Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Cell Metab ; 32(1): 128-143.e5, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32516576

RESUMO

Macrophages reprogram their lipid metabolism in response to activation signals. However, a systems-level understanding of how different pro-inflammatory stimuli reshape the macrophage lipidome is lacking. Here, we use complementary "shotgun" and isotope tracer mass spectrometry approaches to define the changes in lipid biosynthesis, import, and composition of macrophages induced by various Toll-like receptors (TLRs) and inflammatory cytokines. "Shotgun" lipidomics data revealed that different TLRs and cytokines induce macrophages to acquire distinct lipidomes, indicating their specificity in reshaping lipid composition. Mechanistic studies showed that differential reprogramming of lipid composition is mediated by the opposing effects of MyD88- and TRIF-interferon-signaling pathways. Finally, we applied these insights to show that perturbing reprogramming of lipid composition can enhance inflammation and promote host defense to bacterial challenge. These studies provide a framework for understanding how inflammatory stimuli reprogram lipid composition of macrophages while providing a knowledge platform to exploit differential lipidomics to influence immunity.


Assuntos
Lipidômica , Macrófagos/metabolismo , Receptores Toll-Like/metabolismo , Animais , Linhagem Celular , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais
2.
Cell Rep ; 25(10): 2919-2934.e8, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30517876

RESUMO

It is well understood that fatty acids can be synthesized, imported, and modified to meet requisite demands in cells. However, following the movement of fatty acids through the multiplicity of these metabolic steps has remained difficult. To better address this problem, we developed Fatty Acid Source Analysis (FASA), a model that defines the contribution of synthesis, import, and elongation pathways to fatty acid homeostasis in saturated, monounsaturated, and polyunsaturated fatty acid pools. Application of FASA demonstrated that elongation can be a major contributor to cellular fatty acid content and showed that distinct pro-inflammatory stimuli (e.g., Toll-like receptors 2, 3, or 4) specifically reprogram homeostasis of fatty acids by differential utilization of synthetic and elongation pathways in macrophages. In sum, this modeling approach significantly advances our ability to interrogate cellular fatty acid metabolism and provides insight into how cells dynamically reshape their lipidomes in response to metabolic or inflammatory signals.


Assuntos
Ácidos Graxos/metabolismo , Marcação por Isótopo/métodos , Modelos Biológicos , Animais , Carbono/metabolismo , Linhagem Celular , Ácidos Graxos Insaturados/metabolismo , Homeostase , Humanos , Inflamação/patologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL
3.
Proc Natl Acad Sci U S A ; 115(46): E10898-E10906, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30373813

RESUMO

Chimeric antigen receptor (CAR) T cells with a long-lived memory phenotype are correlated with durable, complete remissions in patients with leukemia. However, not all CAR T cell products form robust memory populations, and those that do can induce chronic B cell aplasia in patients. To address these challenges, we previously developed a switchable CAR (sCAR) T cell system that allows fully tunable, on/off control over engineered cellular activity. To further evaluate the platform, we generated and assessed different murine sCAR constructs to determine the factors that afford efficacy, persistence, and expansion of sCAR T cells in a competent immune system. We find that sCAR T cells undergo significant in vivo expansion, which is correlated with potent antitumor efficacy. Most importantly, we show that the switch dosing regimen not only allows control over B cell populations through iterative depletion and repopulation, but that the "rest" period between dosing cycles is the key for induction of memory and expansion of sCAR T cells. These findings introduce rest as a paradigm in enhancing memory and improving the efficacy and persistence of engineered T cell products.


Assuntos
Bioengenharia/métodos , Imunoterapia Adotiva/métodos , Animais , Antígenos CD19/imunologia , Linfócitos B/imunologia , Citocinas/metabolismo , Citotoxicidade Imunológica/imunologia , Feminino , Região de Troca de Imunoglobulinas/genética , Região de Troca de Imunoglobulinas/imunologia , Ativação Linfocitária/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Modelos Biológicos , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia
4.
J Mammary Gland Biol Neoplasia ; 22(1): 59-69, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28124184

