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1.
Oncogene ; 37(8): 1005-1019, 2018 02 22.
Article in English | MEDLINE | ID: mdl-29084210

ABSTRACT

During normal tumor growth and in response to some therapies, tumor cells experience acute or chronic deprivation of nutrients and oxygen and induce tumor vascularization. While this occurs predominately through sprouting angiogenesis, tumor cells have also been shown to directly contribute to vessel formation through vascular mimicry (VM) and/or endothelial transdifferentiation. The extrinsic and intrinsic mechanisms underlying tumor cell adoption of endothelial phenotypes, however, are not well understood. Here we show that serum withdrawal induces mesenchymal breast cancer cells to undergo VM and that knockdown of the epithelial-to-mesenchymal transition (EMT) regulator, Zinc finger E-box binding homeobox 1 (ZEB1), or overexpression of the ZEB1-repressed microRNAs (miRNAs), miR-200c, miR-183, miR-96 and miR-182 inhibits this process. We find that secreted proteins Fibronectin 1 (FN1) and serine protease inhibitor (serpin) family E member 2 (SERPINE2) are essential for VM in this system. These secreted factors are upregulated in mesenchymal cells in response to serum withdrawal, and overexpression of VM-inhibiting miRNAs abrogates this upregulation. Intriguingly, the receptors for these secreted proteins, low-density lipoprotein receptor-related protein 1 (LRP1) and Integrin beta 1 (ITGB1), are also targets of the VM-inhibiting miRNAs, suggesting that autocrine signaling stimulating VM is regulated by ZEB1-repressed miRNA clusters. Together, these data provide mechanistic insight into the regulation of VM and suggest that miRNAs repressed during EMT, in addition to suppressing migratory and stem-like properties of tumor cells, also inhibit endothelial phenotypes of breast cancer cells adopted in response to a nutrient-deficient microenvironment.


Subject(s)
Autocrine Communication , Biomarkers, Tumor/metabolism , Breast Neoplasms/blood supply , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , Neovascularization, Pathologic/pathology , Zinc Finger E-box-Binding Homeobox 1/metabolism , Animals , Apoptosis , Biomarkers, Tumor/genetics , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Movement , Cell Proliferation , Epithelial-Mesenchymal Transition , Female , Humans , Mice , Mice, Inbred BALB C , Mice, SCID , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Prognosis , Serpin E2/genetics , Serpin E2/metabolism , Tumor Cells, Cultured , Xenograft Model Antitumor Assays , Zinc Finger E-box-Binding Homeobox 1/genetics
2.
Meat Sci ; 94(4): 447-54, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23618740

ABSTRACT

Beef steaks (M. longissimus dorsi) were stored in modified atmosphere packs (MAP) (80% O2:20% CO2) with gas headspace to meat ratios of 2:1, 1:1 and 0.5:1 for 14 days at 4 °C. The pH, surface colour, texture and microbiology of beef steaks were unaffected (P>0.05) by varying the gas headspace to meat ratio. APLSR (ANOVA-partial least squares regression) and jack-knife uncertainty testing indicated that lipid oxidation (TBARS) was significantly positively correlated with days 10 (P<0.05) and 14 (P<0.001) of storage. Chemical and sensory detection of lipid oxidation in beef steaks were in agreement on day 14 of storage. The sensory quality and acceptability of beef steaks were similar in gas headspace to meat ratios of 2:1 or 1:1 and unacceptable in 0.5:1. Results indicate that pack size and gas volume can be reduced without negatively affecting fresh beef quality and shelf-life.


Subject(s)
Atmosphere , Food Packaging/methods , Food Preservation/methods , Lipid Peroxidation , Meat/analysis , Oxygen , Taste , Analysis of Variance , Animals , Cattle , Consumer Behavior , Diet , Humans , Least-Squares Analysis , Meat/standards
3.
Neuroscience ; 189: 215-22, 2011 Aug 25.
Article in English | MEDLINE | ID: mdl-21624435

