (ie. oral treatment after initial sensitization to antigen). Finally, in a murine model with features resembling rheumatoid arthritis (the collagen-induced arthritis (CIA) model), CSI-75 was tested in a therapeutic manner (after disease development). CSI-75 caused a significant reduction in disease score in both disease models, indicating a promising role for CatS inhibitors in the area of therapeutic treatments for autoimmune diseases.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Catepsinas/antagonistas & inibidores , Piperidinas/uso terapêutico , Inibidores de Proteases/uso terapêutico , Piridinas/uso terapêutico , Administração Oral , Animais , Células Apresentadoras de Antígenos/efeitos dos fármacos , Artrite Experimental/tratamento farmacológico , Doenças Autoimunes/imunologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Piperidinas/administração & dosagem , Inibidores de Proteases/administração & dosagem , Piridinas/administração & dosagem , Células Th1/fisiologia
10.
BMC Genomics ; 11: 359, 2010 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-20525385

RESUMO

BACKGROUND: Glucocorticoids (GCs) control expression of a large number of genes via binding to the GC receptor (GR). Transcription may be regulated either by binding of the GR dimer to DNA regulatory elements or by protein-protein interactions of GR monomers with other transcription factors. Although the type of regulation for a number of individual target genes is known, the relative contribution of both mechanisms to the regulation of the entire transcriptional program remains elusive. To study the importance of GR dimerization in the regulation of gene expression, we performed gene expression profiling of livers of prednisolone-treated wild type (WT) and mice that have lost the ability to form GR dimers (GRdim). RESULTS: The GR target genes identified in WT mice were predominantly related to glucose metabolism, the cell cycle, apoptosis and inflammation. In GRdim mice, the level of prednisolone-induced gene expression was significantly reduced compared to WT, but not completely absent. Interestingly, for a set of genes, involved in cell cycle and apoptosis processes and strongly related to Foxo3a and p53, induction by prednisolone was completely abolished in GRdim mice. In contrast, glucose metabolism-related genes were still modestly upregulated in GRdim mice upon prednisolone treatment. Finally, we identified several novel GC-inducible genes from which Fam107a, a putative histone acetyltransferase complex interacting protein, was most strongly dependent on GR dimerization. CONCLUSIONS: This study on prednisolone-induced effects in livers of WT and GRdim mice identified a number of interesting candidate genes and pathways regulated by GR dimers and sheds new light onto the complex transcriptional regulation of liver function by GCs.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Prednisolona/farmacologia , Multimerização Proteica , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Análise por Conglomerados , Feminino , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Genômica , Gluconeogênese/efeitos dos fármacos , Gluconeogênese/genética , Masculino , Camundongos , Estrutura Quaternária de Proteína
11.
Endocrinology ; 151(5): 2171-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20185761

RESUMO

Chronic glucocorticoid use for treatment of inflammatory diseases is accompanied by severe side effects in humans (e.g. hyperglycemia and insulin resistance). The present studies were conducted to characterize consequences of chronic treatment with the synthetic glucocorticoid prednisolone on insulin sensitivity and blood glucose kinetics in mice. Prednisolone treatment increased fasting blood glucose and plasma insulin concentrations, but this apparently reduced insulin sensitivity could not be confirmed in hyperinsulinemic euglycemic clamp studies. Therefore, a novel method to study whole body glucose kinetics was used. This method revealed that prednisolone-treated mice show an increased hepatic glucose production (HGP). The increased HGP was accompanied by elevated plasma insulin concentrations, indicating reduced insulin sensitivity of hepatic glucose metabolism in prednisolone-treated mice. Compared with vehicle, prednisolone-treated mice had lower blood glucose concentrations, higher plasma free fatty acids, and higher plasma fibroblast growth factor-21 concentrations in the fed condition, i.e. mimicking a fasting situation. Next, the effects of 24-h fasting on energy metabolism were studied. Compared with controls, fasted prednisolone-treated mice had higher blood glucose concentrations and lower plasma beta-hydroxybutyrate concentrations. In conclusion, these results indicate that chronic prednisolone treatment reduces insulin sensitivity of HGP, induces a fasting-like phenotype in fed mice, and perturbs the fed-to-fasting transition.