RESUMO

Reelin is a regulator of cell migration in the nervous system, and has other functions in the development of a number of non-neuronal tissues. In addition, alterations in reelin expression levels have been reported in breast, pancreatic, liver, gastric, and other cancers. Reelin is normally expressed in mammary gland stromal cells, but whether stromal reelin contributes to breast cancer progression is unknown. Herein, we used a syngeneic mouse mammary tumor transplantation model to examine the impact of host-derived reelin on breast cancer progression. We found that transplanted syngeneic tumors grew more slowly in reelin-deficient (rl Orl -/- ) mice and had delayed metastatic colonization of the lungs. Immunohistochemistry of primary tumors revealed that tumors grown in rl Orl -/- animals had fewer blood vessels and increased macrophage infiltration. Gene expression studies from tumor tissues indicate that loss of host-derived reelin alters the balance of M1- and M2-associated macrophage markers, suggesting that reelin may influence the polarization of these cells. Consistent with this, rl Orl -/- M1-polarized bone marrow-derived macrophages have heightened levels of the M1-associated cytokines iNOS and IL-6. Based on these observations, we propose a novel function for the reelin protein in breast cancer progression.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Moléculas de Adesão Celular Neuronais/metabolismo , Proliferação de Células/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Proteínas do Tecido Nervoso/metabolismo , Serina Endopeptidases/metabolismo , Animais , Mama/metabolismo , Mama/patologia , Linhagem Celular , Linhagem Celular Tumoral , Citocinas/metabolismo , Progressão da Doença , Feminino , Expressão Gênica/fisiologia , Células HEK293 , Humanos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Proteína Reelina
5.
Dev Dyn ; 246(4): 217-226, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27739126

RESUMO

The reelin signaling pathway has been established as an important regulator of cell migration during development of the central nervous system, and disruptions in reelin signaling alter the positioning of many types of neurons. Reelin is a large extracellular matrix glycoprotein and governs cell migration through activation of multiple intracellular signaling events by means of the receptors ApoE receptor 2 (ApoER2) and very low density lipoprotein receptor (VLDLR), and the intracellular adaptor protein Disabled-1 (Dab1). Earlier studies reported expression of reelin in nonneuronal tissues, but the functions of this signaling pathway outside of the nervous system have not been studied until recently. A large body of evidence now suggests that reelin functions during development and disease of multiple nonneuronal tissues. This review addresses recent advances in the field of nonneuronal reelin signaling. Developmental Dynamics 246:217-226, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Moléculas de Adesão Celular Neuronais/fisiologia , Proteínas da Matriz Extracelular/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Serina Endopeptidases/fisiologia , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Movimento Celular , Proteínas da Matriz Extracelular/metabolismo , Humanos , Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de LDL/metabolismo , Proteína Reelina , Serina Endopeptidases/metabolismo
6.
ASN Neuro ; 8(3)2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27364165

RESUMO

Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and major depressive disorders. Prior studies from our laboratory and others have demonstrated that the combinatorial effect of two factors-reduced expression of reelin protein and prenatal exposure to the organophosphate pesticide chlorpyrifos oxon-gives rise to acute biochemical effects and to morphological and behavioral phenotypes in adolescent and young adult mice. In the current study, we examine the consequences of these factors on reelin protein expression and neuronal cell morphology in adult mice. While the cell populations that express reelin in the adult brain appear unchanged in location and distribution, the levels of full length and cleaved reelin protein show persistent reductions following prenatal exposure to chlorpyrifos oxon. Cell positioning and organization in the hippocampus and cerebellum are largely normal in animals with either reduced reelin expression or prenatal exposure to chlorpyrifos oxon, but cellular complexity and dendritic spine organization is altered, with a skewed distribution of immature dendritic spines in adult animals. Paradoxically, combinatorial exposure to both factors appears to generate a rescue of the dendritic spine phenotypes, similar to the mitigation of behavioral and morphological changes observed in our prior study. Together, our observations support an interaction between reelin expression and chlorpyrifos oxon exposure that is not simply additive, suggesting a complex interplay between genetic and environmental factors in regulating brain morphology.


Assuntos
Encéfalo/patologia , Moléculas de Adesão Celular Neuronais/metabolismo , Clorpirifos/análogos & derivados , Proteínas da Matriz Extracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/patologia , Praguicidas/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Serina Endopeptidases/metabolismo , Fatores Etários , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Proteínas de Transporte/metabolismo , Moléculas de Adesão Celular Neuronais/genética , Proteínas de Ciclo Celular/metabolismo , Clorpirifos/toxicidade , Deficiências do Desenvolvimento/induzido quimicamente , Deficiências do Desenvolvimento/genética , Sistemas de Liberação de Medicamentos , Proteínas da Matriz Extracelular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/genética , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes Neurológicos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Neurônios/ultraestrutura , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/patologia , Proteína Reelina , Serina Endopeptidases/genética
7.
ASN Neuro ; 5(1): e00106, 2012 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23298182

RESUMO

Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders, including ASDs (autism spectrum disorders). In this study, we examined the combinatorial effect of two factors thought to be involved in autism--reduction in the expression of the extracellular matrix protein reelin and prenatal exposure to an organophosphate pesticide, CPO (chlorpyrifos oxon). Mice with reduced reelin expression or prenatal exposure to CPO exhibited subtle changes in ultrasound vocalization, open field behaviour, social interaction and repetitive behaviour. Paradoxically, mice exposed to both variables often exhibited a mitigation of abnormal behaviours, rather than increased behavioural abnormalities as expected. We identified specific differences in males and females in response to both of these variables. In addition to behavioural abnormalities, we identified anatomical alterations in the olfactory bulb, piriform cortex, hippocampus and cerebellum. As with our behavioural studies, anatomical alterations appeared to be ameliorated in the presence of both variables. While these observations support an interaction between loss of reelin expression and CPO exposure, our results suggest a complexity to this interaction beyond an additive effect of individual phenotypes.