ABSTRACT

The pathogenesis of neurodevelopmental disorders such as autism is believed to be influenced by interactions between genetic and environmental factors, and appropriate animal models are needed to assess the influence of such factors on relevant neurodevelopmental phenotypes. A set of inbred mouse strains (Atchley strains) including A12 (E+L0) and A22 (E-L0) were generated by age-specific restricted index selection from a baseline random-bred ICR mouse population obtained from Harlan Sprague-Dawley [Atchley et al. (1997) Genetics 146(2):629-640; Indianapolis, IN, USA). As compared with the A22 strain, A12 mice had significantly increased early (P0-P10) body weight gain with minimal changes in late (P28-P56) body weight gain. We found that these strains also differed in brain weight, brain volume, cell proliferation, and FGF-2 levels in certain brain regions. Specifically, brain weight and volume were significantly greater in A12 mice than that in A22 mice at P10 and P28. Quantitative analysis of bromodeoxyuridine (BrdU) labeling of proliferating cells showed that the number of BrdU-positive cells in the A12 strain were significantly greater in the frontal cortex and lesser in the dentate gyrus than that in the A22 strain at P28. Western blot revealed that fibroblast growth factors-2 (FGF-2), but not brain-derived neurotrophic factor (BDNF), expression was significantly increased in the frontal cortex of A12 strain at P28. Also, A12 mice exhibited decreased intra-strain social interaction and increased repetitive stereotyped behaviors at P28. Our study suggests that A12 mice may partially mimic the anatomic and behavioral traits of patients with neurodevelopmental disorders such as autism spectrum disorders, and therefore may yield insights into the developmental mechanisms involved in their pathogenesis.


Subject(s)
Autistic Disorder/pathology , Autistic Disorder/psychology , Brain/pathology , Age Factors , Animals , Brain/metabolism , Brain-Derived Neurotrophic Factor/metabolism , Cerebral Cortex/metabolism , Disease Models, Animal , Fibroblast Growth Factor 2/metabolism , Grooming , Hippocampus/metabolism , Interpersonal Relations , Mice , Mice, Inbred ICR , Organ Size , Species Specificity , Stereotyped Behavior
4.
Cancer Chemother Pharmacol ; 68(4): 863-70, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21286719

ABSTRACT

PURPOSE: Germline genetic variations may partly explain the clinical observation that normal tissue tolerance to radiochemotherapy varies by individual. Our objective was to evaluate the association between single-nucleotide polymorphisms (SNPs) in radiation/platinum pathways and serious treatment-related toxicity in subjects with esophageal adenocarcinoma who received cisplatin-based preoperative radiochemotherapy. METHODS: In a multicenter clinical trial (E1201), 81 eligible treatment-naïve subjects with resectable esophageal adenocarcinoma received cisplatin-based chemotherapy concurrent with radiotherapy, with planned subsequent surgical resection. Toxicity endpoints were defined as grade ≥3 radiation-related or myelosuppressive events probably or definitely related to therapy, occurring during or up to 6 weeks following the completion of radiochemotherapy. SNPs were analyzed in 60 subjects in pathways related to nucleotide/base excision- or double stranded break repair, or platinum influx, efflux, or detoxification. RESULTS: Grade ≥3 radiation-related toxicity (mostly dysphagia) and myelosuppression occurred in 18 and 33% of subjects, respectively. The variant alleles of the XRCC2 5' flanking SNP (detected in 28% of subjects) and of GST-Pi Ile-105-Val (detected in 65% of subjects) were each associated with higher odds of serious radiation-related toxicity compared to the major allele homozygote (47% vs. 9%, and 31% vs. 0%, respectively; P = 0.005). No SNP was associated with myelosuppression. CONCLUSIONS: This novel finding in a well-characterized cohort with robust endpoint data supports further investigation of XRCC2 and GST-Pi as potential predictors of radiation toxicity.


Subject(s)
Adenocarcinoma/therapy , Cisplatin/administration & dosage , DNA-Binding Proteins/genetics , Esophageal Neoplasms/therapy , Glutathione S-Transferase pi/genetics , Adenocarcinoma/genetics , Adult , Aged , Antineoplastic Agents/administration & dosage , Combined Modality Therapy , Esophageal Neoplasms/genetics , Female , Genetic Variation , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide , Radiation Injuries
5.
Plant Dis ; 95(2): 92-103, 2011 Feb.
Article in English | MEDLINE | ID: mdl-30743428

ABSTRACT

Common bunt, caused by the seedborne and soilborne pathogens Tilletia caries and T. laevis, has re-emerged as a major disease in organic wheat. In conventional agriculture, common bunt is routinely managed with the use of synthetic chemical seed treatments. For this reason, common bunt is a relatively unimportant disease in conventional agriculture. However, since synthetic chemical inputs are prohibited in organic agriculture, common bunt is a major threat once more in organic wheat and seed production. The challenge today is to manage the disease without the use of chemical seed treatments. This review reports on the management of common bunt under organic farming systems, mainly through host resistance and organic seed treatments. We report the history of screening wheat germplasm for bunt resistance, the search for new sources of resistance, and identification and mapping of bunt resistance genes. Since the pathogen has a gene-for-gene relationship with the host, this review also includes a summary of work on pathogen race identification and virulence patterns of field isolates. Also included are studies on the physiological and molecular basis of host resistance. Alternative seed treatments are discussed, including physical seed treatments, and microbial-based and plant-based treatments acceptable in organic systems. The article concludes with a brief discussion on the current gaps in research on the management of common bunt in organic wheat.

6.
Pathologica ; 103(5): 271-8, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22393682

ABSTRACT

Synovial sarcoma (SS) is a soft tissue neoplasm with clearly defined histologic, immunohistochemical and molecular features that usually arises in the extremities of young adults. The occurrence of these tumors in the kidney is extremely rare and have been prevalently described in case reports. The objectives of this work were to evaluate the frequency of primary renal synovial sarcomas and the pathologic progression in recognition of this possibly under-diagnosed entity. A comprehensive review of the literature has also been performed with a focus on survival. We report the clinico-pathological features of an intrarenal SS occurring in a 67-year-old man. The tumour, measuring 4 cm in its greatest diameter, completely replaced the cortex and the medulla of the inferior region of the left kidney compressing the iliopsoas muscle. Radiological imaging was consistent with a renal cell carcinoma. Histologically, the tumour was composed of atypical monotonous vimentin+, CD99+, bcl-2+ spindle cells exhibiting a haphazard fascicular growth pattern and a high mitotic rate (3 to 5 mitoses per HPF). The diagnosis was supported by reverse transcription-polymerase chain reaction which demonstrated SYT-SSX2 gene fusion. The patient was alive with local recurrence of disease 24 months after surgery. Synovial sarcomas occurring in the kidney, in analogy to other sites, tend to have an aggressive biologic behaviour. Despite being extremely uncommon, with only 44 cases reported to date, they should be included in the differential diagnosis of benign and malignant spindle cell tumours of the kidney. This study also emphasizes the importance of a correct pathologic diagnosis for prognostic and therapeutic implications.


Subject(s)
Kidney Neoplasms/pathology , Sarcoma, Synovial/pathology , Aged , Biomarkers, Tumor/metabolism , Carcinoma, Renal Cell/diagnosis , Carcinoma, Renal Cell/diagnostic imaging , Diagnosis, Differential , Humans , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , Male , Mitosis , Neoplasm Recurrence, Local , Oncogene Fusion , Oncogene Proteins, Fusion/genetics , Radiography , Sarcoma, Synovial/genetics , Sarcoma, Synovial/metabolism , Treatment Outcome
7.
Am J Transplant ; 7(12): 2663-74, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17983390

ABSTRACT

Complex interactions between positive and negative cosignaling receptors ultimately determine the fate of the immune response. The recently identified coinhibitory receptor, B and T lymphocyte attenuator (BTLA), contributes to regulation of autoimmune and potentially alloimmune responses. We investigated the role of BTLA in a fully major histocompatibility complex-mismatched mouse islet transplant model. We report that anti-BTLA mAb (6F7) alone does not accelerate graft rejection. Rather, while CTLA4Ig alone improved allograft survival, the addition of anti-BTLA mAb to CTLA4Ig led to indefinite (>100 days) allograft survival. Immediately after treatment with anti-BTLA mAb and CTLA4Ig, islet allografts showed intact islets and insulin production despite a host cellular response, with local accumulation of Foxp3+ cells. We clearly demonstrate that combined therapy with anti-BTLA mAb and CTLA4Ig mice induced donor-specific tolerance, since mice accepted a second donor-specific islet graft without further treatment and rejected third party grafts. CTLA4Ig and anti-BTLA mAb limited the initial in vivo proliferation of CFSE-labeled allogeneic lymphocytes, and anti-BTLA mAb enhanced the proportion of PD-1 expressing T cells while depleting pathogenic BTLA+ lymphocytes. We conclude that targeting the BTLA pathway in conjunction with CTLA4Ig costimulatory blockade may be a useful strategy for promoting immunological tolerance in murine islet allografts.