Assuntos
Glucose/metabolismo , Resistência à Insulina , Fígado/efeitos dos fármacos , Prednisolona/farmacologia , Algoritmos , Animais , Glicemia/metabolismo , Ingestão de Alimentos/fisiologia , Metabolismo Energético/efeitos dos fármacos , Jejum/sangue , Jejum/fisiologia , Fatores de Crescimento de Fibroblastos/genética , Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Glucose/farmacocinética , Técnica Clamp de Glucose , Insulina/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PPAR alfa/genética , Distribuição Tecidual/efeitos dos fármacos
12.
Arthritis Res Ther ; 9(4): R71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17645792

RESUMO

We sought to identify an altered peptide ligand (APL) based on the endogenously expressed synovial auto-epitope of human cartilage glycoprotein-39 (HC gp-39) for modulation of cognate, HLA-DR4-restricted T cells. For this purpose we employed a panel of well-characterized T cell hybridomas generated from HC gp-39-immunized HLA-DR4 transgenic mice. The hybridomas all respond to the HC gp-39(263-275) epitope when bound to HLA-DR4(B1*0401) but differ in their fine specificities. First, the major histocompatibility complex (MHC) and T-cell receptor (TCR) contact residues were identified by analysis of single site substituted analogue peptides for HLA-DR4 binding and cognate T cell recognition using both T hybridomas and polyclonal T cells from peptide-immunized HLA-DR4 transgenic mice. Analysis of single site substituted APL by cognate T cells led to identification of Phe265 as the dominant MHC anchor. The amino acids Ala268, Ser269, Glu271 and Thr272 constituted the major TCR contact residues, as substitution at these positions did not affect HLA-DR4(B1*0401) binding but abrogated T cell responses. A structural model for visualisation of TCR recognition was derived. Second, a set of non-classical APLs, modified at the MHC key anchor position but with unaltered TCR contacts, was developed. When these APLs were analysed, a partial TCR agonist was identified and found to modulate the HC gp-39(263-275)-specific, pro-inflammatory response in HLA-DR4 transgenic mice. We identified a non-classical APL by modification of the p1 MHC anchor in a synovial auto-epitope. This APL may qualify for rheumatoid arthritis immunotherapy.


Assuntos
Artrite Reumatoide/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito T/imunologia , Glicoproteínas/imunologia , Antígeno HLA-DR4/imunologia , Linfócitos T/imunologia , Adipocinas , Animais , Modulação Antigênica/imunologia , Artrite Reumatoide/metabolismo , Proteína 1 Semelhante à Quitinase-3 , Epitopos de Linfócito T/metabolismo , Glicoproteínas/metabolismo , Antígeno HLA-DR4/metabolismo , Humanos , Hibridomas , Epitopos Imunodominantes/imunologia , Epitopos Imunodominantes/metabolismo , Lectinas , Camundongos , Camundongos Transgênicos , Linfócitos T/metabolismo
13.
J Reprod Immunol ; 60(1): 71-84, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14568679

RESUMO

One-fifth of all in-vitro fertilization (IVF) patients suffer from idiopathic infertility. A low fertilization rate is one of the most characteristic features of IVF in this group, probably caused by oocyte dysfunction. We speculate that an altered lymphocyte profile in follicular fluid (FF) may affect oocyte function and thus play a role in idiopathic infertility. Therefore, we compared levels of lymphocyte populations present in FF of 11 patients with idiopathic infertility (study group) with 29 patients in the control group, i.e. severe male factor infertility (n=17) or tubal factor infertility (n=12). Triple color flow cytometry was used to discriminate between T cells and NK cell subpopulations. In the idiopathic infertility group, a shift from T to NK cells was observed in FF as compared to the control group, caused mainly by a significant higher level of NK cells--20.3 and 13.6% (P<0.05), respectively. This high level of NK cells was due to a rise of the CD16+CD56dim NK cell subset. In peripheral blood, the NK cell levels showed a similar although not significant trend (P=0.08). As the CD16+CD56dim NK cell subpopulation is known for its cytotoxic properties, this subpopulation may negatively affect folliculogenesis and oocyte maturation, reflected by a diminished fertilization rate in the idiopathic infertility group. An altered lymphocyte profile in FF could therefore influence fertility in these patients.


Assuntos
Antígeno CD56/imunologia , Fertilização in vitro , Líquido Folicular/citologia , Células Matadoras Naturais/imunologia , Receptores de IgG/imunologia , Linfócitos B/química , Linfócitos B/imunologia , Feminino , Citometria de Fluxo , Humanos , Infertilidade/imunologia , Células Matadoras Naturais/química , Masculino , Oócitos/citologia , Oócitos/metabolismo , Linfócitos T/química , Linfócitos T/imunologia
14.
Early Hum Dev ; 66(2): 101-5, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11872314

RESUMO

Pregnancies affected by a neural tube defect show changes in thymus morphology, neonatal and maternal T-cell repertoire. Amniotic fluid levels of soluble human leukocyte antigen G (HLA-G) (an immuno-modulatory protein) were found to be significantly lower as compared to controls. This may reflect a diminished cell-mediated immunity in neural tube defects.


Assuntos
Líquido Amniótico/imunologia , Antígenos HLA/biossíntese , Antígenos de Histocompatibilidade Classe I/biossíntese , Defeitos do Tubo Neural/imunologia , Amniocentese , Líquido Amniótico/química , Feminino , Antígenos HLA/análise , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/análise , Humanos , Defeitos do Tubo Neural/metabolismo , Gravidez
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