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1.
Cancer Sci ; 109(3): 832-842, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29285847

RESUMO

Lung cancer is the leading cause of cancer-related death worldwide. Thus, developing novel therapeutic agents has become critical for lung cancer treatment. In this study, compound AS7128 was selected from a 2-million entry chemical library screening and identified as a candidate drug against non-small cell lung cancer in vitro and in vivo. Further investigation indicated that AS7128 could induce cell apoptosis and cell cycle arrest, especially in the mitosis stage. In addition, we also found that iASPP, an oncogenic protein that functionally inhibits p53, might be associated with AS7128 through mass identification. Further exploration indicated that AS7128 treatment could restore the transactivation ability of p53 and, thus, increase the expressions of its downstream target genes, which are related to cell cycle arrest and apoptosis. This occurs through disruption of the interactions between p53 and iASPP in cells. Taken together, AS7128 could bind to iASPP, disrupt the interaction between iASPP and p53, and result in cell cycle arrest and apoptosis. These findings may provide new insight for using iASPP as a therapeutic target for non-small cell lung cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Repressoras/metabolismo , Tiazóis/administração & dosagem , Proteína Supressora de Tumor p53/metabolismo , Células A549 , Animais , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Ligação Proteica/efeitos dos fármacos , Tiazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Int J Mol Sci ; 18(12)2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215575

RESUMO

Effective DNA repair enables cancer cells to survive DNA damage induced by chemotherapeutic or radiotherapeutic treatments. Therefore, inhibiting DNA repair pathways is a promising therapeutic strategy for increasing the efficacy of such treatments. In this study, we found that dihydrocoumarin (DHC), a flavoring agent, causes deficiencies in double-stand break (DSB) repair and prolonged DNA damage checkpoint recovery in yeast. Following DNA damage, Rad52 recombinase was revealed to be inhibited by DHC, which results in deficiencies in DSB repair and prolonged DNA damage checkpoint recovery. The deletion of RPD3, a class I histone deacetylase (HDAC), was found to mimic DHC-induced suppression of Rad52 expression, suggesting that the HDAC inhibitor activity of DHC is critical to DSB repair and DNA damage sensitivity. Overall, our findings delineate the regulatory mechanisms of DHC in DSB repair and suggest that it might potentially be used as an inhibitor of the DNA repair pathway in human cells.


Assuntos
Cumarínicos/toxicidade , Dano ao DNA , Aromatizantes/toxicidade , Inibidores de Histona Desacetilases/toxicidade , Proteína Rad52 de Recombinação e Reparo de DNA/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Cumarínicos/farmacologia , Aromatizantes/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Reparo de DNA por Recombinação , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
3.
Am J Respir Crit Care Med ; 190(4): 433-44, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25036006

RESUMO

RATIONALE: Despite advances in treatment and prognosis of non-small cell lung cancer (NSCLC), patient outcomes are still unsatisfactory. OBJECTIVES: To reduce the morbidity and mortality of patients with NSCLC, a more comprehensive understanding of mechanisms involved in cancer progression is urgently needed. METHODS: By comparison of gene expression profiles in the cell line pair with differential invasion ability, CL1-0 and CL1-5, we found that Shisa3 was highly expressed in the low invasive cells. The effect of Shisa3 on invasion, migration, proliferation, apoptosis, epithelial-mesenchymal transition, and anchorage-independent growth activities in vitro and on tumor growth and metastasis in mice models were examined. The underlying mechanism of Shisa3 was explored by microarray and pathway analysis. Finally, the correlation of Shisa3 expression and clinical outcome was also calculated. MEASUREMENTS AND MAIN RESULTS: We identified Shisa3 as a novel tumor suppressor, which induces ß-catenin degradation resulting in suppression of tumorigenesis and invasion in vitro. Shisa3 decreased the tumor growth in mice with subcutaneous implantation and reduced the number of metastatic nodules in mice with tail vein injection and orthotopic implantation. Shisa3 performs the tumor suppression activity through WNT signaling predicted by microarray analysis. Our data found that Shisa3 accelerates ß-catenin degradation and was positively associated with overall survival and progression-free survival of NSCLC. CONCLUSIONS: Our results reveal that Shisa3 acts as a tumor suppressor by acceleration of ß-catenin degradation and provide new insight for cancer prognosis and therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/metabolismo , beta Catenina/metabolismo , Idoso , Animais , Apoptose/genética , Western Blotting/métodos , Carcinoma Pulmonar de Células não Pequenas/genética , Movimento Celular/genética , Proliferação de Células , Sobrevivência Celular/genética , Modelos Animais de Doenças , Humanos , Técnicas In Vitro , Neoplasias Pulmonares/genética , Proteínas de Membrana/genética , Camundongos , Camundongos SCID , Análise em Microsséries/métodos , Reação em Cadeia da Polimerase/métodos , Transdução de Sinais/genética , Taiwan , Células Tumorais Cultivadas , beta Catenina/genética
4.
Sci Rep ; 14(1): 19374, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169058

RESUMO

The 5-year survival is poor for stage IV non-small cell lung cancer (NSCLC). Recently, cell immunotherapy has emerged as a new treatment strategy. This study aimed to evaluate the efficacy and safety of Immune killer cells (IKC) in patients with stage IV NSCLC after the failure of prior chemotherapy. This study enrolled 26 patients with stage IV NSCLC who failed at least two lines of chemotherapy with or without targeted therapy. The IKC was given alone weekly for 24 weeks. The primary endpoint was progression-free survival (PFS). Secondary outcomes included overall survival (OS), pain intensity, quality of life (QOL), and safety. The median PFS for the intent-to-treat (ITT) population (i.e., all enrolled patients) was 3.8 month. In the per-protocol (PP) population (i.e., patients receiving > 12 IKC infusions), the median PFS was 5.6 months. Moreover, the ITT population showed a 1-year survival rate of 60.0%, while that for the PP population was 85.7%. Only 7 out of 200 AEs (3.5%) were related to the IKC infusion, and they were all rated as grade 1 in severity. The IKC infusion was well tolerated. This novel immunotherapy prolonged the PFS and improved the survival compared with historical data. It might be a potential treatment strategy for stage IV NSCLC patient who failed prior chemotherapy.ClinicalTrials.gov identifier: NCT03499834.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Estadiamento de Neoplasias , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Idoso , Qualidade de Vida , Intervalo Livre de Progressão , Adulto , Resultado do Tratamento , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/efeitos adversos
5.
Nat Commun ; 13(1): 1238, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264584

RESUMO

In the long history of traditional Chinese medicine, single herbs and complex formulas have been suggested to increase lifespan. However, the identification of single molecules responsible for lifespan extension has been challenging. Here, we collected a list of traditional Chinese medicines with potential longevity properties from pharmacopeias. By utilizing the mother enrichment program, we systematically screened these traditional Chinese medicines and identified a single herb, Psoralea corylifolia, that increases lifespan in Saccharomyces cerevisiae. Next, twenty-two pure compounds were isolated from Psoralea corylifolia. One of the compounds, corylin, was found to extend the replicative lifespan in yeast by targeting the Gtr1 protein. In human umbilical vein endothelial cells, RNA sequencing data showed that corylin ameliorates cellular senescence. We also examined an in vivo mammalian model, and found that corylin extends lifespan in mice fed a high-fat diet. Taken together, these findings suggest that corylin may promote longevity.


Assuntos
Células Endoteliais , Longevidade , Animais , Flavonoides/farmacologia , Mamíferos , Medicina Tradicional Chinesa , Camundongos
6.
Antioxidants (Basel) ; 9(4)2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32218307

RESUMO

Atherosclerosis is a complex disease that includes several events, including reactive oxygen species (ROS) stress, inflammation, endothelial dysfunction, lipid deposition, and vascular smooth muscle cell (VSMC) proliferation and migration, which result in atherosclerotic plaque formation. Corylin, a flavonoid compound, is known to exhibit antioxidative, anti-inflammatory and antiproliferative effects. However, it remains unknown whether corylin could modulate atherogenesis. Here, we identified the anti-inflammatory effect of corylin in tumor necrosis factor-α (TNF-α)-induced vascular cells. In human umbilical vein endothelial cells (HUVECs), corylin suppressed TNF-α-induced monocyte adhesion to the HUVECs and transmigration by downregulating the ROS/JNK/nuclear factor-kappa beta (NF-κB) p65 pathway. In VSMCs, corylin inhibited TNF-α-induced monocyte adhesion by suppressing ROS production, mitogen-activated protein kinase (MAPK) phosphorylation and NF-κB p65 translocation. In platelet-derived growth factor-BB (PDGF-BB)-induced VSMCs, corylin inhibited PDGF-BB-induced VSMC proliferation and migration through regulating the mammalian target of rapamycin (mTOR)/dynamin-1-like protein 1 (Drp1) signaling cascade. In addition, corylin treatment not only attenuated atherosclerotic lesions, ROS production, vascular cell adhesion protein-1 (VCAM-1) expression, monocyte adhesion and VSMC proliferation in apolipoprotein E (ApoE)-deficient mice but also inhibited neointimal hyperplasia in endothelial-denuded mice. Thus, corylin may be a potential prevention and treatment for atherosclerosis.

7.
J Med Chem ; 63(6): 3172-3187, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32125853

RESUMO

Drug resistance has been a major threat in cancer therapies that necessitates the development of new strategies to overcome this problem. We report here a cell-based high-throughput screen of a library containing two-million molecules for the compounds that inhibit the proliferation of non-small-cell lung cancer (NSCLC). Through the process of phenotypic screening, target deconvolution, and structure-activity relationship (SAR) analysis, a compound of furanonaphthoquinone-based small molecule, AS4583, was identified that exhibited potent activity in tyrosine kinase inhibitor (TKI)-sensitive and TKI-resistant NSCLC cells (IC50 = 77 nM) and in xenograft mice. The mechanistic studies revealed that AS4583 inhibited cell-cycle progression and reduced DNA replication by disrupting the formation of the minichromosomal maintenance protein (MCM) complex. Subsequent SAR study of AS4583 gave compound RJ-LC-07-48 which exhibited greater potency in drug-resistant NSCLC cells (IC50 = 17 nM) and in mice with H1975 xenograft tumor.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Furanos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Manutenção de Minicromossomo/metabolismo , Naftoquinonas/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/uso terapêutico , Furanos/síntese química , Furanos/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Molecular , Naftoquinonas/síntese química , Naftoquinonas/metabolismo , Ligação Proteica , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Cancers (Basel) ; 11(12)2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31847356

RESUMO

Metastasis is a predominant cause of cancer death and the major challenge in treating lung adenocarcinoma (LADC). Therefore, exploring new metastasis-related genes and their action mechanisms may provide new insights for developing a new combative approach to treat lung cancer. Previously, our research team discovered that the expression of the inhibitor of DNA binding 4 (Id4) was inversely related to cell invasiveness in LADC cells by cDNA microarray screening. However, the functional role of Id4 and its mechanism of action in lung cancer metastasis remain unclear. In this study, we report that the expression of Id4 could attenuate cell migration and invasion in vitro and cancer metastasis in vivo. Detailed analyses indicated that Id4 could promote E-cadherin expression through the binding of Slug, cause the occurrence of mesenchymal-epithelial transition (MET), and inhibit cancer metastasis. Moreover, the examination of the gene expression database (GSE31210) also revealed that high-level expression of Id4/E-cadherin and low-level expression of Slug were associated with a better clinical outcome in LADC patients. In summary, Id4 may act as a metastatic suppressor, which could not only be used as an independent predictor but also serve as a potential therapeutic for LADC treatment.

9.
J Med Chem ; 59(18): 8521-34, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27536893

RESUMO

Microtubule targeting agents (MTAs) constitute a class of drugs for cancer treatment. Despite many MTAs have been proven to significantly improve the treatment outcomes of various malignancies, resistance has usually occurred. By selection from a two million entry chemical library based on the efficacy and safety, we identified purine-type compounds that were active against lung small cell lung cancer (NSCLC). The purine compound 5a (GRC0321) was an MTA with good effects against NSCLC. Lung cancer cells H1975 treated with 5a could induce microtubule fragmentation, leading to G2/M cell cycle arrest and intrinsic apoptosis. Compound 5a directly targeted katanin and regulated the severing activity of katanin, which cut the cellular microtubules into short pieces and activated c-Jun N-terminal kinases (JNK). The microtubule fragmenting effect of 5a is a unique mechanism in MTAs. It might overcome the resistance problems that most of the MTAs have faced.


Assuntos
Adenosina Trifosfatases/metabolismo , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Microtúbulos/efeitos dos fármacos , Purinas/farmacologia , Antineoplásicos/química , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Katanina , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Microtúbulos/metabolismo , Microtúbulos/patologia , Purinas/química
10.
Stem Cell Reports ; 1(2): 139-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24052949

RESUMO

Mesenchymal stromal cells (MSCs) are multilineage progenitors with immunomodulatory properties, including expansion of immunomodulatory leukocytes such as regulatory T lymphocytes (Tregs) and tolerogenic dendritic cells. We report that human MSCs can expand CD14(-)CD11b(+)CD33(+) human myeloid-derived suppressor cells (MDSCs). MSC-expanded MDSCs suppress allogeneic lymphocyte proliferation, express arginase-1 and inducible nitric oxide synthase, and increase the number of Tregs. This expansion occurs through the secretion of hepatocyte growth factor (HGF), with effects replicated by adding HGF singly and abrogated by HGF knockdown in MSCs. In wild-type mice, the liver, which secretes high levels of HGF, contains high numbers of Gr-1(+)CD11b(+) MDSCs, and injection of HGF into mice significantly increases the number of MDSCs. Expansion of MDSCs by MSC-secreted HGF involves c-Met (its receptor) and downstream phosphorylation of STAT3, a key factor in MDSC expansion. Our data further support the strong immunomodulatory nature of MSCs and demonstrate the role of HGF, a mitogenic molecule, in the expansion of MDSCs.


Assuntos
Fator de Crescimento de Hepatócito/metabolismo , Fígado/citologia , Células-Tronco Mesenquimais/imunologia , Células Mieloides/imunologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Antígenos CD/metabolismo , Células da Medula Óssea/metabolismo , Células Cultivadas , Feminino , Técnicas de Silenciamento de Genes , Fator de Crescimento de Hepatócito/genética , Humanos , Fígado/imunologia , Fígado/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos , Células Mieloides/metabolismo , Placenta/citologia , Gravidez , Linfócitos T Reguladores/metabolismo
11.
Cell Transplant ; 20(11-12): 1721-30, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21669042

RESUMO

Interactions between maternal natural killer lymphocytes (NKs) and fetal tissues are important in mediating maternal-fetal tolerance. We therefore investigated the interactions of NKs to placenta-derived multipotent cells (PDMCs) isolated from the term human placenta. PDMCs have similar cell surface marker expression as bone marrow mesenchymal stem cells (BMMSCs) and additionally express human embryonic stem cell markers SSEA-4 and CD-9. Differentiation into the tri-mesodermal lineages of osteoblastic, adipocytic, and chondrogenic phenotypes can be readily achieved under the appropriate conditions. We found that PDMCs are more resistant to NK-mediated lysis than the major histocompatibility complex (MHC) class-I null target cell K562, and can suppress NK secretion of interferon-γ (IFN-γ). Moreover, as third-party cells, PDMCs suppressed the cytotoxic effects of cytokine-stimulated NKs on K562. Pretreatment of PDMCs with IFN-γ, a proinflammatory cytokine, surprisingly enhanced such immunosuppressive effects. Cell-cell contact between NKs and PDMCs is required for suppressive effects, which are partially mediated by slight upregulation of the NK inhibitory receptor killer inhibitory receptor and downregulation of the activating receptor NKp30. Moreover, enhancement of PDMC suppressive effects is also mediated by IFN-γ-induced surface expression of HLA-G--an immunomodulatory nonclassical MHC class I molecule--on PDMCs, as seen by partial reversibility with HLA-G neutralizing antibodies. With its broad immunosuppressive properties, PDMCs may represent a potential cell source for therapeutic use.