Subject(s)
Antibodies, Monoclonal/pharmacology , Immunoconjugates/pharmacology , Islets of Langerhans Transplantation/immunology , Receptors, Immunologic/immunology , Transplantation Tolerance/drug effects , Abatacept , Animals , Antibodies, Monoclonal/immunology , Antigens, Differentiation/metabolism , Blood Glucose/metabolism , CD4-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/pathology , Cell Proliferation/drug effects , Forkhead Transcription Factors/metabolism , Islets of Langerhans Transplantation/pathology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Knockout , Programmed Cell Death 1 Receptor , Receptors, Immunologic/genetics , Receptors, Immunologic/metabolism , T-Lymphocytes, Regulatory/metabolism , T-Lymphocytes, Regulatory/pathology , Transplantation Tolerance/immunology , Transplantation, Homologous , Up-Regulation/drug effects
9.
Int J Obes (Lond) ; 30(8): 1211-6, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16446745

ABSTRACT

OBJECTIVE: To determine if hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise differentially influence subcutaneous abdominal and gluteal adipocyte size in obese individuals. DESIGN: Longitudinal intervention study of hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise (calorie deficit = 2800 kcal/week, 20 weeks). SUBJECTS: Forty-five obese, middle-aged women (BMI = 33.0+/-0.6 kg/m2, age = 58+/-1 years). MEASUREMENTS: Body composition testing and adipose tissue biopsies were conducted before and after the interventions. Subcutaneous abdominal and gluteal adipocyte size was determined. RESULTS: All three interventions reduced body weight, fat mass, percent fat, and waist and hip girths to a similar degree. Diet only did not change subcutaneous abdominal adipocyte size, whereas both diet plus exercise groups significantly reduced abdominal adipocyte size. Changes in abdominal adipocyte size in the diet plus exercise groups were significantly different from that of the diet group. Gluteal adipocyte size decreased similarly in all three groups. CONCLUSION: Addition of exercise training to dietary weight loss preferentially reduces subcutaneous abdominal adipocyte size in obese women. This may be of importance for the treatment of health complications associated with subcutaneous abdominal adiposity.


Subject(s)
Adipocytes/cytology , Diet, Reducing , Exercise/physiology , Obesity/therapy , Weight Loss/physiology , Body Composition/physiology , Cell Size , Combined Modality Therapy , Female , Humans , Middle Aged , Oxygen Consumption , Subcutaneous Fat, Abdominal/cytology
12.
Am J Hosp Palliat Care ; 20(3): 211-9, 2003.
Article in English | MEDLINE | ID: mdl-12785043

ABSTRACT

Large numbers of persons in most types of healthcare settings have palliative care needs that have considerable impact on their quality of life. Therefore, InterRAI, a multinational consortium of researchers, clinicians, and regulators that uses assessment systems to improve the care of elderly and disabled persons, designed a standardized assessment tool, the Resident Assessment Instrument for Palliative Care (RAI-PC). The RAI-PC can be used for both the design of individual care plans and for case mix and outcomes research. Some elements of this instrument are taken from the resident assessment instrument (RAI) mandated for use in all nursing homes in the United States and widely used throughout the world. The RAI-PC can be used alone or in counjunction with the other assessment tools designed by the InterRAI collaboration: the RAI for homecare (RAI-HC), for acute care (RAI-AC), and for mental health care (RAI-MH). The objective of this study was to field test and carry out reliability studies on the RAI-PC. After appropriate approvals were obtained, the RAI-PC instrument was field tested on 151 persons in three countries in more than five types of settings. Data obtained from 144 of these individuals were analyzed for reliability. The reliability of the instrument was very good, with about 50 percent of the questions having kappa values of 0.8 or higher, and the average kappa value for each of the eight domains ranging from 0.76 to 0.95. The 54 men and 95 women had a mean age of 79 years. Thirty-four percent of individuals suffered pain daily. Eighty percent tired easily; 52 percent were breathless on exertion; and 19 to 53 percent had one or more other symptoms, including change in sleep pattern, dry mouth, nausea and vomiting, anorexia, breathlessness at rest, constipation, and diarrhea. The number of symptoms an individual reported increased as the estimated time until death declined. The "clinician friendly" RAI-PC can be used in multiple sites of care to facilitate both care planning and case mix and outcomes research.


Subject(s)
Geriatric Assessment , Palliative Care , Patient Care Planning , Adult , Aged , Czech Republic , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sweden , United States
14.
Br J Biomed Sci ; 60(4): 204-9, 2003.
Article in English | MEDLINE | ID: mdl-14725336

ABSTRACT

A total of 56 Neisseria meningitidis strains are analysed using multilocus sequence typing (MLST). Twenty-nine distinct sequence types (STs) were identified, eight of which were new. Four known hypervirulent clones--ST-11 (electrophoretic type [ET]-37) complex, ST-44 complex (lineage 3), ST-32 (ET-5) complex and ST-8 complex (cluster A4)--were identified by MLST in 35 disease-associated and four carrier strains. Two other clones (ST-22 complex and ST-269 complex) were identified in nine disease-associated and one carrier strain. The remaining strains were heterogeneous. Additional sequencing within the FumC gene further distinguished the ET-15 clone within the ST-11 (ET-37) clonal complex. This resolution of isolates into genetic clones by MLST enhances the more traditional techniques of serotyping and serosubtyping. The data obtained established that hyperendemic meningococcal disease in Ireland could be attributed to strains belonging to four major hypervirulent clones, all of which account for elevated levels of disease worldwide. The extra information provided by MLST will be used to study the population structure and epidemiology of N. meningitidis and will allow a comparison of Irish strains with those circulating globally.


Subject(s)
Meningococcal Infections/microbiology , Neisseria meningitidis/classification , Bacterial Typing Techniques/methods , DNA, Bacterial/genetics , Humans , Molecular Sequence Data , Sequence Analysis, DNA/methods , Serotyping
15.
J Neurosci Res ; 67(3): 372-8, 2002 Feb 01.
Article in English | MEDLINE | ID: mdl-11813242

ABSTRACT

Striatal neurons in symptomatic Huntington's disease (HD) transgenic mice are resistant to a variety of toxic insults, including quinolinic acid (QA), kainic acid and 3-nitropropionic acid. The basis for this resistance is currently unknown. To investigate the possibility that the immediate-early gene (IEG) response is defective in symptomatic HD mice leading to a lack of response to these compounds, we examined the expression of c-Fos and Krox 24 after administration of the indirect dopamine agonist methamphetamine, the dopamine D(2) receptor antagonist haloperidol and the neurotoxin QA in 5- and 10-week-old R6/2 transgenic HD and wild-type mice. Unlike wild-type and pre-symptomatic R6/2 transgenic HD mice, 10-week-old symptomatic HD mice were resistant to methamphetamine-induced gliosis and QA lesion. There was, however, no difference in the number or distribution of c-Fos-immunoreactive nuclei 2 hr after single injections of methamphetamine or haloperidol among 5- and 10-week-old wild-type mice and 5- and 10-week-old R6/2 HD mice. Similarly, despite their resistance to QA-induced lesioning and lower basal levels of krox-24 mRNA, the symptomatic R6/2 mice had equivalent increases in the amount of c-fos and krox-24 mRNA compared to wild-type and pre-symptomatic R6/2 HD mice as determined by in situ hybridization and densitometry 2 hr after QA administration. These data demonstrate that the c-Fos and Krox 24 IEG response to dopamine agonists, dopamine antagonists and neurotoxic insult is functional in symptomatic R6/2 HD mice. Resistance to toxic insult in R6/2 mice may be conferred by interactions of mutant huntingtin with proteins or transcriptional processes further along the toxic cascade.


Subject(s)
Genes, Immediate-Early/drug effects , Haloperidol/pharmacology , Huntington Disease/metabolism , Immediate-Early Proteins , Methamphetamine/pharmacology , Nerve Tissue Proteins , Quinolinic Acid/pharmacology , Animals , Anti-Dyskinesia Agents/pharmacology , Central Nervous System Stimulants/pharmacology , Corpus Callosum/drug effects , Corpus Callosum/metabolism , Corpus Callosum/pathology , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Corpus Striatum/pathology , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Disease Models, Animal , Dopamine Antagonists/pharmacology , Dopamine and cAMP-Regulated Phosphoprotein 32 , Early Growth Response Protein 1 , Gene Expression/drug effects , Glial Fibrillary Acidic Protein/metabolism , Huntington Disease/genetics , Huntington Disease/pathology , Mice , Mice, Transgenic , Phosphoproteins/metabolism , Proto-Oncogene Proteins c-fos/genetics , Proto-Oncogene Proteins c-fos/metabolism , RNA, Messenger/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
16.
Br J Cancer ; 85(10): 1564-71, 2001 Nov 16.
Article in English | MEDLINE | ID: mdl-11720446

ABSTRACT

We have previously reported a strong correlation between poor prognosis in childhood neuroblastoma (NB) patients and high-level expression of the transmembrane efflux pump, Multidrug Resistance-associated Protein (MRP1), in NB tumour tissue. In this study, we inhibited the endogenous expression of MRP1 in 2 different NB tumour cell lines by stably transfecting an MRP1 antisense expression vector (MRP-AS). Compared with control cells, MRP-AS transfectant cells demonstrated a higher proportion of dead and morphologically apoptotic cells, spontaneous neuritogenesis, and, increased synaptophysin and neurofilament expression. Bcl-2 protein expression was markedly reduced in MRP-AS cells compared to controls. Conversely, we found that the same NB tumour cell line overexpressing the full-length MRP1 cDNA in sense orientation (MRP-S) demonstrated resistance to the neuritogenic effect of the differentiating agent, all-trans-retinoic acid. Taken together, the results suggest that the level of MRP1 expression in NB tumour cells may influence the capacity of NB cells for spontaneous regression in vivo through cell differentiation and death.


Subject(s)
Apoptosis , Multidrug Resistance-Associated Proteins/metabolism , Multidrug Resistance-Associated Proteins/physiology , Neuroblastoma/pathology , Cell Differentiation , Cell Division , Clone Cells , Dose-Response Relationship, Drug , Down-Regulation , Gene Expression , Humans , In Situ Nick-End Labeling , Microscopy, Fluorescence , Multidrug Resistance-Associated Proteins/genetics , Neuroblastoma/metabolism , Oligonucleotides, Antisense/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Transfection , Tretinoin/antagonists & inhibitors , Tumor Cells, Cultured
17.
J Exp Med ; 194(10): 1461-71, 2001 Nov 19.
Article in English | MEDLINE | ID: mdl-11714753

ABSTRACT

The development of naive CD4+ T cells into a T helper (Th) 2 subset capable of producing interleukin (IL)-4, IL-5, and IL-13 involves a signal transducer and activator of transcription (Stat)6-dependent induction of GATA-3 expression, followed by Stat6-independent GATA-3 autoactivation. The friend of GATA (FOG)-1 protein regulates GATA transcription factor activity in several stages of hematopoietic development including erythrocyte and megakaryocyte differentiation, but whether FOG-1 regulates GATA-3 in T cells is uncertain. We show that FOG-1 can repress GATA-3-dependent activation of the IL-5 promoter in T cells. Also, FOG-1 overexpression during primary activation of naive T cells inhibited Th2 development in CD4+ T cells. FOG-1 fully repressed GATA-3-dependent Th2 development and GATA-3 autoactivation, but not Stat6-dependent induction of GATA-3. FOG-1 overexpression repressed development of Th2 cells from naive T cells, but did not reverse the phenotype of fully committed Th2 cells. Thus, FOG-1 may be one factor capable of regulating the Th2 development.


