Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Am Coll Cardiol ; 73(14): 1811-1823, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30975299

RESUMO

BACKGROUND: In giant cell arteritis, vessel-wall infiltrating CD4 T cells and macrophages form tissue-destructive granulomatous infiltrates, and the artery responds with a maladaptive response to injury, leading to intramural neoangiogenesis, intimal hyperplasia, and luminal occlusion. Lesion-residing T cells receive local signals, which represent potential therapeutic targets. OBJECTIVES: The authors examined how CD28 signaling affects vasculitis induction and maintenance, and which pathogenic processes rely on CD28-mediated T-cell activation. METHODS: Vasculitis was induced by transferring peripheral blood mononuclear cells from giant cell arteritis patients into immunodeficient NSG mice engrafted with human arteries. Human artery-NSG chimeras were treated with anti-CD28 domain antibody or control antibody. Treatment effects and immunosuppressive mechanisms were examined in vivo and in vitro applying tissue transcriptome analysis, immunohistochemistry, flow cytometry, and immunometabolic analysis. RESULTS: Blocking CD28-dependent signaling markedly reduced tissue-infiltrating T cells and effectively suppressed vasculitis. Mechanistic studies implicated CD28 in activating AKT signaling, T-cell proliferation and differentiation of IFN-γ and IL-21-producing effector T cells. Blocking CD28 was immunosuppressive by disrupting T-cell metabolic fitness; specifically, the ability to utilize glucose. Expression of the glucose transporter Glut1 and of glycolytic enzymes as well as mitochondrial oxygen consumption were all highly sensitive to CD28 blockade. Also, induction and maintenance of CD4+CD103+ tissue-resident memory T cells, needed to replenish the vasculitic infiltrates, depended on CD28 signaling. CD28 blockade effectively suppressed vasculitis-associated remodeling of the vessel wall. CONCLUSIONS: CD28 stimulation provides a metabolic signal required for pathogenic effector functions in medium and large vessel vasculitis. Disease-associated glycolytic activity in wall-residing T-cell populations can be therapeutically targeted by blocking CD28 signaling.


Assuntos
Imunidade Adaptativa , Antígenos CD28/imunologia , Linfócitos T CD4-Positivos/metabolismo , Remodelação Vascular/imunologia , Animais , Anticorpos/metabolismo , Proliferação de Células , Quimiotaxia de Leucócito/imunologia , Modelos Animais de Doenças , Arterite de Células Gigantes/imunologia , Humanos , Camundongos , Neovascularização Patológica/imunologia , Neovascularização Patológica/prevenção & controle
2.
ACS Med Chem Lett ; 10(3): 306-311, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30891131

RESUMO

The four members of the Janus family of nonreceptor tyrosine kinases play a significant role in immune function. The JAK family kinase inhibitor, tofacitinib 1, has been approved in the United States for use in rheumatoid arthritis (RA) patients. A number of JAK inhibitors with a variety of JAK family selectivity profiles are currently in clinical trials. Our goal was to identify inhibitors that were functionally selective for JAK1 and JAK3. Compound 22 was prepared with the desired functional selectivity profile, but it suffered from poor absorption related to physical properties. Use of the phosphate prodrug 32 enabled progression to a murine collagen induced arthritis (CIA) model. The demonstration of a robust efficacy in the CIA model suggests that use of phosphate prodrugs may resolve issues with progressing this chemotype for the treatment of autoimmune diseases such as RA.

3.
Front Immunol ; 9: 2728, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30534127

RESUMO

Checkpoint inhibitors target the inhibitory receptors expressed by tumor-infiltrating T cells in order to reinvigorate an anti-tumor immune response. Therefore, understanding T cell composition and phenotype in human tumors is crucial. We analyzed by flow cytometry tumor-infiltrating lymphocytes (TILs) from two independent cohorts of patients with different cancer types, including RCC, lung, and colon cancer. In healthy donors, peripheral T cells are usually either CD4+ or CD8+ with a small percentage of CD4+ CD8+ DP cells (<5%). Compared to several other cancer types, including lung, and colorectal cancers, TILs from about a third of RCC patients showed an increased proportion of DP CD4+CD8+ T cells (>5%, reaching 30-50% of T cells in some patients). These DP T cells have an effector memory phenotype and express CD38, 4-1BB, and HLA-DR, suggesting antigen-driven expansion. In fact, TCR sequencing analysis revealed a high degree of clonality in DP T cells. Additionally, there were high levels of PD-1 and TIM-3 expression on DP T cells, which correlated with higher expression of PD-1 and TIM-3 in conventional single positive CD8 T cells from the same patients. These results suggest that DP T cells could be dysfunctional tumor-specific T cells with the potential to be reactivated by checkpoint inhibitors.