Assuntos
Antígenos HLA-G/metabolismo , Células Matadoras Naturais/imunologia , Células-Tronco Multipotentes/metabolismo , Placenta/citologia , Diferenciação Celular , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Feminino , Antígenos HLA-G/imunologia , Humanos , Terapia de Imunossupressão , Interferon gama/farmacologia , Interleucina-2/farmacologia , Células K562 , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/imunologia , Receptor 3 Desencadeador da Citotoxicidade Natural/metabolismo , Gravidez , Receptores de Superfície Celular/metabolismo
12.
Exp Cell Res ; 314(3): 421-9, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18164704

RESUMO

Angiogenesis, the process of new blood vessel formation, is important in wound healing, inflammation, tumorigenesis and metastases. During this process, it is a critical step of the loosening of cellular interactions between endothelial cells, which are dependent on the architecture of adherens junction constructed by homophilic interactions of cell surface cadherins. Several studies suggested that the dynamic changes of cadherins are necessary during angiogenesis. However, the mechanism of cadherins regulation on endothelial cells requires further delineation. Here, we showed that basic fibroblast growth factor (bFGF), a pivotal pro-angiogenic factor, can downregulate typical cadherins (E-, N-, P- and VE-cadherin) expression on the surface of human umbilical vein endothelial cells (HUVECs) via FGF receptor 1 (FGFR1) signaling. The bFGF-mediated surface cadherin downregulation was significantly reversed only when the HUVECs were treated with JNK inhibitor (SP600125), but not ERK (PD98059) or p38 inhibitor (SB203580). Infecting HUVECs with a dominant negative H-Ras mutant (Ras(S17N)) interferes bFGF-mediated cadherin downregulation, and the result suggests that bFGF attenuates surface cadherin expression on HUVECs via FGFR1 and intracellular Ras-JNK signaling. However, after growth factors withdrawal, FGFR1 blockade or JNK inhibition for 16 h, cadherins were re-expressed on cell surface of HUVECs. But the mRNA or total protein of cadherins had no significant change, suggesting that the effect of bFGF on cadherin expression may work through a post-translational control. Our data first suggest that JNK participates in bFGF-mediated surface cadherin downregulation. Loss of surface cadherins may affect the cell-cell interaction between endothelial cells and facilitate angiogenesis.


Assuntos
Junções Aderentes/metabolismo , Caderinas/metabolismo , Endotélio Vascular/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neovascularização Fisiológica/fisiologia , Junções Aderentes/efeitos dos fármacos , Junções Aderentes/ultraestrutura , Antracenos/farmacologia , Caderinas/genética , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Comunicação Celular/fisiologia , Células Cultivadas , Regulação para Baixo/fisiologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/ultraestrutura , Inibidores Enzimáticos/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Recém-Nascido , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/fisiologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/agonistas , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Fatores ras de Troca de Nucleotídeo Guanina/genética
13.
Diabetes ; 57(7): 1861-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18420489