Subject(s)
CD4-Positive T-Lymphocytes/physiology , Carrier Proteins/physiology , DNA-Binding Proteins/physiology , Nuclear Proteins/physiology , Trans-Activators/physiology , Animals , GATA3 Transcription Factor , Interleukin-4/pharmacology , Mice , Mice, Transgenic , STAT6 Transcription Factor , Th2 Cells/physiology , Transcription Factors , Transcription, Genetic
19.
J Immunol ; 167(2): 855-65, 2001 Jul 15.
Article in English | MEDLINE | ID: mdl-11441092

ABSTRACT

Analysis of the IFN-gamma promoter has primarily been conducted by transient expression of reporter constructs in transformed cells. However, the activity of cis elements may differ when expressed transiently compared with their activity within native chromatin. Furthermore, the transcription factors and signaling mechanisms in transformed cells may differ from those in normal T cells. To analyze IFN-gamma promoter regulation in normal T cells, we developed a novel retroviral bottom-strand reporter system to allow the chromatin integration of promoter regions in primary developing T cells. As controls, both the IL-2 and IL-4 promoters were inducible in this system, with the IL-4 reporter having Th2-specific activity. Strikingly, the IFN-gamma promoter exhibited constitutive activity in both Th1 and Th2 subsets, in contrast to the behavior of the endogenous IFN-gamma gene, which is inducible only in Th1 cells. In mapping this activity, we found that the AP-1/GM-CSF site in the distal promoter element is the most critical element for the constitutive activity. Transgenic reporter lines for the IFN-gamma promoter confirmed the constitutive behavior of the isolated IFN-gamma promoter. This constitutive activity was resistant to inhibition by cyclosporin A and was independent of Stat4 and p38 mitogen-activated protein kinase. These results suggest that IFN-gamma promoter regulation may require cis elements residing either downstream or >3.4 kb upstream of the transcriptional start site, involving repression of constitutive activity.


Subject(s)
Genes, Reporter/immunology , Interferon-gamma/genetics , Lymphocyte Activation/genetics , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Animals , Cell Line , Cell Line, Transformed , Cyclosporine/pharmacology , DNA-Binding Proteins/physiology , Female , Gene Expression Regulation/drug effects , Gene Expression Regulation/immunology , Granulocyte-Macrophage Colony-Stimulating Factor/genetics , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Interferon-gamma/biosynthesis , Interferon-gamma/metabolism , Mice , Mice, Inbred BALB C , Mice, Transgenic , Mitogen-Activated Protein Kinases/physiology , Mutagenesis, Insertional , Promoter Regions, Genetic/drug effects , Promoter Regions, Genetic/immunology , STAT4 Transcription Factor , T-Lymphocytes/drug effects , Trans-Activators/physiology , Transcription Factor AP-1/genetics , Transcription Factor AP-1/metabolism , Tumor Cells, Cultured
20.
Mol Cell Biol ; 21(9): 3206-19, 2001 May.
Article in English | MEDLINE | ID: mdl-11287624

ABSTRACT

Emk is a serine/threonine protein kinase implicated in regulating polarity, cell cycle progression, and microtubule dynamics. To delineate the role of Emk in development and adult tissues, mice lacking Emk were generated by targeted gene disruption. Emk(-/-) mice displayed growth retardation and immune cell dysfunction. Although B- and T-cell development were normal, CD4(+)T cells lacking Emk exhibited a marked upregulation of the memory marker CD44/pgp-1 and produced more gamma interferon and interleukin-4 on stimulation through the T-cell receptor in vitro. In addition, B-cell responses to T-cell-dependent and -independent antigen challenge were altered in vivo. As Emk(-/-) animals aged, they developed splenomegaly, lymphadenopathy, membranoproliferative glomerulonephritis, and lymphocytic infiltrates in the lungs, parotid glands and kidneys. Taken together, these results demonstrate that the Emk protein kinase is essential for maintaining immune system homeostasis and that loss of Emk may contribute to autoimmune disease in mammals.


Subject(s)
Autoimmune Diseases/enzymology , B-Lymphocytes/immunology , Caenorhabditis elegans Proteins , Cell Cycle Proteins , Protein Serine-Threonine Kinases/immunology , T-Lymphocytes/immunology , Animals , Autoimmune Diseases/immunology , B-Lymphocytes/cytology , B-Lymphocytes/physiology , Cell Differentiation , Colon/abnormalities , Female , Gene Expression , Gene Targeting , Glomerulonephritis, Membranoproliferative/enzymology , Hemoglobinuria/enzymology , Humans , Immune System/immunology , Lymphoid Tissue , Mice , Mice, Inbred C57BL , Mice, Knockout , Prolapse , Protein Serine-Threonine Kinases/genetics , Proteinuria/enzymology , T-Lymphocytes/cytology , T-Lymphocytes/physiology
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