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1.
Sci Transl Med ; 14(667): eabn7824, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36260690

RESUMO

Although combination therapy is the standard of care for relapsed/refractory non-Hodgkin's lymphoma (RR-NHL), combination treatment chosen for an individual patient is empirical, and response rates remain poor in individuals with chemotherapy-resistant disease. Here, we evaluate an experimental-analytic method, quadratic phenotypic optimization platform (QPOP), for prediction of patient-specific drug combination efficacy from a limited quantity of biopsied tumor samples. In this prospective study, we enrolled 71 patients with RR-NHL (39 B cell NHL and 32 NK/T cell NHL) with a median of two prior lines of treatment, at two academic hospitals in Singapore from November 2017 to August 2021. Fresh biopsies underwent ex vivo testing using a panel of 12 drugs with known efficacy against NHL to identify effective single and combination treatments. Individualized QPOP reports were generated for 67 of 75 patient samples, with a median turnaround time of 6 days from sample collection to report generation. Doublet drug combinations containing copanlisib or romidepsin were most effective against B cell NHL and NK/T cell NHL samples, respectively. Off-label QPOP-guided therapy offered at physician discretion in the absence of standard options (n = 17) resulted in five complete responses. Among patients with more than two prior lines of therapy, the rates of progressive disease were lower with QPOP-guided treatments than with conventional chemotherapy. Overall, this study shows that the identification of patient-specific drug combinations through ex vivo analysis was achievable for RR-NHL in a clinically applicable time frame. These data provide the basis for a prospective clinical trial evaluating ex vivo-guided combination therapy in RR-NHL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma não Hodgkin , Humanos , Estudos Prospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Combinação de Medicamentos
2.
J Exp Clin Cancer Res ; 41(1): 249, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35971164

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) remains difficult to treat due to limited effective treatment options. While the proteasome inhibitor bortezomib has shown promising preclinical activity in HCC, clinical trials of bortezomib showed no advantage over the standard-of-care treatment sorafenib, highlighting the need for more clinically relevant therapeutic strategies. Here, we propose that rational drug combination design and validation in patient-derived HCC avatar models such as patient-derived xenografts (PDXs) and organoids can improve proteasome inhibitor-based therapeutic efficacy and clinical potential. METHODS: HCC PDXs and the corresponding PDX-derived organoids (PDXOs) were generated from primary patient samples for drug screening and efficacy studies. To identify effective proteasome inhibitor-based drug combinations, we applied a hybrid experimental-computational approach, Quadratic Phenotypic Optimization Platform (QPOP) on a pool of nine drugs comprising proteasome inhibitors, kinase inhibitors and chemotherapy agents. QPOP utilizes small experimental drug response datasets to accurately identify globally optimal drug combinations. RESULTS: Preliminary drug screening highlighted the increased susceptibility of HCC PDXOs towards proteasome inhibitors. Through QPOP, the combination of second-generation proteasome inhibitor ixazomib (Ixa) and CDK inhibitor dinaciclib (Dina) was identified to be effective against HCC. In vitro and in vivo studies demonstrated the synergistic pro-apoptotic and anti-proliferative activity of Ixa + Dina against HCC PDXs and PDXOs. Furthermore, Ixa + Dina outperformed sorafenib in mitigating tumor formation in mice. Mechanistically, increased activation of JNK signaling mediates the combined anti-tumor effects of Ixa + Dina in HCC tumor cells. CONCLUSIONS: Rational drug combination design in patient-derived avatars highlights the therapeutic potential of proteasome and CDK inhibitors and represents a feasible approach towards developing more clinically relevant treatment strategies for HCC.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Antineoplásicos/farmacologia , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Combinação de Medicamentos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Complexo de Endopeptidases do Proteassoma , Inibidores de Proteassoma/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Sorafenibe/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Adv Ther (Weinh) ; 3(7): 2000034, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32838027

RESUMO

In 2019/2020, the emergence of coronavirus disease 2019 (COVID-19) resulted in rapid increases in infection rates as well as patient mortality. Treatment options addressing COVID-19 included drug repurposing, investigational therapies such as remdesivir, and vaccine development. Combination therapy based on drug repurposing is among the most widely pursued of these efforts. Multi-drug regimens are traditionally designed by selecting drugs based on their mechanism of action. This is followed by dose-finding to achieve drug synergy. This approach is widely-used for drug development and repurposing. Realizing synergistic combinations, however, is a substantially different outcome compared to globally optimizing combination therapy, which realizes the best possible treatment outcome by a set of candidate therapies and doses toward a disease indication. To address this challenge, the results of Project IDentif.AI (Identifying Infectious Disease Combination Therapy with Artificial Intelligence) are reported. An AI-based platform is used to interrogate a massive 12 drug/dose parameter space, rapidly identifying actionable combination therapies that optimally inhibit A549 lung cell infection by vesicular stomatitis virus within three days of project start. Importantly, a sevenfold difference in efficacy is observed between the top-ranked combination being optimally and sub-optimally dosed, demonstrating the critical importance of ideal drug and dose identification. This platform is disease indication and disease mechanism-agnostic, and potentially applicable to the systematic N-of-1 and population-wide design of highly efficacious and tolerable clinical regimens. This work also discusses key factors ranging from healthcare economics to global health policy that may serve to drive the broader deployment of this platform to address COVID-19 and future pandemics.

4.
Trends Biotechnol ; 38(5): 497-518, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31980301

RESUMO

Individualizing patient treatment is a core objective of the medical field. Reaching this objective has been elusive owing to the complex set of factors contributing to both disease and health; many factors, from genes to proteins, remain unknown in their role in human physiology. Accurately diagnosing, monitoring, and treating disorders requires advances in biomarker discovery, the subsequent development of accurate signatures that correspond with dynamic disease states, as well as therapeutic interventions that can be continuously optimized and modulated for dose and drug selection. This work highlights key breakthroughs in the development of enabling technologies that further the goal of personalized and precision medicine, and remaining challenges that, when addressed, may forge unprecedented capabilities in realizing truly individualized patient care.


Assuntos
Inteligência Artificial/tendências , Diagnóstico , Medicina de Precisão/tendências , Terapêutica/tendências , Biomarcadores/análise , Humanos
6.
Gastroenterology ; 157(6): 1615-1629.e17, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31446059

RESUMO

BACKGROUND & AIMS: Some oncogenes encode transcription factors, but few drugs have been successfully developed to block their activity specifically in cancer cells. The transcription factor SALL4 is aberrantly expressed in solid tumor and leukemia cells. We developed a screen to identify compounds that reduce the viability of liver cancer cells that express high levels of SALL4, and we investigated their mechanisms. METHODS: We developed a stringent high-throughput screening platform comprising unmodified SNU-387 and SNU-398 liver cancer cell lines and SNU-387 cell lines engineered to express low and high levels of SALL4. We screened 1597 pharmacologically active small molecules and 21,575 natural product extracts from plant, bacteria, and fungal sources for those that selectively reduce the viability of cells with high levels of SALL4 (SALL4hi cells). We compared gene expression patterns of SALL4hi cells vs SALL4-knockdown cells using RNA sequencing and real-time polymerase chain reaction analyses. Xenograft tumors were grown in NOD/SCID gamma mice from SALL4hi SNU-398 or HCC26.1 cells or from SALL4lo patient-derived xenograft (PDX) cells; mice were given injections of identified compounds or sorafenib, and the effects on tumor growth were measured. RESULTS: Our screening identified 1 small molecule (PI-103) and 4 natural compound analogues (oligomycin, efrapeptin, antimycin, and leucinostatin) that selectively reduced viability of SALL4hi cells. We performed validation studies, and 4 of these compounds were found to inhibit oxidative phosphorylation. The adenosine triphosphate (ATP) synthase inhibitor oligomycin reduced the viability of SALL4hi hepatocellular carcinoma and non-small-cell lung cancer cell lines with minimal effects on SALL4lo cells. Oligomycin also reduced the growth of xenograft tumors grown from SALL4hi SNU-398 or HCC26.1 cells to a greater extent than sorafenib, but oligomycin had little effect on tumors grown from SALL4lo PDX cells. Oligomycin was not toxic to mice. Analyses of chromatin immunoprecipitation sequencing data showed that SALL4 binds approximately 50% of mitochondrial genes, including many oxidative phosphorylation genes, to activate their transcription. In comparing SALL4hi and SALL4-knockdown cells, we found SALL4 to increase oxidative phosphorylation, oxygen consumption rate, mitochondrial membrane potential, and use of oxidative phosphorylation-related metabolites to generate ATP. CONCLUSIONS: In a screening for compounds that reduce the viability of cells that express high levels of the transcription factor SALL4, we identified inhibitors of oxidative phosphorylation, which slowed the growth of xenograft tumors from SALL4hi cells in mice. SALL4 activates the transcription of genes that regulate oxidative phosphorylation to increase oxygen consumption, mitochondrial membrane potential, and ATP generation in cancer cells. Inhibitors of oxidative phosphorylation might be used for the treatment of liver tumors with high levels of SALL4.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Neoplasias Hepáticas/tratamento farmacológico , Fatores de Transcrição/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Fosforilação Oxidativa/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
ACS Nano ; 9(7): 6644-54, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26115196

RESUMO

Due to their size and tailorable physicochemical properties, nanomaterials are an emerging class of structures utilized in biomedical applications. There are now many prominent examples of nanomaterials being used to improve human health, in areas ranging from imaging and diagnostics to therapeutics and regenerative medicine. An overview of these examples reveals several common areas of synergy and future challenges. This Nano Focus discusses the current status and future potential of promising nanomaterials and their translation from the laboratory to the clinic, by highlighting a handful of successful examples.


Assuntos
Nanomedicina/métodos , Pesquisa Translacional Biomédica , Nanomedicina/tendências
8.
J Lab Autom ; 19(6): 511-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24902713

RESUMO

Despite modern advances, a broad range of disorders such as cancer and infectious diseases continually afflict the global population. Novel therapeutics are continuously being explored to address these challenges. Therefore, scalable, effective, and safe therapies that are readily accessible to third-world countries are of major interest. In this article, we discuss the potential advantages that the nanomedicine field may harness toward successful implementation against some of the major diseases of our generation.


Assuntos
Testes Diagnósticos de Rotina/métodos , Saúde Global , Nanomedicina/métodos , Terapêutica/métodos , Humanos , Nanomedicina/tendências
9.
Adv Mater ; 25(26): 3532-41, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23584895

RESUMO

Self-assembled nanodiamond-lipid hybrid particles (NDLPs) harness the potent interaction between the nanodiamond (ND)-surface and small molecules, while providing a mechanism for cell-targeted imaging and therapy of triple negative breast cancers. Epidermal growth factor receptor-targeted NDLPs are highly biocompatible particles that provide cell-specific imaging, promote tumor retention of ND-complexes, prevent epirubicin toxicities and mediate regression of triple negative breast cancers.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Tolerância a Medicamentos , Lipídeos/química , Nanodiamantes/química , Animais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Feminino , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Nanoscale ; 3(7): 2844-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21617824

RESUMO

Recent reports have revealed that detonation nanodiamonds (NDs) can serve as efficient, biocompatible, and versatile drug delivery platforms. Consequently, further investigations exploring additional therapeutic applications are warranted. Current limitations associated with the non-specific nature of intravenous drugs limit the potential of certain pharmacological agents. One such treatment that could benefit from a stable delivery platform is antibody (Ab) therapy. Determination of Ab adsorption and desorption to a ND surface was subsequently examined using the transforming growth factor ß (TGF-ß) antibody as a model therapeutic. ND-Ab complexes were found to be stable in water through enzyme-linked immunosorbent assays (ELISAs), UV-vis spectroscopy and TEM, with no Ab released after ten days. Released Abs were detected in extreme pH solutions (3.5), DMEM (+) serum with pH levels ranging from 4 to 10.5, and inorganic saline solutions. Preserved activity of Abs released in DMEM (+) serum was confirmed using an ELISA. These results suggest ND-Ab complexes are synthesized and stabilized in water and are triggered to release active Abs upon exposure to physiological conditions.


Assuntos
Anticorpos/química , Nanodiamantes/química , Adsorção , Anticorpos/imunologia , Portadores de Fármacos/química , Ensaio de Imunoadsorção Enzimática , Concentração de Íons de Hidrogênio , Nanodiamantes/ultraestrutura , Espectrofotometria Ultravioleta , Fator de Crescimento Transformador beta/imunologia
12.
Hepatology ; 53(6): 2042-52, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21433044

RESUMO

UNLABELLED: Viral infections are often linked to altered drug metabolism in patients; however, the underlying molecular mechanisms remain unclear. Here we describe a mechanism by which activation of antiviral responses by the synthetic double-stranded RNA ligand, polyinosinic-polycytidylic acid (polyI:C), leads to decreased acetaminophen (APAP) metabolism and hepatotoxicity. PolyI:C administration down-regulates expression of retinoic X receptor-α (RXRα) as well as its heterodimeric partner pregnane X receptor (PXR) in mice. This down-regulation results in suppression of downstream cytochrome P450 enzymes involved in conversion of APAP to its toxic metabolite. Although the effects of polyI:C on drug metabolism are often attributed to interferon production, we report that polyI:C can decrease APAP metabolism in the absence of the type I interferon receptor. Furthermore, we demonstrate that polyI:C can attenuate APAP metabolism through both its membrane-bound receptor, Toll-like receptor 3 (TLR3), as well as cytoplasmic receptors. CONCLUSION: This is the first study to illustrate that in vivo administration of polyI:C affects drug metabolism independent of type I interferon production or in the absence of TLR3 through crosstalk between nuclear receptors and antiviral responses.


Assuntos
Acetaminofen/efeitos adversos , Antivirais/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Interferon Tipo I/metabolismo , Poli I-C/uso terapêutico , Receptor 3 Toll-Like/metabolismo , Acetaminofen/metabolismo , Animais , Antivirais/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Sinergismo Farmacológico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Poli I-C/farmacologia , Receptor de Pregnano X , RNA de Cadeia Dupla/farmacologia , RNA Viral/genética , Receptores de Esteroides/metabolismo , Receptor X Retinoide alfa/metabolismo , Xenobióticos/farmacologia , Xenobióticos/uso terapêutico
13.
Sci Transl Med ; 3(73): 73ra21, 2011 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21389265

RESUMO

Enhancing chemotherapeutic efficiency through improved drug delivery would facilitate treatment of chemoresistant cancers, such as recurrent mammary tumors and liver cancer. One way to improve drug delivery is through the use of nanodiamond (ND) therapies, which are both scalable and biocompatible. Here, we examined the efficacy of an ND-conjugated chemotherapeutic in mouse models of liver and mammary cancer. A complex (NDX) of ND and doxorubicin (Dox) overcame drug efflux and significantly increased apoptosis and tumor growth inhibition beyond conventional Dox treatment in both murine liver tumor and mammary carcinoma models. Unmodified Dox treatment represents the clinical standard for most cancer treatment regimens, and NDX had significantly decreased toxicity in vivo compared to standard Dox treatment. Thus, ND-conjugated chemotherapy represents a promising, biocompatible strategy for overcoming chemoresistance and enhancing chemotherapy efficacy and safety.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos , Nanoestruturas , Neoplasias Experimentais/tratamento farmacológico , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Diamante , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Nanomedicina , Nanotecnologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
14.
J Clin Invest ; 119(7): 1910-20, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19487810

RESUMO

Influenza-related complications continue to be a major cause of mortality worldwide. Due to unclear mechanisms, a substantial number of influenza-related deaths result from bacterial superinfections, particularly secondary pneumococcal pneumonia. Here, we report what we believe to be a novel mechanism by which influenza-induced type I IFNs sensitize hosts to secondary bacterial infections. Influenza-infected mice deficient for type I IFN-alpha/beta receptor signaling (Ifnar-/- mice) had improved survival and clearance of secondary Streptococcus pneumoniae infection from the lungs and blood, as compared with similarly infected wild-type animals. The less effective response in wild-type mice seemed to be attributable to impaired production of neutrophil chemoattractants KC (also known as Cxcl1) and Mip2 (also known as Cxcl2) following secondary challenge with S. pneumoniae. This resulted in inadequate neutrophil responses during the early phase of host defense against secondary bacterial infection. Indeed, influenza-infected wild-type mice cleared secondary pneumococcal pneumonia after pulmonary administration of exogenous KC and Mip2, whereas neutralization of Cxcr2, the common receptor for KC and Mip2, reversed the protective phenotype observed in Ifnar-/- mice. These data may underscore the importance of the type I IFN inhibitory pathway on CXC chemokine production. Collectively, these findings highlight what we believe to be a novel mechanism by which the antiviral response to influenza sensitizes hosts to secondary bacterial pneumonia.


Assuntos
Interferon Tipo I/fisiologia , Infecções por Orthomyxoviridae/complicações , Pneumonia Pneumocócica/etiologia , Animais , Quimiocina CXCL1/análise , Quimiocina CXCL1/fisiologia , Quimiocina CXCL2/análise , Quimiocina CXCL2/fisiologia , Interleucina-10/fisiologia , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/fisiologia
15.
J Exp Med ; 203(12): 2589-602, 2006 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-17074929

RESUMO

Viral infections and antiviral responses have been linked to several metabolic diseases, including Reye's syndrome, which is aspirin-induced hepatotoxicity in the context of a viral infection. We identify an interferon regulatory factor 3 (IRF3)-dependent but type I interferon-independent pathway that strongly inhibits the expression of retinoid X receptor alpha (RXRalpha) and suppresses the induction of its downstream target genes, including those involved in hepatic detoxification. Activation of IRF3 by viral infection in vivo greatly enhances bile acid- and aspirin-induced hepatotoxicity. Our results provide a critical link between the innate immune response and host metabolism, identifying IRF3-mediated down-regulation of RXRalpha as a molecular mechanism for pathogen-associated metabolic diseases.


Assuntos
Regulação para Baixo/imunologia , Regulação Viral da Expressão Gênica/imunologia , Hepatite Viral Animal/metabolismo , Fator Regulador 3 de Interferon/fisiologia , Receptor X Retinoide alfa/antagonistas & inibidores , Animais , Células Cultivadas , Regulação para Baixo/genética , Hepatite Viral Animal/genética , Hepatite Viral Animal/imunologia , Camundongos , Camundongos Knockout , Receptor X Retinoide alfa/biossíntese , Receptor X Retinoide alfa/genética , Síndrome de Reye/genética , Síndrome de Reye/imunologia , Síndrome de Reye/virologia , Infecções por Rhabdoviridae/genética , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/metabolismo , Vírus da Estomatite Vesicular Indiana/imunologia
16.
EMBO J ; 24(23): 4071-81, 2005 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-16308570

RESUMO

Transforming growth factor-beta (TGF-beta) and type I interferon (IFN) autocrine/paracrine loops are recognized as key mediators of signaling cascades that control a variety of cellular functions. Here, we describe a novel mechanism by which Toll-like receptor (TLR) agonists utilize these two autocrine/paracrine loops to differentially regulate the induction of PDGF-B, a growth factor implicated in a number of diseases ranging from tumor metastasis to glomerulonephritis. We demonstrate that CpG-specific induction of PDGF-B requires activation of Smads through TGFbeta1 autocrine/paracrine signaling. In contrast, polyinosinic:polycytidylic acid strongly represses CpG's as well as its own intrinsic ability to induce PDGF-B mRNA through type I IFN-mediated induction of Smad7, a negative regulator of Smad3/4. Furthermore, we have shown that this crosstalk mechanism translates into similar regulation of mesangial cell proliferation. Thus, our results demonstrate the importance of crosstalk between TGF-beta and type I IFNs in determining the specificity of TLR-mediated gene induction.