Assuntos
Antígenos de Diferenciação/imunologia , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Carcinoma de Células Renais/imunologia , Neoplasias Renais/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Neoplasias/imunologia , Linfócitos T/imunologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Neoplasias Renais/patologia , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/patologia
4.
Front Immunol ; 9: 1613, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123214

RESUMO

Agents targeting the PD1-PDL1 axis have transformed cancer therapy. Factors that influence clinical response to PD1-PDL1 inhibitors include tumor mutational burden, immune infiltration of the tumor, and local PDL1 expression. To identify peripheral correlates of the anti-tumor immune response in the absence of checkpoint blockade, we performed a retrospective study of circulating T cell subpopulations and matched tumor gene expression in melanoma and non-small cell lung cancer (NSCLC) patients. Notably, both melanoma and NSCLC patients whose tumors exhibited increased inflammatory gene transcripts presented high CD4+ and CD8+ central memory T cell (CM) to effector T cell (Eff) ratios in blood. Consequently, we evaluated CM/Eff T cell ratios in a second cohort of NSCLC. The data showed that high CM/Eff T cell ratios correlated with increased tumor PDL1 expression. Furthermore, of the 22 patients within this NSCLC cohort who received nivolumab, those with high CM/Eff T cell ratios, had longer progression-free survival (PFS) (median survival: 91 vs. 215 days). These findings show that by providing a window into the state of the immune system, peripheral T cell subpopulations inform about the state of the anti-tumor immune response and identify potential blood biomarkers of clinical response to checkpoint inhibitors in melanoma and NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Neoplasias Pulmonares/imunologia , Melanoma/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Subpopulações de Linfócitos T/imunologia , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Intervalo Livre de Progressão , Subpopulações de Linfócitos T/metabolismo
5.
Arthritis Rheumatol ; 70(8): 1331-1342, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29534336

RESUMO

OBJECTIVE: To develop an objective, readily measurable pharmacodynamic biomarker of glucocorticoid (GC) activity. METHODS: Genes modulated by prednisolone were identified from in vitro studies using peripheral blood mononuclear cells from normal healthy volunteers. Using the criteria of a >2-fold change relative to vehicle controls and an adjusted P value cutoff of less than 0.05, 64 up-regulated and 18 down-regulated genes were identified. A composite score of the up-regulated genes was generated using a single-sample gene set enrichment analysis algorithm. RESULTS: GC gene signature expression was significantly elevated in peripheral blood leukocytes from normal healthy volunteers following oral administration of prednisolone. Expression of the signature increased in a dose-dependent manner, peaked at 4 hours postadministration, and returned to baseline levels by 48 hours after dosing. Lower expression was detected in normal healthy volunteers who received a partial GC receptor agonist, which is consistent with the reduced transactivation potential of this compound. In cohorts of patients with systemic lupus erythematosus and patients with rheumatoid arthritis, expression of the GC signature was negatively correlated with the percentages of peripheral blood lymphocytes and positively correlated with peripheral blood neutrophil counts, which is consistent with the known biology of the GC receptor. Expression of the signature largely agreed with reported GC use in these populations, although there was significant interpatient variability within the dose cohorts. CONCLUSION: The GC gene signature identified in this study represents a pharmacodynamic marker of GC exposure.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Leucócitos Mononucleares/efeitos dos fármacos , Prednisolona/administração & dosagem , Administração Oral , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Voluntários Saudáveis , Humanos , Contagem de Leucócitos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/genética , Masculino , Testes Farmacogenômicos , Regulação para Cima/efeitos dos fármacos
6.
Bioorg Med Chem Lett ; 27(14): 3101-3106, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28539220

RESUMO

A series of potent dual JAK1/3 inhibitors have been developed from a moderately selective JAK3 inhibitor. Substitution at the C6 position of the pyrrolopyridazine core with aryl groups provided exceptional biochemical potency against JAK1 and JAK3 while maintaining good selectivity against JAK2 and Tyk2. Translation to in vivo efficacy was observed in a murine model of chronic inflammation. X-ray co-crystal structure determination confirmed the presumed inhibitor binding orientation in JAK3. Efforts to reduce hERG channel inhibition will be described.


