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1.
Aliment Pharmacol Ther ; 58(9): 874-887, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37718932

RESUMO

BACKGROUND: Filgotinib 200 mg (FIL200) is an approved treatment for adults with moderately to severely active ulcerative colitis (UC). AIM: To report integrated safety data from the phase 2b/3 SELECTION study (NCT02914522) and its ongoing long-term extension study SELECTIONLTE (NCT02914535). METHODS: Safety outcomes were analysed in adults with moderately to severely active UC who received FIL200, filgotinib 100 mg (FIL100) or placebo once daily throughout the 11-week SELECTION induction study, the 47-week SELECTION maintenance study (if applicable) and SELECTIONLTE (if applicable). Exposure-adjusted incidence rates (EAIRs) per 100 censored patient-years of exposure with 95% confidence intervals were reported for treatment-emergent adverse events (AEs). Certain AE data were presented in subgroups, including age and prior biologic exposure status. RESULTS: This interim analysis included 1348 patients representing 3326.2 patient-years of exposure. Baseline characteristics of patients entering SELECTION were similar across treatment groups. EAIRs for serious infection, thromboembolic events and major adverse cardiovascular events (MACE) were consistently low across treatment groups. Most patients with MACE had cardiovascular risk factors. The EAIR for herpes zoster was numerically higher for FIL200 than for placebo. Infection incidences were numerically higher in biologic-experienced than biologic-naive patients. Higher incidences of certain AEs in patients 65 years of age or older were as expected. Four deaths occurred, including three cardiovascular deaths, none of which was considered related to filgotinib. CONCLUSION: FIL200 and FIL100 were well tolerated with no unexpected safety signals in patients with moderately to severely active UC, regardless of previous biologic exposure or age. GOV IDENTIFIERS (NCT NUMBERS): NCT02914522, NCT02914535.


Assuntos
Produtos Biológicos , Colite Ulcerativa , Adulto , Humanos , Produtos Biológicos/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Piridinas/uso terapêutico , Triazóis/uso terapêutico
2.
J Crohns Colitis ; 17(8): 1207-1216, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36928705

RESUMO

BACKGROUND AND AIMS: The efficacy of new therapies for ulcerative colitis [UC] is usually influenced by previous biologic use. These post hoc analyses of SELECTION, a placebo-controlled phase 2b/3 trial in patients with moderately to severely active UC, evaluated the efficacy of filgotinib, an oral Janus 1 kinase preferential inhibitor, with respect to prior biologic failure. METHODS: The effect of filgotinib 200 mg (FIL200) relative to placebo was compared in biologic-naïve and biologic-failed patient groups, and in further subgroups by number of failed biologics [1 or >1], biologic mechanism of action [MoA] classes [1 or 2] and tumour necrosis factor [TNF] antagonists [1 or >1]. Odds ratios [ORs] for clinical remission at week 10 [induction] and hazard ratios [HRs] for protocol-specific disease worsening [PSDW] from week 11 to week 58 [maintenance] were calculated. RESULTS: At week 10, FIL200-treated patients were more likely to achieve clinical remission than placebo-treated patients in the biologic-naïve (OR [95% confidence interval, CI]: 1.98 [1.14-3.44]) and biologic-failed (3.91 [1.33-11.48]) groups. During maintenance, FIL200-treated patients had a reduced risk of PSDW in the biologic-naïve (HR [95% CI]: 0.22 [0.11-0.44]) and biologic-failed (0.22 [0.12-0.40]) groups, and in all biologic-failed subgroups (except >1 TNF antagonist failure). The data suggest that the likelihood of PSDW at week 58 increased with increasing numbers of failed biologics. CONCLUSIONS: FIL200 induced and maintained benefits relative to placebo regardless of previous biologic use; however, the estimated therapeutic benefit was greatest in biologic-naïve patients and patients previously treated with one biologic or biologic MoA class. [ClinicalTrials.gov: NCT02914522].


Assuntos
Produtos Biológicos , Colite Ulcerativa , Inibidores de Janus Quinases , Humanos , Colite Ulcerativa/tratamento farmacológico , Piridinas/uso terapêutico , Triazóis/uso terapêutico , Inibidores de Janus Quinases/uso terapêutico , Produtos Biológicos/uso terapêutico
3.
Sci Rep ; 12(1): 15440, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104373

RESUMO

Nicotinamide N-methyltransferase (NNMT) is a metabolic regulator that catalyzes the methylation of nicotinamide (Nam) using the co-factor S-adenosyl-L-methionine to form 1-methyl-nicotinamide (MNA). Overexpression of NNMT and the presence of the active metabolite MNA is associated with a number of diseases including metabolic disorders. We conducted a high-throughput screening campaign that led to the identification of a tricyclic core as a potential NNMT small molecule inhibitor series. Elaborate medicinal chemistry efforts were undertaken and hundreds of analogs were synthesized to understand the structure activity relationship and structure property relationship of this tricyclic series. A lead molecule, JBSNF-000028, was identified that inhibits human and mouse NNMT activity, reduces MNA levels in mouse plasma, liver and adipose tissue, and drives insulin sensitization, glucose modulation and body weight reduction in a diet-induced obese mouse model of diabetes. The co-crystal structure showed that JBSNF-000028 binds below a hairpin structural motif at the nicotinamide pocket and stacks between Tyr-204 (from Hairpin) and Leu-164 (from central domain). JBSNF-000028 was inactive against a broad panel of targets related to metabolism and safety. Interestingly, the improvement in glucose tolerance upon treatment with JBSNF-000028 was also observed in NNMT knockout mice with diet-induced obesity, pointing towards the glucose-normalizing effect that may go beyond NNMT inhibition. JBSNF-000028 can be a potential therapeutic option for metabolic disorders and developmental studies are warranted.


Assuntos
Doenças Metabólicas , Nicotinamida N-Metiltransferase , Animais , Humanos , Camundongos , Glucose , Doenças Metabólicas/tratamento farmacológico , Niacinamida/metabolismo , Niacinamida/farmacologia , Nicotinamida N-Metiltransferase/metabolismo , Obesidade/tratamento farmacológico
4.
Sci Rep ; 8(1): 9408, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925868

RESUMO

Mitochondrial dysfunction is increasingly recognized as a contributor to age-related muscle loss and functional impairment. Therefore, we developed a high throughput screening strategy that enabled the identification of compounds boosting mitochondrial energy production in a human skeletal muscle cell model. Screening of 7949 pure natural products revealed 22 molecules that significantly increased oxygen consumption and ATP levels in myotubes. One of the most potent compounds was the flavanone hesperetin. Hesperetin (10 µM) increased intracellular ATP by 33% and mitochondrial spare capacity by 25%. Furthermore, the compound reduced oxidative stress in primary myotubes as well as muscle tissue in vivo. In aged mice administration of hesperetin (50 mg/kg/d) completely reverted the age-related decrease of muscle fiber size and improved running performance of treated animals. These results provide a novel screening platform for the discovery of drugs that can improve skeletal muscle function in patients suffering from sarcopenia or other disorders associated with mitochondrial dysfunction.


Assuntos
Mitocôndrias/metabolismo , Fibras Musculares Esqueléticas/citologia , Trifosfato de Adenosina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Hesperidina/farmacologia , Humanos , Potencial da Membrana Mitocondrial , Camundongos , Mitocôndrias/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Estresse Oxidativo/efeitos dos fármacos
5.
Sci Rep ; 8(1): 3660, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29483571

RESUMO

Nicotinamide N-methyltransferase (NNMT) is a cytosolic enzyme that catalyzes the transfer of a methyl group from the co-factor S-adenosyl-L-methionine (SAM) onto the substrate, nicotinamide (NA) to form 1-methyl-nicotinamide (MNA). Higher NNMT expression and MNA concentrations have been associated with obesity and type-2 diabetes. Here we report a small molecule analog of NA, JBSNF-000088, that inhibits NNMT activity, reduces MNA levels and drives insulin sensitization, glucose modulation and body weight reduction in animal models of metabolic disease. In mice with high fat diet (HFD)-induced obesity, JBSNF-000088 treatment caused a reduction in body weight, improved insulin sensitivity and normalized glucose tolerance to the level of lean control mice. These effects were not seen in NNMT knockout mice on HFD, confirming specificity of JBSNF-000088. The compound also improved glucose handling in ob/ob and db/db mice albeit to a lesser extent and in the absence of weight loss. Co-crystal structure analysis revealed the presence of the N-methylated product of JBSNF-000088 bound to the NNMT protein. The N-methylated product was also detected in the plasma of mice treated with JBSNF-000088. Hence, JBSNF-000088 may act as a slow-turnover substrate analog, driving the observed metabolic benefits.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/enzimologia , Nicotinamida N-Metiltransferase/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nicotinamida N-Metiltransferase/antagonistas & inibidores
6.
Bioorg Med Chem Lett ; 28(5): 922-925, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29433927

RESUMO

Nicotinamide N-methyltransferase (NNMT) has been linked to obesity and diabetes. We have identified a novel nicotinamide (NA) analog, compound 12 that inhibited NNMT enzymatic activity and reduced the formation of 1-methyl-nicotinamide (MNA), the primary metabolite of NA by ∼80% at 2 h when dosed in mice orally at 50 mg/kg.