Assuntos
Interferon Tipo I/fisiologia , Proteínas Proto-Oncogênicas c-sis/biossíntese , Transdução de Sinais/fisiologia , Receptores Toll-Like/agonistas , Fator de Crescimento Transformador beta/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Animais , Antígenos de Diferenciação/fisiologia , Linhagem Celular , Proliferação de Células , Células Cultivadas , Ilhas de CpG/fisiologia , Quinases Associadas a Receptores de Interleucina-1 , Células Mesangiais/citologia , Células Mesangiais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide , NF-kappa B/fisiologia , Fosfotransferases (Aceptor do Grupo Álcool)/fisiologia , Poli I-C/metabolismo , RNA Mensageiro/metabolismo , Receptores Imunológicos/fisiologia , Proteína Smad4/metabolismo , Proteína Smad7/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Regulação para Cima
17.
J Exp Med ; 199(12): 1651-8, 2004 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-15210743

RESUMO

TANK-binding kinase-1 (TBK1) and the inducible IkappaB kinase (IKK-i) have been shown recently to activate interferon (IFN) regulatory factor-3 (IRF3), the primary transcription factor regulating induction of type I IFNs. Here, we have compared the role and specificity of TBK1 in the type I IFN response to lipopolysaccharide (LPS), polyI:C, and viral challenge by examining IRF3 nuclear translocation, signal transducer and activator of transcription 1 phosphorylation, and induction of IFN-regulated genes. The LPS and polyI:C-induced IFN responses were abolished and delayed, respectively, in macrophages from mice with a targeted disruption of the TBK1 gene. When challenged with Sendai virus, the IFN response was normal in TBK1(-/-) macrophages, but defective in TBK1(-/-) embryonic fibroblasts. Although both TBK1 and IKK-i are expressed in macrophages, only TBK1 but not IKK-i was detected in embryonic fibroblasts by Northern blotting analysis. Furthermore, the IFN response in TBK1(-/-) embryonic fibroblasts can be restored by reconstitution with wild-type IKK-i but not a mutant IKK-i lacking kinase activity. Thus, our studies suggest that TBK1 plays an important role in the Toll-like receptor-mediated IFN response and is redundant with IKK-i in the response of certain cell types to viral infection.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Interferon Tipo I/imunologia , Glicoproteínas de Membrana/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/imunologia , Fatores de Transcrição/fisiologia , Viroses/imunologia , Animais , Antígenos CD/imunologia , Antígenos CD/fisiologia , Fator Regulador 3 de Interferon , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Knockout , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , RNA de Cadeia Dupla/genética , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/imunologia , Receptores do Fator de Necrose Tumoral/fisiologia , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Toll-Like
18.
J Exp Med ; 199(1): 81-90, 2004 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-14699082

RESUMO

Toll-like receptor (TLR) signaling and phagocytosis are hallmarks of macrophage-mediated innate immune responses to bacterial infection. However, the relationship between these two processes is not well established. Our data indicate that TLR ligands specifically promote bacterial phagocytosis, in both murine and human cells, through induction of a phagocytic gene program. Importantly, TLR-induced phagocytosis of bacteria was found to be reliant on myeloid differentiation factor 88-dependent signaling through interleukin-1 receptor-associated kinase-4 and p38 leading to the up-regulation of scavenger receptors. Interestingly, individual TLRs promote phagocytosis to varying degrees with TLR9 being the strongest and TLR3 being the weakest inducer of this process. We also demonstrate that TLR ligands not only amplify the percentage of phagocytes uptaking Escherichia coli, but also increase the number of bacteria phagocytosed by individual macrophages. Taken together, our data describe an evolutionarily conserved mechanism by which TLRs can specifically promote phagocytic clearance of bacteria during infection.