Assuntos
Janus Quinase 1/antagonistas & inibidores , Janus Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Piridazinas/química , Pirróis/química , Animais , Sítios de Ligação , Domínio Catalítico , Linhagem Celular , Cristalografia por Raios X , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Inflamação/prevenção & controle , Concentração Inibidora 50 , Janus Quinase 1/metabolismo , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/metabolismo , Janus Quinase 3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Piridazinas/síntese química , Piridazinas/farmacocinética , Pirróis/síntese química , Pirróis/farmacocinética , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , TYK2 Quinase/antagonistas & inibidores , TYK2 Quinase/metabolismo
7.
JCI Insight ; 1(9): e87310, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27699274

RESUMO

Systemic lupus erythematosus (SLE) is a complex systemic autoimmune disease driven by both innate and adaptive immune cells. African Americans tend to present with more severe disease at an earlier age compared with patients of European ancestry. In order to better understand the immunological differences between African American and European American patients, we analyzed the frequencies of B cell subsets and the expression of B cell activation markers from a total of 68 SLE patients and 69 normal healthy volunteers. We found that B cells expressing the activation markers CD86, CD80, PD1, and CD40L, as well as CD19+CD27-IgD- double-negative B cells, were enriched in African American patients vs. patients of European ancestry. In addition to increased expression of CD40L, surface levels of CD40 on B cells were lower, suggesting the engagement of the CD40 pathway. In vitro experiments confirmed that CD40L expressed by B cells could lead to CD40 activation and internalization on adjacent B cells. To conclude, these results indicate that, compared with European American patients, African American SLE patients present with a particularly active B cell component, possibly via the activation of the CD40/CD40L pathway. These data may help guide the development of novel therapies.


Assuntos
Linfócitos B/citologia , Lúpus Eritematoso Sistêmico/etnologia , Afro-Americanos , Antígenos de Superfície/análise , Antígeno B7-2/análise , Antígenos CD40/análise , Ligante de CD40/análise , Humanos , Fenótipo
8.
J Mol Biol ; 428(14): 2860-79, 2016 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-27216500

RESUMO

Current clinical anti-CD40 biologic agents include both antagonist molecules for the treatment of autoimmune diseases and agonist molecules for immuno-oncology, yet the relationship between CD40 epitope and these opposing biological outcomes is not well defined. This report describes the identification of potent antagonist domain antibodies (dAbs) that bind to a novel human CD40-specific epitope that is divergent in the CD40 of nonhuman primates. A similarly selected anti-cynomolgus CD40 dAb recognizing the homologous epitope is also a potent antagonist. Mutagenesis, biochemical, and X-ray crystallography studies demonstrate that the epitope is distinct from that of CD40 agonists. Both the human-specific and cynomolgus-specific molecules remain pure antagonists even when formatted as bivalent Fc-fusion proteins, making this an attractive therapeutic format for targeting hCD40 in autoimmune indications.


Assuntos
Antígenos CD40/imunologia , Epitopos/imunologia , Animais , Doenças Autoimunes/imunologia , Cristalografia por Raios X/métodos , Humanos , Macaca fascicularis
9.
Front Immunol ; 7: 21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26870037