Assuntos
Inibidores Enzimáticos/farmacologia , Niacinamida/farmacologia , Nicotinamida N-Metiltransferase/antagonistas & inibidores , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Niacinamida/síntese química , Niacinamida/química , Nicotinamida N-Metiltransferase/metabolismo , Relação Estrutura-Atividade
7.
Biochem Biophys Res Commun ; 491(2): 416-422, 2017 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-28720493

RESUMO

Nicotinamide N-methyltransferase (NNMT) is a S-adenosyl-l-methionine (SAM)-dependent enzyme that catalyzes N-methylation of nicotinamide (NA) and other pyridines to form N-methyl pyridinium ions. Here we report the first ternary complex X-ray crystal structures of monkey NNMT and mouse NNMT in bound form with the primary endogenous product, 1-methyl nicotinamide (MNA) and demethylated cofactor, S-adenosyl-homocysteine (SAH) determined at 2.30 Å and 1.88 Å respectively. The structural fold of these enzymes is identical to human NNMT. It is known that the primary endogenous product catalyzed by NNMT, MNA is a specific inhibitor of NNMT. Our data clearly indicates that the MNA binds to the active site and it would be trapped in the active site due to the formation of the bridge between the pole (long helix, α3) and long C-terminal loop. This might explain the mechanism of MNA acting as a feedback inhibitor of NNMT.


Assuntos
Retroalimentação Fisiológica , Niacinamida/análogos & derivados , Nicotinamida N-Metiltransferase/química , S-Adenosilmetionina/química , Sequência de Aminoácidos , Animais , Domínio Catalítico , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Macaca mulatta , Camundongos , Modelos Moleculares , Niacinamida/química , Niacinamida/metabolismo , Nicotinamida N-Metiltransferase/antagonistas & inibidores , Nicotinamida N-Metiltransferase/genética , Nicotinamida N-Metiltransferase/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , S-Adenosilmetionina/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
8.
Onco Targets Ther ; 10: 1295-1305, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28280364

RESUMO

BACKGROUND: Symptomatic anemia is a frequent and severe complication of chemotherapy that is commonly treated with erythropoiesis-stimulating agents. The primary objective of this study was to assess the change in hemoglobin levels in patients with chemotherapy-induced anemia (CIA) following treatment with biosimilar Retacrit® (epoetin zeta). Secondary objectives included changes in hematologic parameters and tolerability. METHODS: This was a non-interventional, multicenter, long-term observational study that is part of an ongoing surveillance program for epoetin zeta. Adult patients (N=291) with solid tumors, malignant lymphomas or multiple myeloma, and chemotherapy-induced symptomatic anemia, who were eligible for treatment with biosimilar epoetin zeta, were enrolled. Patients were evaluated at enrollment, 3 months, and 6 months. RESULTS: Evaluable patients had lymphoma or myeloma (n=30) or solid tumors (n=260). At 3 months, patients with lymphoma and myeloma showed the greatest increase in mean (SD) hemoglobin from 9.2 (0.9) to 11.0 (1.8) g/dL, whereas patients with breast cancer showed the smallest increase from 10.0 (1.0) to 11.1 (1.2) g/dL. At 6 months, the greatest mean increase occurred in patients with lymphoma or myeloma from 11.0 (1.8) to 11.7 (2.3) g/dL, and the smallest in patients with other solid tumors from 10.9 (1.4) to 11.1 (1.5) g/dL. Patient evaluation of epoetin zeta therapy was positive, as most patients expressed satisfaction with epoetin zeta treatment during the study, compliance with treatment was high, and most indicated their willingness to be retreated if necessary. Epoetin zeta was also well tolerated; overall, in 25 patients (8.6%), there were 31 adverse events. CONCLUSION: Despite variability among different disease groups, epoetin zeta was effective and well tolerated in patients with different types of solid tumors and hematologic malignancies.

9.
Adv Ther ; 33(11): 1983-2000, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27743353

RESUMO

INTRODUCTION: Febrile neutropenia (FN) is a serious and frequent complication of cytotoxic chemotherapy. Biosimilar filgrastim (Nivestim™, Hospira Inc, A Pfizer Company, Lake Forest, IL, USA) is a granulocyte-colony stimulating factor licensed for the treatment of neutropenia and FN induced by myelosuppressive chemotherapy. The primary goal of this VENICE study (ClinicalTrials.gov identifier, NCT01627990) was to observe the tolerability, safety and efficacy of biosimilar filgrastim in patients receiving cancer chemotherapy. METHODS: This was a prospective, multicenter, non-interventional, longitudinal study. Consenting adult patients with solid tumors or hematologic malignancies for whom cytotoxic chemotherapy and treatment with biosimilar filgrastim was planned were enrolled. RESULTS: Among the enrolled patients (N = 386), 81% were female, with a median age (range) of 61 (22-92) years, with 39% >65 years old. Most patients (n = 338; 88%) had solid tumors and the remainder (n = 49; 13%) had hematological malignancies. The majority of the patients (64%) received biosimilar filgrastim as primary prophylaxis and 36% as secondary prophylaxis. At the follow-up visits, for the majority of patients (95.6%) there had been no change in chemotherapy dose due to FN. For two patients (0.5%) the chemotherapy was discontinued due to FN and for four patients (1.0%) the chemotherapy dose was reduced due to FN. For the majority of patients (96.9%) the chemotherapy cycle following the first biosimilar filgrastim treatment was not delayed due to FN. For 3 patients (0.8%), the chemotherapy was delayed following the first biosimilar filgrastim treatment. Less than one-third (29.8%) of the patients experienced ≥1 adverse event that was at least potentially related to biosimilar filgrastim treatment. CONCLUSIONS: Biosimilar filgrastim was effective and well-tolerated in both the primary and secondary prophylactic setting in patients undergoing chemotherapy for solid tumors and hematological malignancies. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT01627990. FUNDING: Hospira Inc, A Pfizer Company, Lake Forest, IL, USA.


Assuntos
Antineoplásicos , Medicamentos Biossimilares , Neutropenia Febril , Filgrastim , Neoplasias/tratamento farmacológico , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Medicamentos Biossimilares/administração & dosagem , Medicamentos Biossimilares/efeitos adversos , Citotoxinas , Neutropenia Febril/induzido quimicamente , Neutropenia Febril/diagnóstico , Neutropenia Febril/prevenção & controle , Feminino , Filgrastim/administração & dosagem , Filgrastim/efeitos adversos , Fármacos Hematológicos/administração & dosagem , Fármacos Hematológicos/efeitos adversos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Profilaxia Pré-Exposição/métodos , Estudos Prospectivos , Prevenção Secundária/métodos , Resultado do Tratamento
10.
Eur J Immunol ; 45(7): 2008-16, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25884798

RESUMO

Under homeostasis, liver sinusoidal endothelial cells (LSECs) shift intrahepatic T-cell responses towards tolerance. However, the role of LSECs in the regulation of T-cell-induced liver inflammation is less clear. Here, we studied the capacity of LSECs to modulate pro-inflammatory Th1-cell differentiation in mice. Using in vitro co-culture systems and subsequent cytokine analysis, we showed that LSECs induced high amounts of the anti-inflammatory cytokine IL-10 in developing Th1 cells. These LSEC-stimulated Th1 cells had no pro-inflammatory capacity in vivo but instead actively suppressed an inflammatory Th1-cell-induced delayed-type hypersensitivity reaction. Blockage of IL-10 signaling in vivo inhibited immunosuppressive activity of LSEC-stimulated Th1 cells. We identified the Notch pathway as a mechanism how LSECs trigger IL-10 expression in Th1 cells. LSECs expressed high levels of the Delta-like and Jagged family of Notch ligands and induced expression of the Notch target genes hes-1 and deltex-1 in Th1 cells. Blockade of Notch signaling selectively inhibited IL-10 induction in Th1 cells by LSECs. Our findings suggest that LSEC-induced IL-10 expression in Th1 cells via the Notch pathway may contribute to the control of hepatic inflammatory immune responses by induction of a self-regulatory mechanism in pro-inflammatory Th1 cells.


Assuntos
Células Endoteliais/imunologia , Tolerância Imunológica/imunologia , Interleucina-10/imunologia , Receptores Notch/imunologia , Transdução de Sinais , Células Th1/imunologia , Animais , Diferenciação Celular/imunologia , Separação Celular , Técnicas de Cocultura , Citometria de Fluxo , Fígado/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/imunologia
11.
J Exp Med ; 211(9): 1807-19, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25073792