RESUMO

OBJECTIVE: Coinhibitory signals mediated via programmed death 1 (PD-1) receptor play a critical role in downregulating immune responses and in maintaining peripheral tolerance. Programmed death 1 ligand 1 (PD-L1), the interacting ligand for PD-1, widely expressed in many cell types, acts as a tissue-specific negative regulator of pathogenic T-cell responses. We investigated the protective potential of PD-L1 on autoimmune diabetes by transgenically overexpressing PD-L1 in pancreatic beta-cells in nonobese diabetic (NOD) mice. RESEARCH DESIGN AND METHODS: We established an insulin promoter-driven murine PD-L1 transgenic NOD mouse model to directly evaluate the protective effect of an organ-specific PD-L1 transgene against autoimmune diabetes. Transgene expression, insulitis, and diabetic incidence were characterized in these transgenic NOD mice. Lymphocyte development, Th1 cells, and regulatory T-cells were analyzed in these transgenic mice; and T-cell proliferation, adoptive transfer, and islet transplantation were performed to evaluate the PD-L1 transgene-mediated immune-protective mechanisms. RESULTS: The severity of insulitis in these transgenic mice is significantly decreased, disease onset is delayed, and the incidence of diabetes is markedly decreased compared with littermate controls. NOD/SCID mice that received lymphocytes from transgenic mice became diabetic at a slower rate than mice receiving control lymphocytes. Moreover, lymphocytes collected from recipients transferred by lymphocytes from transgenic mice revealed less proliferative potential than lymphocytes obtained from control recipients. Transgenic islets transplanted in diabetic recipients survived moderately longer than control islets. CONCLUSIONS: Our results demonstrate the protective potential of transgenic PD-L1 in autoimmune diabetes and illustrate its role in downregulating diabetogenic T-cells in NOD mice.


Assuntos
Antígeno B7-1/genética , Diabetes Mellitus Tipo 1/imunologia , Glicoproteínas de Membrana/genética , Peptídeos/genética , Transferência Adotiva , Animais , Antígeno B7-1/análise , Antígeno B7-1/fisiologia , Antígeno B7-H1 , Divisão Celular , Clonagem Molecular , Diabetes Mellitus Tipo 1/patologia , Feminino , Hiperinsulinismo/imunologia , Hiperinsulinismo/patologia , Linfonodos/imunologia , Linfonodos/patologia , Ativação Linfocitária , Masculino , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos NOD/genética , Camundongos SCID , Camundongos Transgênicos , Pâncreas/patologia , Peptídeos/análise , Peptídeos/fisiologia , Plasmídeos , Reação em Cadeia da Polimerase , Transdução de Sinais , Linfócitos T/imunologia
14.
Clin Sci (Lond) ; 111(4): 253-63, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16623660

RESUMO

To investigate the kinetic Th1/Th2 immunopathogenic mechanisms of Haemophilus influenzae meningitis, we established a murine experimental model of meningitis and elucidated the Th1/Th2 immune responses in T1/T2 doubly transgenic mice based on a BALB/c background under the control of the IFN-gamma (interferon-gamma)/IL-4 (interleukin-4) promoters respectively. NTHi (non-typeable Haemophilus influenzae) meningitis was induced in these mice by inoculation with either a colonized (CNTHi) or invasive (INTHi) strain of NTHi. Mice inoculated with CNTHi displayed a less severe degree of disease in terms of clinical symptoms, mortality rate and brain histopathology. Conversely, INTHi-inoculated mice had more severe clinical symptoms. CNTHi-inoculated mice had a more significant Th1 response in terms of a higher percentage and longer maintenance of Th1 cells, and more production of IFN-gamma from strain-specific antigen-stimulated splenocytes than INTHi-inoculated mice. In contrast, INTHi-inoculated mice had a more significant Th2 response. This was due to a significant increase in IL-4-producing CD4(+) T-cells (Th2 cells) and more production of IL-4 from strain-specific antigen-stimulated splenocytes accompanied by a rapid decline of Th1 cells in INTHi-inoculated mice. In conclusion, the preferential Th1/Th2 trend in this murine model of NTHi meningitis is correlated with clinical severity as well as isolated characteristics of the pathogens themselves.


Assuntos
Haemophilus influenzae , Meningite por Haemophilus/imunologia , Células Th1/imunologia , Células Th2/imunologia , Doença Aguda , Animais , Antígenos de Bactérias/imunologia , Encéfalo/patologia , Proliferação de Células , Células Cultivadas , Citocinas/biossíntese , Modelos Animais de Doenças , Haemophilus influenzae/imunologia , Subpopulações de Linfócitos/imunologia , Meningite por Haemophilus/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Índice de Gravidade de Doença , Especificidade da Espécie , Baço/imunologia
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