RESUMO

Biological molecules are increasingly becoming a part of the therapeutics portfolio that has been either recently approved for marketing or those that are in the pipeline of several biotech and pharmaceutical companies. This is largely based on their ability to be highly specific relative to small molecules. However, by virtue of being a large protein, and having a complex structure with structural variability arising from production using recombinant gene technology in cell lines, such therapeutics run the risk of being recognized as foreign by a host immune system. In the context of immune-mediated adverse effects that have been documented to biological drugs thus far, including infusion reactions, and the evolving therapeutic platforms in the pipeline that engineer different functional modules in a biotherapeutic, it is critical to understand the interplay of the adaptive and innate immune responses, the pathophysiology of immunogenicity to biological drugs in instances where there have been immune-mediated adverse clinical sequelae and address technical approaches for their laboratory evaluation. The current paradigm in immunogenicity evaluation has a tiered approach to the detection and characterization of anti-drug antibodies (ADAs) elicited in vivo to a biotherapeutic; alongside with the structural, biophysical, and molecular information of the therapeutic, these analytical assessments form the core of the immunogenicity risk assessment. However, many of the immune-mediated adverse effects attributed to ADAs require the formation of a drug/ADA immune complex (IC) intermediate that can have a variety of downstream effects. This review will focus on the activation of potential immunopathological pathways arising as a consequence of circulating as well as cell surface bound drug bearing ICs, risk factors that are intrinsic either to the therapeutic molecule or to the host that might predispose to IC-mediated effects, and review the recent literature on prevalence and intensity of established examples of type II and III hypersensitivity reactions that follow the administration of a biotherapeutic. Additionally, we propose methods for the study of immune parameters specific to the biology of ICs that could be of use in conjunction with the detection of ADAs in circulation.

10.
Arthritis Rheumatol ; 68(3): 627-38, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26473409

RESUMO

OBJECTIVE: To determine at the phenotypic, functional, and transcriptional levels whether abatacept, a CTLA-4Ig molecule that binds with high affinity to CD80/86 on antigen-presenting cells (APCs) and is used to treat rheumatoid arthritis, induces a state of immunologic tolerance in T cells and dendritic cells in mice. METHODS: We investigated the capacity of abatacept to regulate the development of antigen-specific immunologic tolerance in vivo using murine models of priming and tolerance to generate highly purified antigen-specific T cell populations and CD11c+ APCs. These were combined with detailed immunologic and full genome transcriptional analyses. RESULTS: We found that abatacept inhibited T cell activation, but did not render T cells anergic or lead to the generation of Treg cells. However, it induced a sustained inhibition of T cell activation due to the inability of these cells to progress through the cell cycle following T cell receptor stimulation. We also observed that this state was accompanied by an inhibition of dendritic cell activation due to their reduced licensing by T cells. CONCLUSION: This study provides detailed insight into the mode of action of abatacept, demonstrating that its effectiveness is not due to the induction of T cell tolerance, but rather to a sustained inhibition of T cell activation that results in reduced functionality of APCs, with significant implications for its clinical application.


Assuntos
Abatacepte/farmacologia , Células Apresentadoras de Antígenos/efeitos dos fármacos , Antirreumáticos/farmacologia , Tolerância Imunológica/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Transferência Adotiva , Animais , Antígenos/imunologia , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Imunológicos , RNA/isolamento & purificação , Linfócitos T/imunologia , Análise Serial de Tecidos , Regulação para Cima/efeitos dos fármacos
11.
J Pharmacol Exp Ther ; 355(3): 506-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26442523

RESUMO

BMS-931699 (lulizumab pegol), a domain antibody (dAb) conjugated with 40-kDa branched polyethylene glycol, is a human anti-CD28 receptor antagonist under development for the treatment of inflammatory and autoimmune diseases. In the present work, the minimal anticipated biologic effect level (MABEL) was determined for BMS-931699 by integrating all the available preclinical data. The relevance of the in vitro mixed lymphocyte reaction (MLR) assay to a whole blood CD28 receptor occupancy (RO) assessment, as well as the relationship between the CD28 RO and the inhibition of T-cell-dependent antibody response to keyhole limpet hemocyanin in vivo, was demonstrated through an integrated pharmacokinetic/pharmacodynamic analysis using anti-hCD28 dAb-001 (differing from BMS-931699 by two additional amino acids at the N-terminus) and a mouse surrogate. Based on this analysis, the EC10 value (0.32 nM) from the human MLR assay and the human plasma volume (0.04 l/kg) were employed to calculate the MABEL (0.01 mg) of BMS-931699 in humans, with a CD28 RO predicted to be ≤10%. The estimated MABEL dose was threefold higher than the value derived from the binding constant and twofold less than the MABEL converted from animal efficacy studies based on the body surface area. Furthermore, it was 2900-fold lower than the human equivalent dose derived from the no observed adverse effect level in monkeys (15 mg/kg/week for 5 doses, intravenous dosing) with a 10-fold safety factor applied. Therefore, the MABEL dose represented a sound approach to mitigate any potential risk in targeting CD28 and was successfully used as the first-in-human starting dose for BMS-931699.