RESUMO

Secretion of the immunosuppressive cytokine interleukin (IL) 10 by effector T cells is an essential mechanism of self-limitation during infection. However, the transcriptional regulation of IL-10 expression in proinflammatory T helper (Th) 1 cells is insufficiently understood. We report a crucial role for the transcriptional regulator Blimp-1, induced by IL-12 in a STAT4-dependent manner, in controlling IL-10 expression in Th1 cells. Blimp-1 deficiency led to excessive inflammation during Toxoplasma gondii infection with increased mortality. IL-10 production from Th1 cells was strictly dependent on Blimp-1 but was further enhanced by the synergistic function of c-Maf, a transcriptional regulator of IL-10 induced by multiple factors, such as the Notch pathway. We found Blimp-1 expression, which was also broadly induced by IL-27 in effector T cells, to be antagonized by transforming growth factor (TGF) ß. While effectively blocking IL-10 production from Th1 cells, TGF-ß shifted IL-10 regulation from a Blimp-1-dependent to a Blimp-1-independent pathway in IL-27-induced Tr1 (T regulatory 1) cells. Our findings further illustrate how IL-10 regulation in Th cells relies on several transcriptional programs that integrate various signals from the environment to fine-tune expression of this critical immunosuppressive cytokine.


Assuntos
Interleucina-10/biossíntese , Células Th1/imunologia , Células Th1/metabolismo , Fatores de Transcrição/imunologia , Animais , Interleucina-10/genética , Interleucina-12/metabolismo , Interleucinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fator 1 de Ligação ao Domínio I Regulador Positivo , Proteínas Proto-Oncogênicas c-maf/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-maf/genética , Proteínas Proto-Oncogênicas c-maf/imunologia , Receptores Notch/metabolismo , Fator de Transcrição STAT4/deficiência , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Transdução de Sinais , Toxoplasmose/genética , Toxoplasmose/imunologia , Toxoplasmose/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/metabolismo
12.
Biochem Biophys Res Commun ; 449(3): 327-31, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-24845568

RESUMO

Phosphatidylinositol-5-phosphate 4-kinase, type II, beta (PIP5K2B) is linked to the pathogenesis of obesity, insulin resistance and diabetes. Here, we describe the identification of a novel pyrimidine-2,4-diamine PIP5K2B inhibitor, designated SAR088. The compound was identified by high-throughput screening and subsequently characterized in vitro and in vivo. SAR088 showed reasonable potency, selectivity and physicochemical properties in enzymatic and cellular assays. In vivo, SAR088 lowered blood glucose levels of obese and hyperglycemic male Zucker diabetic fatty rats treated for 3 weeks. Thus, SAR088 represents the first orally available and in vivo active PIP5K2B inhibitor and provides an excellent starting point for the development of potent and selective PIP5K2B inhibitors for the treatment of insulin resistance and diabetes.


Assuntos
Glicemia/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Imidazolidinas/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Pirimidinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Imidazolidinas/química , Resistência à Insulina , Masculino , Camundongos , Pirimidinas/química , Ratos Zucker , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
13.
Hepatology ; 55(6): 1976-84, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22109893

RESUMO

UNLABELLED: Gut-activated T cells migrating into the liver can cause extraintestinal manifestations of inflammatory bowel disease. T cells acquire a gut-homing phenotype dependent on retinoic acid (RA) provided by intestinal dendritic cells (DC). We investigated whether liver antigen-presenting cells can induce gut tropism supporting an enterohepatic lymphocyte circulation. Priming of CD4(+) T cells by liver sinusoidal endothelial cells (LSEC) supported migration into gut and gut-associated lymphoid tissue. As observed for T cells primed by intestinal DCs, this gut tropism depended on α(4) ß(7) integrin and CC chemokine receptor 9 (CCR9) expression by LSEC-primed CD4(+) T cells. The induction of gut-homing molecules was mediated by RA, a derivate of vitamin A that is stored in large amounts within the liver. LSECs expressed functional retinal dehydrogenases and could convert vitamin A to RA. Conversely, the lack of signaling via the RA receptor prevented the expression of α(4) ß(7) integrin and CCR9 on LSEC-primed CD4(+) T cells, consequently reducing their in vivo migration to the intestine. Other liver antigen-presenting cells failed to support high expression of α(4) ß(7) integrin on CD4(+) T cells, thus, the potential to induce gut homing is restricted to LSECs. CONCLUSION: The capacity to promote gut tropism via vitamin A use is not unique for intestinal DCs but is also a feature of LSECs. Our data support the assumption that CD4(+) T cells can migrate from the liver to the gut as one branch of a postulated enterohepatic lymphocyte circulation.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Células Endoteliais/fisiologia , Intestinos/imunologia , Fígado/imunologia , Tretinoína/fisiologia , Família Aldeído Desidrogenase 1 , Aldeído Oxirredutases/genética , Sequência de Aminoácidos , Animais , Movimento Celular , Circulação Êntero-Hepática , Integrinas/análise , Isoenzimas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Receptores CCR/análise , Retinal Desidrogenase/genética , Tropismo
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