Assuntos
Glicoproteínas de Membrana/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fagocitose/genética , Receptores de Superfície Celular/genética , Animais , Infecções Bacterianas/imunologia , Sequência de Bases , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Primers do DNA , Escherichia coli/fisiologia , Humanos , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/fisiologia , Camundongos , Receptor 3 Toll-Like , Receptor Toll-Like 9 , Receptores Toll-Like , Proteínas Quinases p38 Ativadas por Mitógeno
19.
J Immunol ; 170(7): 3565-71, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12646618

RESUMO

We have recently described an IFN regulatory factor 3-mediated antiviral gene program that is induced by both Toll-like receptor (TLR)3 and TLR4 ligands. In our current study, we show that activation of IFN/viral response gene expression in primary macrophage cells is stronger and prolonged with TLR3 stimulation compared with that of TLR4. Our data also reveal that the cytoplasmic tails of both TLR3 and TLR4 can directly interact with myeloid differentiation factor 88 (MyD88). However, although Toll/IL-1 receptor homology domain-containing adaptor protein/MyD88 adaptor-like is able to associate with TLR4, we were unable to detect any interaction between Toll/IL-1 receptor homology domain-containing adaptor protein/MyD88 adaptor-like and TLR3. By using quantitative real-time PCR assays, we found that TLR3 expression is inducible by both TLR3 and TLR4 ligands, while TLR4 expression is not inducible by these same stimuli. Furthermore, using cells derived from mice deficient in the IFN-alphabetaR, we show that both TLR3 and TLR4 require IFN-beta autocrine/paracrine feedback to induce TLR3 expression and activate/enhance genes required for antiviral activity. More specifically, a subset of antiviral genes is initially induced independent of IFN-beta, yet the cytokine further enhances expression at later time points. This was in contrast to a second set of genes (including TLR3) that is induced only after IFN-beta production. Taken together, our data argue that, despite both TLR3 and TLR4 being able to use IFN-beta to activate/enhance antiviral gene expression, TLR3 uses multiple mechanisms to enhance and sustain the antiviral response more strongly than TLR4.


Assuntos
Antivirais/fisiologia , Glicoproteínas de Membrana/fisiologia , Receptores de Superfície Celular/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/fisiologia , Animais , Antígenos de Diferenciação/biossíntese , Antígenos de Diferenciação/metabolismo , Antivirais/genética , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Gammaherpesvirinae/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Interferon-alfa/metabolismo , Interferon beta/biossíntese , Interferon beta/genética , Interferon beta/metabolismo , Interferon beta/fisiologia , Ligantes , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide , Receptor de Interferon alfa e beta , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/metabolismo , Receptores Imunológicos/biossíntese , Receptores Imunológicos/metabolismo , Receptores de Interferon/fisiologia , Receptores de Interleucina-1/biossíntese , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/fisiologia , Fator de Transcrição STAT1 , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptor 3 Toll-Like , Receptor 4 Toll-Like , Receptores Toll-Like , Transativadores/metabolismo
20.
J Am Soc Echocardiogr ; 15(9): 997-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12221420

RESUMO

We report a case of partial anomalous pulmonary venous drainage where the left upper and lower pulmonary veins drain into a separate posterior left atrial (LA) chamber before continuing as a vertical ascending vein. The vertical vein then joins the left innominate vein, which eventually drains into a normal right-sided superior vena cava. There was no fenestration or communication between this posterior chamber and the true LA. The true LA contained the fossa ovale and LA appendage. The right upper and lower pulmonary veins drain normally into the true LA. To our knowledge, this is the first case where the left upper and lower pulmonary veins drain into a separate posterior LA chamber before continuing into a vertical vein. The diagnosis was initially made with transesophageal echocardiography and confirmed by magnetic resonance imaging. The patient later underwent successful corrective operation.


Assuntos
Veias Pulmonares/anormalidades , Adulto , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Cardiopatias Congênitas/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/patologia
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