Assuntos
Anticorpos/farmacologia , Antígenos CD28/antagonistas & inibidores , Polietilenoglicóis/farmacologia , Polietilenoglicóis/farmacocinética , Algoritmos , Animais , Superfície Corporal , Relação Dose-Resposta a Droga , Feminino , Hemocianinas/antagonistas & inibidores , Humanos , Teste de Cultura Mista de Linfócitos , Macaca fascicularis , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Testes de Sensibilidade Microbiana , Monócitos/efeitos dos fármacos
12.
J Med Chem ; 58(10): 4278-90, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25905990

RESUMO

An empirical approach to improve the microsomal stability and CYP inhibition profile of lead compounds 1a and 1b led to the identification of 5 (BMS-341) as a dissociated glucocorticoid receptor modulator. Compound 5 showed significant improvements in pharmacokinetic properties and, unlike compounds 1a-b, displayed a linear, dose-dependent pharmacokinetic profile in rats. When tested in a chronic model of adjuvant-induced arthritis in rat, the ED50 of 5 (0.9 mg/kg) was superior to that of both 1a and 1b (8 and 17 mg/kg, respectively).


Assuntos
Artrite Experimental/tratamento farmacológico , Inibidores das Enzimas do Citocromo P-450/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Receptores de Glucocorticoides/metabolismo , Tiadiazóis/farmacologia , Animais , Sangue/efeitos dos fármacos , Sangue/metabolismo , Técnicas de Química Sintética , Citocromo P-450 CYP3A , Inibidores do Citocromo P-450 CYP3A/química , Inibidores do Citocromo P-450 CYP3A/farmacologia , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Estabilidade de Medicamentos , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/farmacocinética , Humanos , Masculino , Ratos Endogâmicos Lew , Receptores de Glucocorticoides/agonistas , Relação Estrutura-Atividade , Tiadiazóis/química , Tiadiazóis/farmacocinética , Fator de Transcrição AP-1/metabolismo
13.
Bioorg Med Chem Lett ; 24(24): 5721-5726, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25453808

RESUMO

A new class of Janus kinase (JAK) inhibitors was discovered using a rationally designed pyrrolo[1,2-b]pyridazine-3-carboxamide scaffold. Preliminary studies identified (R)-(2,2-dimethylcyclopentyl)amine as a preferred C4 substituent on the pyrrolopyridazine core (3b). Incorporation of amino group to 3-position of the cyclopentane ring resulted in a series of JAK3 inhibitors (4g-4j) that potently inhibited IFNγ production in an IL2-induced whole blood assay and displayed high functional selectivity for JAK3-JAK1 pathway relative to JAK2. Further modifications led to the discovery of an orally bioavailable (2-fluoro-2-methylcyclopentyl)amino analogue 5g which is a nanomolar inhibitor of both JAK3 and TYK2, functionally selective for the JAK3-JAK1 pathway versus JAK2, and active in a human whole blood assay.


Assuntos
Descoberta de Drogas , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Piridazinas/química , Pirróis/química , Administração Oral , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Conformação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Relação Estrutura-Atividade , Distribuição Tecidual
14.
Bioorg Med Chem Lett ; 24(15): 3268-73, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24980053

RESUMO

Acylureas and acyclic imides are found to be excellent isosteres for 2-acylamino-1,3,4-thiadiazole in the azaxanthene-based series of glucocorticoid receptor (GR) agonists. The results reported herein show that primary acylureas maintain high affinity and selectivity for GR while providing improved CYP450 inhibition and pharmacokinetic profile over 2-acylamino-1,3,4-thiadiazoles. General methods for synthesis of a variety of acylureas and acyclic imides from a carboxylic acid were utilized and are described.