Assuntos
Comportamento Animal/efeitos dos fármacos , Sintomas Comportamentais/induzido quimicamente , Encéfalo/efeitos dos fármacos , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Organofosfatos/toxicidade , Serina Endopeptidases/metabolismo , Acetilcolinesterase/metabolismo , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Moléculas de Adesão Celular Neuronais/genética , Colorimetria , Sistemas de Liberação de Medicamentos , Embrião de Mamíferos , Comportamento Exploratório/efeitos dos fármacos , Proteínas da Matriz Extracelular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Relações Interpessoais , Masculino , Camundongos , Camundongos Mutantes Neurológicos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/metabolismo , Proteína Reelina , Serina Endopeptidases/genética , Vocalização Animal/efeitos dos fármacos , beta-Galactosidase/metabolismo
8.
J Micromech Microeng ; 21(5): 54006, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21886945

RESUMO

Here we report on the development of torsional magnetic microactuators for displacing biological materials in implantable catheters. Static and dynamic behaviors of the devices were characterized in air and in fluid using optical experimental methods. The devices were capable of achieving large deflections (>60°) and had resonant frequencies that ranged from 70 Hz to 1.5 kHz in fluid. The effect of long-term actuation (>2.5 · 10(8) cycles) was quantified using resonant shift as the metric (Δf < 2%). Cell-clearing capabilities of the devices were evaluated by examining the effect of actuation on a layer of aggressively growing adherent cells. On average, actuated microdevices removed 37.4% of the adherent cell layer grown over the actuator surface. The effect of actuation time, deflection angle, and beam geometry were evaluated. The experimental results indicate that physical removal of adherent cells at the microscale is feasible using magnetic microactuation.

9.
Development ; 138(4): 767-76, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21266412

RESUMO

Reelin signaling is required for appropriate cell migration and ductal patterning during mammary gland morphogenesis. Dab1, an intracellular adaptor protein activated in response to reelin signaling, is expressed in the developing mammary bud and in luminal epithelial cells in the adult gland. Reelin protein is expressed in a complementary pattern, first in the epithelium overlying the mammary bud during embryogenesis and then in the myoepithelium and periductal stroma in the adult. Deletion in mouse of either reelin or Dab1 induced alterations in the development of the ductal network, including significant retardation in ductal elongation, decreased terminal branching, and thickening and disorganization of the luminal wall. At later stages, some mutant glands overcame these early delays, but went on to exhibit enlarged and chaotic ductal morphologies and decreased terminal branching: these phenotypes are suggestive of a role for reelin in spatial patterning or structural organization of the mammary epithelium. Isolated mammary epithelial cells exhibited decreased migration in response to exogenous reelin in vitro, a response that required Dab1. These observations highlight a role for reelin signaling in the directed migration of mammary epithelial cells driving ductal elongation into the mammary fat pad and provide the first evidence that reelin signaling may be crucial for regulating the migration and organization of non-neural tissues.


Assuntos
Glândulas Mamárias Animais/crescimento & desenvolvimento , Glândulas Mamárias Animais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transdução de Sinais , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Proliferação de Células , Células Cultivadas , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/embriologia , Camundongos , Camundongos Transgênicos , Mutação , Proteínas do Tecido Nervoso/genética , Proteína Reelina , Serina Endopeptidases/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-19162814

RESUMO

Here we demonstrate the functional capability of microfabricated magnetic actuators in clearing biological accumulation on a model catheter pore. Cell-clearing performance was quantitatively measured by comparing the effect of actuation on the cell density of aggressively growing adherent murine cells. Devices were actuated at a frequency of 100 Hz and a magnetic field of 17.8 kA/m for 30, 45, or 60 min. On average, microactuators removed 37.4% of the adherent cells. The results also revealed that the cell-clearing capability of the microactuator increased as a function of the actuation duration and angle of deflection.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos da radiação , Desinfecção/instrumentação , Contaminação de Equipamentos/prevenção & controle , Magnetismo/instrumentação , Sistemas Microeletromecânicos/instrumentação , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/prevenção & controle , Transdutores , Desinfecção/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização , Próteses e Implantes/efeitos adversos , Infecções Relacionadas à Prótese/etiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estresse Mecânico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...