Assuntos
Descoberta de Drogas , Compostos Heterocíclicos com 3 Anéis/farmacologia , Receptores de Glucocorticoides/agonistas , Tiadiazóis/farmacologia , Ureia/farmacologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Compostos Heterocíclicos com 3 Anéis/síntese química , Compostos Heterocíclicos com 3 Anéis/química , Humanos , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade , Tiadiazóis/química , Ureia/análogos & derivados , Ureia/química
15.
J Exp Med ; 211(2): 297-311, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24493803

RESUMO

Mounting evidence in models of both autoimmunity and chronic viral infection suggests that the outcome of T cell activation is critically impacted by the constellation of co-stimulatory and co-inhibitory receptors expressed on the cell surface. Here, we identified a critical role for the co-inhibitory SLAM family member 2B4 (CD244) in attenuating primary antigen-specific CD8(+) T cell responses in the presence of immune modulation with selective CD28 blockade. Our results reveal a specific up-regulation of 2B4 on antigen-specific CD8(+) T cells in animals in which CD28 signaling was blocked. However, 2B4 up-regulation was not observed in animals treated with CTLA-4 Ig (abatacept) or CD28 blockade in the presence of anti-CTLA-4 mAb. 2B4 up-regulation after CD28 blockade was functionally significant, as the inhibitory impact of CD28 blockade was diminished when antigen-specific CD8(+) T cells were deficient in 2B4. In contrast, 2B4 deficiency had no effect on CD8(+) T cell responses during unmodified rejection or in the presence of CTLA-4 Ig. We conclude that blockade of CD28 signals in the presence of preserved CTLA-4 signals results in the unique up-regulation of 2B4 on primary CD8(+) effectors, and that this 2B4 expression plays a critical functional role in controlling antigen-specific CD8(+) T cell responses.


Assuntos
Antígenos CD/biossíntese , Antígenos CD28/antagonistas & inibidores , Linfócitos T CD8-Positivos/imunologia , Receptores Imunológicos/biossíntese , Abatacepte , Aloenxertos , Animais , Anticorpos Monoclonais/administração & dosagem , Antígenos CD/genética , Antígeno B7-H1/metabolismo , Linfócitos T CD4-Positivos/imunologia , Antígeno CTLA-4/antagonistas & inibidores , Sobrevivência de Enxerto/imunologia , Imunoconjugados/administração & dosagem , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Modelos Imunológicos , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Transdução de Sinais/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária , Transplante de Pele , Regulação para Cima
16.
J Immunol ; 191(9): 4599-610, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24081989

RESUMO

Targeting the CD28-CD80/86 pathway with an anti-CD28 antagonist is a promising alternative to current therapies for autoimmunity. However, attempts at generating conventional anti-CD28 mAbs lacking stimulatory activity has been challenging. In this study, we describe anti-human CD28 receptor antagonist domain Abs (dAbs) that are specific for human CD28. These dAbs are potent inhibitors of T cell activation, with an EC50 of 35 ± 14 ng/ml for inhibition of proliferation. The EC50 of 53 ± 11 ng/ml in an ex vivo CD28 receptor occupancy assay corresponds with in vitro functional activity, suggesting a direct correlation. The anti-CD28 dAb is equipotent in the inhibition of CD80- and CD86-mediated T cell proliferation and does not interfere with CTLA-4-mediated downmodulation of CD86 expression on APCs. The anti-CD28 dAbs are monomeric and do not demonstrate any evidence of agonism or costimulatory activity. In cynomolgus monkeys, the anti-CD28 dAb demonstrated pharmacodynamic activity, as measured by the inhibition of a T cell-dependent Ab response, without evidence of T cell depletion or cytokine release. Furthermore, there was a strong correlation between systemic exposure, duration, and extent of CD28 receptor occupancy, and pharmacodynamic activity. Taken together, these data support clinical evaluation of this novel anti-CD28 dAb for the treatment of autoimmune diseases.


Assuntos
Antígeno B7-1/imunologia , Antígeno B7-2/imunologia , Antígenos CD28/antagonistas & inibidores , Antígenos CD28/imunologia , Linfócitos T/imunologia , Animais , Anticorpos/imunologia , Células Apresentadoras de Antígenos/imunologia , Doenças Autoimunes/terapia , Antígeno CTLA-4/imunologia , Proliferação de Células , Humanos , Ativação Linfocitária/imunologia , Macaca fascicularis
17.
Bioorg Med Chem Lett ; 23(20): 5571-4, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24011644

RESUMO

A series of heterocyclic glucocorticoid receptor (GR) modulators with 2,2-dimethyl-3-phenyl-N-(thiazol or thiadiazol-2-yl)propanamide core are described. Structure-activity relationships suggest a combination of H-bond acceptor and a 4-fluorophenyl moiety as being important structural components contributing to the glucocorticoid receptor binding and functional activity for this series of GR modulators.


Assuntos
Amidas/química , Compostos Heterocíclicos/química , Receptores de Glucocorticoides/agonistas , Tiadiazóis/química , Tiazóis/química , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/metabolismo , Ligação Proteica , Receptores de Glucocorticoides/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
18.
Bioorg Med Chem Lett ; 23(19): 5448-51, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23916594

RESUMO

SAR was used to further develop an indazole class of non-steroidal glucocorticoid receptor agonists aided by a GR LBD (ligand-binding domain)-agonist co-crystal structure described in the accompanying paper. Progress towards discovering a dissociated GR agonist guided by human in vitro assays biased the optimization of this compound series towards partial agonists that possessed excellent selectivity against other nuclear hormone receptors.


Assuntos
Indazóis/síntese química , Indazóis/farmacologia , Receptores de Glucocorticoides/agonistas , Amidas/química , Amidas/farmacologia , Humanos , Indazóis/química , Modelos Moleculares , Ligação Proteica/efeitos dos fármacos , Receptores de Glucocorticoides/química , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia , Ureia/química , Ureia/farmacologia
19.
Bioorg Med Chem Lett ; 23(19): 5442-7, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23953070

RESUMO

Modification of a phenolic lead structure based on lessons learned from increasing the potency of steroidal glucocorticoid agonists lead to the discovery of exceptionally potent, nonsteroidal, indazole GR agonists. SAR was developed to achieve good selectivity against other nuclear hormone receptors with the ultimate goal of achieving a dissociated GR agonist as measured by human in vitro assays. The specific interactions by which this class of compounds inhibits GR was elucidated by solving an X-ray co-crystal structure.


Assuntos
Amidas/química , Amidas/farmacologia , Descoberta de Drogas , Receptores de Glucocorticoides/agonistas , Sítios de Ligação , Cristalografia por Raios X , Humanos , Indazóis/química , Indazóis/farmacologia , Estrutura Molecular , Ligação Proteica/efeitos dos fármacos , Esteroides/química , Esteroides/farmacologia , Relação Estrutura-Atividade
20.
Autoimmun Rev ; 12(7): 758-67, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23340277

RESUMO

Rheumatoid arthritis (RA) is a multifactorial and polygenic immune-mediated disease, the pathogenesis of which involves different cell types. T and B lymphocytes, macrophages, endothelial cells, fibroblasts and osteoclasts have all been implicated in mediating the production of autoantibodies, proinflammatory cytokines and ultimately bone erosions. Cytotoxic T lymphocyte-associated antigen 4 immunoglobulin fusion protein (CTLA-4-Ig, abatacept) is a unique biologic agent targeting the co-stimulatory molecules CD80/CD86, and is indicated for the treatment of moderate-to-severe RA in patients who have had an inadequate response to one or more disease-modifying anti-rheumatic drugs, including methotrexate or anti-tumor necrosis factor agents. There is a growing body of evidence that, through selective modulation of the CD80/CD86 co-stimulatory molecules expressed by a variety of activated cell types, CTLA-4-Ig may inhibit the pathogenic RA process at several levels, both directly and indirectly. Here, we provide an overview of recent mechanistic studies of the action of CTLA-4-Ig on different cell types involved in mediating inflammation and joint damage in RA.


Assuntos
Antígeno CTLA-4/uso terapêutico , Imunoglobulinas/uso terapêutico , Animais , Antirreumáticos/imunologia , Antirreumáticos/farmacologia , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Antígeno CTLA-4/imunologia , Humanos , Imunoglobulinas/imunologia , Inflamação/imunologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA