[Distribution diversity of integrins and calcium channels on major human and mouse host cells of Leptospira species].

PubMed

Li, Cheng-xue; Zhao, Xin; Qian, Jing; Yan, Jie

2012-07-01

To determine the distribution of integrins and calcium channels on major human and mouse host cells of Leptospira species. The expression of β1, β2 and β3 integrins was detected with immunofluorescence assay on the surface of human monocyte line THP-1, mouse mononuclear-macrophage-like cell line J774A.1, human vascular endothelial cell line HUVEC, mouse vascular endothelial cell EOMA, human hepatocyte line L-02, mouse hepatocyte line Hepa1-6, human renal tubular epithelial cell line HEK-293, mouse glomerular membrane epithelial cell line SV40-MES13, mouse collagen blast line NIH/3T3, human and mouse platelets. The distribution of voltage gate control calcium channels Cav3.1, Cav3.2, Cav3.3 and Cav2.3, and receptor gate calcium channels P(2)X(1), P(2)2X(2), P(2)X(3), P(2)X(4), P(2)X(5), P(2)X(6) and P(2)X(7) were determined with Western blot assay. β1 integrin proteins were positively expressed on the membrane surface of J774A.1, THP-1, HUVEC, EOMA, L-02, Hepa1-6 and HEK-239 cells as well as human and mouse platelets. β2 integrin proteins were expressed on the membrane surface of J774A.1, THP-1, HUVEC, EOMA, and NIH/3T3 cells. β3 integrin proteins were expressed on the membrane surface of J774A.1, THP-1, HUVEC, EOMA, Hepa1-6, HEK-239 and NIH/3T3 cells as well as human and mouse platelets. P(2)X(1) receptor gate calcium channel was expressed on the membrane surface of human and mouse platelets, while P(2)X(5) receptor gate calcium channel was expressed on the membrane surface of J774A.1, THP-1, L-02, Hepa1-6, HEK-239 and HUVEC cells. However, the other calcium channels were not detected on the tested cell lines or platelets. There is a large distribution diversity of integrins and calcium channel proteins on the major human and mouse host cells of Leptospira species, which may be associated with the differences of leptospira-induced injury in different host cells.

Differences between Mycobacterium-Host Cell Relationships in Latent Tuberculous Infection of Mice Ex Vivo and Mycobacterial Infection of Mouse Cells In Vitro

PubMed Central

Ufimtseva, Elena

2016-01-01

The search for factors that account for the reproduction and survival of mycobacteria, including vaccine strains, in host cells is the priority for studies on tuberculosis. A comparison of BCG-mycobacterial loads in granuloma cells obtained from bone marrow and spleens of mice with latent tuberculous infection and cells from mouse bone marrow and peritoneal macrophage cultures infected with the BCG vaccine in vitro has demonstrated that granuloma macrophages each normally contained a single BCG-Mycobacterium, while those acutely infected in vitro had increased mycobacterial loads and death rates. Mouse granuloma cells were observed to produce the IFNγ, IL-1α, GM-CSF, CD1d, CD25, CD31, СD35, and S100 proteins. None of these activation markers were found in mouse cell cultures infected in vitro or in intact macrophages. Lack of colocalization of lipoarabinomannan-labeled BCG-mycobacteria with the lysosomotropic LysoTracker dye in activated granuloma macrophages suggests that these macrophages were unable to destroy BCG-mycobacteria. However, activated mouse granuloma macrophages could control mycobacterial reproduction in cells both in vivo and in ex vivo culture. By contrast, a considerable increase in the number of BCG-mycobacteria was observed in mouse bone marrow and peritoneal macrophages after BCG infection in vitro, when no expression of the activation-related molecules was detected in these cells. PMID:27066505

The PPARδ ligand GW501516 reduces growth but not apoptosis in mouse inner medullary collecting duct cells.

PubMed

Clark, Jordan; Nasrallah, Rania; Hébert, Richard L

2009-01-01

The collecting duct (CD) expresses considerable amounts of PPARδ. While its role is unknown in the CD, in other renal cells it has been shown to regulate both growth and apoptosis. We thus hypothesized that PPARδ reduces apoptotic responses and stimulates cell growth in the mouse CD, and examined the effect of GW501516, a synthetic PPARδ ligand, on these responses in mouse IMCD-K2 cells. High doses of GW501516 decreased both DNA and protein synthesis in these cells by 80%, but had no overall effect on cell viability. Although anisomycin treatment resulted in an increase of caspase-3 levels of about 2.59-fold of control, GW501516 did not affect anisomycin-induced changes in active caspase-3 levels. These results show that a PPARδ ligand inhibits growth but does not affect anisomycin-apoptosis in a mouse IMCD cell line. This could have therapeutic implications for renal diseases associated with increased CD growth responses.

A Direct Synergistic Effect of Immunotherapy and Chemotherapy as a New Paradigm in Treatment of Breast Cancer

DTIC Science & Technology

2010-04-01

mouse macrophage nucleofector kit (Program-Y-01) was used. For EL4 cells mouse cell transfection kit (Program-C-09) was used. As controls...direct synergy between immunotherapy and chemotherapy in vitro. We found that pre-treatment of tumor target cells with doxorubicin or paclitaxel...significantly increased cytotoxic effect of T-lymphocytes. Importantly, that effect was antigen-specific, since it was observed only in tumor cells loaded

Development of a novel mouse glioma model using lentiviral vectors

PubMed Central

Marumoto, Tomotoshi; Tashiro, Ayumu; Friedmann-Morvinski, Dinorah; Scadeng, Miriam; Soda, Yasushi; Gage, Fred H; Verma, Inder M

2009-01-01

We report the development of a new method to induce glioblastoma multiforme in adult immunocompetent mice by injecting Cre-loxP–controlled lentiviral vectors expressing oncogenes. Cell type- or region-specific expression of activated forms of the oncoproteins Harvey-Ras and AKT in fewer than 60 glial fibrillary acidic protein–positive cells in the hippocampus, subventricular zone or cortex of mice heterozygous for the gene encoding the tumor suppressor Tp53 were tested. Mice developed glioblastoma multiforme when transduced either in the subventricular zone or the hippocampus. However, tumors were rarely detected when the mice were transduced in the cortex. Transplantation of brain tumor cells into naive recipient mouse brain resulted in the formation of glioblastoma multiforme–like tumors, which contained CD133+ cells, formed tumorspheres and could differentiate into neurons and astrocytes. We suggest that the use of Cre-loxP–controlled lentiviral vectors is a novel way to generate a mouse glioblastoma multiforme model in a region- and cell type-specific manner in adult mice. PMID:19122659

AMPK/p53 Axis Is Essential for α-Lipoic Acid-Regulated Metastasis in Human and Mouse Colon Cancer Cells.

PubMed

Park, Sunmi; Choi, Seung Kug; Choi, Yura; Moon, Hyun-Seuk

2015-10-01

α-Lipoic acid (ALA) has an anticancer property of lung, cervix, and prostate cancer cells. However, direct evidence that ALA contributes to the development of colon cancer has not been fully elucidated. In addition, no previous studies have evaluated whether ALA may regulate malignant potential, such as adhesion, invasion, and colony formation of colon cancer cells. To address the aforementioned questions, we conducted in vitro ALA signaling studies using human (HT29) and mouse (MCA38) colon cancer cell lines. We observed that cell proliferation is reduced by ALA administration in a dose-dependent manner in human and mouse colon cancer cell lines. Specifically, 0.5 to 1 mM concentration of ALA significantly decreased cell proliferation when compared with control. Similarly, we found that ALA downregulates adhesion, invasion, and colony formation. Finally, we observed that ALA activates p53 and AMPK signaling pathways in human and mouse colon cancer cells. We found for the first time that ALA suppresses cell proliferation and malignant potential via p53 and AMPK signaling pathways in human and mouse colon cancer cells. These new and early mechanistic studies provide a causal role of ALA in colon cancer, suggesting that ALA might be a useful agent in the management or chemoprevention of colon cancer.

A PML/Slit Axis Controls Physiological Cell Migration and Cancer Invasion in the CNS.

PubMed

Amodeo, Valeria; A, Deli; Betts, Joanne; Bartesaghi, Stefano; Zhang, Ying; Richard-Londt, Angela; Ellis, Matthew; Roshani, Rozita; Vouri, Mikaella; Galavotti, Sara; Oberndorfer, Sarah; Leite, Ana Paula; Mackay, Alan; Lampada, Aikaterini; Stratford, Eva Wessel; Li, Ningning; Dinsdale, David; Grimwade, David; Jones, Chris; Nicotera, Pierluigi; Michod, David; Brandner, Sebastian; Salomoni, Paolo

2017-07-11

Cell migration through the brain parenchyma underpins neurogenesis and glioblastoma (GBM) development. Since GBM cells and neuroblasts use the same migratory routes, mechanisms underlying migration during neurogenesis and brain cancer pathogenesis may be similar. Here, we identify a common pathway controlling cell migration in normal and neoplastic cells in the CNS. The nuclear scaffold protein promyelocytic leukemia (PML), a regulator of forebrain development, promotes neural progenitor/stem cell (NPC) and neuroblast migration in the adult mouse brain. The PML pro-migratory role is active also in transformed mouse NPCs and in human primary GBM cells. In both normal and neoplastic settings, PML controls cell migration via Polycomb repressive complex 2 (PRC2)-mediated repression of Slits, key regulators of axon guidance. Finally, a PML/SLIT1 axis regulates sensitivity to the PML-targeting drug arsenic trioxide in primary GBM cells. Taken together, these findings uncover a drug-targetable molecular axis controlling cell migration in both normal and neoplastic cells. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of several salt marsh plants on mouse spleen and thymus cell proliferation using mtt assay

NASA Astrophysics Data System (ADS)

Seo, Youngwan; Lee, Hee-Jung; Kim, You Ah; Youn, Hyun Joo; Lee, Burm-Jong

2005-12-01

In the present study, we have tested the effects of 21 salt marsh plants on cell proliferation of mouse immune cells (spleen and thymus) using MTT assay in culture. The methanolic extracts of six salt marsh plants ( Rosa rugosa, Ixeris tamagawaensis, Artemisia capillaris, Tetragonia tetragonoides, Erigeron annus, and Glehnia littoralis) showed very powerful suppressive effects of mouse immune cell death and significant activities of cell proliferation in vitro. Especially, the methanolic extract of Rosa rugosa was found to have fifteen times compared to the control treatment, demonstrating that Rosa rugosa may have a potent stimulation effect on immune cell proliferation. These results suggest that several salt marsh plants including Rosa rugosa could be useful for further study as an immunomodulating agent.

TGF-β induces surface LAP expression on murine CD4 T cells independent of Foxp3 induction.

PubMed

Oida, Takatoku; Weiner, Howard L

2010-11-24

It has been reported that human FOXP3(+) CD4 Tregs express GARP-anchored surface latency-associated peptide (LAP) after activation, based on the use of an anti-human LAP mAb. Murine CD4 Foxp3(+) Tregs have also been reported to express surface LAP, but these studies have been hampered by the lack of suitable anti-mouse LAP mAbs. We generated anti-mouse LAP mAbs by immunizing TGF-β(-/-) animals with a mouse Tgfb1-transduced P3U1 cell line. Using these antibodies, we demonstrated that murine Foxp3(+) CD4 Tregs express LAP on their surface. In addition, retroviral transduction of Foxp3 into mouse CD4(+)CD25(-) T cells induced surface LAP expression. We then examined surface LAP expression after treating CD4(+)CD25(-) T cells with TGF-β and found that TGF-β induced surface LAP not only on T cells that became Foxp3(+) but also on T cells that remained Foxp3(-) after TGF-β treatment. GARP expression correlated with the surface LAP expression, suggesting that surface LAP is GARP-anchored also in murine T cells. Unlike human CD4 T cells, surface LAP expression on mouse CD4 T cells is controlled by Foxp3 and TGF-β. Our newly described anti-mouse LAP mAbs will provide a useful tool for the investigation and functional analysis of T cells that express LAP on their surface.

Unexpected effects of different genetic backgrounds on identification of genomic rearrangements via whole-genome next generation sequencing.

PubMed

Chen, Zhangguo; Gowan, Katherine; Leach, Sonia M; Viboolsittiseri, Sawanee S; Mishra, Ameet K; Kadoishi, Tanya; Diener, Katrina; Gao, Bifeng; Jones, Kenneth; Wang, Jing H

2016-10-21

Whole genome next generation sequencing (NGS) is increasingly employed to detect genomic rearrangements in cancer genomes, especially in lymphoid malignancies. We recently established a unique mouse model by specifically deleting a key non-homologous end-joining DNA repair gene, Xrcc4, and a cell cycle checkpoint gene, Trp53, in germinal center B cells. This mouse model spontaneously develops mature B cell lymphomas (termed G1XP lymphomas). Here, we attempt to employ whole genome NGS to identify novel structural rearrangements, in particular inter-chromosomal translocations (CTXs), in these G1XP lymphomas. We sequenced six lymphoma samples, aligned our NGS data with mouse reference genome (in C57BL/6J (B6) background) and identified CTXs using CREST algorithm. Surprisingly, we detected widespread CTXs in both lymphomas and wildtype control samples, majority of which were false positive and attributable to different genetic backgrounds. In addition, we validated our NGS pipeline by sequencing multiple control samples from distinct tissues of different genetic backgrounds of mouse (B6 vs non-B6). Lastly, our studies showed that widespread false positive CTXs can be generated by simply aligning sequences from different genetic backgrounds of mouse. We conclude that mapping and alignment with reference genome might not be a preferred method for analyzing whole-genome NGS data obtained from a genetic background different from reference genome. Given the complex genetic background of different mouse strains or the heterogeneity of cancer genomes in human patients, in order to minimize such systematic artifacts and uncover novel CTXs, a preferred method might be de novo assembly of personalized normal control genome and cancer cell genome, instead of mapping and aligning NGS data to mouse or human reference genome. Thus, our studies have critical impact on the manner of data analysis for cancer genomics.

Tenascin-C Deficiency in Apo E−/− Mouse Increases Eotaxin Levels: Implications for Atherosclerosis

PubMed Central

Wang, Lai; Shah, Prediman K.; Wang, Wei; Song, Lei; Yang, Mingjie; Sharifi, Behrooz G.

2013-01-01

Aim To investigate the potential role of inflammatory cytokines in apo E−/− mouse in response to deletion of Tenascin-C (TNC) gene. Methods and results We used antibody array and ELISA to compare the profile of circulating inflammatory cytokines in apo E−/− mice and apo E−/− TNC−/− double knockout mice. In addition, tissue culture studies were performed to investigate the activity of cells from each mouse genotype in vitro. Cytokine array analysis and subsequent ELISA showed that circulating eotaxin levels were selectively and markedly increased in response to TNC gene deletion in apo E−/− mice. In addition, considerable variation was noted in the circulating level of eotaxin among the control apo E−/− mouse group. Inbreeding of apo E−/− mice with high or low levels of plasma eotaxin showed that the level of eotaxin per se determines the extent of atherosclerosis in this mouse genotype. While endothelial cells from apo E−/− mice had low level of eotaxin expression, cells derived from apo E−/−TNC−/− mice expressed a high level of eotaxin. Transient transfection of eotaxin promoter-reporter constructs revealed that eotaxin expression is regulated at the transcriptional level by TNC. Histochemical analysis of aortic sections revealed the massive accumulation of mast cells in the adventitia of double KO mice lesions whereas no such accumulation was detected in the control group. Plasma from the apo E−/−TNC−/− mice markedly stimulated mast cell migration whereas plasma from the apo E−/− mice had no such effect. Conclusion These observations support the emerging hypothesis that TNC expression controls eotaxin level in apo E−/− mice and that this chemokine plays a key role in the development of atherosclerosis. PMID:23433402

[Effects of simulated hypoxia on dielectric properties of mouse erythrocytes].

PubMed

Ma, Qing; Tang, Zhi-Yuan; Wang, Qin-Wen; Zhao, Xin

2008-02-01

To explore the influence of simulated altitude hypoxia on dielectric properties of mouse erythrocytes. Experimental animals were divided into the plain control group(control) and simulated altitude hypoxia group (altitude). The AC impedance of mouse erythrocytes was measured with the Agilent 4294A impedance analyzer, the influence of simulated altitude hypoxia on dielectric properties of mouse erythrocytes was observed by cell dielectric spectroscopy, Cole-Cole plots, loss factor spectrum, loss tangent spectrum, and curve fitting analysis of Cole-Cole equation. After mice were exposed to hypoxia at simulated 5000 m altitude for 4 weeks, permittivity at low frequency (epsilonl) and dielectric increment (deltaepsilon) increased 57% and 59% than that of control group respectively, conductivity at low frequency (kappal) and conductivity at high frequency (kappah) reduced 49% and 11% than that of control group respectively. The simulated altitude hypoxia could arise to increase dielectric capability and depress conductive performance on mouse erythrocytes.

Automatic detection and quantitative analysis of cells in the mouse primary motor cortex

NASA Astrophysics Data System (ADS)

Meng, Yunlong; He, Yong; Wu, Jingpeng; Chen, Shangbin; Li, Anan; Gong, Hui

2014-09-01

Neuronal cells play very important role on metabolism regulation and mechanism control, so cell number is a fundamental determinant of brain function. Combined suitable cell-labeling approaches with recently proposed three-dimensional optical imaging techniques, whole mouse brain coronal sections can be acquired with 1-μm voxel resolution. We have developed a completely automatic pipeline to perform cell centroids detection, and provided three-dimensional quantitative information of cells in the primary motor cortex of C57BL/6 mouse. It involves four principal steps: i) preprocessing; ii) image binarization; iii) cell centroids extraction and contour segmentation; iv) laminar density estimation. Investigations on the presented method reveal promising detection accuracy in terms of recall and precision, with average recall rate 92.1% and average precision rate 86.2%. We also analyze laminar density distribution of cells from pial surface to corpus callosum from the output vectorizations of detected cell centroids in mouse primary motor cortex, and find significant cellular density distribution variations in different layers. This automatic cell centroids detection approach will be beneficial for fast cell-counting and accurate density estimation, as time-consuming and error-prone manual identification is avoided.

Feasibility study of a biocompatible pneumatic dispensing system using mouse 3T3-J2 fibroblasts

NASA Astrophysics Data System (ADS)

Lee, Sangmin; Kim, Hojin; Kim, Joonwon

2017-12-01

This paper presents results for dispensing living cells using a pneumatic dispensing system to verify the feasibility of using this system to fabricate biomaterials. Living cells (i.e., mouse 3T3-J2 fibroblast) were dispensed with different dispensing pressures in order to evaluate the effect of dispensing process on cell viability and proliferation. Based on the results of a live-dead assay, more than 80% of cell viability has been confirmed which was reasonably similar to that in the control group. Furthermore, measurement of cell metabolic activity after dispensing confirmed that the dispensed cell proliferated at a rate comparable to that of the control group. These results demonstrate that the pneumatic dispensing system is a promising tool for fabrication of biomaterials.

The diabetes type 1 locus Idd6 modulates activity of CD4+CD25+ regulatory T-cells.

PubMed

Rogner, Ute Christine; Lepault, Françoise; Gagnerault, Marie-Claude; Vallois, David; Morin, Joëlle; Avner, Philip; Boitard, Christian

2006-01-01

The genetic locus Idd6 confers susceptibility to the spontaneous development of type 1 diabetes in the NOD mouse. Our studies on disease resistance of the congenic mouse strain NOD.C3H 6.VIII showed that Idd6 influences T-cell activities in the peripheral immune system and suggest that a major mechanism by which the Idd6 locus modifies diabetes development is via modulation of regulatory T-cell activities. Our transfer experiments using total splenocytes and purified T-cells demonstrated that the locus specifically controls the efficiency of disease protection mediated by the regulatory CD4(+)CD25(+) T-cell subset. Our data also implicate the Idd6 locus in controlling the balance between infiltrating lymphocytes and antigen-presenting cells within the pancreatic islet.

Studies on Typhus and Spotted Fever.

DTIC Science & Technology

1980-02-01

prowazekii-infected human somatic (fibroblast, endothelia)), but not chick, mouse or monkey , cells in culture: (a) intracellular antirickettsial action...that of the controls. No such effect on growth was apparent in CE cells, Nu E % o0 M Ŕ ZOO - .0 E 00 (1 CI - 4D W = .) C ~ o r- -!NBI Go !N 21501,,o o...human origin transformed or malignant cells, monkey primary or diploid and primary mouse embryo fibroblasts will permit expression of these effects to

Mouse model of plasma cell mastitis.

PubMed

Yu, Jian-jun; Bao, Shan-lin; Yu, Sheng-lin; Zhang, Da-Qing; Loo, Wings T Y; Chow, Louis W C; Su, Li; Cui, Zhen; Chen, Kai; Ma, Li-Qiong; Zhang, Ning; Yu, Hui; Yang, Yun-Zhen; Dong, Yu; Yip, Adrian Y S; Ng, Elizabeth L Y

2012-09-19

Plasma cell mastitis is distinct from the common form of mastitis and clinically resembles breast carcinoma. The lesion occurs in non-lactating young women, and the incidence rate is rising. Surgical resection is the main treatment, but cannot prevent recurrence of the disease. Disfigurement or removal of breast after the operations can cause marked physical and psychological distress. The etiology of plasma cell mastitis is unclear up till now. It is therefore necessary to investigate further the underlying immunological changes of the disease. The lesions of plasma cell mastitis removed from patients through aseptic operation were mixed with normal saline into homogenate tube machine (homogenate tubes were disinfected and sterilized prior to treatment). The mixture was homogenized at medium speed and grinded in ultrasonic cell disruptor. The homogenate obtained was made into oil emulsion with Freund's adjuvant. Thirty female BALB/c mice (6 weeks after sexual maturity) were divided into five groups A-E: group A was blank control; group B was normal saline control; group C was inoculated with 0.02 ml water-in-oil emulsion; group D was inoculated with 0.04 ml water-in-oil emulsion; group E was complete Freund's adjuvant control. Pathology results showed that mouse mammary gland acinar cells remained integral without any abnormal changes observed in control groups A and B. Experimental groups C and D showed dilation of mouse mammary ductal tissue with a large number of epithelial cells and debris in the lumen, and fibrosis around ducts accompanied by large duct cells, neutrophils, lymphocytes, and especially plasma cell infiltration. Pathological changes were observed in 3 (50%) mice and 5 (83.3%) mice in group C and D respectively. In group E, neutrophil infiltration in mammary gland was observed in 5 mice, but neither infiltration of plasma cells nor other abnormal pathological changes were observed. The lesions of patient with plasma cell mastitis could make the female BALB/c mice experience the similar clinical and pathological manifestation. High-dose group can successfully establish a mouse model of plasma cell mastitis.

Ultra-structural study of insulin granules in pancreatic β-cells of db/db mouse by scanning transmission electron microscopy tomography.

PubMed

Xue, Yanhong; Zhao, Wei; Du, Wen; Zhang, Xiang; Ji, Gang; Ying, Wang; Xu, Tao

2012-07-01

Insulin granule trafficking is a key step in the secretion of glucose-stimulated insulin from pancreatic β-cells. The main feature of type 2 diabetes (T2D) is the failure of pancreatic β-cells to secrete sufficient amounts of insulin to maintain normal blood glucose levels. In this work, we developed and applied tomography based on scanning transmission electron microscopy (STEM) to image intact insulin granules in the β-cells of mouse pancreatic islets. Using three-dimensional (3D) reconstruction, we found decreases in both the number and the grey level of insulin granules in db/db mouse pancreatic β-cells. Moreover, insulin granules were closer to the plasma membrane in diabetic β-cells than in control cells. Thus, 3D ultra-structural tomography may provide new insights into the pathology of insulin secretion in T2D.

Hypothalamic stem cells control ageing speed partly through exosomal miRNAs.

PubMed

Zhang, Yalin; Kim, Min Soo; Jia, Baosen; Yan, Jingqi; Zuniga-Hertz, Juan Pablo; Han, Cheng; Cai, Dongsheng

2017-08-03

It has been proposed that the hypothalamus helps to control ageing, but the mechanisms responsible remain unclear. Here we develop several mouse models in which hypothalamic stem/progenitor cells that co-express Sox2 and Bmi1 are ablated, as we observed that ageing in mice started with a substantial loss of these hypothalamic cells. Each mouse model consistently displayed acceleration of ageing-like physiological changes or a shortened lifespan. Conversely, ageing retardation and lifespan extension were achieved in mid-aged mice that were locally implanted with healthy hypothalamic stem/progenitor cells that had been genetically engineered to survive in the ageing-related hypothalamic inflammatory microenvironment. Mechanistically, hypothalamic stem/progenitor cells contributed greatly to exosomal microRNAs (miRNAs) in the cerebrospinal fluid, and these exosomal miRNAs declined during ageing, whereas central treatment with healthy hypothalamic stem/progenitor cell-secreted exosomes led to the slowing of ageing. In conclusion, ageing speed is substantially controlled by hypothalamic stem cells, partially through the release of exosomal miRNAs.

LSD1 demethylase and the methyl-binding protein PHF20L1 prevent SET7 methyltransferase-dependent proteolysis of the stem-cell protein SOX2.

PubMed

Zhang, Chunxiao; Hoang, Nam; Leng, Feng; Saxena, Lovely; Lee, Logan; Alejo, Salvador; Qi, Dandan; Khal, Anthony; Sun, Hong; Lu, Fei; Zhang, Hui

2018-03-09

The pluripotency-controlling stem-cell protein SRY-box 2 (SOX2) plays a pivotal role in maintaining the self-renewal and pluripotency of embryonic stem cells and also of teratocarcinoma or embryonic carcinoma cells. SOX2 is monomethylated at lysine 119 (Lys-119) in mouse embryonic stem cells by the SET7 methyltransferase, and this methylation triggers ubiquitin-dependent SOX2 proteolysis. However, the molecular regulators and mechanisms controlling SET7-induced SOX2 proteolysis are unknown. Here, we report that in human ovarian teratocarcinoma PA-1 cells, methylation-dependent SOX2 proteolysis is dynamically regulated by the LSD1 lysine demethylase and a methyl-binding protein, PHD finger protein 20-like 1 (PHF20L1). We found that LSD1 not only removes the methyl group from monomethylated Lys-117 (equivalent to Lys-119 in mouse SOX2), but it also demethylates monomethylated Lys-42 in SOX2, a reaction that SET7 also regulated and that also triggered SOX2 proteolysis. Our studies further revealed that PHF20L1 binds both monomethylated Lys-42 and Lys-117 in SOX2 and thereby prevents SOX2 proteolysis. Down-regulation of either LSD1 or PHF20L1 promoted SOX2 proteolysis, which was prevented by SET7 inactivation in both PA-1 and mouse embryonic stem cells. Our studies also disclosed that LSD1 and PHF20L1 normally regulate the growth of pluripotent mouse embryonic stem cells and PA-1 cells by preventing methylation-dependent SOX2 proteolysis. In conclusion, our findings reveal an important mechanism by which the stability of the pluripotency-controlling stem-cell protein SOX2 is dynamically regulated by the activities of SET7, LSD1, and PHF20L1 in pluripotent stem cells. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Isolation and characterization of neural stem cells from dystrophic mdx mouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Annese, Tiziana; Corsi, Patrizia; Ruggieri, Simona

The blood-brain barrier (BBB) is altered in mdx mouse, an animal model to study Duchenne muscular dystrophy (DMD). Our previous work demonstrated that perivascular glial endfeet control the selective exchanges between blood and neuropil as well as the BBB development and integrity; the alterations of dystrophin and dystrophin-associated protein complex (DAPs) in the glial cells of mdx mouse, parallel damages of the BBB and increase in vascular permeability. The aim of this study was to improve our knowledge about brain cellular components in the mdx mouse through the isolation, for the first time, of the adult neural stem cells (ANSCs).more » We characterized them by FACS, electron microscopy, confocal immunofluorescence microscopy, Real Time-PCR and western blotting, and we studied the expression of the DAPs aquaporin-4 (AQP4), potassium channel Kir4.1, α- and β-dystroglycan (αDG, βDG), α-syntrophin (αSyn), and short dystrophin isoform Dp71 proteins. The results showed that the mdx ANSCs expressed CD133 and Nestin receptor as the control ones, but showed a reduction in Notch receptor and altered cell proliferation with an increment in the apoptotic nuclei. Ultrastructurally, they appeared 50% size reduced compared to control ones, with a few cytoplasmic organelles. Moreover, the mdx ANSCs are devoid in full length dystrophin 427, and they expressed post-transcriptional reduction in the Dp71 in parallel with the ubiquitin proteasome activation, and decrement of DAPs proteins which appeared diffused in the cytoplasm and not polarized on the stem cells plasmamembrane, as prevalently observed in the controls. Overall, these results indicate that structural and molecular alterations affect the neural stem cells in the dystrophic brain, whose increased apoptosis and reduced Dp71 and DAPs proteins expression, together with loss in Dp427 dystrophin, could be responsible of the altered mdx glial maintenance and differentiation and consequent failure in the vessels barrier control occurring in the adult dystrophic brain.« less

Recovery of deficient homologous recombination in Brca2-depleted mouse cells by wild-type Rad51 expression.

PubMed

Lee, Shauna A; Roques, Céline; Magwood, Alissa C; Masson, Jean-Yves; Baker, Mark D

2009-02-01

The BRCA2 tumor suppressor is important in maintaining genomic stability. BRCA2 is proposed to control the availability, cellular localization and DNA binding activity of the central homologous recombination protein, RAD51, with loss of BRCA2 resulting in defective homologous recombination. Nevertheless, the roles of BRCA2 in regulating RAD51 and how other proteins implicated in RAD51 regulation, such as RAD52 and RAD54 function relative to BRCA2 is not known. In this study, we tested whether defective homologous recombination in Brca2-depleted mouse hybridoma cells could be rectified by expression of mouse Rad51 or the Rad51-interacting mouse proteins, Rad52 and Rad54. In the Brca2-depleted cells, defective homologous recombination can be restored by over-expression of wild-type mouse Rad51, but not mouse Rad52 or Rad54. Correction of the homologous recombination defect requires Rad51 ATPase activity. A sizeable fraction ( approximately 50%) of over-expressed wild-type Rad51 is nuclear localized. The restoration of homologous recombination in the presence of a low (i.e., non-functional) level of Brca2 by wild-type Rad51 over-expression is unexpected. We suggest that Rad51 may access the nuclear compartment in a Brca2-independent manner and when Rad51 is over-expressed, the normal requirement for Brca2 control over Rad51 function in homologous recombination is dispensable. Our studies support loss of Rad51 function as a critical underlying factor in the homologous recombination defect in the Brca2-depleted cells.

Zinc stimulates glucose oxidation and glycemic control by modulating the insulin signaling pathway in human and mouse skeletal muscle cell lines.

PubMed

Norouzi, Shaghayegh; Adulcikas, John; Sohal, Sukhwinder Singh; Myers, Stephen

2018-01-01

Zinc is a metal ion that is an essential cell signaling molecule. Highlighting this, zinc is an insulin mimetic, activating cellular pathways that regulate cellular homeostasis and physiological responses. Previous studies have linked dysfunctional zinc signaling with several disease states including cancer, obesity, cardiovascular disease and type 2 diabetes. The present study evaluated the insulin-like effects of zinc on cell signaling molecules including tyrosine, PRSA40, Akt, ERK1/2, SHP-2, GSK-3β and p38, and glucose oxidation in human and mouse skeletal muscle cells. Insulin and zinc independently led to the phosphorylation of these proteins over a 60-minute time course in both mouse and human skeletal muscle cells. Similarly, utilizing a protein array we identified that zinc could active the phosphorylation of p38, ERK1/2 and GSK-3B in human and ERK1/2 and GSK-3B in mouse skeletal muscle cells. Glucose oxidation assays were performed on skeletal muscle cells treated with insulin, zinc, or a combination of both and resulted in a significant induction of glucose consumption in mouse (p<0.01) and human (p<0.05) skeletal muscle cells when treated with zinc alone. Insulin, as expected, increased glucose oxidation in mouse (p<0.001) and human (0.001) skeletal muscle cells, however the combination of zinc and insulin did not augment glucose consumption in these cells. Zinc acts as an insulin mimetic, activating key molecules implicated in cell signaling to maintain glucose homeostasis in mouse and human skeletal muscle cells. Zinc is an important metal ion implicated in several biological processes. The role of zinc as an insulin memetic in activating key signaling molecules involved in glucose homeostasis could provide opportunities to utilize this ion therapeutically in treating disorders associated with dysfunctional zinc signaling.

Apoptosis of mouse MS-2 fibrosarcoma cells induced by photodynamic therapy with Zn (II)-phthalocyanine.

PubMed

Zhou, C; Shunji, C; Jinsheng, D; Junlin, L; Jori, G; Milanesi, C

1996-05-01

The destructive process of mouse MS-2 fibrosarcoma induced by photodynamic therapy (PDT) with liposome-administered Zn(II)-phthalocyanine (ZnPc) was studied by electron microscopy. Pronounced ultrastructural changes characteristic of apoptosis were observed for several tumour cells, including early occurrence of condensation and margination of chromatin, disappearance of nuclear pores, karyopyknosis, karyorrhexis, protuberance formation at the cell surface and cell fragmentation. The findings indicate that apoptosis was involved in the process of tumour cell death induced by ZnPc-PDT. The detailed mechanism and pathways controlling this phenomenon need to be elucidated further.

Construction of a Dual-Fluorescence Reporter System to Monitor the Dynamic Progression of Pluripotent Cell Differentiation.

PubMed

Sun, Wu-Sheng; Chun, Ju-Lan; Do, Jeong-Tae; Kim, Dong-Hwan; Ahn, Jin-Seop; Kim, Min-Kyu; Hwang, In-Sul; Kwon, Dae-Jin; Hwang, Seong-Soo; Lee, Jeong-Woong

2016-01-01

Oct4 is a crucial germ line-specific transcription factor expressed in different pluripotent cells and downregulated in the process of differentiation. There are two conserved enhancers, called the distal enhancer (DE) and proximal enhancer (PE), in the 5' upstream regulatory sequences (URSs) of the mouse Oct4 gene, which were demonstrated to control Oct4 expression independently in embryonic stem cells (ESCs) and epiblast stem cells (EpiSCs). We analyzed the URSs of the pig Oct4 and identified two similar enhancers that were highly consistent with the mouse DE and PE. A dual-fluorescence reporter was later constructed by combining a DE-free- Oct4 -promoter-driven EGFP reporter cassette with a PE-free- Oct4 -promoter-driven mCherry reporter cassette. Then, it was tested in a mouse ESC-like cell line (F9) and a mouse EpiSC-like cell line (P19) before it is formally used for pig. As a result, a higher red fluorescence was observed in F9 cells, while green fluorescence was primarily detected in P19 cells. This fluorescence expression pattern in the two cell lines was consistent with that in the early naïve pluripotent state and late primed pluripotent state during differentiation of mouse ESCs. Hence, this reporter system will be a convenient tool for screening out ESC-like naïve pluripotent stem cells from other metastable state cells in a heterogenous population.

Mouse glucocorticoid-induced tumor necrosis factor receptor ligand is costimulatory for T cells

PubMed Central

Tone, Masahide; Tone, Yukiko; Adams, Elizabeth; Yates, Stephen F.; Frewin, Mark R.; Cobbold, Stephen P.; Waldmann, Herman

2003-01-01

Recently, agonist antibodies to glucocorticoid-induced tumor necrosis factor receptor (GITR) (tumor necrosis factor receptor superfamily 18) have been shown to neutralize the suppressive activity of CD4+CD25+ regulatory T cells. It was anticipated that this would be the role of the physiological ligand. We have identified and expressed the gene for mouse GITR ligand and have confirmed that its interaction with GITR reverses suppression by CD4+CD25+ T cells. It also, however, provides a costimulatory signal for the antigen-driven proliferation of naïve T cells and polarized T helper 1 and T helper 2 clones. RT-PCR and mAb staining revealed mouse GITR ligand expression in dendritic cells, macrophages, and B cells. Expression was controlled by the transcription factor NF-1 and potentially by alternative splicing of mRNA destabilization sequences. PMID:14608036

Activation of mouse and human peroxisome proliferator-activated receptor alpha by perfluoroalkyl acids of different functional groups and chain lengths.

PubMed

Wolf, Cynthia J; Takacs, Margy L; Schmid, Judith E; Lau, Christopher; Abbott, Barbara D

2008-11-01

Perfluoroalkyl acids (PFAAs) are surfactants used in consumer products and persist in the environment. Some PFAAs elicit adverse effects on rodent development and survival. PFAAs can activate peroxisome proliferator-activated receptor alpha (PPARalpha) and may act via PPARalpha to produce some of their effects. This study evaluated the ability of numerous PFAAs to induce mouse and human PPARalpha activity in a transiently transfected COS-1 cell assay. COS-1 cells were transfected with either a mouse or human PPARalpha receptor-luciferase reporter plasmid. After 24 h, cells were exposed to either negative controls (water or dimethyl sulfoxide, 0.1%); positive control (WY-14643, PPARalpha agonist); perfluorooctanoic acid or perfluorononanoic acid at 0.5-100 microM; perfluorobutanoic acid, perfluorohexanoic acid, perfluorohexane sulfonate, or perfluorodecanoic acid (PFDA) at 5-100 microM; or perfluorobutane sulfonate or perfluorooctane sulfonate at 1-250 microM. After 24 h of exposure, luciferase activity from the plasmid was measured. Each PFAA activated both mouse and human PPARalpha in a concentration-dependent fashion, except PFDA with human PPARalpha. Activation of PPARalpha by PFAA carboxylates was positively correlated with carbon chain length, up to C9. PPARalpha activity was higher in response to carboxylates compared to sulfonates. Activation of mouse PPARalpha was generally higher compared to that of human PPARalpha. We conclude that, in general, (1) PFAAs of increasing carbon backbone chain lengths induce increasing activity of the mouse and human PPARalpha with a few exceptions, (2) PFAA carboxylates are stronger activators of mouse and human PPARalpha than PFAA sulfonates, and (3) in most cases, the mouse PPARalpha appears to be more sensitive to PFAAs than the human PPARalpha in this model.

Serine protease activity in m-1 cortical collecting duct cells.

PubMed

Liu, Lian; Hering-Smith, Kathleen S; Schiro, Faith R; Hamm, L Lee

2002-04-01

An apical serine protease, channel-activating protease 1 (CAP1), augments sodium transport in A6 cells. Prostasin, a novel serine protease originally purified from seminal fluid, has been proposed to be the mammalian ortholog of CAP1. We have recently found functional evidence for a similar protease activity in the M-1 cortical collecting duct cell line. The purposes of the present studies were to determine whether prostasin (or CAP1) is present in collecting duct cells by use of mouse M-1 cells, to sequence mouse prostasin, and to further characterize the identity of the serine protease activity and additional functional features in M-1 cells. Using mouse expressed sequence tag sequences that are highly homologous to the published human prostasin sequence as templates, reverse transcription-polymerase chain reaction and RACE (rapid amplification of cDNA ends) were used to sequence mouse prostasin mRNA, which shows 99% identical to published mouse CAP1 sequence. A single 1800-bp transcript was found by Northern analysis, and this was not altered by aldosterone. Equivalent short-circuit current (I(eq)), which represents sodium transport in these cells, dropped to 59+/-3% of control value within 1 hour of incubation with aprotinin, a serine protease inhibitor. Trypsin increased the I(eq) in aprotinin-treated cells to the value of the control group within 5 minutes. Application of aprotinin not only inhibited amiloride sensitive I(eq) but also reduced transepithelial resistance (R(te)) to 43+/-2%, an effect not expected with simple inhibition of sodium channels. Trypsin partially reversed the effect of aprotinin on R(te). Another serine protease inhibitor, soybean trypsin inhibitor (STI), decreased I(eq) in M-1 cells. STI inhibited I(eq) gradually over 6 hours, and the inhibition of I(eq) by 2 inhibitors was additive. STI decreased transepithelial resistance much less than did aprotinin. Neither aldosterone nor dexamethasone significantly augmented protease activity or prostasin mRNA levels, and in fact, dexamethasone decreased prostasin mRNA expression. In conclusion, although prostasin is present in M-1 cells and probably augments sodium transport in these cells, serine proteases probably have other effects (eg, resistance) in the collecting duct in addition to effects on sodium channels. Steroids do not alter these effects in M-1 cells. Additional proteases are likely also present in mouse collecting duct cells.

Vesicular monoamine transporter-1 (VMAT-1) mRNA and immunoreactive proteins in mouse brain.

PubMed

Ashe, Karen M; Chiu, Wan-Ling; Khalifa, Ahmed M; Nicolas, Antoine N; Brown, Bonnie L; De Martino, Randall R; Alexander, Clayton P; Waggener, Christopher T; Fischer-Stenger, Krista; Stewart, Jennifer K

2011-01-01

Vesicular monoamine transporter 1 (VMAT-1) mRNA and protein were examined (1) to determine whether adult mouse brain expresses full-length VMAT-1 mRNA that can be translated to functional transporter protein and (2) to compare immunoreactive VMAT-1 proteins in brain and adrenal. VMAT-1 mRNA was detected in mouse brain with RT-PCR. The cDNA was sequenced, cloned into an expression vector, transfected into COS-1 cells, and cell protein was assayed for VMAT-1 activity. Immunoreactive proteins were examined on western blots probed with four different antibodies to VMAT-1. Sequencing confirmed identity of the entire coding sequences of VMAT-1 cDNA from mouse medulla oblongata/pons and adrenal to a Gen-Bank reference sequence. Transfection of the brain cDNA into COS-1 cells resulted in transporter activity that was blocked by the VMAT inhibitor reserpine and a proton ionophore, but not by tetrabenazine, which has a high affinity for VMAT-2. Antibodies to either the C- or N- terminus of VMAT-1 detected two proteins (73 and 55 kD) in transfected COS-1 cells. The C-terminal antibodies detected both proteins in extracts of mouse medulla/pons, cortex, hypothalamus, and cerebellum but only the 73 kD protein and higher molecular weight immunoreactive proteins in mouse adrenal and rat PC12 cells, which are positive controls for rodent VMAT-1. These findings demonstrate that a functional VMAT-1 mRNA coding sequence is expressed in mouse brain and suggest processing of VMAT-1 protein differs in mouse adrenal and brain.

Dynamic 3D culture promotes spontaneous embryonic stem cell differentiation in vitro.

PubMed

Gerlach, Jörg C; Hout, Mariah; Edsbagge, Josefina; Björquist, Petter; Lübberstedt, Marc; Miki, Toshio; Stachelscheid, Harald; Schmelzer, Eva; Schatten, Gerald; Zeilinger, Katrin

2010-02-01

Spontaneous in vitro differentiation of mouse embryonic stem cells (mESC) is promoted by a dynamic, three-dimensional (3D), tissue-density perfusion technique with continuous medium perfusion and exchange in a novel four-compartment, interwoven capillary bioreactor. We compared ectodermal, endodermal, and mesodermal immunoreactive tissue structures formed by mESC at culture day 10 with mouse fetal tissue development at gestational day E9.5. The results show that the bioreactor cultures more closely resemble mouse fetal tissue development at gestational day E9.5 than control mESC cultured in Petri dishes.

Loss of BID Delays FASL-Induced Cell Death of Mouse Neutrophils and Aggravates DSS-Induced Weight Loss.

PubMed

Wicki, Simone; Gurzeler, Ursina; Corazza, Nadia; Genitsch, Vera; Wong, Wendy Wei-Lynn; Kaufmann, Thomas

2018-02-28

Neutrophils are key players in the early defense against invading pathogens. Due to their potent effector functions, programmed cell death of activated neutrophils has to be tightly controlled; however, its underlying mechanisms remain unclear. Fas ligand (FASL/CD95L) has been shown to induce neutrophil apoptosis, which is accelerated by the processing of the BH3-only protein BH3 interacting domain death agonist (BID) to trigger mitochondrial apoptotic events, and been attributed a regulatory role during viral and bacterial infections. Here, we show that, in accordance with previous works, mouse neutrophils underwent caspase-dependent apoptosis in response to FASL, and that this cell death was significantly delayed upon loss of BID. However, pan-caspase inhibition failed to protect mouse neutrophils from FASL-induced apoptosis and caused a switch to RIPK3-dependent necroptotic cell death. Intriguingly, such a switch was less evident in the absence of BID, particularly under inflammatory conditions. Delayed neutrophil apoptosis has been implicated in several auto-inflammatory diseases, including inflammatory bowel disease. We show that neutrophil and macrophage driven acute dextran sulfate sodium (DSS) induced colitis was slightly more aggravated in BID-deficient mice, based on significantly increased weight loss compared to wild-type controls. Taken together, our data support a central role for FASL > FAS and BID in mouse neutrophil cell death and further underline the anti-inflammatory role of BID.

Loss of BID Delays FASL-Induced Cell Death of Mouse Neutrophils and Aggravates DSS-Induced Weight Loss

PubMed Central

Wicki, Simone; Gurzeler, Ursina; Corazza, Nadia; Genitsch, Vera

2018-01-01

Neutrophils are key players in the early defense against invading pathogens. Due to their potent effector functions, programmed cell death of activated neutrophils has to be tightly controlled; however, its underlying mechanisms remain unclear. Fas ligand (FASL/CD95L) has been shown to induce neutrophil apoptosis, which is accelerated by the processing of the BH3-only protein BH3 interacting domain death agonist (BID) to trigger mitochondrial apoptotic events, and been attributed a regulatory role during viral and bacterial infections. Here, we show that, in accordance with previous works, mouse neutrophils underwent caspase-dependent apoptosis in response to FASL, and that this cell death was significantly delayed upon loss of BID. However, pan-caspase inhibition failed to protect mouse neutrophils from FASL-induced apoptosis and caused a switch to RIPK3-dependent necroptotic cell death. Intriguingly, such a switch was less evident in the absence of BID, particularly under inflammatory conditions. Delayed neutrophil apoptosis has been implicated in several auto-inflammatory diseases, including inflammatory bowel disease. We show that neutrophil and macrophage driven acute dextran sulfate sodium (DSS) induced colitis was slightly more aggravated in BID-deficient mice, based on significantly increased weight loss compared to wild-type controls. Taken together, our data support a central role for FASL > FAS and BID in mouse neutrophil cell death and further underline the anti-inflammatory role of BID. PMID:29495595

The PD-1/B7-H1 pathway modulates the natural killer cells versus mouse glioma stem cells.

PubMed

Huang, Bo Yuan; Zhan, Yi Ping; Zong, Wen Jing; Yu, Chun Jiang; Li, Jun Fa; Qu, Yan Ming; Han, Song

2015-01-01

Glioblastoma multiforme (GBM) is the most malignant primary type of brain tumor in adults. There has been increased focus on the immunotherapies to treat GBM patients, the therapeutic value of natural killer (NK) cells is still unknown. Programmed death-1 (PD-1) is a major immunological checkpoint that can negatively regulate the T-cell-mediated immune response. We tested the combination of the inhibiting the PD-1/B7H1 pathway with a NK-cell mediated immune response in an orthotopic mouse model of GBM. Mouse glioma stem cells (GL261GSCs) and mouse NK cells were isolated and identified. A lactate dehydrogenase (LDH) assay was perfomed to detect the cytotoxicity of NK cells against GL261GSCs. GL261GSCs were intracranially implanted into mice, and the mice were stratified into 3 treatment groups: 1) control, 2) NK cells treatment, and 3) PD-1 inhibited NK cells treatment group. Overall survival was quantified, and animal magnetic resonance imaging (MRI) was performed to determine tumor growth. The brains were harvested after the mice were euthanized, and immunohistochemistry against CD45 and PCNA was performed. The mouse NK cells were identified as 90% CD3- NK1.1+CD335+ by flow cytometric analysis. In the LDH assay, the ratios of the damaged GL261GSCs, with the E:T ratios of 2.5:1, 5:1, and 10:1, were as follows: 1) non-inhibited group: 7.42%, 11.31%, and 15.1%, 2) B7H1 inhibited group: 14.75%, 18.25% and 29.1%, 3) PD-1 inhibited group: 15.53%, 19.21% and 29.93%, 4) double inhibited group: 33.24%, 42.86% and 54.91%. In the in vivo experiments, the mice in the PD-1 inhibited NK cells treatment group and IL-2-stimulated-NK cells treatment group displayed a slowest tumor growth (F = 308.5, P<0.01) and a slower tumor growth compared with control group (F = 118.9, P<0.01), respectively. The median survival of the mice in the three groups were as follows: 1) conrol group: 29 days, 2) NK cells treatment group: 35 days (P = 0.0012), 3) PD-1 inhibited NK cells treatment group: 44 days (P = 0.0024). Immunologic data of PCNA-positive cell ratios and CD45-positive cell ratios of the tumor specimens in the three groups were as follows: 1) control group: 65.72% (PCNA) and 0.92% (CD45), 2) NK treatment group: 27.66% (PCNA) and 13.46% (CD45), and 3) PD-1 inhibited NK cells treatment group: 13.66% (PCNA) and 23.66% (CD45) (P<0.001). The results demonstrated that blockade of PD-1/B7H1 pathway could promote mouse NK cells to kill the GL261GSCs, and the PD-1-inhibited NK cells could be a feasible immune therapeutic approach against GBM.

Optical control of GPR40 signalling in pancreatic β-cells.

PubMed

Frank, James Allen; Yushchenko, Dmytro A; Fine, Nicholas H F; Duca, Margherita; Citir, Mevlut; Broichhagen, Johannes; Hodson, David J; Schultz, Carsten; Trauner, Dirk

2017-11-01

Fatty acids activate GPR40 and K + channels to modulate β-cell function. Herein, we describe the design and synthesis of FAAzo-10 , a light-controllable GPR40 agonist based on Gw-9508. FAAzo-10 is a potent GPR40 agonist in the trans -configuration and can be inactivated on isomerization to cis with UV-A light. Irradiation with blue light reverses this effect, allowing FAAzo-10 activity to be cycled ON and OFF with a high degree of spatiotemporal precision. In dissociated primary mouse β-cells, FAAzo-10 also inactivates voltage-activated and ATP-sensitive K + channels, and allows us to control glucose-stimulated Ca 2+ oscillations in whole islets with light. As such, FAAzo-10 is a useful tool to study the complex effects, with high specificity, which FA-derivatives such as Gw-9508 exert at multiple targets in mouse β-cells.

Targeting Phosphoinositide 3-Kinase γ in Airway Smooth Muscle Cells to Suppress Interleukin-13-Induced Mouse Airway Hyperresponsiveness

PubMed Central

Jiang, Haihong; Xie, Yan; Abel, Peter W.; Toews, Myron L.; Townley, Robert G.; Casale, Thomas B.

2012-01-01

We recently reported that phosphoinositide 3-kinase γ (PI3Kγ) directly regulates airway smooth muscle (ASM) contraction by modulating Ca2+ oscillations. Because ASM contraction plays a critical role in airway hyperresponsiveness (AHR) of asthma, the aim of the present study was to determine whether targeting PI3Kγ in ASM cells could suppress AHR in vitro and in vivo. Intranasal administration into mice of interleukin-13 (IL-13; 10 μg per mouse), a key pathophysiologic cytokine in asthma, induced AHR after 48 h, as assessed by invasive tracheostomy. Intranasal administration of a broad-spectrum PI3K inhibitor or a PI3Kγ-specific inhibitor 1 h before AHR assessment attenuated IL-13 effects. Airway responsiveness to bronchoconstrictor agonists was also examined in precision-cut mouse lung slices pretreated without or with IL-13 for 24 h. Acetylcholine and serotonin dose-response curves indicated that IL-13-treated lung slices had a 40 to 50% larger maximal airway constriction compared with controls. Furthermore, acetylcholine induced a larger initial Ca2+ transient and increased Ca2+ oscillations in IL-13-treated primary mouse ASM cells compared with control cells, correlating with increased cell contraction. As expected, PI3Kγ inhibitor treatment attenuated IL-13-augmented airway contractility of lung slices and ASM cell contraction. In both control and IL-13-treated ASM cells, small interfering RNA-mediated knockdown of PI3Kγ by 70% only reduced the initial Ca2+ transient by 20 to 30% but markedly attenuated Ca2+ oscillations and contractility of ASM cells by 50 to 60%. This report is the first to demonstrate that PI3Kγ in ASM cells is important for IL-13-induced AHR and that acute treatment with a PI3Kγ inhibitor can ameliorate AHR in a murine model of asthma. PMID:22543031

Fetoprotein Derived Short Peptide Coated Nanostructured Amphiphilic Surfaces for Targeting Mouse Breast Cancer Cells

NASA Astrophysics Data System (ADS)

Brown, Alexandra M.; Miranda-Alarćon, Yoliem S.; Knoll, Grant A.; Santora, Anthony M.; Banerjee, Ipsita A.

In this work, self-assembled tumor targeting nanostructured surfaces were developed from a newly designed amphiphile by conjugating boc protected isoleucine with 2,2‧ ethylenedioxy bis ethylamine (IED). To target mouse mammary tumor cells, a short peptide sequence derived from the human alpha-fetoprotein (AFP), LSEDKLLACGEG was attached to the self-assembled nanostructures. Tumor targeting and cell proliferation were examined in the presence of nanoscale assemblies. To further obliterate mouse breast tumor cells, the chemotherapeutic drug tamoxifen was then entrapped into the nanoassemblies. Our studies indicated that the targeting systems were able to efficiently encapsulate and release tamoxifen. Cell proliferation studies showed that IED-AFP peptide loaded with tamoxifen decreased the proliferation of breast cancer cells while in the presence of the IED-AFP peptide nanoassemblies alone, the growth was relatively slower. In the presence of human dermal fibroblasts however cell proliferation continued similar to controls. Furthermore, the nanoscale assemblies were found to induce apoptosis in mouse breast cancer cells. To examine live binding interactions, SPR analysis revealed that tamoxifen encapsulated IED-AFP peptide nanoassemblies bound to the breast cancer cells more efficiently compared to unencapsulated assemblies. Thus, we have developed nanoscale assemblies that can specifically bind to and target tumor cells, with increased toxicity in the presence of a chemotherapeutic drug.

Pituitary Androgen Receptor Signalling Regulates Prolactin but Not Gonadotrophins in the Male Mouse

PubMed Central

O’Hara, Laura; Curley, Michael; Tedim Ferreira, Maria; Cruickshanks, Lyndsey; Milne, Laura; Smith, Lee B.

2015-01-01

Production of the androgen testosterone is controlled by a negative feedback loop within the hypothalamic-pituitary-gonadal (HPG) axis. Stimulation of testicular Leydig cells by pituitary luteinising hormone (LH) is under the control of hypothalamic gonadotrophin releasing hormone (GnRH), while suppression of LH secretion by the pituitary is controlled by circulating testosterone. Exactly how androgens exert their feedback control of gonadotrophin secretion (and whether this is at the level of the pituitary), as well as the role of AR in other pituitary cell types remains unclear. To investigate these questions, we exploited a transgenic mouse line (Foxg1Cre/+; ARfl/y) which lacks androgen receptor in the pituitary gland. Both circulating testosterone and gonadotrophins are unchanged in adulthood, demonstrating that AR signalling is dispensable in the male mouse pituitary for testosterone-dependent regulation of LH secretion. In contrast, Foxg1Cre/+; ARfl/y males have a significant increase in circulating prolactin, suggesting that, rather than controlling gonadotrophins, AR-signalling in the pituitary acts to suppress aberrant prolactin production in males. PMID:25799562

Resveratrol protects mouse embryonic stem cells from ionizing radiation by accelerating recovery from DNA strand breakage.

PubMed

Denissova, Natalia G; Nasello, Cara M; Yeung, Percy L; Tischfield, Jay A; Brenneman, Mark A

2012-01-01

Resveratrol has elicited many provocative anticancer effects in laboratory animals and cultured cells, including reduced levels of oxidative DNA damage, inhibition of tumor initiation and progression and induction of apoptosis in tumor cells. Use of resveratrol as a cancer-preventive agent in humans will require that its anticancer effects not be accompanied by damage to normal tissue stem or progenitor cells. In mouse embryonic stem cells (mESC) or early mouse embryos exposed to ethanol, resveratrol has been shown to suppress apoptosis and promote survival. However, in cells exposed to genotoxic stress, survival may come at the expense of genome stability. To learn whether resveratrol can protect stem cells from DNA damage and to study its effects on genomic integrity, we exposed mESC pretreated with resveratrol to ionizing radiation (IR). Forty-eight hours pretreatment with a comparatively low concentration of resveratrol (10 μM) improved survival of mESC >2-fold after exposure to 5 Gy of X-rays. Cells pretreated with resveratrol sustained the same levels of reactive oxygen species and DNA strand breakage after IR as mock-treated controls, but repaired DNA damage more rapidly and resumed cell division sooner. Frequencies of IR-induced mutation at a chromosomal reporter locus were not increased in cells pretreated with resveratrol as compared with controls, indicating that resveratrol can improve viability in mESC after DNA damage without compromising genomic integrity.

[Effect of Panax ginseng components on the differentiation of mouse embryonic stem cells into cardiac-like cells].

PubMed

Sasaki, Toshiya; Oh, Ki-Bong; Matsuoka, Hideaki; Saito, Mikako

2008-03-01

Bioactive compounds that may control the specific differentiation from mouse embryonic stem (ES) cells into cardiac-like cells have been screened from herbal medicines. Among seven preparations, Panax ginseng was found to promote the differentiation into beating cells and to sustain their beating for longer than the control. Active compounds were found in its water-soluble fraction. Although they were not isolated, their candidates were surveyed in 42 compounds selected from the database of P. ginseng. Finally we found that vitamin B12 (VB12) and methionine were active. VB12 accelerated the differentiation into beating cells and made the beating rate constantly 100%. Moreover, VB12 was effective in the recovery of beating that was inhibited by spermine action. The mechanism of action of VB12 is discussed in termo of the relevance of intercellular electrical signal transduction.

High-fidelity Glucagon-CreER mouse line generated by CRISPR-Cas9 assisted gene targeting.

PubMed

Ackermann, Amanda M; Zhang, Jia; Heller, Aryel; Briker, Anna; Kaestner, Klaus H

2017-03-01

α-cells are the second most prominent cell type in pancreatic islets and are responsible for producing glucagon to increase plasma glucose levels in times of fasting. α-cell dysfunction and inappropriate glucagon secretion occur in both type 1 and type 2 diabetes. Thus, there is growing interest in studying both normal function and pathophysiology of α-cells. However, tools to target gene ablation or activation specifically of α-cells have been limited, compared to those available for β-cells. Previous Glucagon-Cre and Glucagon-CreER transgenic mouse lines have suffered from transgene silencing, and the only available Glucagon-CreER "knock-in" mouse line results in glucagon haploinsufficiency, which can confound the interpretation of gene deletion analyses. Therefore, we sought to develop a Glucagon-CreER T2 mouse line that would maintain normal glucagon expression and would be less susceptible to transgene silencing. We utilized CRISPR-Cas9 technology to insert an IRES-CreER T2 sequence into the 3' UTR of the Glucagon ( Gcg ) locus in mouse embryonic stem cells (ESCs). Targeted ESC clones were then injected into mouse blastocysts to obtain Gcg-CreER T2 mice. Recombination efficiency in GCG + pancreatic α-cells and glucagon-like peptide 1 positive (GLP1 + ) enteroendocrine L-cells was measured in Gcg-CreER T2 ; Rosa26-LSL-YFP mice injected with tamoxifen during fetal development and adulthood. Tamoxifen injection of Gcg-CreER T2 ; Rosa26-LSL-YFP mice induced high recombination efficiency of the Rosa26-LSL-YFP locus in perinatal and adult α-cells (88% and 95%, respectively), as well as in first-wave fetal α-cells (36%) and adult enteroendocrine L-cells (33%). Mice homozygous for the Gcg-CreER T2 allele were phenotypically normal. We successfully derived a Gcg-CreER T2 mouse line that expresses CreER T2 in pancreatic α-cells and enteroendocrine L-cells without disrupting preproglucagon gene expression. These mice will be a useful tool for performing temporally controlled genetic manipulation specifically in these cell types.

Strain preservation of experimental animals: vitrification of two-cell stage embryos for multiple mouse strains.

PubMed

Eto, Tomoo; Takahashi, Riichi; Kamisako, Tsutomu

2015-04-01

Strain preservation of experimental animals is crucial for experimental reproducibility. Maintaining complete animal strains, however, is costly and there is a risk for genetic mutations as well as complete loss due to disasters or illness. Therefore, the development of effective vitrification techniques for cryopreservation of multiple experimental animal strains is important. We examined whether a vitrification method using cryoprotectant solutions, P10 and PEPeS, is suitable for preservation of multiple inbred and outbred mouse strains. First, we investigated whether our vitrification method using cryoprotectant solutions was suitable for two-cell stage mouse embryos. In vitro development of embryos exposed to the cryoprotectant solutions was similar to that of fresh controls. Further, the survival rate of the vitrified embryos was extremely high (98.1%). Next, we collected and vitrified two-cell stage embryos of 14 mouse strains. The average number of embryos obtained from one female was 7.3-33.3. The survival rate of vitrified embryos ranged from 92.8% to 99.1%, with no significant differences among mouse strains. In vivo development did not differ significantly between fresh controls and vitrified embryos of each strain. For strain preservation using cryopreserved embryos, two offspring for inbred lines and one offspring for outbred lines must be produced from two-cell stage embryos collected from one female. The expected number of surviving fetuses obtained from embryos collected from one female of either the inbred or outbred strains ranged from 2.9 to 19.5. The findings of the present study indicated that this vitrification method is suitable for strain preservation of multiple mouse strains. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Moesin Is a Biomarker for the Assessment of Genotoxic Carcinogens in Mouse Lymphoma

PubMed Central

Lee, Yoen Jung; Choi, In-Kwon; Sheen, Yhun Yhong; Park, Sue Nie; Kwon, Ho Jeong

2012-01-01

1,2-Dibromoethane and glycidol are well known genotoxic carcinogens, which have been widely used in industry. To identify a specific biomarker for these carcinogens in cells, the cellular proteome of L5178Y mouse lymphoma cells treated with these compounds was analyzed by 2-dimensional gel electrophoresis (2-DE) and MALDI-TOF mass spectrometry (MS). Of 50 protein spots showing a greater than 1.5-fold increase or decrease in intensity compared to control cells on a 2-D gel, we focused on the candidate biomarker moesin. Western analysis using monoclonal rabbit anti-moesin confirmed the identity of the protein and its increased level of expression upon exposure to the carcinogenic compounds. Moesin expression also increased in cells treated with six additional genotoxic carcinogens, verifying that moesin could serve as a biomarker to monitor phenotypic change upon exposure to genotoxic carcinogens in L5178Y mouse lymphoma cells. PMID:22358511

Moesin is a biomarker for the assessment of genotoxic carcinogens in mouse lymphoma.

PubMed

Lee, Yoen Jung; Choi, In-Kwon; Sheen, Yhun Yhong; Park, Sue Nie; Kwon, Ho Jeong

2012-02-01

1,2-Dibromoethane and glycidol are well known genotoxic carcinogens, which have been widely used in industry. To identify a specific biomarker for these carcinogens in cells, the cellular proteome of L5178Y mouse lymphoma cells treated with these compounds was analyzed by 2-dimensional gel electrophoresis (2-DE) and MALDI-TOF mass spectrometry (MS). Of 50 protein spots showing a greater than 1.5-fold increase or decrease in intensity compared to control cells on a 2-D gel, we focused on the candidate biomarker moesin. Western analysis using monoclonal rabbit anti-moesin confirmed the identity of the protein and its increased level of expression upon exposure to the carcinogenic compounds. Moesin expression also increased in cells treated with six additional genotoxic carcinogens, verifying that moesin could serve as a biomarker to monitor phenotypic change upon exposure to genotoxic carcinogens in L5178Y mouse lymphoma cells.

VSVΔG/EBOV GP-induced innate protection enhances natural killer cell activity to increase survival in a lethal mouse adapted Ebola virus infection.

PubMed

Williams, Kinola J N; Qiu, Xiangguo; Fernando, Lisa; Jones, Steven M; Alimonti, Judie B

2015-02-01

Members of the species Zaire ebolavirus cause severe hemorrhagic fever with up to a 90% mortality rate in humans. The VSVΔG/EBOV GP vaccine has provided 100% protection in the mouse, guinea pig, and nonhuman primate (NHP) models, and has also been utilized as a post-exposure therapeutic to protect mice, guinea pigs, and NHPs from a lethal challenge of Ebola virus (EBOV). EBOV infection causes rapid mortality in human and animal models, with death occurring as early as 6 days after infection, suggesting a vital role for the innate immune system to control the infection before cells of the adaptive immune system can assume control. Natural killer (NK) cells are the predominant cell of the innate immune response, which has been shown to expand with VSVΔG/EBOV GP treatment. In the current study, an in vivo mouse model of the VSVΔG/EBOV GP post-exposure treatment was used for a mouse adapted (MA)-EBOV infection, to determine the putative VSVΔG/EBOV GP-induced protective mechanism of NK cells. NK depletion studies demonstrated that mice with NK cells survive longer in a MA-EBOV infection, which is further enhanced with VSVΔG/EBOV GP treatment. NK cell mediated cytotoxicity and IFN-γ secretion was significantly higher with VSVΔG/EBOV GP treatment. Cell mediated cytotoxicity assays and perforin knockout mice experiments suggest that there are perforin-dependent and -independent mechanisms involved. Together, these data suggest that NK cells play an important role in VSVΔG/EBOV GP-induced protection of EBOV by increasing NK cytotoxicity, and IFN-γ secretion.

Development and Function of CD94-Deficient Natural Killer Cells

PubMed Central

Orr, Mark T.; Wu, Jun; Fang, Min; Sigal, Luis J.; Spee, Pieter; Egebjerg, Thomas; Dissen, Erik; Fossum, Sigbjørn; Phillips, Joseph H.; Lanier, Lewis L.

2010-01-01

The CD94 transmembrane-anchored glycoprotein forms disulfide-bonded heterodimers with the NKG2A subunit to form an inhibitory receptor or with the NKG2C or NKG2E subunits to assemble a receptor complex with activating DAP12 signaling proteins. CD94 receptors expressed on human and mouse NK cells and T cells have been proposed to be important in NK cell tolerance to self, play an important role in NK cell development, and contribute to NK cell-mediated immunity to certain infections including human cytomegalovirus. We generated a gene-targeted CD94-deficient mouse to understand the role of CD94 receptors in NK cell biology. CD94-deficient NK cells develop normally and efficiently kill NK cell-susceptible targets. Lack of these CD94 receptors does not alter control of mouse cytomegalovirus, lymphocytic choriomeningitis virus, vaccinia virus, or Listeria monocytogenes. Thus, the expression of CD94 and its associated NKG2A, NKG2C, and NKG2E subunits is dispensable for NK cell development, education, and many NK cell functions. PMID:21151939

Development and function of CD94-deficient natural killer cells.

PubMed

Orr, Mark T; Wu, Jun; Fang, Min; Sigal, Luis J; Spee, Pieter; Egebjerg, Thomas; Dissen, Erik; Fossum, Sigbjørn; Phillips, Joseph H; Lanier, Lewis L

2010-12-03

The CD94 transmembrane-anchored glycoprotein forms disulfide-bonded heterodimers with the NKG2A subunit to form an inhibitory receptor or with the NKG2C or NKG2E subunits to assemble a receptor complex with activating DAP12 signaling proteins. CD94 receptors expressed on human and mouse NK cells and T cells have been proposed to be important in NK cell tolerance to self, play an important role in NK cell development, and contribute to NK cell-mediated immunity to certain infections including human cytomegalovirus. We generated a gene-targeted CD94-deficient mouse to understand the role of CD94 receptors in NK cell biology. CD94-deficient NK cells develop normally and efficiently kill NK cell-susceptible targets. Lack of these CD94 receptors does not alter control of mouse cytomegalovirus, lymphocytic choriomeningitis virus, vaccinia virus, or Listeria monocytogenes. Thus, the expression of CD94 and its associated NKG2A, NKG2C, and NKG2E subunits is dispensable for NK cell development, education, and many NK cell functions.

Induction of neural differentiation by electrically stimulated gene expression of NeuroD2.

PubMed

Mie, Masayasu; Endoh, Tamaki; Yanagida, Yasuko; Kobatake, Eiry; Aizawa, Masuo

2003-02-13

Regulation of cell differentiation is an important assignment for cellular engineering. One of the techniques for regulation is gene transfection into undifferentiated cells. Transient expression of NeuroD2, one of neural bHLH transcription factors, converted mouse N1E-115 neuroblastoma cells into differentiated neurons. The regulation of neural bHLH expression should be a novel strategy for cell differentiation. In this study, we tried to regulate neural differentiation by NeuroD2 gene inserted under the control of heat shock protein-70 (HSP) promoter, which can be activated by electrical stimulation. Mouse neuroblastoma cell line, N1E-115, was stably transfected with expression vector containing mouse NeuroD2 cDNA under HSP promoter. Transfected cells were cultured on the electrode surface and applied electrical stimulation. After stimulation, NeuroD2 expression was induced, and transfected cells adopt a neuronal morphology at 3 days after stimulation. These results suggest that neural differentiation can be induced by electrically stimulated gene expression of NeuroD2.

Eliminating Glutamatergic Input onto Horizontal Cells Changes the Dynamic Range and Receptive Field Organization of Mouse Retinal Ganglion Cells.

PubMed

Ströh, Sebastian; Puller, Christian; Swirski, Sebastian; Hölzel, Maj-Britt; van der Linde, Lea I S; Segelken, Jasmin; Schultz, Konrad; Block, Christoph; Monyer, Hannah; Willecke, Klaus; Weiler, Reto; Greschner, Martin; Janssen-Bienhold, Ulrike; Dedek, Karin

2018-02-21

In the mammalian retina, horizontal cells receive glutamatergic inputs from many rod and cone photoreceptors and return feedback signals to them, thereby changing photoreceptor glutamate release in a light-dependent manner. Horizontal cells also provide feedforward signals to bipolar cells. It is unclear, however, how horizontal cell signals also affect the temporal, spatial, and contrast tuning in retinal output neurons, the ganglion cells. To study this, we generated a genetically modified mouse line in which we eliminated the light dependency of feedback by deleting glutamate receptors from mouse horizontal cells. This genetic modification allowed us to investigate the impact of horizontal cells on ganglion cell signaling independent of the actual mode of feedback in the outer retina and without pharmacological manipulation of signal transmission. In control and genetically modified mice (both sexes), we recorded the light responses of transient OFF-α retinal ganglion cells in the intact retina. Excitatory postsynaptic currents (EPSCs) were reduced and the cells were tuned to lower temporal frequencies and higher contrasts, presumably because photoreceptor output was attenuated. Moreover, receptive fields of recorded cells showed a significantly altered surround structure. Our data thus suggest that horizontal cells are responsible for adjusting the dynamic range of retinal ganglion cells and, together with amacrine cells, contribute to the center/surround organization of ganglion cell receptive fields in the mouse. SIGNIFICANCE STATEMENT Horizontal cells represent a major neuronal class in the mammalian retina and provide lateral feedback and feedforward signals to photoreceptors and bipolar cells, respectively. The mode of signal transmission remains controversial and, moreover, the contribution of horizontal cells to visual processing is still elusive. To address the question of how horizontal cells affect retinal output signals, we recorded the light responses of transient OFF-α retinal ganglion cells in a newly generated mouse line. In this mouse line, horizontal cell signals were no longer modulated by light. With light response recordings, we show that horizontal cells increase the dynamic range of retinal ganglion cells for contrast and temporal changes and contribute to the center/surround organization of their receptive fields. Copyright © 2018 the authors 0270-6474/18/382015-14$15.00/0.

Role of YAP activation in nuclear receptor CAR-mediated proliferation of mouse hepatocytes.

PubMed

Abe, Taiki; Amaike, Yuto; Shizu, Ryota; Takahashi, Miki; Kano, Makoto; Hosaka, Takuomi; Sasaki, Takamitsu; Kodama, Susumu; Matsuzawa, Atsushi; Yoshinari, Kouichi

2018-06-08

Constitutive androstane receptor (CAR) is a xenobiotic-responsive nuclear receptor that is highly expressed in the liver. CAR activation induces hepatocyte proliferation and hepatocarcinogenesis in rodents, but the mechanisms remain unclear. In this study, we investigated the association of CAR-dependent cell proliferation with Yes-associated protein (YAP), which is a transcriptional cofactor controlling organ size and cell growth through the interaction with various transcriptional factors including TEAD. In mouse livers, TCPOBOP (a mouse CAR activator) treatment increased the nuclear YAP accumulation and mRNA levels of YAP target genes as well as cell-cycle related genes along with liver hypertrophy and verteporfin (an inhibitor of YAP/TEAD interaction) cotreatment tended to attenuate them. Furthermore, in cell-based reporter gene assays, CAR activation enhanced the YAP/TEAD-dependent transcription. To investigate the role of YAP/TEAD activation in the CAR-dependent hepatocyte proliferation, we sought to establish an in vitro system completely reproducing CAR-dependent cell proliferation. Since CAR was only slightly expressed in cultured mouse primary hepatocytes compared to mouse livers and no proliferation was observed after treatment with TCPOBOP, we overexpressed CAR using mouse CAR expressing adenovirus (Ad-mCAR-V5) in mouse primary hepatocytes. Ad-mCAR-V5 infection and TCPOBOP treatment induced hepatocyte proliferation. Similar results were obtained with immortalized normal mouse hepatocytes as well. In the established in vitro system, CAR-dependent proliferation was strongly inhibited by Yap knockdown and completely abolished by verteporfin treatment. Our present results obtained in in vivo and in vitro experiments suggest that YAP/TEAD activation plays key roles in CAR-dependent proliferation of murine hepatocytes.

Effects of various freezing containers for vitrification freezing on mouse oogenesis.

PubMed

Kim, Ji Chul; Kim, Jae Myeoung; Seo, Byoung Boo

2016-01-01

In the present study, various freezing containers were tested for mouse embryos of respective developmental stages; embryos were vitrified and then their survival rate and developmental rate were monitored. Mouse two cell, 8 cell, and blastula stage embryos underwent vitrification freezing-thawing and then their recovery rate, survival rate, development rate, and hatching rate were investigated. EM-grid, OPS, and cryo-loop were utilized for vitrification freezing-thawing of mouse embryos. It was found that recovery rate and survival rate were higher in the group of cryo-loop compared to those of EM-grid (p < 0.05). Embryonic development rate, two cell embryos to blastocyst, as well as hatching rate were higher in the control group compared to the EM-grid group and OPS group (p < 0.05), yet no difference was noted between the control group and cryo-loop group. Development rate and hatching rate of eight cell morulae and blastocysts were all lower in the treatment groups than the control group whilst hatching rate of blastocysts was higher in the control group compared to the groups of EM-grid and OPS (p < 0.05); although the cryo-loop group was shown to be slightly higher than other groups, it was not statistically significant. In the study, we investigate effects of freezing containers on vitrified embryos of respective developmental stages; it was demonstrated that higher developmental rate was shown in more progressed (or developed) embryos with more blastomeres. There was however, no difference in embryonic development rate was shown amongst containers. Taken together, further additional studies are warranted with regards to 1) manipulation techniques of embryos for various vitrification freezing containers and 2) preventive measures against contamination via liquid nitrogen.

Regional Fluctuation in the Functional Consequence of LINE-1 Insertion in the Mitf Gene: The Black Spotting Phenotype Arisen from the Mitfmi-bw Mouse Lacking Melanocytes.

PubMed

Takeda, Kazuhisa; Hozumi, Hiroki; Ohba, Koji; Yamamoto, Hiroaki; Shibahara, Shigeki

2016-01-01

Microphthalmia-associated transcription factor (Mitf) is a key regulator for differentiation of melanoblasts, precursors to melanocytes. The mouse homozygous for the black-eyed white (Mitfmi-bw) allele is characterized by the white-coat color and deafness with black eyes due to the lack of melanocytes. The Mitfmi-bw allele carries LINE-1, a retrotransposable element, which results in the Mitf deficiency. Here, we have established the black spotting mouse that was spontaneously arisen from the homozygous Mitfmi-bw mouse lacking melanocytes. The black spotting mouse shows multiple black patches on the white coat, with age-related graying. Importantly, each black patch also contains hair follicles lacking melanocytes, whereas the white-coat area completely lacks melanocytes. RT-PCR analyses of the pigmented patches confirmed that the LINE-1 insertion is retained in the Mitf gene of the black spotting mouse, thereby excluding the possibility of the somatic reversion of the Mitfmi-bw allele. The immunohistochemical analysis revealed that the staining intensity for beta-catenin was noticeably lower in hair follicles lacking melanocytes of the homozygous Mitfmi-bw mouse and the black spotting mouse, compared to the control mouse. In contrast, the staining intensity for beta-catenin and cyclin D1 was higher in keratinocytes of the black spotting mouse, compared to keratinocytes of the control mouse and the Mitfmi-bw mouse. Moreover, the keratinocyte layer appears thicker in the Mitfmi-bw mouse, with the overexpression of Ki-67, a marker for cell proliferation. We also show that the presumptive black spots are formed by embryonic day 15.5. Thus, the black spotting mouse provides the unique model to explore the molecular basis for the survival and death of developing melanoblasts and melanocyte stem cells in the epidermis. These results indicate that follicular melanocytes are responsible for maintaining the epidermal homeostasis; namely, the present study has provided evidence for the link between melanocyte development and the epidermal microenvironment.

Development of the mouse vestibular system in the absence of gravity perception

NASA Technical Reports Server (NTRS)

Smith, Michael; Yuan Wang, Xiang; Wolgemuth, Debra J.; Murashov, Alexander K.

2003-01-01

The tilted mutant mouse, which lacks otoconia in the inner ear, was used to study development of the mouse vestibular system in the absence of gravity perception. Otoconia are dense particles composed of proteins and calcium carbonate crystals suspended in the gelatinous macular membrane. They enhance, and are largely responsible for, sensitivity to gravity. Morphometric analysis of the vestibular ganglion showed that the mutant developed more slowly than the normal controls, both in rate of development and cell number, particularly during the first week of post-natal development. The mutant ganglia also exhibited a reduction of cells during the first 6 days of post-natal development.

Mouse A6-positive hepatic oval cells derived from embryonic stem cells.

PubMed

Yin, Dong-zhi; Cai, Ji-ye; Zheng, Qi-chang; Chen, Zheng-wei; Zhao, Jing-xian; Yuan, You-neng

2014-02-01

Oval cells have a potential to differentiate into a variety of cell lineages including hepatocytes and biliary epithelia. Several models have been established to activate the oval cells by incorporating a variety of toxins and carcinogens, alone or combined with surgical treatment. Those models are obviously not suitable for the study on human hepatic oval cells. It is necessary to establish a new and efficient model to study the human hepatic oval cells. In this study, the hepatocyte growth factor (HGF) and epidermal growth factor (EGF) were used to induce differentiation of mouse embryonic stem (ES) cells into hepatic oval cells. We first confirmed that hepatic oval cells derived from ES cells, which are bipotential, do exist during the course of mouse ES cells' differentiation into hepatic parenchymal cells. RT-PCR and transmission electron microscopy were applied in this study. The ratio of Sca-1+/CD34+ cells sorted by FACS in the induction group was increased from day 4 and reached the maximum on the day 8, whereas that in the control group remained at a low level. The differentiation ratio of Sca-1+/CD34+ cells in the induction group was significantly higher than that in the control group. About 92.48% of the sorted Sca-1+/CD34+ cells on the day 8 were A6 positive. Highly purified A6+/Sca-1+/CD34+ hepatic oval cells derived from ES cells could be obtained by FACS. The differentiation ratio of hepatic oval cells in the induction group (up to 4.46%) was significantly higher than that in the control group. The number of hepatic oval cells could be increased significantly by HGF and EGF. The study also examined the ultrastructures of ES-derived hepatic oval cells' membrane surface by atomic force microscopy. The ES-derived hepatic oval cells cultured and sorted by our protocols may be available for the future clinical application.

CD44-positive cells are candidates for astrocyte precursor cells in developing mouse cerebellum.

PubMed

Cai, Na; Kurachi, Masashi; Shibasaki, Koji; Okano-Uchida, Takayuki; Ishizaki, Yasuki

2012-03-01

Neural stem cells are generally considered to be committed to becoming precursor cells before terminally differentiating into either neurons or glial cells during neural development. Neuronal and oligodendrocyte precursor cells have been identified in several areas in the murine central nervous system. The presence of astrocyte precursor cells (APCs) is not so well understood. The present study provides several lines of evidence that CD44-positive cells are APCs in the early postnatal mouse cerebellum. In developing mouse cerebellum, CD44-positive cells, mostly located in the white matter, were positive for the markers of the astrocyte lineage, but negative for the markers of mature astrocytes. CD44-positive cells were purified from postnatal cerebellum by fluorescence-activated cell sorting and characterized in vitro. In the absence of any signaling molecule, many cells died by apoptosis. The surviving cells gradually expressed glial fibrillary acidic protein, a marker for mature astrocytes, indicating that differentiation into mature astrocytes is the default program for these cells. The cells produced no neurospheres nor neurons nor oligodendrocytes under any condition examined, indicating these cells are not neural stem cells. Leukemia inhibitory factor greatly promoted astrocytic differentiation of CD44-positive cells, whereas bone morphogenetic protein 4 (BMP4) did not. Fibroblast growth factor-2 was a potent mitogen for these cells, but was insufficient for survival. BMP4 inhibited activation of caspase-3 and greatly promoted survival, suggesting a novel role for BMP4 in the control of development of astrocytes in cerebellum. We isolated and characterized only CD44 strongly positive large cells and discarded small and/or CD44 weakly positive cells in this study. Further studies are necessary to characterize these cells to help determine whether CD44 is a selective and specific marker for APCs in the developing mouse cerebellum. In conclusion, we succeeded in preparing APC candidates from developing mouse cerebellum, characterized them in vitro, and found that BMPs are survival factors for these cells.

[PKA-regulated phosphorylation status of S149 and S321 sites of CDC25B inhibits mitosis of fertilized mouse eggs].

PubMed

Xiao, Jian-Ying; Liu, Chao; Sun, Xiao-Han; Yu, Bing-Zhi

2012-02-25

To further test whether protein kinase A (PKA) can affect the mitotic cell cycle, one-cell stage mouse embryos at S phase (22 h after hCG injection) were incubated in M16 medium containing various concentrations of H-89, a PKA inhibitor. With increasing concentrations of H-89 (0-50 μmol/L), the G(2) phase of eggs was decreased and the cleavage rate was accelerated. A concentration of 40 μmol/L H-89 led to all of the mouse eggs entering the M phase of mitosis. Furthermore, to study the role of PKA in regulating the phosphorylation status of S149 and S321 sites of cell division cycle 25B (CDC25B) on one-cell stage fertilized mouse eggs, pBSK-CDC25B-WT, pBSK-CDC25B-S149A, pBSK-CDC25B-S321A and pBSK-CDC25B-S149A/S321A were transcribed into mRNAs in vitro, then mRNAs were microinjected into S phase of mouse fertilized eggs and cultured in M16 medium pretreated with H-89. Then, the cleavage of fertilized eggs, maturation promoting factor (MPF) activity and phosphorylation status of CDC2-Tyr15 were observed. In the presence of 40 μmol/L H-89, the cleavage rate of fertilized eggs in CDC25B-S/A-mRNAs and CDC25B-WT-mRNA injected groups was significantly higher than that in the control groups, and the peak of MPF activity appeared in the CDC25B-S/A-mRNAs and CDC25B-WT-mRNA injected groups earlier than that in the control groups. CDC2-Tyr15 phosphorylation state was consistent with MPF activity. In conclusion, the present study suggests that PKA regulates the early development of mouse embryos by phosphorylation of S149 and S321 of CDC25B, which plays an important role in the regulation of G(2)/M transition in the mitotic cell cycle of fertilized mouse eggs.

["In vitro" interactions between influenza virus and mouse lung alveolar macrophages (author's transl)].

PubMed

Lemercier, G; Mavet, S; Burckhart, M F; Fontanges, R

1979-01-01

Interactions between influenza virus A/PR/8/34 (H0N1) and Balb/c mouse lung alveolar macrophages have been studied in vitro. One day after initiation of alveolar macrophage culture in 35 mm Falcon dishes, the virus suspension was allowed to adsorb to the cells for 1 h. Detachment of cells from the plastic substrate, morphological changes in adherent cells and decreased phagocytosis of heat-killed Candida albicans occured slowly as compared to control cultures. These facts appeared to be directly correlated to the concentration of viruses in the inoculum. Data yielded by virus titrations, electron microscopy and immunofluorescence suggest that mouse lung alveolar macrophages are able to take up a large amount of viral particles and inhibit their replication, allowing only an abortive viral cycle.

Unique roles of estrogen-dependent Pten control in epithelial cell homeostasis of mouse vagina.

PubMed

Miyagawa, S; Sato, M; Sudo, T; Yamada, G; Iguchi, T

2015-02-19

Numerous studies support a role of phosphatase and tensin homolog deleted from chromosome 10 (Pten) as a tumor suppressor gene that controls epithelial cell homeostasis to prevent tumor formation. Mouse vaginal epithelium cyclically exhibits cell proliferation and differentiation in response to estrogen and provides a unique model for analyzing homeostasis of stratified squamous epithelia. We analyzed vaginal epithelium-specific Pten conditional knockout (CKO) mice to provide new insights into Pten/phosphoinositide-3-kinase (PI3K)/Akt function. The vaginal epithelium of ovariectomized (OVX) mice (control) was composed of 1-2 layers of cuboidal cells, whereas OVX CKO mice exhibited epithelial hyperplasia in the suprabasal cells with increased cell mass and mucin production. This is possibly due to misactivation of mammalian target of rapamycin and mitogen-activated protein kinase. Intriguingly, estrogen administration to OVX Pten CKO mice induced stratification and keratinized differentiation in the vaginal epithelium, as in estrogen-treated controls. We found that Pten is exclusively expressed in the suprabasal cells in the absence of estrogens, whereas estrogen administration induced Pten expression in the basal cells. This suggests that Pten acts to prevent excessive cell proliferation as in the case of other squamous tissues. Thus, Pten exhibits a dual role on the control of vaginal homeostasis, depending on whether estrogens are present or absent. Our results provide new insights into how Pten functions in tissue homeostasis.

Modulation of Glucose Transporter 1 (GLUT1) Expression Levels Alters Mouse Mammary Tumor Cell Growth In Vitro and In Vivo

PubMed Central

Young, Christian D.; Lewis, Andrew S.; Rudolph, Michael C.; Ruehle, Marisa D.; Jackman, Matthew R.; Yun, Ui J.; Ilkun, Olesya; Pereira, Renata; Abel, E. Dale; Anderson, Steven M.

2011-01-01

Tumor cells exhibit an altered metabolism characterized by elevated aerobic glycolysis and lactate secretion which is supported by an increase in glucose transport and consumption. We hypothesized that reducing or eliminating the expression of the most prominently expressed glucose transporter(s) would decrease the amount of glucose available to breast cancer cells thereby decreasing their metabolic capacity and proliferative potential. Of the 12 GLUT family glucose transporters expressed in mice, GLUT1 was the most abundantly expressed at the RNA level in the mouse mammary tumors from MMTV-c-ErbB2 mice and cell lines examined. Reducing GLUT1 expression in mouse mammary tumor cell lines using shRNA or Cre/Lox technology reduced glucose transport, glucose consumption, lactate secretion and lipid synthesis in vitro without altering the concentration of ATP, as well as reduced growth on plastic and in soft agar. The growth of tumor cells with reduced GLUT1 expression was impaired when transplanted into the mammary fat pad of athymic nude mice in vivo. Overexpression of GLUT1 in a cell line with low levels of endogenous GLUT1 increased glucose transport in vitro and enhanced growth in nude mice in vivo as compared to the control cells with very low levels of GLUT1. These studies demonstrate that GLUT1 is the major glucose transporter in mouse mammary carcinoma models overexpressing ErbB2 or PyVMT and that modulation of the level of GLUT1 has an effect upon the growth of mouse mammary tumor cell lines in vivo. PMID:21826239

Adeno-associated virus-mediated gene delivery into the scala media of the normal and deafened adult mouse ear.

PubMed

Kilpatrick, L A; Li, Q; Yang, J; Goddard, J C; Fekete, D M; Lang, H

2011-06-01

Murine models are ideal for studying cochlear gene transfer, as many hearing loss-related mutations have been discovered and mapped within the mouse genome. However, because of the small size and delicate nature, the membranous labyrinth of the mouse is a challenging target for the delivery of viral vectors. To minimize injection trauma, we developed a procedure for the controlled release of adeno-associated viruses (AAVs) into the scala media of adult mice. This procedure poses minimal risk of injury to structures of the cochlea and middle ear, and allows for near-complete preservation of low and middle frequency hearing. In this study, transduction efficiency and cellular specificity of AAV vectors (serotypes 1, 2, 5, 6 and 8) were investigated in normal and drug-deafened ears. Using the cytomegalovirus promoter to drive gene expression, a variety of cell types were transduced successfully, including sensory hair cells and supporting cells, as well as cells in the auditory nerve and spiral ligament. Among all five serotypes, inner hair cells were the most effectively transduced cochlear cell type. All five serotypes of AAV vectors transduced cells of the auditory nerve, though serotype 8 was the most efficient vector for transduction. Our findings indicate that efficient AAV inoculation (via the scala media) can be performed in adult mouse ears, with hearing preservation a realistic goal. The procedure we describe may also have applications for intra-endolymphatic drug delivery in many mouse models of human deafness.

Adeno-associated virus-mediated gene delivery into the scala media of the normal and deafened adult mouse ear

PubMed Central

Kilpatrick, Lauren A.; Li, Qian; Yang, John; Goddard, John C; Fekete, Donna M.; Lang, Hainan

2010-01-01

Murine models are ideal for studying cochlear gene transfer as many hearing loss-related mutations have been discovered and mapped within the mouse genome. However, due to its small size and delicate nature, the membranous labyrinth of the mouse is a challenging target for delivery of viral vectors. To minimize injection trauma, we developed a procedure for the controlled release of adeno-associated viruses (AAV) into the scala media of adult mice. This procedure poses minimal risk of injury to structures of the cochlea and middle ear and allows for near-complete preservation of low and middle frequency hearing. In the present study, transduction efficiency and cellular specificity of AAV vectors (serotypes 1, 2, 5, 6, and 8) were investigated in normal and drug-deafened ears. Using the cytomegalovirus (CMV) promoter to drive gene expression, a variety of cell types were transduced successfully, including sensory hair cells and supporting cells, as well as cells in the auditory nerve and spiral ligament. Among all five serotypes, inner hair cells (IHCs) were the most effectively transduced cochlear cell type. All five serotypes of AAV vectors transduced cells of the auditory nerve, though serotype 8 was the most efficient vector for transduction. Our findings indicate that efficient AAV inoculation (via the scala media) can be performed in adult mouse ears, with hearing preservation a realistic goal. The procedure we describe may also have applications for intra-endolymphatic drug delivery in many mouse models of human deafness. PMID:21209625

An efficient method for generation of bi-allelic null mutant mouse embryonic stem cells and its application for investigating epigenetic modifiers

PubMed Central

Cho, Lily Ting-yin; Andrews, Robert; Carroll, Thomas; Iyer, Vivek; Tate, Peri; Rosen, Barry; Stunnenberg, Hendrik G.; Fisher, Amanda G.; Skarnes, William C.

2017-01-01

Abstract Mouse embryonic stem (ES) cells are a popular model system to study biological processes, though uncovering recessive phenotypes requires inactivating both alleles. Building upon resources from the International Knockout Mouse Consortium (IKMC), we developed a targeting vector for second allele inactivation in conditional-ready IKMC ‘knockout-first’ ES cell lines. We applied our technology to several epigenetic regulators, recovering bi-allelic targeted clones with a high efficiency of 60% and used Flp recombinase to restore expression in two null cell lines to demonstrate how our system confirms causality through mutant phenotype reversion. We designed our strategy to select against re-targeting the ‘knockout-first’ allele and identify essential genes in ES cells, including the histone methyltransferase Setdb1. For confirmation, we exploited the flexibility of our system, enabling tamoxifen inducible conditional gene ablation while controlling for genetic background and tamoxifen effects. Setdb1 ablated ES cells exhibit severe growth inhibition, which is not rescued by exogenous Nanog expression or culturing in naive pluripotency ‘2i’ media, suggesting that the self-renewal defect is mediated through pluripotency network independent pathways. Our strategy to generate null mutant mouse ES cells is applicable to thousands of genes and repurposes existing IKMC Intermediate Vectors. PMID:28981838

Lack of huntingtin promotes neural stem cells differentiation into glial cells while neurons expressing huntingtin with expanded polyglutamine tracts undergo cell death.

PubMed

Conforti, Paola; Camnasio, Stefano; Mutti, Cesare; Valenza, Marta; Thompson, Morgan; Fossale, Elisa; Zeitlin, Scott; MacDonald, Marcy E; Zuccato, Chiara; Cattaneo, Elena

2013-02-01

Huntington's disease (HD) is a neurodegenerative disorder that affects muscle coordination and diminishes cognitive abilities. The genetic basis of the disease is an expansion of CAG repeats in the Huntingtin (Htt) gene. Here we aimed to generate a series of mouse neural stem (NS) cell lines that carried varying numbers of CAG repeats in the mouse Htt gene (Hdh CAG knock-in NS cells) or that had Hdh null alleles (Hdh knock-out NS cells). Towards this end, Hdh CAG knock-in mouse ES cell lines that carried an Htt gene with 20, 50, 111, or 140 CAG repeats or that were Htt null were neuralized and converted into self-renewing NS cells. The resulting NS cell lines were immunopositive for the neural stem cell markers NESTIN, SOX2, and BLBP and had similar proliferative rates and cell cycle distributions. After 14 days in vitro, wild-type NS cells gave rise to cultures composed of 70% MAP2(+) neurons and 30% GFAP(+) astrocytes. In contrast, NS cells with expanded CAG repeats underwent neuronal cell death, with only 38%±15% of the MAP2(+) cells remaining at the end of the differentiation period. Cell death was verified by increased caspase 3/7 activity on day 14 of the neuronal differentiation protocol. Interestingly, Hdh knock-out NS cells treated using the same neuronal differentiation protocol showed a dramatic increase in the number of GFAP(+) cells on day 14 (61%±20% versus 24%±10% in controls), and a massive decrease of MAP2(+) neurons (30%±11% versus 64%±17% in controls). Both Hdh CAG knock-in NS cells and Hdh knock-out NS cells showed reduced levels of Bdnf mRNA during neuronal differentiation, in agreement with data obtained previously in HD mouse models and in post-mortem brain samples from HD patients. We concluded that Hdh CAG knock-in and Hdh knock-out NS cells have potential as tools for investigating the roles of normal and mutant HTT in differentiated neurons and glial cells of the brain. Copyright © 2012 Elsevier Inc. All rights reserved.

F-actin mechanics control spindle centring in the mouse zygote

NASA Astrophysics Data System (ADS)

Chaigne, Agathe; Campillo, Clément; Voituriez, Raphaël; Gov, Nir S.; Sykes, Cécile; Verlhac, Marie-Hélène; Terret, Marie-Emilie

2016-01-01

Mitotic spindle position relies on interactions between astral microtubules nucleated by centrosomes and a rigid cortex. Some cells, such as mouse oocytes, do not possess centrosomes and astral microtubules. These cells rely only on actin and on a soft cortex to position their spindle off-centre and undergo asymmetric divisions. While the first mouse embryonic division also occurs in the absence of centrosomes, it is symmetric and not much is known on how the spindle is positioned at the exact cell centre. Using interdisciplinary approaches, we demonstrate that zygotic spindle positioning follows a three-step process: (1) coarse centring of pronuclei relying on the dynamics of an F-actin/Myosin-Vb meshwork; (2) fine centring of the metaphase plate depending on a high cortical tension; (3) passive maintenance at the cell centre. Altogether, we show that F-actin-dependent mechanics operate the switch between asymmetric to symmetric division required at the oocyte to embryo transition.

Generation and characterization of PDGFRα-GFPCreERT2 knock-In mouse line.

PubMed

Miwa, Hiroyuki; Era, Takumi

2015-05-01

Platelet-derived growth factor (PDGF) and its receptor play an important role in embryogenesis. PDGF receptor α (PDGFRα) is expressed specifically in the embryonic day 7.5 (E7.5) mesoderm and in the E9.5 neural crest among other tissues. PDGFRα-expressing cells and their descendants are involved in the formation of various tissues. To trace PDGFRα-expressing cells in vivo, we generated a knock-in mouse line that expressed a fusion protein of green fluorescent protein (GFP), Cre recombinase (Cre), and mutated estrogen receptor ligand-binding domain (ERT2) under the control of the PDGFRα promoter. In these mice, Cre activity in PDGFRα-expressing cells could be induced by tamoxifen treatment. Taken together, our results suggest that the knock-in mouse line generated here could be useful for studying PDGFRα-expressing cells and their descendants in vivo at various stages of development. © 2015 Wiley Periodicals, Inc.

Saccharin and Cyclamate Inhibit Binding of Epidermal Growth Factor

NASA Astrophysics Data System (ADS)

Lee, L. S.

1981-02-01

The binding of 125I-labeled mouse epidermal growth factor (EGF) to 18 cell lines, including HeLa (human carcinoma), MDCK (dog kidney cells), HTC (rat hepatoma), K22 (rat liver), HF (human foreskin), GM17 (human skin fibroblasts), XP (human xeroderma pigmentosum fibroblasts), and 3T3-L1 (mouse fibroblasts), was inhibited by saccharin and cyclamate. The human cells were more sensitive to inhibition by these sweeteners than mouse or rat cells. EGF at doses far above the physiological levels reversed the inhibition in rodent cells but not in HeLa cells. In HeLa cells, the doses of saccharin and cyclamate needed for 50% inhibition were 3.5 and 9.3 mg/ml, respectively. Glucose, 2-deoxyglucose, sucrose, and xylitol did not inhibit EGF binding. Previous studies have shown that phorbol esters, strongly potent tumor promoters, also inhibit EGF binding to tissue culture cells. To explain the EGF binding inhibition by such greatly dissimilar molecules as phorbol esters, saccharin, and cyclamate, it is suggested that they operate through the activation of a hormone response control unit.

In vitro toxicity assay of cisplatin on mouse acute lymphoblastic leukaemia and spermatogonial stem cells.

PubMed

Shabani, R; Ashtari, K; Behnam, B; Izadyar, F; Asgari, H; Asghari Jafarabadi, M; Ashjari, M; Asadi, E; Koruji, M

2016-06-01

Testicular cancer is the most common cancer affecting men in reproductive age, and cisplatin is one of the major helpful chemotherapeutic agents for treatment of this cancer. In addition, exposure of testes cancer cells to cisplatin could potentially eliminate tumour cells from germ cells in patients. The aim of this study was to evaluate the effect of cisplatin on viability of mouse acute lymphoblastic leukaemia cell line (EL-4) and neonatal mouse spermatogonial cells in vitro. In this study, the isolated spermatogonial stem cells (SSC) and EL-4 were divided into six groups including control (received medium), sham (received DMSO in medium) and experimental groups which received different doses of cisplatin (0.5, 5, 10 and 15 μg ml(-1) ). Cells viability was evaluated with MTT assay. The identity of the cultured cells was confirmed by the expression of specific markers. Our finding showed that viability of both SSC and EL-4 cells was reduced with the dose of 15 μg/ml when compared to the control group (P ≤ 0.05). Also, the differences between the IC50 in doses 10 and 15 μg/ml at different time were significant (P ≤ 0.05). The number of TUNEL-positive cells was increased, and the BAX and caspase-3 expressions were upregulated in EL4 cells for group that received an effective dose of cisplatin). In conclusion, despite the dramatic effects of cisplatin on both cells, spermatogonial stem cells could form colony in culture. © 2015 Blackwell Verlag GmbH.

Impact of myeloid-derived suppressor cell on Kupffer cells from mouse livers with hepatocellular carcinoma

PubMed Central

Lacotte, Stéphanie; Slits, Florence; Orci, Lorenzo A.; Meyer, Jeremy; Oldani, Graziano; Gonelle-Gispert, Carmen; Morel, Philippe; Toso, Christian

2016-01-01

ABSTRACT Kupffer cells represent the first line of defense against tumor cells in the liver. Myeloid-derived suppressor cells (MDSC) have recently been observed in the liver parenchyma of tumor-bearing animals. The present study investigates the function of the MDSC subsets, and their impact on Kupffer cell phenotype and function. RIL-175 mouse hepatocellular carcinoma (HCC) cells were injected into the median liver lobe of C57BL/6 mice. Three weeks later, the median lobe hosting the tumor nodule was removed, and Kupffer cells and MDSCs were sorted from the remaining liver. Mouse livers devoid of HCC served as control. Kupffer cells expressed less co-stimulatory CD86 and MHCII and more co-inhibitory CD274 molecules in HCC-bearing livers than in control livers. Corresponding to this phenotype, Kupffer cells from HCC-bearing mice were less efficient in their function as antigen-presenting cells. Three CD11b+ cell populations were identified and sorted from HCC-bearing mice. These cells had various phenotypes with different levels of MDSC-specific surface markers (Ly6Ghigh cells, Gr1high cells, and Ly6Clow cells), and may be considered as bonafide MDSCs given their suppression of antigen-specific T cell proliferation. Primary isolated Kupffer cells in co-culture with the three MDSC subsets showed a decrease in CCL2 and IL-18 secretion, and an increase in IL-10 and IL-1β secretion, and an increased expression of CD86, CD274, and MHCII. In conclusion, these data demonstrated the existence of three MDSC subsets in HCC-bearing animals. These cells altered Kupffer cell function and may decrease the migration and activation of anticancer effector cells in the liver. PMID:27999748

In vivo evidence for unidentified leptin-induced circulating factors that control white fat mass.

PubMed

Harris, Ruth B S

2015-12-15

Fat transplants increase body fat mass without changing the energy status of an animal and provide a tool for investigating control of total body fat. Early transplant studies found that small pieces of transplanted fat took on the morphology of the transplant recipient. Experiments described here tested whether this response was dependent upon expression of leptin receptors in either transplanted fat or the recipient mouse. Fat from leptin receptor deficient db/db mice or wild-type mice was placed subcutaneously in db/db mice. After 12 wk, cell size distribution in the transplant was the same as in endogenous fat of the recipient. Thus, wild-type fat cells, which express leptin receptors, were enlarged in a hyperleptinemic environment, indicating that leptin does not directly control adipocyte size. By contrast, db/db or wild-type fat transplanted into wild-type mice decreased in size, suggesting that a functional leptin system in the recipient is required for body fat mass to be controlled. In the final experiment, wild-type fat was transplanted into a db/db mouse parabiosed to either another db/db mouse to an ob/ob mouse or in control pairs in which both parabionts were ob/ob mice. Transplants increased in size in db/db-db/db pairs, decreased in db/db-ob/ob pairs and did not change in ob/ob-ob/ob pairs. We propose that leptin from db/db parabionts activated leptin receptors in their ob/ob partners. This, in turn, stimulated release of unidentified circulating factors, which travelled back to the db/db partner and acted on the transplant to reduce fat cell size. Copyright © 2015 the American Physiological Society.

Putative signaling action of amelogenin utilizes the Wnt/beta-catenin pathway.

PubMed

Matsuzawa, M; Sheu, T-J; Lee, Y-J; Chen, M; Li, T-F; Huang, C T; Holz, J D; Puzas, J E

2009-06-01

While it has long been known that amelogenin is essential for the proper development of enamel, its role has generally been seen as structural in nature. However, our new data implicate this protein in the regulation of cell signaling pathways in periodontal ligament cells and osteoblasts. In this article we report the successful purification of a recombinant mouse amelogenin protein and demonstrate that it has signaling activity in isolated mouse calvarial cells and human periodontal ligament cells. To determine the regulatory function of canonical Wnt signaling by amelogenin, we used TOPGAL transgenic mice. These mice express a beta-galactosidase transgene under the control of a LEF/TCF and beta-catenin-inducible promoter. To investigate in greater detail the molecular mechanisms involved in the beta-catenin signaling pathway, isolated osteoblasts and periodontal ligament cells were exposed to full-length recombinant mouse amelogenin and were evaluated for phenotypic changes and beta-catenin signaling using a TOPFLASH construct and the LacZ reporter gene. In these in vitro models, we showed that amelogenin can activate beta-catenin signaling. Using the TOPGAL transgenic mouse we showed that amelogenin expression in vivo is localized mainly around the root, the periodontal ligament and the alveolar bone.

Brain oxygen tension controls the expansion of outer subventricular zone-like basal progenitors in the developing mouse brain.

PubMed

Wagenführ, Lisa; Meyer, Anne K; Braunschweig, Lena; Marrone, Lara; Storch, Alexander

2015-09-01

The mammalian neocortex shows a conserved six-layered structure that differs between species in the total number of cortical neurons produced owing to differences in the relative abundance of distinct progenitor populations. Recent studies have identified a new class of proliferative neurogenic cells in the outer subventricular zone (OSVZ) in gyrencephalic species such as primates and ferrets. Lissencephalic brains of mice possess fewer OSVZ-like progenitor cells and these do not constitute a distinct layer. Most in vitro and in vivo studies have shown that oxygen regulates the maintenance, proliferation and differentiation of neural progenitor cells. Here we dissect the effects of fetal brain oxygen tension on neural progenitor cell activity using a novel mouse model that allows oxygen tension to be controlled within the hypoxic microenvironment in the neurogenic niche of the fetal brain in vivo. Indeed, maternal oxygen treatment of 10%, 21% and 75% atmospheric oxygen tension for 48 h translates into robust changes in fetal brain oxygenation. Increased oxygen tension in fetal mouse forebrain in vivo leads to a marked expansion of a distinct proliferative cell population, basal to the SVZ. These cells constitute a novel neurogenic cell layer, similar to the OSVZ, and contribute to corticogenesis by heading for deeper cortical layers as a part of the cortical plate. © 2015. Published by The Company of Biologists Ltd.

Overproduction of S-adenosylmethionine decarboxylase in ethylglyoxal-bis(guanylhydrazone)-resistant mouse FM3A cells.

PubMed

Suzuki, T; Sadakata, Y; Kashiwagi, K; Hoshino, K; Kakinuma, Y; Shirahata, A; Igarashi, K

1993-07-15

A variant cell line, termed SAM-1, which overproduced S-adenosylmethionine decarboxylase (AdoMetDC), was isolated by treatment of mouse FM3A cells with N-methyl-N'-nitro-N-nitrosoguanidine and subsequent incubation with ethylglyoxal bis(guanylhydrazone), an inhibitor of the enzyme. The cells were resistant to ethylglyoxal bis(guanylhydrazone), and showed AdoMetDC activity approximately five-times higher than control cells. The rate of AdoMetDC synthesis and the amount of AdoMetDC existing in SAM-1 cells were about five-times those in control cells. The amount of AdoMetDC mRNA existing in SAM-1 cells was five-times more than that in control cells. The amount of 5'-([(Z)-4-amino-2-butenyl]methylamino)-5'-deoxyadenosine, an irreversible inhibitor of AdoMetDC, necessary to inhibit cell growth was also five-times more in SAM-1 cells than in control cells. However, the following were the same in both SAM-1 and control cells; the amount of genomic DNA for AdoMetDC, the size and nucleotide sequence of 5' untranslated region of AdoMetDC mRNA, the deduced amino acid sequence (334 residues) from the nucleotide sequence of AdoMetDC cDNA and the degradation rate (t1/2 = about 4 h) of AdoMetDC. In addition, AdoMetDC mRNA in control cells was slightly more stable than that in SAM-1 cells. The results indicate that the overproduction of AdoMetDC in SAM-1 cells was caused by the increase of AdoMetDC mRNA. The variant cell line is convenient for studying the regulation of AdoMetDC and the physiological function of polyamines.

Effect of human alpha 2HS glycoprotein on mouse macrophage function.

PubMed Central

Lewis, J G; André, C M

1980-01-01

alpha 2HS glycoprotein was isolated from normal adult serum. The ability of alpha 2HS glycoprotein to promote the endocytosis of radiolabelled DNA and radiolabelled latex particles by mouse macrophages was investigated. The results using both radiolabelled latex particles and radiolabelled DNA show that alpha 2HS glycoprotein enhances the ability of mouse macrophages to take up these radiolabelled substrates as compared to control cells. Images Figure 1 Figure 2 PMID:7439929

Cell-type Specific Optogenetic Mice for Dissecting Neural Circuitry Function

PubMed Central

Zhao, Shengli; Ting, Jonathan T.; Atallah, Hisham E.; Qiu, Li; Tan, Jie; Gloss, Bernd; Augustine, George J.; Deisseroth, Karl; Luo, Minmin; Graybiel, Ann M.; Feng, Guoping

2011-01-01

Optogenetic methods have emerged as powerful tools for dissecting neural circuit connectivity, function, and dysfunction. We used a Bacterial Artificial Chromosome (BAC) transgenic strategy to express Channelrhodopsin2 (ChR2) under the control of cell-type specific promoter elements. We provide a detailed functional characterization of the newly established VGAT-ChR2-EYFP, ChAT-ChR2-EYFP, TPH2-ChR2-EYFP and Pvalb-ChR2-EYFP BAC transgenic mouse lines and demonstrate the utility of these lines for precisely controlling action potential firing of GABAergic, cholinergic, serotonergic, and parvalbumin+ neuron subsets using blue light. This resource of cell type-specific ChR2 mouse lines will facilitate the precise mapping of neuronal connectivity and the dissection of the neural basis of behavior. PMID:21985008

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan, Aping; Research Group of Gastrointestinal Diseases, The Second Affiliated Hospital of Zhengzhou University, Henan; Yang, Hang

Diverse T help (Th) cells play a crucial role in the processing and maintaining of chronic inflammation as seen in ulcerative colitis (UC). Th9, a novel subset of Th cells that primarily produces interleukin (IL)-9, has recently been associated with the development of inflammatory diseases. In this study, we evaluated the presentation of Th9 cells in inflamed tissues of human and experimental mouse UC, and examined the therapeutic efficiency of anti Th9 cytokine IL-9 in the experimental mouse UC. Using immunohistochemistry (IHC), we evaluated the presentation of Th9 cells labelled by transcriptional factor PU.1 in both human and dextran sulfatemore » sodium (DSS) induced mouse colitis biopsies. The results showed that increased PU.1 positive Th9 cells were mainly located in the lamina propria in relative with the controls, intraepithelial Th9 cells can also be observed but at low density. Double IHCs revealed that most of PU.1 positive cells were CD3 positive lymphocytes in human UC specimens. Anti-IL-9 antibody injection for 2 weeks reduced the severity of inflammation in DSS induced colitis mice. Our results suggest that The Th9/IL-9 is involved in the pathogenesis of UC. - Highlights: • The density of novel PU.1 positive Th9 cells is significantly increased in both human and mouse colitis tissues. • PU.1 positive Th9 cells are predominately located in the inflamed lamina propria in both human and mouse colitis tissues. • Blocking of Th9 cytokine IL-9 by antibody injection suppresses the severity of inflammation in the bowel in colitis mice. • Novel Th9 cells contribute to the pathogenesis of UC.« less

Generation of tooth-periodontium complex structures using high-odontogenic potential dental epithelium derived from mouse embryonic stem cells.

PubMed

Zhang, Yancong; Li, Yongliang; Shi, Ruirui; Zhang, Siqi; Liu, Hao; Zheng, Yunfei; Li, Yan; Cai, Jinglei; Pei, Duanqing; Wei, Shicheng

2017-06-08

A number of studies have shown that tooth-like structures can be regenerated using induced pluripotent stem cells and mouse embryonic stem (mES) cells. However, few studies have reported the regeneration of tooth-periodontium complex structures, which are more suitable for clinical tooth transplantation. We established an optimized approach to induce high-odontogenic potential dental epithelium derived from mES cells by temporally controlling bone morphogenic protein 4 (BMP4) function and regenerated tooth-periodontium complex structures in vivo. First, immunofluorescence and quantitative reverse transcription-polymerase chain reaction were used to identify the watershed of skin and the oral ectoderm. LDN193189 was then used to inhibit the BMP4 receptor around the watershed, followed by the addition of exogenous BMP4 to promote BMP4 function. The generated dental epithelium was confirmed by western blot analysis and immunofluorescence. The generated epithelium was ultimately combined with embryonic day 14.5 mouse mesenchyme and transplanted into the renal capsules of nude mice. After 4 weeks, the tooth-periodontium complex structure was examined by micro-computed tomography (CT) and hematoxylin and eosin (H&E) staining. Our study found that the turning point of oral ectoderm differentiation occurred around day 3 after the embryoid body was transferred to a common culture plate. Ameloblastin-positive dental epithelial cells were detected following the temporal regulation of BMP4. Tooth-periodontium complex structures, which included teeth, a periodontal membrane, and alveolar bone, were formed when this epithelium was combined with mouse dental mesenchyme and transplanted into the renal capsules of nude mice. Micro-CT and H&E staining revealed that the generated tooth-periodontium complex structures shared a similar histological structure with normal mouse teeth. An optimized induction method was established to promote the differentiation of mES cells into dental epithelium by temporally controlling the function of BMP4. A novel tooth-periodontium complex structure was generated using the epithelium.

The maintenance of pluripotency following laser direct-write of mouse embryonic stem cells.

PubMed

Raof, Nurazhani Abdul; Schiele, Nathan R; Xie, Yubing; Chrisey, Douglas B; Corr, David T

2011-03-01

The ability to precisely pattern embryonic stem (ES) cells in vitro into predefined arrays/geometries may allow for the recreation of a stem cell niche for better understanding of how cellular microenvironmental factors govern stem cell maintenance and differentiation. In this study, a new gelatin-based laser direct-write (LDW) technique was utilized to deposit mouse ES cells into defined arrays of spots, while maintaining stem cell pluripotency. Results obtained from these studies showed that ES cells were successfully printed into specific patterns and remained viable. Furthermore, ES cells retained the expression of Oct4 in nuclei after LDW, indicating that the laser energy did not affect their maintenance of an undifferentiated state. The differentiation potential of mouse ES cells after LDW was confirmed by their ability to form embryoid bodies (EBs) and to spontaneously become cell lineages representing all three germ layers, revealed by the expression of marker proteins of nestin (ectoderm), Myf-5 (mesoderm) and PDX-1 (endoderm), after 7 days of cultivation. Gelatin-based LDW provides a new avenue for stem cell patterning, with precision and control of the cellular microenvironment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Knockdown of p53 suppresses Nanog expression in embryonic stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdelalim, Essam Mohamed, E-mail: emohamed@qf.org.qa; Molecular Neuroscience Research Center, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192; Department of Cytology and Histology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia

2014-01-10

Highlights: •We investigate the role of p53 in ESCs in the absence of DNA damage. •p53 knockdown suppresses ESC proliferation. •p53 knockdown downregulates Nanog expression. •p53 is essential for mouse ESC self-renewal. -- Abstract: Mouse embryonic stem cells (ESCs) express high levels of cytoplasmic p53. Exposure of mouse ESCs to DNA damage leads to activation of p53, inducing Nanog suppression. In contrast to earlier studies, we recently reported that chemical inhibition of p53 suppresses ESC proliferation. Here, we confirm that p53 signaling is involved in the maintenance of mouse ESC self-renewal. RNA interference-mediated knockdown of p53 induced downregulation of p21more » and defects in ESC proliferation. Furthermore, p53 knockdown resulted in a significant downregulation in Nanog expression at 24 and 48 h post-transfection. p53 knockdown also caused a reduction in Oct4 expression at 48 h post-transfection. Conversely, exposure of ESCs to DNA damage caused a higher reduction of Nanog expression in control siRNA-treated cells than in p53 siRNA-treated cells. These data show that in the absence of DNA damage, p53 is required for the maintenance of mouse ESC self-renewal by regulating Nanog expression.« less

Nuclear p120-catenin regulates the anoikis resistance of mouse lobular breast cancer cells through Kaiso-dependent Wnt11 expression

PubMed Central

van de Ven, Robert A. H.; Tenhagen, Milou; Meuleman, Wouter; van Riel, Jeske J. G.; Schackmann, Ron C. J.; Derksen, Patrick W. B.

2015-01-01

E-cadherin inactivation underpins the progression of invasive lobular breast carcinoma (ILC). In ILC, p120-catenin (p120) translocates to the cytosol where it controls anchorage independence through the Rho-Rock signaling pathway, a key mechanism driving tumor growth and metastasis. We now demonstrate that anchorage-independent ILC cells show an increase in nuclear p120, which results in relief of transcriptional repression by Kaiso. To identify the Kaiso target genes that control anchorage independence we performed genome-wide mRNA profiling on anoikis-resistant mouse ILC cells, and identified 29 candidate target genes, including the established Kaiso target Wnt11. Our data indicate that anchorage-independent upregulation of Wnt11 in ILC cells is controlled by nuclear p120 through inhibition of Kaiso-mediated transcriptional repression. Finally, we show that Wnt11 promotes activation of RhoA, which causes ILC anoikis resistance. Our findings thereby establish a mechanistic link between E-cadherin loss and subsequent control of Rho-driven anoikis resistance through p120- and Kaiso-dependent expression of Wnt11. PMID:25713299

Automatic Stem Cell Detection in Microscopic Whole Mouse Cryo-imaging

PubMed Central

Wuttisarnwattana, Patiwet; Gargesha, Madhusudhana; Hof, Wouter van’t; Cooke, Kenneth R.

2016-01-01

With its single cell sensitivity over volumes as large as or larger than a mouse, cryo-imaging enables imaging of stem cell biodistribution, homing, engraftment, and molecular mechanisms. We developed and evaluated a highly automated software tool to detect fluorescently labeled stem cells within very large (~200GB) cryo-imaging datasets. Cell detection steps are: preprocess, remove immaterial regions, spatially filter to create features, identify candidate pixels, classify pixels using bagging decision trees, segment cell patches, and perform 3D labeling. There are options for analysis and visualization. To train the classifier, we created synthetic images by placing realistic digital cell models onto cryo-images of control mice devoid of cells. Very good cell detection results were (precision=98.49%, recall=99.97%) for synthetic cryo-images, (precision=97.81%, recall=97.71%) for manually evaluated, actual cryo-images, and <1% false positives in control mice. An α-multiplier applied to features allows one to correct for experimental variations in cell brightness due to labeling. On dim cells (37% of standard brightness), with correction, we improved recall (49.26%→99.36%) without a significant drop in precision (99.99%→99.75%). With tail vein injection, multipotent adult progenitor cells in a graft-versus-host-disease model in the first days post injection were predominantly found in lung, liver, spleen, and bone marrow. Distribution was not simply related to blood flow. The lung contained clusters of cells while other tissues contained single cells. Our methods provided stem cell distribution anywhere in mouse with single cell sensitivity. Methods should provide a rational means of evaluating dosing, delivery methods, cell enhancements, and mechanisms for therapeutic cells. PMID:26552080

Endocochlear potential generation is associated with intercellular communication in the stria vascularis: structural analysis in the viable dominant spotting mouse mutant.

PubMed

Carlisle, L; Steel, K; Forge, A

1990-11-01

Deafness in the viable dominant spotting mouse mutant is due to a primary defect of the stria vascularis which results in absence of the positive endocochlear potential in scala media. Endocochlear potentials were measured and the structure of stria vascularis of mutants with potentials close to zero was compared with that in normal littermate controls by use of morphometric methods. The stria vascularis was significantly thinner in mutants. Marginal cells were not significantly different from controls in terms of volume density or intramembrane particle density but the network density of tight junctions was significantly reduced in the mutants. A virtual absence of gap junctions between basal cells and marginal or intermediate cells was observed, but intramembrane particle density and junctional complexes between adjacent basal cells were not different from controls. The volume density of basal cells was significantly greater in mutants. Intermediate cells accounted for a significantly smaller volume density of the stria vascularis in mutants and had a lower density of intramembrane particles than controls. Melanocytes were not identified in the stria vascularis of mutants. These results suggest that communication between marginal, intermediate and basal cells might be important to the normal function of the stria vascularis.

Ibrutinib suppresses alloantibody responses in a mouse model of allosensitization.

PubMed

Kim, Irene; Wu, Gordon; Chai, Ning-Ning; Klein, Andrew S; Jordan, Stanley

2017-12-01

Ibrutinib is a Bruton's tyrosine Kinase (BTK) antagonist that inhibits B cell receptor (BCR) signaling. Complete BTK deficiency is associated with absence of B-cells. Ibrutinb is currently approved by FDA for treatment of B-cell malignancies, including Waldenström macroglobulinaemia. We recently carried out studies to determine if ibrutinib could modify alloantibody responses. A mouse model of allogenic sensitization using a C57BL/6 mouse as the recipient of a skin allograft from an HLA-A2 transgenic mouse was utilized to examine the effects of ibrutinib on alloantibody responses and B cell effector functions. Donor-specific antibody (DSA) levels were measured in a flow-cytometric antibody binding assay. Splenic T and B cell subsets and plasma cells were analyzed in flow cytometry. Control mice developed peak levels of DSA IgM at day 14 PTx while the ibrutinib treated mice had significantly lower levels of DSA IgM (p=0.0047). Control mice developed HLA.A2-specific IgG antibodies at day 14 (230±60 MFI) and reached peak levels at day 21 (426±61 MFI). In contrast, mice in the treatment group had low levels of HLA.A2-specific IgG at day 14 (109±59 MFI, p=0.004) and day 21 (241±86 MFI, p=0.003). FACS analysis found a reduction of B220 + or CD19 + B cell population (p<0.05). In addition, ibrutinib attenuated recall DSA IgG responses to re-sensitization (p<0.05) and reduced CD38 + CD138 + plasma cells (p<0.05) in the spleens. Ibrutinib is effective in suppressing alloantibody responses through blocking BTK-mediated BCR signaling, leading to reduction of B cells and short-lived plasma cells in the spleens. Use of ibrutinib may provide benefits to HLA-sensitized transplant patients for alloantibody suppression. Copyright © 2017 Elsevier B.V. All rights reserved.

Tungsten carbide-cobalt as a nanoparticulate reference positive control in in vitro genotoxicity assays.

PubMed

Moche, Hélène; Chevalier, Dany; Barois, Nicolas; Lorge, Elisabeth; Claude, Nancy; Nesslany, Fabrice

2014-01-01

With the increasing human exposure to nanoparticles (NP), the evaluation of their genotoxic potential is of significant importance. However, relevance for NP of the routinely used in vitro genotoxicity assays is often questioned, and a nanoparticulate reference positive control would therefore constitute an important step to a better testing of NP, ensuring that test systems are really appropriate. In this study, we investigated the possibility of using tungsten carbide-cobalt (WC-Co) NP as reference positive control in in vitro genotoxicity assays, including 2 regulatory assays, the mouse lymphoma assay and the micronucleus assay, and in the Comet assay, recommended for the toxicological evaluation of nanomedicines by the French Agency of Human Health Products (Afssaps). Through these assays, we were able to study different genetic endpoints in 2 cell types commonly used in regulatory genotoxicity assays: the L5178Y mouse lymphoma cell line and primary cultures of human lymphocytes. Our results showed that the use of WC-Co NP as positive control in in vitro genotoxicity assays was conceivable, but that different parameters have to be considered, such as cell type and treatment schedule. L5178Y mouse lymphoma cells did not provide satisfactory results in the 3 performed tests. However, human lymphocytes were more sensitive to genotoxic effects induced by WC-Co NP, particularly after a 24-h treatment in the in vitro micronucleus assay and after a 4-h treatment in the in vitro Comet assay. Under such conditions, WC-Co could be used as a nanoparticulate reference positive control in these assays.

[Effect of cadmium chloride on immigration of mouse neural stem cell].

PubMed

Zhang, Yuyuan; Wang, Qunan; Chai, Xiaoyu; Shen, Zhongzhou; Gao, Liuwei

2015-01-01

To investigate the effects of cadmium chloride on cytoactive and immigration of mouse neural stem cell (mNSC). MTT assay was used to detect cytoactive at 24 hours. The immigration of mNSC was determined by immunofluorescence staining. Compared with control, CdCl2 treatment at 10.0 μmol/L for 24 h resulted in a decrease in cellular viability (70.08 ± 6.21)% (P < 0.05). Compared with control, Aa/Ab and Dm/Db display decreasing tendency in a dose-dependent manner (r(s Aa/Ab) = - 0.90, γ(s Dm/Db) = - 0.90, P < 0.05) after CdCl2 treatment at 0.1 - 10.0 μmol/L for 24 h. Cadmium chloride treatment inhibits immigration of mNSC, and shows negative effect on cell viability. Meanwhile, the effect of cadmium chloride on immigration is more obvious than cell viability at the same concentration for same treatment time.

Embryotrophic factor-3 from human oviductal cells affects the messenger RNA expression of mouse blastocyst.

PubMed

Lee, Y L; Lee, K F; Xu, J S; Kwok, K L; Luk, J M; Lee, W M; Yeung, W S B

2003-02-01

Our previous results showed that embryotrophic factor-3 (ETF-3) from human oviductal cells increased the size and hatching rate of mouse blastocysts in vitro. The present study investigated the production of ETF-3 by an immortalized human oviductal cell line (OE-E6/E7) and the effects of ETF-3 on the mRNA expression of mouse embryos. The ETF-3 was purified from primary oviductal cell conditioned media using sequential liquid chromatographic systems, and antiserum against ETF-3 was raised. The ETF-3-supplemented Chatot-Ziomek-Bavister medium was used to culture Day 1 MF1 x BALB/c mouse embryos for 4 days. The ETF-3 treatment significantly enhanced the mouse embryo blastulation and hatching rate. The antiserum, at concentrations of 0.03-3%, abolished the embryotrophic effect of ETF-3. Positive ETF-3 immunoreactivity was detected in the primary oviductal cells, OE-E6/E7, and blastocysts derived from ETF-3 treatment. Vero cells (African Green Monkey kidney cell line), fibroblasts, and embryos cultured in control medium did not possess ETF-3 immunoreactivity. The mRNA expression patterns of the treated embryos were studied at the blastocyst stage by mRNA differential display reverse transcription-polymerase chain reaction (DDRT-PCR). The DDRT-PCR showed that some of the mRNAs were differentially expressed after ETF-3 treatment. Twelve of the differentially expressed mRNAs that had high homology with cDNA sequences in the GenBank were selected for further characterization. The differential expression of seven of these mRNAs (ezrin, heat shock 70-kDa protein, cytochrome c oxidase subunit VIIa-L precursor, proteinase-activated receptor 2, eukaryotic translation initiation factor 2beta, cullin 1, and proliferating cell nuclear antigen) was confirmed by semiquantitative RT-PCR. In conclusion, immortalized oviductal cells produce ETF-3, which influences mRNA expression of mouse blastocyst.

Constitutive expression of tert in thymocytes leads to increased incidence and dissemination of T-cell lymphoma in Lck-Tert mice.

PubMed

Canela, Andrés; Martín-Caballero, Juan; Flores, Juana M; Blasco, María A

2004-05-01

Here we describe a new mouse model with constitutive expression of the catalytic subunit of telomerase (Tert) targeted to thymocytes and peripheral T cells (Lck-Tert mice). Two independent Lck-Tert mouse lines showed higher incidences of spontaneous T-cell lymphoma than the corresponding age-matched wild-type controls, indicating that constitutive expression of Tert promotes lymphoma. Interestingly, T-cell lymphomas in Lck-Tert mice were more disseminated than those in wild-type controls and affected both lymphoid and nonlymphoid tissues, while nonlymphoid tissues were never affected with lymphoma in age-matched wild-type controls. Importantly, these roles of Tert constitutive expression in promoting tumor progression and dissemination were independent of the role of telomerase in telomere length maintenance, since telomere length distributions on a single-cell basis were identical in Lck-Tert and wild-type thymocytes. Finally, Tert constitutive expression did not interfere with telomere capping in Lck-Tert primary thymocytes, although it resulted in greater chromosomal instability upon gamma irradiation in Lck-Tert primary lymphocytes than in controls, suggesting that Tert overexpression may interfere with the cellular response to DNA damage.

The stem cell growth factor receptor KIT is not expressed on interstitial cells in bladder.

PubMed

Gevaert, Thomas; Ridder, Dirk De; Vanstreels, Els; Daelemans, Dirk; Everaerts, Wouter; Aa, Frank Van Der; Pintelon, Isabel; Timmermans, Jean-Pierre; Roskams, Tania; Steiner, Clara; Neuhaus, Jochen

2017-06-01

The mast/stem cell growth factor receptor KIT has long been assumed to be a specific marker for interstitial cells of Cajal (ICC) in the bladder, with possible druggable perspectives. However, several authors have challenged the presence of KIT + ICC in recent years. The aim of this study was therefore to attempt to clarify the conflicting reports on KIT expression in the bladder of human beings, rat, mouse and guinea pig and to elucidate the possible role of antibody-related issues and interspecies differences in this matter. Fresh samples were obtained from human, rat, mouse and guinea pig cystectomies and processed for single/double immunohistochemistry/immunofluorescence. Specific antibodies against KIT, mast cell tryptase (MCT), anoctamin-1 (ANO1) and vimentin were used to characterize the cell types expressing KIT. Gut (jejunum) tissue was used as an external antibody control. Our results revealed KIT expression on mast cells but not on ICC in human, rat, mouse and guinea pig bladder. Parallel immunohistochemistry showed KIT expression on ICC in human, rat, mouse and guinea pig gut, which confirmed the selectivity of the KIT antibody clones. In conclusion, we have shown that KIT + cells in human, rat, mouse and guinea pig bladder are mast cells and not ICC. The present report is important as it opposes the idea that KIT + ICC are present in bladder. In this perspective, functional concepts of KIT + ICC being involved in sensory and/or motor aspects of bladder physiology should be revised. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Can we induce spermatogenesis in the domestic cat using an in vitro tissue culture approach?

PubMed Central

Amaral, Sandra; Tavares, Renata S.; Schlatt, Stefan; Ramalho-Santos, João

2018-01-01

The reduced number of animals in most wild felid populations implies a loss of genetic diversity. The death of juveniles, prior to the production of mature sperm, represents a loss of potential genetic contribution to future populations. Since 2011 mouse testicular organ culture has introduced an alternative mechanism to produce sperm in vitro from immature tissue. However, extension of this technology to other species has remained limited. We have used the domestic cat (Felis catus) as a model for wild felids to investigate spermatogenesis initiation and regulation, with the mouse serving as a control species. Testicular tissue fragments were cultured in control medium or medium supplemented with knockout serum replacement (KSR), AlbuMax, beta-estradiol or AlbuMax plus beta-estradiol. Contrary to expectations, and unlike results obtained in mouse controls, no germ cell differentiation could be detected. The only germ cells observed after six weeks of culture were spermatogonia regardless of the initial stage of tubule development in the donor tissue. Moreover, the number of spermatogonia decreased with time in culture in all media tested, especially in the medium supplemented with KSR, while AlbuMax had a slight protective effect. The combination of AlbuMax and beta-estradiol led to an increase in the area occupied by seminiferous tubules, and thus to an increase in total number of spermatogonial cells. Considering all the media combinations tested the stimulus for felid germ cell differentiation in this type of system seems to be different from the mouse. Studies using other triggers of differentiation and tissue survival factors should be performed to pursue this technology for the genetic diversity preservation in wild felids. PMID:29414992

Phenotypic outcomes in Mouse and Human Foxc1 dependent Dandy-Walker cerebellar malformation suggest shared mechanisms.

PubMed

Haldipur, Parthiv; Dang, Derek; Aldinger, Kimberly A; Janson, Olivia K; Guimiot, Fabien; Adle-Biasette, Homa; Dobyns, William B; Siebert, Joseph R; Russo, Rosa; Millen, Kathleen J

2017-01-16

FOXC1 loss contributes to Dandy-Walker malformation (DWM), a common human cerebellar malformation. Previously, we found that complete Foxc1 loss leads to aberrations in proliferation, neuronal differentiation and migration in the embryonic mouse cerebellum (Haldipur et al., 2014). We now demonstrate that hypomorphic Foxc1 mutant mice have granule and Purkinje cell abnormalities causing subsequent disruptions in postnatal cerebellar foliation and lamination. Particularly striking is the presence of a partially formed posterior lobule which echoes the posterior vermis DW 'tail sign' observed in human imaging studies. Lineage tracing experiments in Foxc1 mutant mouse cerebella indicate that aberrant migration of granule cell progenitors destined to form the posterior-most lobule causes this unique phenotype. Analyses of rare human del chr 6p25 fetal cerebella demonstrate extensive phenotypic overlap with our Foxc1 mutant mouse models, validating our DWM models and demonstrating that many key mechanisms controlling cerebellar development are likely conserved between mouse and human.

Anti-tumor activity of high-dose EGFR tyrosine kinase inhibitor and sequential docetaxel in wild type EGFR non-small cell lung cancer cell nude mouse xenografts

PubMed Central

Tang, Ning; Zhang, Qianqian; Fang, Shu; Han, Xiao; Wang, Zhehai

2017-01-01

Treatment of non-small-cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR) is still a challenge. This study explored antitumor activity of high-dose icotinib (an EGFR tyrosine kinase inhibitor) plus sequential docetaxel against wild-type EGFR NSCLC cells-generated nude mouse xenografts. Nude mice were subcutaneously injected with wild-type EGFR NSCLC A549 cells and divided into different groups for 3-week treatment. Tumor xenograft volumes were monitored and recorded, and at the end of experiments, tumor xenografts were removed for Western blot and immunohistochemical analyses. Compared to control groups (negative control, regular-dose icotinib [IcoR], high-dose icotinib [IcoH], and docetaxel [DTX]) and regular icotinib dose (60 mg/kg) with docetaxel, treatment of mice with a high-dose (1200 mg/kg) of icotinib plus sequential docetaxel for 3 weeks (IcoH-DTX) had an additive effect on suppression of tumor xenograft size and volume (P < 0.05). Icotinib-containing treatments markedly reduced phosphorylation of EGFR, mitogen activated protein kinase (MAPK), and protein kinase B (Akt), but only the high-dose icotinib-containing treatments showed an additive effect on CD34 inhibition (P < 0.05), an indication of reduced microvessel density in tumor xenografts. Moreover, high-dose icotinib plus docetaxel had a similar effect on mouse weight loss (a common way to measure adverse reactions in mice), compared to the other treatment combinations. The study indicate that the high dose of icotinib plus sequential docetaxel (IcoH-DTX) have an additive effect on suppressing the growth of wild-type EGFR NSCLC cell nude mouse xenografts, possibly through microvessel density reduction. Future clinical trials are needed to confirm the findings of this study. PMID:27852073

SiRNA-Mediated Down-Regulation of CLIC4 Gene Inhibits Cell Proliferation and Accelerates Cell Apoptosis of Mouse Liver Cancer Hca-F and Hca-P Cells.

PubMed

Yu, Qiu-Yun; Zhou, Xin-Feng; Xia, Qing; Shen, Jia; Yan, Jia; Zhu, Jiu-Ting; Li, Xiang; Shu, Ming

2018-01-01

This study explored the effects involved in silencing CLIC4 on apoptosis and proliferation of mouse liver cancer Hca-F and Hca-P cells. A CLIC4-target small interfering RNA (siRNA) was designed to compound into two individual complementary oligonucleotide chains. A process of annealing and connection to a pSilencer vector was followed by transfection with Hca-F and Hca-P cells. Quantitative real-time polymerase chain reaction and Western blotting techniques were used to determine CLIC4 mRNA and protein expressions. CCK8 assay and flow cytometry were employed for analysis of the survival and apoptosis rate as well as the cell cycle in an octreotide-induced apoptosis model. Expressions of caspase 3, caspase 9, and cleaved PARP were measured using Western blotting. The CLIC4 mRNA and protein expressions in Hca-F and Hca-P cells transfected by pSilencer-CLIC4 siRNA plasmid in the blank group displayed remarkably decreased levels of expression, when compared with both the control and negative control (NC) groups. Decreased survival rates and cleaved PARP expression, increased cell apoptosis rate,expressions of caspase 3 and caspase 9 in Hca-F and Hca-P cells were detected in groups that had been cultured in a medium containing octreotide. The pSilencer-CLIC4 siRNA-2 group when compared with the control and NC groups exhibited decreased survival rates, cleaved PARP expression, increased cell apoptosis rates, and increased expressions of caspase 3 and caspase 9 of Hca-F and Hca-P cells. The results demonstrated that siRNA-induced down-regulation of CLIC4 could proliferation, while in turn promoting apoptosis of mouse liver cancer Hca-F and Hca-P cells. J. Cell. Biochem. 119: 659-668, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Systematic variation in mRNA 3′-processing signals during mouse spermatogenesis

PubMed Central

Liu, Donglin; Brockman, J. Michael; Dass, Brinda; Hutchins, Lucie N.; Singh, Priyam; McCarrey, John R.; MacDonald, Clinton C.; Graber, Joel H.

2007-01-01

Gene expression and processing during mouse male germ cell maturation (spermatogenesis) is highly specialized. Previous reports have suggested that there is a high incidence of alternative 3′-processing in male germ cell mRNAs, including reduced usage of the canonical polyadenylation signal, AAUAAA. We used EST libraries generated from mouse testicular cells to identify 3′-processing sites used at various stages of spermatogenesis (spermatogonia, spermatocytes and round spermatids) and testicular somatic Sertoli cells. We assessed differences in 3′-processing characteristics in the testicular samples, compared to control sets of widely used 3′-processing sites. Using a new method for comparison of degenerate regulatory elements between sequence samples, we identified significant changes in the use of putative 3′-processing regulatory sequence elements in all spermatogenic cell types. In addition, we observed a trend towards truncated 3′-untranslated regions (3′-UTRs), with the most significant differences apparent in round spermatids. In contrast, Sertoli cells displayed a much smaller trend towards 3′-UTR truncation and no significant difference in 3′-processing regulatory sequences. Finally, we identified a number of genes encoding mRNAs that were specifically subject to alternative 3′-processing during meiosis and postmeiotic development. Our results highlight developmental differences in polyadenylation site choice and in the elements that likely control them during spermatogenesis. PMID:17158511

Microgravity inhibition of lipopolysaccharide-induced tumor necrosis factor-α expression in macrophage cells.

PubMed

Wang, Chongzhen; Luo, Haiying; Zhu, Linnan; Yang, Fan; Chu, Zhulang; Tian, Hongling; Feng, Meifu; Zhao, Yong; Shang, Peng

2014-01-01

Microgravity environments in space can cause major abnormalities in human physiology, including decreased immunity. The underlying mechanisms of microgravity-induced inflammatory defects in macrophages are unclear. RAW264.7 cells and primary mouse macrophages were used in the present study. Lipopolysaccharide (LPS)-induced cytokine expression in mouse macrophages was detected under either simulated microgravity or 1g control. Freshly isolated primary mouse macrophages and RAW264.7 cells were cultured in a standard simulated microgravity situation using a rotary cell culture system (RCCS-1) and 1g control conditions. The cytokine expression was determined by real-time PCR and ELISA assays. Western blots were used to investigate the related intracellular signals. LPS-induced tumor necrosis factor-α (TNF-α) expression, but not interleukin-1β expression, in mouse macrophages was significantly suppressed under simulated microgravity. The molecular mechanism studies showed that LPS-induced intracellular signal transduction including phosphorylation of IKK and JNK and nuclear translocation of NF-κB in macrophages was identical under normal gravity and simulated microgravity. Furthermore, TNF-α mRNA stability did not decrease under simulated microgravity. Finally, we found that heat shock factor-1 (HSF1), a known repressor of TNF-α promoter, was markedly activated under simulated microgravity. Short-term treatment with microgravity caused significantly decreased TNF-α production. Microgravity-activated HSF1 may contribute to the decreased TNF-α expression in macrophages directly caused by microgravity, while the LPS-induced NF-κB pathway is resistant to microgravity.

Regional Fluctuation in the Functional Consequence of LINE-1 Insertion in the Mitf Gene: The Black Spotting Phenotype Arisen from the Mitfmi-bw Mouse Lacking Melanocytes

PubMed Central

Yamamoto, Hiroaki; Shibahara, Shigeki

2016-01-01

Microphthalmia-associated transcription factor (Mitf) is a key regulator for differentiation of melanoblasts, precursors to melanocytes. The mouse homozygous for the black-eyed white (Mitfmi-bw) allele is characterized by the white-coat color and deafness with black eyes due to the lack of melanocytes. The Mitfmi-bw allele carries LINE-1, a retrotransposable element, which results in the Mitf deficiency. Here, we have established the black spotting mouse that was spontaneously arisen from the homozygous Mitfmi-bw mouse lacking melanocytes. The black spotting mouse shows multiple black patches on the white coat, with age-related graying. Importantly, each black patch also contains hair follicles lacking melanocytes, whereas the white-coat area completely lacks melanocytes. RT-PCR analyses of the pigmented patches confirmed that the LINE-1 insertion is retained in the Mitf gene of the black spotting mouse, thereby excluding the possibility of the somatic reversion of the Mitfmi-bw allele. The immunohistochemical analysis revealed that the staining intensity for beta-catenin was noticeably lower in hair follicles lacking melanocytes of the homozygous Mitfmi-bw mouse and the black spotting mouse, compared to the control mouse. In contrast, the staining intensity for beta-catenin and cyclin D1 was higher in keratinocytes of the black spotting mouse, compared to keratinocytes of the control mouse and the Mitfmi-bw mouse. Moreover, the keratinocyte layer appears thicker in the Mitfmi-bw mouse, with the overexpression of Ki-67, a marker for cell proliferation. We also show that the presumptive black spots are formed by embryonic day 15.5. Thus, the black spotting mouse provides the unique model to explore the molecular basis for the survival and death of developing melanoblasts and melanocyte stem cells in the epidermis. These results indicate that follicular melanocytes are responsible for maintaining the epidermal homeostasis; namely, the present study has provided evidence for the link between melanocyte development and the epidermal microenvironment. PMID:26930598

The miR-29b-Sirt1 axis regulates self-renewal of mouse embryonic stem cells in response to reactive oxygen species.

PubMed

Xu, Zengguang; Zhang, Lei; Fei, Xuejie; Yi, Xiuwen; Li, Wenxian; Wang, Qingxiu

2014-07-01

Endogenous reactive oxygen species (ROS) control is important for the maintenance of self-renewal of embryonic stem (ES) cells. Although miRNAs have been found to be critically involved in the regulation of the self-renewal, whether miRNAs can regulate the signaling axis to control ROS in ES cells is unclear. Here we show that miR-29b specifically regulates the self-renewal of mouse ES cells in response to ROS generated by antioxidant-free culture. Sirt1 is the direct target of miR-29b and can also make mES cells sensitive to ROS and regulate the self-renewal of mES cells during the response of ROS. We further found that Sirt1 could attenuate the miR-29b function in regulating mES cells' self-renewal in response to ROS. Our results determined that miR-29b-Sirt1 axis regulates self-renewal of mES cells in response to ROS. Copyright © 2014 Elsevier Inc. All rights reserved.

An efficient method for generation of bi-allelic null mutant mouse embryonic stem cells and its application for investigating epigenetic modifiers.

PubMed

Fisher, Cynthia L; Marks, Hendrik; Cho, Lily Ting-Yin; Andrews, Robert; Wormald, Sam; Carroll, Thomas; Iyer, Vivek; Tate, Peri; Rosen, Barry; Stunnenberg, Hendrik G; Fisher, Amanda G; Skarnes, William C

2017-12-01

Mouse embryonic stem (ES) cells are a popular model system to study biological processes, though uncovering recessive phenotypes requires inactivating both alleles. Building upon resources from the International Knockout Mouse Consortium (IKMC), we developed a targeting vector for second allele inactivation in conditional-ready IKMC 'knockout-first' ES cell lines. We applied our technology to several epigenetic regulators, recovering bi-allelic targeted clones with a high efficiency of 60% and used Flp recombinase to restore expression in two null cell lines to demonstrate how our system confirms causality through mutant phenotype reversion. We designed our strategy to select against re-targeting the 'knockout-first' allele and identify essential genes in ES cells, including the histone methyltransferase Setdb1. For confirmation, we exploited the flexibility of our system, enabling tamoxifen inducible conditional gene ablation while controlling for genetic background and tamoxifen effects. Setdb1 ablated ES cells exhibit severe growth inhibition, which is not rescued by exogenous Nanog expression or culturing in naive pluripotency '2i' media, suggesting that the self-renewal defect is mediated through pluripotency network independent pathways. Our strategy to generate null mutant mouse ES cells is applicable to thousands of genes and repurposes existing IKMC Intermediate Vectors. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

mTORC1 is essential for leukemia propagation but not stem cell self-renewal

PubMed Central

Hoshii, Takayuki; Tadokoro, Yuko; Naka, Kazuhito; Ooshio, Takako; Muraguchi, Teruyuki; Sugiyama, Naoyuki; Soga, Tomoyoshi; Araki, Kimi; Yamamura, Ken-ichi; Hirao, Atsushi

2012-01-01

Although dysregulation of mTOR complex 1 (mTORC1) promotes leukemogenesis, how mTORC1 affects established leukemia is unclear. We investigated the role of mTORC1 in mouse hematopoiesis using a mouse model of conditional deletion of Raptor, an essential component of mTORC1. Raptor deficiency impaired granulocyte and B cell development but did not alter survival or proliferation of hematopoietic progenitor cells. In a mouse model of acute myeloid leukemia (AML), Raptor deficiency significantly suppressed leukemia progression by causing apoptosis of differentiated, but not undifferentiated, leukemia cells. mTORC1 did not control cell cycle or cell growth in undifferentiated AML cells in vivo. Transplantation of Raptor-deficient undifferentiated AML cells in a limiting dilution revealed that mTORC1 is essential for leukemia initiation. Strikingly, a subset of AML cells with undifferentiated phenotypes survived long-term in the absence of mTORC1 activity. We further demonstrated that the reactivation of mTORC1 in those cells restored their leukemia-initiating capacity. Thus, AML cells lacking mTORC1 activity can self-renew as AML stem cells. Our findings provide mechanistic insight into how residual tumor cells circumvent anticancer therapies and drive tumor recurrence. PMID:22622041

Physically disconnected non-diffusible cell-to-cell communication between neuroblastoma SH-SY5Y and DRG primary sensory neurons.

PubMed

Chaban, Victor V; Cho, Taehoon; Reid, Christopher B; Norris, Keith C

2013-01-01

Cell-cell communication occurs via a variety of mechanisms, including long distances (hormonal), short distances (paracrine and synaptic) or direct coupling via gap junctions, antigen presentation, or ligand-receptor interactions. We evaluated the possibility of neuro-hormonal independent, non-diffusible, physically disconnected pathways for cell-cell communication using dorsal root ganglion (DRG) neurons. We assessed intracellular calcium ([Ca(2+)]) in primary culture DRG neurons that express ATP-sensitive P2X3, capsaicinsensitive TRPV1 receptors modulated by estradiol. Physically disconnected (dish-in-dish system; inner chamber enclosed) mouse DRG were cultured for 12 hours near: a) media alone (control 1), b) mouse DRG (control 2), c) human neuroblastoma SHSY-5Y cells (cancer intervention), or d) mouse DRG treated with KCl (apoptosis intervention). Chemosensitive receptors [Ca(2+)](i) signaling did not differ between control 1 and 2. ATP (10 μM) and capsaicin (100nM) increased [Ca(2+)](i) transients to 425.86 + 49.5 nM, and 399.21 ± 44.5 nM, respectively. 17β-estradiol (100 nM) exposure reduced ATP (171.17 ± 48.9 nM) and capsaicin (175.01±34.8 nM) [Ca(2+)](i) transients. The presence of cancer cells reduced ATP- and capsaicin-induced [Ca(2+)](i) by >50% (p<0.05) and abolished the 17β-estradiol effect. By contrast, apoptotic DRG cells increased initial ATP-induced [Ca(2+)](i), flux four fold and abolished subsequent [Ca(2+)](i), responses to ATP stimulation (p<0.001). Capsaicin (100nM) induced [Ca(2+)](i) responses were totally abolished. The local presence of apoptotic DRG or human neuroblastoma cells induced differing abnormal ATP and capsaicin-mediated [Ca(2+)](i) fluxes in normal DRG. These findings support physically disconnected, non-diffusible cell-to-cell signaling. Further studies are needed to delineate the mechanism(s) of and model(s) of communication.

Histological assessments on the abnormalities of mouse epiphyseal chondrocytes with short term centrifugal loading.

PubMed

de Freitas, Paulo Henrique Luiz; Kojima, Taku; Ubaidus, Sobhan; Li, Minqi; Shang, Guangwei; Takagi, Ritsuo; Maeda, Takeyasu; Oda, Kimimitsu; Ozawa, Hidehiro; Amizuka, Norio

2007-08-01

We have examined the morphological changes in chondrocytes after exposure to experimental hypergravity. Tibial epiphyseal cartilages of 17-days-old mouse fetuses were exposed to centrifugation at 3G for 16 h mimicking hypergravitational environment (experimental group), or subjected to stationary cultures (control group). Centrifugation did not affect the sizes of epiphyseal cartilage, chondrocyte proliferation, type X collagen-positive hypertrophic zone, and the mRNA expressions of parathyroid hormone-related peptide and fibroblast growth factor receptor III. However, centrifuged chondrocytes showed abnormal morphology and aberrant spatial arrangements, resulting in disrupted chondrocytic columns. Through histochemical assessments, actin filaments were shown to distribute evenly along cell membranes of control proliferative chondrocytes, while chondrocytes subjected to centrifugal force developed a thicker layer of actin filaments. Transmission electron microscopic observations revealed spotty electron-dense materials underlying control chondrocytes' cell membranes, while experimental chondrocytes showed their thick layer. In the intracolumnar regions of the control cartilage, longitudinal electron-dense fibrils were associated with short cytoplasmic processes of normal chondrocytes, indicating assumed cell-tomatrix interactions. These extracellular fibrils were disrupted in the centrifuged samples. Summarizing, altered actin filaments associated with cell membranes, irregular cell shape and disappearance of intracolumnar extracellular fibrils suggest that hypergravity disturbs cell-to-matrix interactions in our cartilage model.

Effects of oxidative stress on hyperglycaemia-induced brain malformations in a diabetes mouse model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Ya; Wang, Guang; Han, Sha-Sha

Pregestational diabetes mellitus (PGDM) enhances the risk of fetal neurodevelopmental defects. However, the mechanism of hyperglycaemia-induced neurodevelopmental defects is not fully understood. In this study, several typical neurodevelopmental defects were identified in the streptozotocin-induced diabetes mouse model. The neuron-specific class III beta-tubulin/forkhead box P1-labelled neuronal differentiation was suppressed and glial fibrillary acidic protein-labelled glial cell lineage differentiation was slightly promoted in pregestational diabetes mellitus (PGDM) mice. Various concentrations of glucose did not change the U87 cell viability, but glial cell line-derived neurotrophic factor expression was altered with varying glucose concentrations. Mouse maternal hyperglycaemia significantly increased Tunel{sup +} apoptosis but didmore » not dramatically affect PCNA{sup +} cell proliferation in the process. To determine the cause of increased apoptosis, we determined the SOD activity, the expression of Nrf2 as well as its downstream anti-oxidative factors NQO1 and HO1, and found that all of them significantly increased in PGDM fetal brains compared with controls. However, Nrf2 expression in U87 cells was not significantly changed by different glucose concentrations. In mouse telencephalon, we observed the co-localization of Tuj-1 and Nrf2 expression in neurons, and down-regulating of Nrf2 in SH-SY5Y cells altered the viability of SH-SY5Y cells exposed to high glucose concentrations. Taken together, the data suggest that Nrf2-modulated antioxidant stress plays a crucial role in maternal hyperglycaemia-induced neurodevelopmental defects. - Highlights: • Typical neurodevelopmental defects could be observed in STZ-treated mouse fetuses. • Nrf2 played a crucial role in hyperglycaemia-induced brain malformations. • The effects of hyperglycaemia on neurons and glia cells were not same.« less

Supraphysiologic control over HIV-1 replication mediated by CD8 T cells expressing a re-engineered CD4-based chimeric antigen receptor

PubMed Central

Richardson, Max W.; Ellebrecht, Christoph T.; Glover, Joshua A.; Secreto, Anthony J.; Kulikovskaya, Irina; Yi, Yanjie; Wang, Jianbin; Dufendach, Keith A.; Holmes, Michael C.; Collman, Ronald G.

2017-01-01

HIV is adept at avoiding naturally generated T cell responses; therefore, there is a need to develop HIV-specific T cells with greater potency for use in HIV cure strategies. Starting with a CD4-based chimeric antigen receptor (CAR) that was previously used without toxicity in clinical trials, we optimized the vector backbone, promoter, HIV targeting moiety, and transmembrane and signaling domains to determine which components augmented the ability of T cells to control HIV replication. This re-engineered CAR was at least 50-fold more potent in vitro at controlling HIV replication than the original CD4 CAR, or a TCR-based approach, and substantially better than broadly neutralizing antibody-based CARs. A humanized mouse model of HIV infection demonstrated that T cells expressing optimized CARs were superior at expanding in response to antigen, protecting CD4 T cells from infection, and reducing viral loads compared to T cells expressing the original, clinical trial CAR. Moreover, in a humanized mouse model of HIV treatment, CD4 CAR T cells containing the 4-1BB costimulatory domain controlled HIV spread after ART removal better than analogous CAR T cells containing the CD28 costimulatory domain. Together, these data indicate that potent HIV-specific T cells can be generated using improved CAR design and that CAR T cells could be important components of an HIV cure strategy. PMID:29023549

Interaction of fluorescently labeled pyrrole-imidazole polyamide probes with fixed and living murine and human cells.

PubMed

Nozeret, Karine; Loll, François; Cardoso, Gildas Mouta; Escudé, Christophe; Boutorine, Alexandre S

2018-06-01

Pericentromeric heterochromatin plays important roles in controlling gene expression and cellular differentiation. Fluorescent pyrrole-imidazole polyamides targeting murine pericentromeric DNA (major satellites) can be used for the visualization of pericentromeric heterochromatin foci in live mouse cells. New derivatives targeting human repeated DNA sequences (α-satellites) were synthesized and their interaction with target DNA was characterized. The possibility to use major satellite and α -satellite binding polyamides as tools for staining pericentromeric heterochromatin was further investigated in fixed and living mouse and human cells. The staining that was previously observed using the mouse model was further characterized and optimized, but remained limited regarding the fluorophores that can be used. The promising results regarding the staining in the mouse model could not be extended to the human model. Experiments performed in human cells showed chromosomal DNA staining without selectivity. Factors limiting the use of fluorescent polyamides, in particular probe aggregation in the cytoplasm, were investigated. Results are discussed with regards to structure and affinity of probes, density of target sites and chromatin accessibility in both models. Copyright © 2018 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Short-term regular aerobic exercise reduces oxidative stress produced by acute in the adipose microvasculature.

PubMed

Robinson, Austin T; Fancher, Ibra S; Sudhahar, Varadarajan; Bian, Jing Tan; Cook, Marc D; Mahmoud, Abeer M; Ali, Mohamed M; Ushio-Fukai, Masuko; Brown, Michael D; Fukai, Tohru; Phillips, Shane A

2017-05-01

High blood pressure has been shown to elicit impaired dilation in the vasculature. The purpose of this investigation was to elucidate the mechanisms through which high pressure may elicit vascular dysfunction and determine the mechanisms through which regular aerobic exercise protects arteries against high pressure. Male C57BL/6J mice were subjected to 2 wk of voluntary running (~6 km/day) for comparison with sedentary controls. Hindlimb adipose resistance arteries were dissected from mice for measurements of flow-induced dilation (FID; with or without high intraluminal pressure exposure) or protein expression of NADPH oxidase II (NOX II) and superoxide dismutase (SOD). Microvascular endothelial cells were subjected to high physiological laminar shear stress (20 dyn/cm 2 ) or static condition and treated with ANG II + pharmacological inhibitors. Cells were analyzed for the detection of ROS or collected for Western blot determination of NOX II and SOD. Resistance arteries from exercised mice demonstrated preserved FID after high pressure exposure, whereas FID was impaired in control mouse arteries. Inhibition of ANG II or NOX II restored impaired FID in control mouse arteries. High pressure increased superoxide levels in control mouse arteries but not in exercise mouse arteries, which exhibited greater ability to convert superoxide to H 2 O 2 Arteries from exercised mice exhibited less NOX II protein expression, more SOD isoform expression, and less sensitivity to ANG II. Endothelial cells subjected to laminar shear stress exhibited less NOX II subunit expression. In conclusion, aerobic exercise prevents high pressure-induced vascular dysfunction through an improved redox environment in the adipose microvasculature. NEW & NOTEWORTHY We describe potential mechanisms contributing to aerobic exercise-conferred protection against high intravascular pressure. Subcutaneous adipose microvessels from exercise mice express less NADPH oxidase (NOX) II and more superoxide dismutase (SOD) and demonstrate less sensitivity to ANG II. In microvascular endothelial cells, shear stress reduced NOX II but did not influence SOD expression.

Par-aPKC-dependent and -independent mechanisms cooperatively control cell polarity, Hippo signaling, and cell positioning in 16-cell stage mouse embryos.

PubMed

Hirate, Yoshikazu; Hirahara, Shino; Inoue, Ken-Ichi; Kiyonari, Hiroshi; Niwa, Hiroshi; Sasaki, Hiroshi

2015-10-01

In preimplantation mouse embryos, the Hippo signaling pathway plays a central role in regulating the fates of the trophectoderm (TE) and the inner cell mass (ICM). In early blastocysts with more than 32 cells, the Par-aPKC system controls polarization of the outer cells along the apicobasal axis, and cell polarity suppresses Hippo signaling. Inactivation of Hippo signaling promotes nuclear accumulation of a coactivator protein, Yap, leading to induction of TE-specific genes. However, whether similar mechanisms operate at earlier stages is not known. Here, we show that slightly different mechanisms operate in 16-cell stage embryos. Similar to 32-cell stage embryos, disruption of the Par-aPKC system activated Hippo signaling and suppressed nuclear Yap and Cdx2 expression in the outer cells. However, unlike 32-cell stage embryos, 16-cell stage embryos with a disrupted Par-aPKC system maintained apical localization of phosphorylated Ezrin/Radixin/Moesin (p-ERM), and the effects on Yap and Cdx2 were weak. Furthermore, normal 16-cell stage embryos often contained apolar cells in the outer position. In these cells, the Hippo pathway was strongly activated and Yap was excluded from the nuclei, thus resembling inner cells. Dissociated blastomeres of 8-cell stage embryos form polar-apolar couplets, which exhibit different levels of nuclear Yap, and the polar cell engulfed the apolar cell. These results suggest that cell polarization at the 16-cell stage is regulated by both Par-aPKC-dependent and -independent mechanisms. Asymmetric cell division is involved in cell polarity control, and cell polarity regulates cell positioning and most likely controls Hippo signaling. © The Authors Development, Growth & Differentiation published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Society of Developmental Biologists.

Infectivity of five different types of macrophages by Leishmania infantum.

PubMed

Maia, C; Rolão, N; Nunes, M; Gonçalves, L; Campino, L

2007-08-01

Leishmania are intracellular parasites that multiply as the amastigote form in the macrophages of their vertebrate hosts. Since vaccines against leishmaniases are still under development, the control of these diseases relies on prompt diagnosis and chemotherapy in infected humans as well as in dogs, which are the main reservoir of Leishmania infantum, in Mediterranean countries. To establish the macrophage type to be used as an in vitro model for antileishmanial chemotherapeutic studies, we analysed the susceptibility of human peripheral blood derived macrophages, macrophages derived from mouse bone marrow, mouse peritoneal macrophages and macrophages differentiated from cell lines U-937 and DH82 to infection by two L. infantum strains, one obtained from a human leishmanial infection and other from a canine infection. Both strains displayed comparable behaviour in their capacity of infecting the different macrophage types. Human peripheral blood macrophages and DH82 cells were less infectable by both strains. U-937, mouse peritoneal macrophages and mouse bone marrow derived macrophages are the most active cells to phagocytose the parasites. However, U-937 cell line appears to be the most useful as Leishmania infection model providing an unlimited source of homogeneous host cells with reproducibility of the results, is less time consuming, less expensive and tolerate high doses of first line drugs for human and canine visceral leishmaniasis treatment.

Novel In Vivo Model for Combinatorial Fluorescence Labeling in Mouse Prostate

PubMed Central

Fang, Xiaolan; Gyabaah, Kenneth; Nickkholgh, Bita; Cline, J. Mark; Balaji, K.C.

2015-01-01

BACKGROUND The epithelial layer of prostate glands contains several types of cells, including luminal and basal cells. Yet there is paucity of animal models to study the cellular origin of normal or neoplastic development in the prostate to facilitate the treatment of heterogenous prostate diseases by targeting individual cell lineages. METHODS We developed a mouse model that expresses different types of fluorescent proteins (XFPs) specifically in prostatic cells. Using an in vivo stochastic fluorescent protein combinatorial strategy, XFP signals were expressed specifically in prostate of Protein Kinase D1 (PKD1) knock-out, K-RasG12D knock-in, and Phosphatase and tensin homolog (PTEN) and PKD1 double knock-out mice under the control of PB-Cre promoter. RESULTS In vivo XFP signals were observed in prostate of PKD1 knock-out, K-RasG12D knock-in, and PTEN PKD1 double knock-out mice, which developed normal, hyperplastic, and neoplastic prostate, respectively. The patchy expression pattern of XFPs in neoplasia tissue indicated the clonal origin of cancer cells in the prostate. CONCLUSIONS The transgenic mouse models demonstrate combinatorial fluorescent protein expression in normal and cancerous prostatic tissues. This novel prostate-specific fluorescent labeled mouse model, which we named Prorainbow, could be useful in studying benign and malignant pathology of prostate. PMID:25753731

Novel In Vivo model for combinatorial fluorescence labeling in mouse prostate.

PubMed

Fang, Xiaolan; Gyabaah, Kenneth; Nickkholgh, Bita; Cline, J Mark; Balaji, K C

2015-06-15

The epithelial layer of prostate glands contains several types of cells, including luminal and basal cells. Yet there is paucity of animal models to study the cellular origin of normal or neoplastic development in the prostate to facilitate the treatment of heterogenous prostate diseases by targeting individual cell lineages. We developed a mouse model that expresses different types of fluorescent proteins (XFPs) specifically in prostatic cells. Using an in vivo stochastic fluorescent protein combinatorial strategy, XFP signals were expressed specifically in prostate of Protein Kinase D1 (PKD1) knock-out, K-Ras(G) (12) (D) knock-in, and Phosphatase and tensin homolog (PTEN) and PKD1 double knock-out mice under the control of PB-Cre promoter. In vivo XFP signals were observed in prostate of PKD1 knock-out, K-Ras(G) (12) (D) knock-in, and PTEN PKD1 double knock-out mice, which developed normal, hyperplastic, and neoplastic prostate, respectively. The patchy expression pattern of XFPs in neoplasia tissue indicated the clonal origin of cancer cells in the prostate. The transgenic mouse models demonstrate combinatorial fluorescent protein expression in normal and cancerous prostatic tissues. This novel prostate-specific fluorescent labeled mouse model, which we named Prorainbow, could be useful in studying benign and malignant pathology of prostate. © 2015 Wiley Periodicals, Inc.

Characterization of the synthesis and expression of the GTA-kinase from transformed and normal rodent cells.

PubMed

Kerr, M; Fischer, J E; Purushotham, K R; Gao, D; Nakagawa, Y; Maeda, N; Ghanta, V; Hiramoto, R; Chegini, N; Humphreys-Beher, M G

1994-08-02

The murine transformed cell line YC-8 and beta-adrenergic receptor agonist (isoproternol) treated rat and mouse parotid gland acinar cells ectopically express cell surface beta 1-4 galactosyltransferase during active proliferation. This activity is dependent upon the expression of the GTA-kinase (p58) in these cells. Using total RNA, cDNA clones for the protein coding region of the kinase were isolated by reverse transcriptase-PCR cloning. DNA sequence analysis failed to show sequence differences with the normal homolog from mouse cells although Southern blot analysis of YC-8, and a second cell line KI81, indicated changes in the restriction enzyme digestion profile relative to murine cell lines which do not express cell surface galactosyltransferase. The rat cDNA clone from isoproterenol-treated salivary glands showed a high degree of protein and nucleic acid sequence homology to the GTA-kinase from both murine and human sources. Northern blot analysis of YC-8 and a control cell line LSTRA revealed the synthesis of a major 3.0 kb mRNA from both cell lines plus the unique expression of a 4.5 kb mRNA in the YC-8 cells. Reverse transcriptase-PCR of LSTRA and YC-8 confirmed the increased steady state levels of the GTA-kinase mRNA in YC-8. In the mouse, induction of cell proliferation by isoproterenol resulted in a 50-fold increase in steady state mRNA levels for the kinase over the low level of expression in quiescent cells. Expression of the rat 3' untranslated region in rat parotid cells in vitro led to an increased rate of DNA synthesis, cell number an ectopic expression of cell surface galactosyltransferase in the sense orientation. Antisense expression or vector alone did not alter growth characteristics of acinar cells. A polyclonal antibody monospecific to a murine amino terminal peptide sequence revealed a uniform distribution of GTA-kinase over the cytoplasm of acinar and duct cells of control mouse parotid glands. However, upon growth stimulation, kinase was detected primarily in a perinuclear and nuclear immunostaining pattern. Western blot analysis confirmed a translocation from a cytoplasmic localization in both LSTRA and quiescent salivary cells to a membrane-associated localization in YC-8 and proliferating salivary cells.

Acceleration of fusion in mouse palates by in vitro exposure to excess G

NASA Technical Reports Server (NTRS)

Duke, J.; Janer, L.; Campbell, M.

1984-01-01

Palatal shelves from 13- and 14-day mouse embryos were excised and cultured in contiguous pairs. Experimental cultures were exposed to 2.6 G in a culture centrifuge; controls were in the same incubator. After 24 hours, palates were prepared for light or electron microscopy. Scoring of paraffin sections according to the stage of fusion seen in the medial epithelial edges (MEE) showed that palates exposed to excess G were in more advanced stages of fusion than were controls. Ultrastructurally, control MEE had tightly apposed cell membranes and numerous desmosomes; in centrifuged MEE, desmosomes had been removed and there was much intercellular space. Nuclear membranes were intact in control MEE, but showed marked deterioration in MEE of centrifuged palates. Few lysosomes and no necrosis were seen in control MEE; centrifuged MEE had numerous lysosomes as well as necrotic cells. Basal lamina were intact in controls, but interrupted in centrifuged palates. The results confirm the hypothesis that gravitational increases speed up the differentiative process.

Estrogen receptor-mediated effects of a xenoestrogen, bisphenol A, on preimplantation mouse embryos.

PubMed

Takai, Y; Tsutsumi, O; Ikezuki, Y; Hiroi, H; Osuga, Y; Momoeda, M; Yano, T; Taketani, Y

2000-04-21

The effects of bisphenol A, a xenoestrogen widely used in industry and dentistry, were studied in early preimplantation mouse embryos. Two-cell mouse embryos were cultured with 100 pM to 100 microM bisphenol A with or without 100 nM tamoxifen and evaluated at 24-h intervals for their development to eight-cell and blastocyst stages. At 72 h, blastocysts were cultured for another 48 h without bisphenol A, and surface areas of trophoblast spread were measured. At 24 h, more embryos exposed to 3 nM bisphenol A than to controls had reached the eight-cell stage. At 48 h, more embryos exposed to 1 nM and 3 nM bisphenol A than to controls had become blastocysts. At 100 microM, bisphenol A decreased frequency of development to blastocysts. Tamoxifen counteracted both stimulatory and inhibitory effects of bisphenol A on blastocyst formation. Although bisphenol A did not alter blastocyst morphology or cell number, early exposure to 100 microM bisphenol A increased subsequent trophoblast areas. These findings suggest that bisphenol A may not only effect early embryonic development via estrogen receptors even at low, environmentally relevant doses, but also exert some late effects on subsequent development of these embryos. Copyright 2000 Academic Press.

Effects of alpha-lipoic acid on retinal ganglion cells, retinal thicknesses, and VEGF production in an experimental model of diabetes.

PubMed

Kan, Emrah; Alici, Ömer; Kan, Elif Kılıç; Ayar, Ahmet

2017-12-01

The purpose of the present study was to investigate the effect of alpha-lipoic acid (ALA) on the thicknesses of various retinal layers and on the numbers of retinal ganglion cells and vascular endothelial growth factor levels in experimental diabetic mouse retinas. Twenty-one male BALB/C mice were made diabetic by the intraperitoneal administration of streptozotocin (200 mg/kg). One week after the induction of diabetes, the mice were divided randomly into three groups: control group (non-diabetic mice treated with alpha-lipoic acid, n = 7), diabetic group (diabetic mice without treatment, n = 7), and alpha-lipoic acid treatment group (diabetic mice with alpha-lipoic acid treatment, n = 7). At the end of the 8th week, the thicknesses of the inner nuclear layer (INL), outer nuclear layer (ONL), and full-length retina were measured; also retinal ganglion cells and VEGF expressions were counted on the histological sections of the mouse retinas and compared with each other. The thicknesses of the full-length retina, ONL, and INL were significantly reduced in the diabetic group compared to the control and ALA treatment groups (p = 0.001), whereas the thicknesses of these layers did not show a significant difference between ALA treatment and control groups. The number of ganglion cells in the diabetic group was significantly lower than those in the control and ALA treatment groups (p = 0.001). The VEGF expression was significantly higher in the diabetic group and mostly observed in the ganglion cell and inner nuclear layers compared to the control and ALA treatment groups (p = 0.001). Therefore, the number of ganglion cells and VEGF levels did not show significant differences between the ALA treatment and control groups (p = 0.7). Our results show that alpha-lipoic acid treatment may have an impact on reducing VEGF levels, protecting ganglion cells, and preserving the thicknesses of the inner and outer layers in diabetic mouse retinas.

Expression of aquaporin-7 and aquaporin-9 in tanycyte cells and choroid plexus during mouse estrus cycle.

PubMed

Yaba, A; Sozen, B; Suzen, B; Demir, N

2017-03-01

Tanycytes are special ependymal cells located in the ventrolateral wall and floor of the third ventricle having processes extending nuclei that regulate reproductive functions and around of vessels in median eminance. The aquaporins (AQPs) are a family of transmembrane proteins that transport water and glycerol. AQP-7 and -9 are permeable to other small molecules as glycerol and therefore called aquaglyceroporins. In this study, we aimed to show localization of AQP-7 and -9 in epithelial cells of choroid plexus and tanycytes during female mouse estrus cycle. AQP-7 and -9 proteins were detected in α2 and β1 tanycytes in prœstrus stage. Interestingly, there is no staining in estrus stage in any type of tanycytes. We observed weak immunoreactivity in α1, α2 and β1 tanycyte cells in metestrus stage for AQP-7 and α1 for AQP-9 protein. AQP-7 and -9 showed intense immunoreactivity in α2, β1 and β2 tanycyte cells during diestrus stage. Consequently, AQP-7 and -9 showed differential staining pattern in different stages of mouse estrus cycle. In the light of our findings and other recent publications, we suggest that AQP-7 and -9-mediated glycerol transport in tanycyte cells might be under hormonal control to use glycerol as a potential energy substrate during mouse estrus cycle. Copyright © 2016. Published by Elsevier Masson SAS.

An electrophysiological study on the effects of Pa-1G (a phospholipase A(2)) from the venom of king brown snake, Pseudechis australis, on neuromuscular function.

PubMed

Fatehi, M; Rowan, E G; Harvey, A L

2002-01-01

The effects of Pa-1G, a phospholipase A(2) (PLA(2)) from the venom of the Australian king brown snake (Pseudechis australis) were determined on the release of acetylcholine, muscle resting membrane potential and motor nerve terminal action potential at mouse neuromuscular junction. Intracellular recording from endplate regions of mouse triangularis sterni nerve-muscle preparations revealed that Pa-1G (800 nM) significantly reduced the amplitude of endplate potentials within 10 min exposure. The quantal content of endplate potentials was decreased to 58+/-6% of control after 30 min exposure to 800 nM Pa-1G. The toxin also caused a partial depolarisation of mouse muscle fibres within 60 min exposure. Extracellular recording of action potentials at motor nerve terminals showed that Pa-1G reduced the waveforms associated with both sodium and potassium conductances. To investigate whether this was a direct or indirect effect of the toxin on these ionic currents, whole cell patch clamp experiments were performed using human neuroblastoma (SK-N-SH) cells and B82 mouse fibroblasts stably transfected with rKv1.2. Patch clamp recording experiments confirmed that potassium currents sensitive to alpha-dendrotoxin recorded from B82 cells and sodium currents in SK-N-SH cells were not affected by the toxin. Since neither facilitation of acetylcholine release at mouse neuromuscular junction nor depression of potassium currents in B82 cells has been observed, the apparent blockade of potassium currents at mouse motor nerve endings induced by the toxin is unlikely to be due to a selective block of potassium channels.

17β-Estradiol Promotes Schwann Cell Proliferation and Differentiation, Accelerating Early Remyelination in a Mouse Peripheral Nerve Injury Model

PubMed Central

Chen, Yan; Guo, Wenjie; Li, Wenjuan; Cheng, Meng; Hu, Ying; Xu, Wenming

2016-01-01

Estrogen induces oligodendrocyte remyelination in response to demyelination in the central nervous system. Our objective was to determine the effects of 17β-estradiol (E2) on Schwann cell function and peripheral nerve remyelination after injury. Adult male C57BL/6J mice were used to prepare the sciatic nerve transection injury model and were randomly categorized into control and E2 groups. To study myelination in vitro, dorsal root ganglion (DRG) explant culture was prepared using 13.5-day-old mouse embryos. Primary Schwann cells were isolated from the sciatic nerves of 1- to 3-day-old Sprague–Dawley rats. Immunostaining for myelin basic protein (MBP) expression and toluidine blue staining for myelin sheaths demonstrated that E2 treatment accelerates early remyelination in the “nerve bridge” region between the proximal and distal stumps of the transection injury site in the mouse sciatic nerve. The 5-bromo-2′-deoxyuridine incorporation assay revealed that E2 promotes Schwann cell proliferation in the bridge region and in the primary culture, which is blocked using AKT inhibitor MK2206. The in vitro myelination in the DRG explant culture determined showed that the MBP expression in the E2-treated group is higher than that in the control group. These results show that E2 promotes Schwann cell proliferation and myelination depending on AKT activation. PMID:27872858

Hes1 Is Required for Appropriate Morphogenesis and Differentiation during Mouse Thyroid Gland Development

PubMed Central

Carre, Aurore; Rachdi, Latif; Tron, Elodie; Richard, Bénédicte; Castanet, Mireille; Schlumberger, Martin; Bidart, Jean-Michel

2011-01-01

Notch signalling plays an important role in endocrine development, through its target gene Hes1. Hes1, a bHLH transcriptional repressor, influences progenitor cell proliferation and differentiation. Recently, Hes1 was shown to be expressed in the thyroid and regulate expression of the sodium iodide symporter (Nis). To investigate the role of Hes1 for thyroid development, we studied thyroid morphology and function in mice lacking Hes1. During normal mouse thyroid development, Hes1 was detected from E9.5 onwards in the median anlage, and at E11.5 in the ultimobranchial bodies. Hes1 −/− mouse embryos had a significantly lower number of Nkx2-1-positive progenitor cells (p<0.05) at E9.5 and at E11.5. Moreover, Hes1 −/− mouse embryos showed a significantly smaller total thyroid surface area (−40 to −60%) compared to wild type mice at all study time points (E9.5−E16.5). In both Hes1 −/− and wild type mouse embryos, most Nkx2-1-positive thyroid cells expressed the cell cycle inhibitor p57 at E9.5 in correlation with low proliferation index. In Hes1 −/− mouse embryos, fusion of the median anlage with the ultimobranchial bodies was delayed by 3 days (E16.5 vs. E13.5 in wild type mice). After fusion of thyroid anlages, hypoplastic Hes1 −/− thyroids revealed a significantly decreased labelling area for T4 (−78%) and calcitonin (−65%) normalized to Nkx2-1 positive cells. Decreased T4-synthesis might be due to reduced Nis labelling area (−69%). These findings suggest a dual role of Hes1 during thyroid development: first, control of the number of both thyrocyte and C-cell progenitors, via a p57-independent mechanism; second, adequate differentiation and endocrine function of thyrocytes and C-cells. PMID:21364918

Defective natural killer cell activity in a mouse model of eczema herpeticum.

PubMed

Kawakami, Yuko; Ando, Tomoaki; Lee, Jong-Rok; Kim, Gisen; Kawakami, Yu; Nakasaki, Tae; Nakasaki, Manando; Matsumoto, Kenji; Choi, Youn Soo; Kawakami, Toshiaki

2017-03-01

Patients with atopic dermatitis (AD) are susceptible to several viruses, including herpes simplex virus (HSV). Some patients experience 1 or more episodes of a severe skin infection caused by HSV termed eczema herpeticum (EH). There are numerous mouse models of AD, but no established model exists for EH. We sought to establish and characterize a mouse model of EH. We infected AD-like skin lesions with HSV1 to induce severe skin lesions in a dermatitis-prone mouse strain of NC/Nga. Gene expression was investigated by using a microarray and quantitative PCR; antibody titers were measured by means of ELISA; and natural killer (NK) cell, cytotoxic T-cell, regulatory T-cell, and follicular helper T-cell populations were evaluated by using flow cytometry. The role of NK cells in HSV1-induced development of severe skin lesions was examined by means of depletion and adoptive transfer. Inoculation of HSV1 induced severe erosive skin lesions in eczematous mice, which had an impaired skin barrier, but milder lesions in small numbers of normal mice. Eczematous mice exhibited lower NK cell activity but similar cytotoxic T-cell activity and humoral immune responses compared with normal mice. The role of NK cells in controlling HSV1-induced skin lesions was demonstrated by experiments depleting or transferring NK cells. A murine model of EH with an impaired skin barrier was established in this study. We demonstrated a critical role of defective NK activities in the development of HSV1-induced severe skin lesions in eczematous mice. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. All rights reserved.

Functional cis-regulatory modules encoded by mouse-specific endogenous retrovirus

PubMed Central

Sundaram, Vasavi; Choudhary, Mayank N. K.; Pehrsson, Erica; Xing, Xiaoyun; Fiore, Christopher; Pandey, Manishi; Maricque, Brett; Udawatta, Methma; Ngo, Duc; Chen, Yujie; Paguntalan, Asia; Ray, Tammy; Hughes, Ava; Cohen, Barak A.; Wang, Ting

2017-01-01

Cis-regulatory modules contain multiple transcription factor (TF)-binding sites and integrate the effects of each TF to control gene expression in specific cellular contexts. Transposable elements (TEs) are uniquely equipped to deposit their regulatory sequences across a genome, which could also contain cis-regulatory modules that coordinate the control of multiple genes with the same regulatory logic. We provide the first evidence of mouse-specific TEs that encode a module of TF-binding sites in mouse embryonic stem cells (ESCs). The majority (77%) of the individual TEs tested exhibited enhancer activity in mouse ESCs. By mutating individual TF-binding sites within the TE, we identified a module of TF-binding motifs that cooperatively enhanced gene expression. Interestingly, we also observed the same motif module in the in silico constructed ancestral TE that also acted cooperatively to enhance gene expression. Our results suggest that ancestral TE insertions might have brought in cis-regulatory modules into the mouse genome. PMID:28348391

Dual effects of fluoxetine on mouse early embryonic development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Chang-Woon; Department of Obstetrics and Gynecology, Samsung Changwon Hospital, Sungkyunkwan University, Changwon 630-723; Choe, Changyong

2012-11-15

Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50 μM) for different durations. When late 2-cells were incubated with 5 μM fluoxetine for 6 h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetinemore » (5 μM) over 24 h showed a reduction in blastocyst formation. The addition of fluoxetine (5 μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K{sup +} channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ∼ 30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Highlights: ► Short-term exposure of 2-cells to fluoxetine enhances mouse blastocyst formation. ► The enhancive effect of fluoxetine is resulted from CaMKII activation. ► Long-term exposure of 2-cells to fluoxetine decreases mouse blastocyst formation. ► The inhibitory effect of fluoxetine is mediated through TREK channel gating.« less

Interaction of primary mast cells with Borrelia burgdorferi (sensu stricto): role in transmission and dissemination in C57BL/6 mice.

PubMed

Bernard, Quentin; Wang, Zhenping; Di Nardo, Anna; Boulanger, Nathalie

2017-06-27

Borrelia burgdorferi (sensu lato), the causative agent of Lyme borreliosis is a bacterium transmitted by hard ticks, Ixodes spp. Bacteria are injected into the host skin during the tick blood meal with tick saliva. There, Borrelia and saliva interact together with skin cells such as keratinocytes, fibroblasts, mast cells and other specific immune cells before disseminating to target organs. To study the role of mast cells in the transmission of Lyme borreliosis, we isolated mouse primary mast cells from bone marrow and incubated them in the presence of Borrelia burgdorferi (sensu stricto) and tick salivary gland extract. We further analyzed their potential role in vivo, in a mouse model of deficient in mast cells (Kit wsh-/- mice). To our knowledge, we report here for the first time the bacteria ability to induce the inflammatory response of mouse primary mast cells. We show that OspC, a major surface lipoprotein involved in the early transmission of Borrelia, induces the degranulation of primary mast cells but has a limited effect on the overall inflammatory response of these cells. In contrast, whole bacteria have an opposite effect. We also show that mast cell activation is significantly inhibited by tick salivary gland extract. Finally, we demonstrate that mast cells are likely not the only host cells involved in the early transmission and dissemination of Borrelia since the use of mast cell deficient Kit wsh-/- mice shows a limited impact on these two processes in the context of this mouse genetic background. The absence of mast cells did not change the replication rate of Borrelia in the skin. However, in the absence of mast cells, Borrelia dissemination to the joints was faster. Mast cells do not control skin bacterial proliferation during primary infection and the establishment of the primary infection, as shown in the C57BL/6 mouse model studied. Nevertheless, the Borrelia induced cytotokine modulation on mast cells might be involved in long term and/or repeated infections and protect from Lyme borreliosis due to the development of a hypersensitivity to tick saliva.

Exacerbation of Autoimmune Thyroiditis by CTLA-4 Blockade: A Role for IFNγ-Induced Indoleamine 2, 3-Dioxygenase.

PubMed

Sharma, Rajni; Di Dalmazi, Giulia; Caturegli, Patrizio

2016-08-01

Cytotoxic T-lymphocyte associated protein 4 (CTLA-4) is a negative regulator of immune responses that suppresses the activity of effector T cells and contributes to the maintenance of self tolerance. When blocked therapeutically, CTLA-4 leads to an overall activation of T cells that has been exploited for cancer control, a control associated however with a variety of immune-related side effects such as autoimmune thyroiditis. To investigate the mechanism(s) underlying this form of thyroiditis, we used the NOD-H2(h4) mouse, a model that develops thyroiditis at very high incidence after addition of iodine to the drinking water. NOD-H2(h4) mice were started on drinking water supplemented with 0.05% sodium iodide when 8 weeks old and then injected with a hamster monoclonal antibody against mouse CTLA-4, polyclonal hamster immunoglobulins, or phosphate buffered saline when 11 weeks old. One month later (15 weeks of age), mice were sacrificed to assess thyroiditis, general immune responses in blood and spleen, and expression of indoleamine 2, 3-dioxygenase (IDO) in the thyroid and in isolated antigen-presenting cells after stimulation with interferon gamma. The study also analyzed IDO expression in four autopsy cases of metastatic melanoma who had received treatment with a CTLA-4 blocking antibody, and six surgical pathology Hashimoto thyroiditis controls. CTLA-4 blockade worsened autoimmune thyroiditis, as assessed by a greater incidence, a more aggressive mononuclear cell infiltration in thyroids, and higher thyroglobulin antibody levels when compared to the control groups. CTLA-4 blockade also expanded the proportion of splenic CD4+ effector T cells, as well as the production of interleukin (IL)-2, interferon gamma, IL-10, and IL-13 cytokines. Interestingly, CTLA-4 blockade induced a strong expression of IDO in mouse and human thyroid glands, an expression that could represent a counter-regulatory mechanism to protect against the inflammatory environment. This study shows that CTLA-4 blockade exacerbates the iodine-accelerated form of thyroiditis typical of the NOD-H2(h4) mouse. The study could also have implications for cancer patients who develop thyroiditis as an immune-related adverse event after CTLA-4 blockade.

Metabolic Impact of Rapamycin (Sirolimus) and B-Estradiol Using Mouse Embryonic Fibroblasts as a Model for Lymphangioleiomyomatosis.

PubMed

Marsh, Katherine M; Schipper, David; Ferng, Alice S; Johnson, Kitsie; Fisher, Julia; Knapp, Shannon; Dicken, Destiny; Khalpey, Zain

2017-08-01

Lymphangioleiomyomatosis (LAM) is a rare, progressive cystic lung disease that predominantly affects women of childbearing age. Exogenous rapamycin (sirolimus) has been shown to improve clinical outcomes and was recently approved to treat LAM, whereas estrogen (E 2 ) is implicated in disease progression. No consistent metabolic model currently exists for LAM, therefore wild-type mouse embryonic fibroblasts (MEF +/+) and TSC2 knockout cells (MEF -/-) were used in this study as a model for LAM. Oxygen consumption rates (OCR) and redox potential were measured to determine metabolic state across control cells, MEF +/+ and -/- cells treated with rapamycin (Rapa), and MEF +/+ and -/- cells treated with E 2 . An XF96 extracellular flux analyzer from Seahorse Bioscience ® was used to measure OCR, and a RedoxSYS™ ORP was used to measure redox potential. OCR of MEF -/- cells treated with rapamycin (MEF -/- Rapa) versus MEF -/- control were significantly lower across all conditions. The static oxidation reduction potential of the MEF -/- Rapa group was also lower, approaching significance. The coupling efficiency and ratio of ATP-linked respiration to maximum respiration were statistically lower in MEF -/- Rapa compared to MEF +/+ Rapa. There were no significant metabolic findings across any of the MEF cells treated with E 2 . MEF -/- control cells versus MEF +/+ control cells were not found to significantly differ. MEF cells are thought to be a feasible metabolic model for LAM, which has implications for future pharmacologic and biologic testing.

Effects of diamines on ornithine decarboxylase activity in control and virally transformed mouse fibroblasts.

PubMed Central

Bethell, D R; Pegg, A E

1979-01-01

1. The induction of ornithine decarboxylase activity in mouse 3T3 fibroblasts or an SV-40 transformed 3T3 cell line by serum was prevented by addition of the naturally occurring polyamines putrescine (butane-1,4-diamine) and spermidine. Much higher concentrations of these amines were required to fully suppress ornithine decarboxylase activity in the transformed SV-3T3 cells than in the 3T3 fibroblasts. 2. Synthetic alpha omega-diamines with 3--12 carbon atoms also prevented the increase in ornithine decarboxylase activity induced by serum in these cells. The longer chain diamines were somewhat more potent than propane-1,3-diamine in this effect, but the synthetic diamines were less active than putrescine in the 3T3 cells. There was little difference between the responses of 3T3 and SV-3T3 cells to the synthetic diamines propane-1,3-diamine and heptane-1,7-diamine. 3. These results are discussed in relation to the control of polyamine synthesis in mammalian cells. PMID:486108

Thymic hormone-containing cells. Characterization and localization of serum thymic factor in young mouse thymus studied by monoclonal antibodies

PubMed Central

1982-01-01

The characterization and distribution of cells containing the serum thymic factor (FTS) in the thymus of young mice was studied by immunofluorescence using monoclonal anti-FTS antibodies. FTS+ cells were distributed throughout the thymic parenchyma but were more frequent in the medullary region than in the cortex. FTS-containing cells presented a stellate or globular aspect, and some of them exhibited fluorescent cytoplasmic granules. The epithelial nature of FTS+ cells was confirmed by double-labeling experiments using an anti- keratin antiserum (as an epithelial cell marker). Nevertheless, only a minority of keratin-positive epithelial reticular cells contained FTS. All controls, including the incubation of sections from nonthymic tissues with the anti-FTS antibodies, were negative. Taken together, these results confirm the exclusive localization of FTS-containing cells within the mouse thymus. PMID:7047671

Down-regulation of anandamide hydrolase in mouse uterus by sex hormones.

PubMed

MacCarrone, M; De Felici, M; Bari, M; Klinger, F; Siracusa, G; Finazzi-Agrò, A

2000-05-01

Endocannabinoids are an emerging class of lipid mediators, which mimic several effects of cannabinoids. Anandamide (arachidonoylethanolamide) is a major endocannabinoid, which has been shown to impair pregnancy and embryo development. The activity of anandamide is controlled by cellular uptake through a specific transporter and intracellular degradation by the enzyme anandamide hydrolase (fatty acid amide hydrolase, FAAH). We characterized FAAH in mouse uterus by radiochromatographic and immunochemical techniques, showing that the enzyme is confined to the epithelium and its activity decreases appreciably during pregnancy or pseudopregnancy because of lower gene expression at the translational level. Ovariectomy prevented the decrease in FAAH, and both progesterone and estrogen further reduced its basal levels, suggesting hormonal control of the enzyme. Anandamide was shown to induce programmed cell death in mouse blastocysts, through a pathway independent of type-1 cannabinoid receptor. Blastocysts, however, have a specific anandamide transporter and FAAH, which scavenge this lipid. Taken together, these results provide evidence of an interplay between endocannabinoids and sex hormones in pregnancy. These findings may also be relevant for human fertility, as epithelial cells from healthy human uterus showed FAAH activity and expression, which in adenocarcinoma cells was increased fivefold.

Natural killer cell lines preferentially kill clonogenic multiple myeloma cells and decrease myeloma engraftment in a bioluminescent xenograft mouse model.

PubMed

Swift, Brenna E; Williams, Brent A; Kosaka, Yoko; Wang, Xing-Hua; Medin, Jeffrey A; Viswanathan, Sowmya; Martinez-Lopez, Joaquin; Keating, Armand

2012-07-01

Novel therapies capable of targeting drug resistant clonogenic MM cells are required for more effective treatment of multiple myeloma. This study investigates the cytotoxicity of natural killer cell lines against bulk and clonogenic multiple myeloma and evaluates the tumor burden after NK cell therapy in a bioluminescent xenograft mouse model. The cytotoxicity of natural killer cell lines was evaluated against bulk multiple myeloma cell lines using chromium release and flow cytometry cytotoxicity assays. Selected activating receptors on natural killer cells were blocked to determine their role in multiple myeloma recognition. Growth inhibition of clonogenic multiple myeloma cells was assessed in a methylcellulose clonogenic assay in combination with secondary replating to evaluate the self-renewal of residual progenitors after natural killer cell treatment. A bioluminescent mouse model was developed using the human U266 cell line transduced to express green fluorescent protein and luciferase (U266eGFPluc) to monitor disease progression in vivo and assess bone marrow engraftment after intravenous NK-92 cell therapy. Three multiple myeloma cell lines were sensitive to NK-92 and KHYG-1 cytotoxicity mediated by NKp30, NKp46, NKG2D and DNAM-1 activating receptors. NK-92 and KHYG-1 demonstrated 2- to 3-fold greater inhibition of clonogenic multiple myeloma growth, compared with killing of the bulk tumor population. In addition, the residual colonies after treatment formed significantly fewer colonies compared to the control in a secondary replating for a cumulative clonogenic inhibition of 89-99% at the 20:1 effector to target ratio. Multiple myeloma tumor burden was reduced by NK-92 in a xenograft mouse model as measured by bioluminescence imaging and reduction in bone marrow engraftment of U266eGFPluc cells by flow cytometry. This study demonstrates that NK-92 and KHYG-1 are capable of killing clonogenic and bulk multiple myeloma cells. In addition, multiple myeloma tumor burden in a xenograft mouse model was reduced by intravenous NK-92 cell therapy. Since multiple myeloma colony frequency correlates with survival, our observations have important clinical implications and suggest that clinical studies of NK cell lines to treat MM are warranted.

Genetic mouse embryo assay: improving performance and quality testing for assisted reproductive technology (ART) with a functional bioassay.

PubMed

Gilbert, Rebecca S; Nunez, Brandy; Sakurai, Kumi; Fielder, Thomas; Ni, Hsiao-Tzu

2016-03-24

Growing concerns about safety of ART on human gametes, embryos, clinical outcomes and long-term health of offspring require improved methods of risk assessment to provide functionally relevant assays for quality control testing and pre-clinical studies prior to clinical implementation. The one-cell mouse embryo assay (MEA) is the most widely used for development and quality testing of human ART products; however, concerns exist due to the insensitivity/variability of this bioassay which lacks standardization and involves subjective analysis by morphology alone rather than functional analysis of the developing embryos. We hypothesized that improvements to MEA by the use of functional molecular biomarkers could enhance sensitivity and improve detection of suboptimal materials/conditions. Fresh one-cell transgenic mouse embryos with green fluorescent protein (GFP) expression driven by Pou6f1 or Cdx2 control elements were harvested and cultured to blastocysts in varied test and control conditions to compare assessment by standard morphology alone versus the added dynamic expression of GFP for screening and selection of critical raw materials and detection of suboptimal culture conditions. Transgenic mouse embryos expressing functionally relevant biomarkers of normal early embryo development can be used to monitor the developmental impact of culture conditions. This novel approach provides a superior MEA that is more meaningful and sensitive for detection of embryotoxicity than morphological assessment alone.

Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong, Yan; Hirane, Miku; Araki, Mutsumi

2014-04-04

Highlights: • LPA{sub 5} inhibits the cell growth and motile activities of 3T3 cells. • LPA{sub 5} suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA{sub 5} on the cell motile activities inhibited by LPA{sub 1} in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA{sub 5} in 3T3 cells. • LPA signaling via LPA{sub 5} acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA{sub 1}–LPA{sub 6}) mediates a variety of biological functions, including cellmore » migration. Recently, we have reported that LPA{sub 1} inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA{sub 5} in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA{sub 1} and LPA{sub 5} on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA{sub 5} may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA{sub 1}.« less

Using Genetic Mouse Models to Gain Insight into Glaucoma: Past Results and Future Possibilities

PubMed Central

Fernandes, Kimberly A.; Harder, Jeffrey M.; Williams, Pete A.; Rausch, Rebecca L.; Kiernan, Amy E.; Nair, K. Saidas; Anderson, Michael G.; John, Simon W.; Howell, Gareth R.; Libby, Richard T.

2015-01-01

While all forms of glaucoma are characterized by a specific pattern of retinal ganglion cell death, they are clinically divided into several distinct subclasses, including normal tension glaucoma, primary open angle glaucoma, congenital glaucoma, and secondary glaucoma. For each type of glaucoma there are likely numerous molecular pathways that control susceptibility to the disease. Given this complexity, a single animal model will never precisely model all aspects of all the different types of human glaucoma. Therefore, multiple animal models have been utilized to study glaucoma but more are needed. Because of the powerful genetic tools available to use in the laboratory mouse, it has proven to be a highly useful mammalian system for studying the pathophysiology of human disease. The similarity between human and mouse eyes coupled with the ability to use a combination of advanced cell biological and genetic tools in mice have led to a large increase in the number of studies using mice to model specific glaucoma phenotypes. Over the last decade, numerous new mouse models and genetic tools have emerged, providing important insight into the cell biology and genetics of glaucoma. In this review, we describe available mouse genetic models that can be used to study glaucoma-relevant disease/pathobiology. Furthermore, we discuss how these models have been used to gain insights into ocular hypertension (a major risk factor for glaucoma) and glaucomatous retinal ganglion cell death. Finally, the potential for developing new mouse models and using advanced genetic tools and resources for studying glaucoma are discussed. PMID:26116903

JMJD1C Ensures Mouse Embryonic Stem Cell Self-Renewal and Somatic Cell Reprogramming through Controlling MicroRNA Expression.

PubMed

Xiao, Feng; Liao, Bing; Hu, Jing; Li, Shuang; Zhao, Haixin; Sun, Ming; Gu, Junjie; Jin, Ying

2017-09-12

The roles of histone demethylases (HDMs) for the establishment and maintenance of pluripotency are incompletely characterized. Here, we show that JmjC-domain-containing protein 1c (JMJD1C), an H3K9 demethylase, is required for mouse embryonic stem cell (ESC) self-renewal. Depletion of Jmjd1c leads to the activation of ERK/MAPK signaling and epithelial-to-mesenchymal transition (EMT) to induce differentiation of ESCs. Inhibition of ERK/MAPK signaling rescues the differentiation phenotype caused by Jmjd1c depletion. Mechanistically, JMJD1C, with the help of pluripotency factor KLF4, maintains ESC identity at least in part by regulating the expression of the miR-200 family and miR-290/295 cluster to suppress the ERK/MAPK signaling and EMT. Additionally, we uncover that JMJD1C ensures efficient generation and maintenance of induced pluripotent stem cells, at least partially through controlling the expression of microRNAs. Collectively, we propose an integrated model of epigenetic and transcriptional control mediated by the H3K9 demethylase for ESC self-renewal and somatic cell reprogramming. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Cyclin B in mouse oocytes and embryos: importance for human reproduction and aneuploidy.

PubMed

Polański, Zbigniew; Homer, Hayden; Kubiak, Jacek Z

2012-01-01

Oocyte maturation and early embryo development require precise coordination between cell cycle progression and the developmental programme. Cyclin B plays a major role in this process: its accumulation and degradation is critical for driving the cell cycle through activation and inactivation of the major cell cycle kinase, CDK1. CDK1 activation is required for M-phase entry whereas its inactivation leads to exit from M-phase. The tempo of oocyte meiotic and embryonic mitotic divisions is set by the rate of cyclin B accumulation and the timing of its destruction. By controlling when cyclin B destruction is triggered and by co-ordinating this with the completion of chromosome alignment, the spindle assembly checkpoint (SAC) is a critical quality control system important for averting aneuploidy and for building in the flexibility required to better integrate cell cycle progression with development. In this review we focus on cyclin B metabolism in mouse oocytes and embryos and illustrate how the cell cycle-powered clock (in fact cyclin B-powered clock) controls oocyte maturation and early embryo development, thereby providing important insight into human reproduction and potential causes of Down syndrome.

Thymoquinone suppresses metastasis of melanoma cells by inhibition of NLRP3 inflammasome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmad, Israr; Muneer, Kashiff M.; Tamimi, Iman A.

2013-07-01

The inflammasome is a multi-protein complex which when activated regulates caspase-1 activation and IL-1β and IL-18 secretion. The NLRP3 (NACHT, LRR, and pyrin domain-containing protein 3) inflammasome is constitutively assembled and activated in human melanoma cells. We have examined the inhibitory effect of thymoquinone (2-isopropyl-5-methylbenzo-1,4-quinone), a major ingredient of black seed obtained from the plant Nigella sativa on metastatic human (A375) and mouse (B16F10) melanoma cell lines. We have assessed whether thymoquinone inhibits metastasis of melanoma cells by targeting NLRP3 subunit of inflammasomes. Using an in vitro cell migration assay, we found that thymoquinone inhibited the migration of both humanmore » and mouse melanoma cells. The inhibitory effect of thymoquinone on metastasis was also observed in vivo in B16F10 mouse melanoma model. The inhibition of migration of melanoma cells by thymoquinone was accompanied by a decrease in expression of NLRP3 inflammasome resulting in decrease in proteolytic cleavage of caspase-1. Inactivation of caspase-1 by thymoquinone resulted in inhibition of IL-1β and IL-18. Treatment of mouse melanoma cells with thymoquinone also inhibited NF-κB activity. Furthermore, inhibition of reactive oxygen species (ROS) by thymoquinone resulted in partial inactivation of NLRP3 inflammasome. Thus, thymoquinone exerts its inhibitory effect on migration of human and mouse melanoma cells by inhibition of NLRP3 inflammasome. Thus, our results indicate that thymoquinone can be a potential immunotherapeutic agent not only as an adjuvant therapy for melanoma, but also, in the control and prevention of metastatic melanoma. - Highlights: • Thymoquinone causes inhibition of migration of melanoma cells. • Thymoquinone causes inhibition of metastasis in vivo. • Thymoquinone causes inhibition of migration by activation of NLRP3 inflammasome.« less

Genetic analysis of Ras genes in epidermal development and tumorigenesis

PubMed Central

Drosten, Matthias; Lechuga, Carmen G; Barbacid, Mariano

2013-01-01

Proliferation and differentiation of epidermal keratinocytes are tightly controlled to ensure proper development and homeostasis of the epidermis. The Ras family of small GTPases has emerged as a central node in the coordination of cell proliferation in the epidermis. Recent genetic evidence from mouse models has revealed that the intensity of Ras signaling modulates the proliferative capacity of epidermal keratinocytes. Interfering with Ras signaling either by combined elimination of the 3 Ras genes from the basal layer of the epidermis or by overexpression of dominant-negative Ras isoforms caused epidermal thinning due to hypoproliferation of keratinocytes. In contrast, overexpression of oncogenic Ras mutants in different epidermal cell layers led to hyperproliferative phenotypes including the development of papillomas and squamous cell carcinomas. Here, we discuss the value of loss- and gain-of-function studies in mouse models to assess the role of Ras signaling in the control of epidermal proliferation. PMID:24150175

Expression of hepatitis B virus 1.3-fold genome plasmid in an SV40 T-antigen-immortalized mouse hepatic cell line

PubMed Central

Song, Xiu-Guang; Bian, Peng-Fei; Yu, Shu-Li; Zhao, Xiu-Hua; Xu, Wei; Bu, Xue-Hui; Li, Xia; Ma, Li-Xian

2013-01-01

AIM: To investigate the expression of the hepatitis B virus (HBV) 1.3-fold genome plasmid (pHBV1.3) in an immortalized mouse hepatic cell line induced by SV40 T-antigen (SV40T) expression. METHODS: Mouse hepatic cells were isolated from mouse liver tissue fragments from 3-5 d old Kunming mice by the direct collagenase digestion method and cultured in vitro. The pRSV-T plasmid was transfected into mouse hepatic cells to establish an SV40LT-immortalized mouse hepatic cell line. The SV40LT-immortalized mouse hepatic cells were identified and transfected with the pHBV1.3 plasmid. The levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in the supernatant were determined by an electrochemiluminescence immunoassay at 24, 48, 72 and 96 h after transfection. The expressions of HBsAg and hepatitis B c antigen (HBcAg) in the cells were investigated by indirect immunofluorescence analysis. The presence of HBV DNA replication intermediates in the transfected cells and viral particles in the supernatant of the transfected cell cultures was monitored using the Southern hybridization assay and transmission electronic microscopy, respectively. RESULTS: The pRSV-T plasmid was used to immortalize mouse hepatocytes and an SV40LT-immortalized mouse hepatic cell line was successfully established. SV40LT-immortalized mouse hepatic cells have the same morphology and growth characteristics as primary mouse hepatic cells can be subcultured and produce albumin and cytokeratin-18 in vitro. Immortalized mouse hepatic cells did not show the characteristics of tumor cells, as alpha-fetoprotein levels were comparable (0.58 ± 0.37 vs 0.61 ± 0.31, P = 0.37). SV40LT-immortalized mouse hepatic cells were then transfected with the pHBV1.3 plasmid, and it was found that the HBV genome replicated in SV40LT-immortalized mouse hepatic cells. The levels of HBsAg and HBeAg continuously increased in the supernatant after the transfection of pHBV1.3, and began to decrease 72 h after transfection. The expressions of HBsAg and HBcAg were observed in the pHBV1.3-transfected cells. HBV DNA replication intermediates were also observed at 72 h after transfection, including relaxed circular DNA, double-stranded DNA and single-stranded DNA. Furthermore, a few 42 nm Dane particles, as well as many 22 nm subviral particles with a spherical or filamentous shape, were detected in the supernatant. CONCLUSION: SV40T expression can immortalize mouse hepatic cells, and the pHBV1.3-transfected SV40T-immortalized mouse hepatic cell line can be a new in vitro cell model. PMID:24307795

Expression of hepatitis B virus 1.3-fold genome plasmid in an SV40 T-antigen-immortalized mouse hepatic cell line.

PubMed

Song, Xiu-Guang; Bian, Peng-Fei; Yu, Shu-Li; Zhao, Xiu-Hua; Xu, Wei; Bu, Xue-Hui; Li, Xia; Ma, Li-Xian

2013-11-28

To investigate the expression of the hepatitis B virus (HBV) 1.3-fold genome plasmid (pHBV1.3) in an immortalized mouse hepatic cell line induced by SV40 T-antigen (SV40T) expression. Mouse hepatic cells were isolated from mouse liver tissue fragments from 3-5 d old Kunming mice by the direct collagenase digestion method and cultured in vitro. The pRSV-T plasmid was transfected into mouse hepatic cells to establish an SV40LT-immortalized mouse hepatic cell line. The SV40LT-immortalized mouse hepatic cells were identified and transfected with the pHBV1.3 plasmid. The levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in the supernatant were determined by an electrochemiluminescence immunoassay at 24, 48, 72 and 96 h after transfection. The expressions of HBsAg and hepatitis B c antigen (HBcAg) in the cells were investigated by indirect immunofluorescence analysis. The presence of HBV DNA replication intermediates in the transfected cells and viral particles in the supernatant of the transfected cell cultures was monitored using the Southern hybridization assay and transmission electronic microscopy, respectively. The pRSV-T plasmid was used to immortalize mouse hepatocytes and an SV40LT-immortalized mouse hepatic cell line was successfully established. SV40LT-immortalized mouse hepatic cells have the same morphology and growth characteristics as primary mouse hepatic cells can be subcultured and produce albumin and cytokeratin-18 in vitro. Immortalized mouse hepatic cells did not show the characteristics of tumor cells, as alpha-fetoprotein levels were comparable (0.58 ± 0.37 vs 0.61 ± 0.31, P = 0.37). SV40LT-immortalized mouse hepatic cells were then transfected with the pHBV1.3 plasmid, and it was found that the HBV genome replicated in SV40LT-immortalized mouse hepatic cells. The levels of HBsAg and HBeAg continuously increased in the supernatant after the transfection of pHBV1.3, and began to decrease 72 h after transfection. The expressions of HBsAg and HBcAg were observed in the pHBV1.3-transfected cells. HBV DNA replication intermediates were also observed at 72 h after transfection, including relaxed circular DNA, double-stranded DNA and single-stranded DNA. Furthermore, a few 42 nm Dane particles, as well as many 22 nm subviral particles with a spherical or filamentous shape, were detected in the supernatant. SV40T expression can immortalize mouse hepatic cells, and the pHBV1.3-transfected SV40T-immortalized mouse hepatic cell line can be a new in vitro cell model.

Transforming growth factor-β signalling controls human breast cancer metastasis in a zebrafish xenograft model.

PubMed

Drabsch, Yvette; He, Shuning; Zhang, Long; Snaar-Jagalska, B Ewa; ten Dijke, Peter

2013-11-07

The transforming growth factor beta (TGF-β) signalling pathway is known to control human breast cancer invasion and metastasis. We demonstrate that the zebrafish xenograft assay is a robust and dependable animal model for examining the role of pharmacological modulators and genetic perturbation of TGF-β signalling in human breast tumour cells. We injected cancer cells into the embryonic circulation (duct of cuvier) and examined their invasion and metastasis into the avascular collagenous tail. Various aspects of the TGF-β signalling pathway were blocked by chemical inhibition, small interfering RNA (siRNA), or small hairpin RNA (shRNA). Analysis was conducted using fluorescent microscopy. Breast cancer cells with different levels of malignancy, according to in vitro and in vivo mouse studies, demonstrated invasive and metastatic properties within the embryonic zebrafish model that nicely correlated with their differential tumourigenicity in mouse models. Interestingly, MCF10A M2 and M4 cells invaded into the caudal hematopoietic tissue and were visible as a cluster of cells, whereas MDA MB 231 cells invaded into the tail fin and were visible as individual cells. Pharmacological inhibition with TGF-β receptor kinase inhibitors or tumour specific Smad4 knockdown disturbed invasion and metastasis in the zebrafish xenograft model and closely mimicked the results we obtained with these cells in a mouse metastasis model. Inhibition of matrix metallo proteinases, which are induced by TGF-β in breast cancer cells, blocked invasion and metastasis of breast cancer cells. The zebrafish-embryonic breast cancer xenograft model is applicable for the mechanistic understanding, screening and development of anti-TGF-β drugs for the treatment of metastatic breast cancer in a timely and cost-effective manner.

Evidence for functional inter-relationships between FOXP3, leukaemia inhibitory factor, and axotrophin/MARCH-7 in transplantation tolerance.

PubMed

Muthukumarana, Poorni A D S; Lyons, Gary E; Miura, Yuji; Thompson, Lorraine H; Watson, Tracy; Green, Colin J; Shurey, Sandra; Hess, Allan D; Rosengard, Bruce R; Metcalfe, Su M

2006-12-20

In an ex vivo mouse model, regulatory transplantation tolerance is not only linked to Foxp3, but also to release of leukaemia inhibitory factor (LIF) and to expression of axotrophin (also known as MARCH-7), a putative ubiquitin E3 ligase associated with feedback control of T cell activation and of T cell-derived LIF. Given this coordinate correlation with tolerance, we now ask if Foxp3 expression is influenced by LIF or by axotrophin. In spleen cells from allo-rejected mice we found that exogenous LIF reduced interferon gamma release in response to donor antigen by 50%, but LIF had no direct effect on levels of Foxp3 protein in allo-primed cells that were either tolerant, or aggressive, for donor antigen. However, we did find an effect of axotrophin on Foxp3: in the axotrophin null mouse, thymic Foxp3 transcripts were reduced compared to axotrophin wildtype littermates. To test whether these findings in the mouse were of potential significance in man we measured transcript levels of axotrophin and LIF in peripheral blood cell samples collected for a recently published clinical study concerning haematopoietic stem cell recipients. In controls, human peripheral blood CD4+CD25+cells contained significantly more FOXP3 and axotrophin than CD4+CD25-cells. In bone marrow autograft recipients, where peripheral blood cell samples directly represent both the grafted tissue and the immune response, both FOXP3 and axotrophin negatively correlated with graft versus host disease (GVHD). These data suggest that (i) thymic Foxp3+T cell development is influenced by axotrophin; and (ii) clinical auto-GVHD inversely correlates with axotrophin transcript expression as has been previously reported for FOXP3.

SH2 domain-containing adaptor protein B expressed in dendritic cells is involved in T-cell homeostasis by regulating dendritic cell-mediated Th2 immunity.

PubMed

Ahmed, Md Selim; Kang, Myeong-Ho; Lee, Ezra; Park, Yujin; Jeong, Yideul; Bae, Yong-Soo

2017-01-01

The Src homology 2 domain-containing adaptor protein B (SHB) is widely expressed in immune cells and acts as an important regulator for hematopoietic cell function. SHB silencing induces Th2 immunity in mice. SHB is also involved in T-cell homeostasis in vivo . However, SHB has not yet been studied and addressed in association with dendritic cells (DCs). The effects of SHB expression on the immunogenicity of DCs were assessed by Shb gene silencing in mouse bone marrow-derived DCs (BMDCs). After silencing, surface phenotype, cytokine expression profile, and T-cell stimulation capacity of BMDCs were examined. We investigated the signaling pathways involved in SHB expression during BMDC development. We also examined the immunogenicity of SHB-knockdown (SHB KD ) BMDCs in a mouse atopic dermatitis model. SHB was steadily expressed in mouse splenic DCs and in in vitro -generated BMDCs in both immature and mature stages. SHB expression was contingent on activation of the mitogen- activated protein kinase/Foxa2 signaling pathway during DC development. SHB KD increased the expression of MHC class II and costimulatory molecules without affecting the cytokine expression of BMDCs. When co-cultured with T cells, SHB KD in BMDCs significantly induced CD4 + T-cell proliferation and the expression of Th2 cytokines, while the regulatory T cell (Treg) population was downregulated. In mouse atopic dermatitis model, mice inoculated with SHB KD DCs developed more severe symptoms of atopic dermatitis compared with mice injected with control DCs. SHB expression in DCs plays an important role in T-cell homeostasis in vivo by regulating DC-mediated Th2 polarization.

Phenotypic outcomes in Mouse and Human Foxc1 dependent Dandy-Walker cerebellar malformation suggest shared mechanisms

PubMed Central

Haldipur, Parthiv; Dang, Derek; Aldinger, Kimberly A; Janson, Olivia K; Guimiot, Fabien; Adle-Biasette, Homa; Dobyns, William B; Siebert, Joseph R; Russo, Rosa; Millen, Kathleen J

2017-01-01

FOXC1 loss contributes to Dandy-Walker malformation (DWM), a common human cerebellar malformation. Previously, we found that complete Foxc1 loss leads to aberrations in proliferation, neuronal differentiation and migration in the embryonic mouse cerebellum (Haldipur et al., 2014). We now demonstrate that hypomorphic Foxc1 mutant mice have granule and Purkinje cell abnormalities causing subsequent disruptions in postnatal cerebellar foliation and lamination. Particularly striking is the presence of a partially formed posterior lobule which echoes the posterior vermis DW 'tail sign' observed in human imaging studies. Lineage tracing experiments in Foxc1 mutant mouse cerebella indicate that aberrant migration of granule cell progenitors destined to form the posterior-most lobule causes this unique phenotype. Analyses of rare human del chr 6p25 fetal cerebella demonstrate extensive phenotypic overlap with our Foxc1 mutant mouse models, validating our DWM models and demonstrating that many key mechanisms controlling cerebellar development are likely conserved between mouse and human. DOI: http://dx.doi.org/10.7554/eLife.20898.001 PMID:28092268

In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Wei, E-mail: weiwang2@illinois.edu; Hafner, Katlyn S., E-mail: katlynhafner@gmail.com; Flaws, Jodi A., E-mail: jflaws@illinois.edu

Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestationalmore » day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in female mouse offspring.« less

A missense mutation in Grm6 reduces but does not eliminate mGluR6 expression or rod depolarizing bipolar cell function.

PubMed

Peachey, Neal S; Hasan, Nazarul; FitzMaurice, Bernard; Burrill, Samantha; Pangeni, Gobinda; Karst, Son Yong; Reinholdt, Laura; Berry, Melissa L; Strobel, Marge; Gregg, Ronald G; McCall, Maureen A; Chang, Bo

2017-08-01

GRM6 encodes the metabotropic glutamate receptor 6 (mGluR6) used by retinal depolarizing bipolar cells (DBCs). Mutations in GRM6 lead to DBC dysfunction and underlie the human condition autosomal recessive complete congenital stationary night blindness. Mouse mutants for Grm6 are important models for this condition. Here we report a new Grm6 mutant, identified in an electroretinogram (ERG) screen of mice maintained at The Jackson Laboratory. The Grm6 nob8 mouse has a reduced-amplitude b-wave component of the ERG, which reflects light-evoked DBC activity. Sequencing identified a missense mutation that converts a highly conserved methionine within the ligand binding domain to leucine (p.Met66Leu). Consistent with prior studies of Grm6 mutant mice, the laminar size and structure in the Grm6 nob8 retina were comparable to control. The Grm6 nob8 phenotype is distinguished from other Grm6 mutants that carry a null allele by a reduced but not absent ERG b-wave, decreased but present expression of mGluR6 at DBC dendritic tips, and mislocalization of mGluR6 to DBC somas. Consistent with a reduced but not absent b-wave, there were a subset of retinal ganglion cells whose responses to light onset have times to peak within the range of those in control retinas. These data indicate that the p.Met66Leu mutant mGluR6 is trafficked less than control. However, the mGluR6 that is localized to the DBC dendritic tips is able to initiate DBC signal transduction. The Grm6 nob8 mouse extends the Grm6 allelic series and will be useful for elucidating the role of mGluR6 in DBC signal transduction and in human disease. NEW & NOTEWORTHY This article describes a mouse model of the human disease complete congenital stationary night blindness in which the mutation reduces but does not eliminate GRM6 expression and bipolar cell function, a distinct phenotype from that seen in other Grm6 mouse models.

Guiding the osteogenic fate of mouse and human mesenchymal stem cells through feedback system control.

PubMed

Honda, Yoshitomo; Ding, Xianting; Mussano, Federico; Wiberg, Akira; Ho, Chih-Ming; Nishimura, Ichiro

2013-12-05

Stem cell-based disease modeling presents unique opportunities for mechanistic elucidation and therapeutic targeting. The stable induction of fate-specific differentiation is an essential prerequisite for stem cell-based strategy. Bone morphogenetic protein 2 (BMP-2) initiates receptor-regulated Smad phosphorylation, leading to the osteogenic differentiation of mesenchymal stromal/stem cells (MSC) in vitro; however, it requires supra-physiological concentrations, presenting a bottleneck problem for large-scale drug screening. Here, we report the use of a double-objective feedback system control (FSC) with a differential evolution (DE) algorithm to identify osteogenic cocktails of extrinsic factors. Cocktails containing significantly reduced doses of BMP-2 in combination with physiologically relevant doses of dexamethasone, ascorbic acid, beta-glycerophosphate, heparin, retinoic acid and vitamin D achieved accelerated in vitro mineralization of mouse and human MSC. These results provide insight into constructive approaches of FSC to determine the applicable functional and physiological environment for MSC in disease modeling, drug screening and tissue engineering.

AUTONOMIC AXONS IN THE HUMAN ENDOCRINE PANCREAS SHOW UNIQUE INNERVATION PATTERNS

PubMed Central

Rodriguez-Diaz, Rayner; Abdulreda, Midhat H.; Formoso, Alexander L.; Gans, Itai; Ricordi, Camillo; Berggren, Per-Olof; Caicedo, Alejandro

2011-01-01

SUMMARY The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, and thus impacts glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are not known, particularly in human islets. Here we demonstrate that the innervation of human islets is different from that of mouse islets and that it does not conform to existing models of autonomic control of islet function. By visualizing axons in three dimensions and quantifying axonal densities and contacts within pancreatic islets, we found that, in contrast to mouse endocrine cells, human endocrine cells are sparsely contacted by autonomic axons. Few parasympathetic cholinergic axons penetrate the human islet and the invading sympathetic fibers preferentially innervate smooth muscle cells of blood vessels located within the islet. Thus, rather than modulating endocrine cell function directly, sympathetic nerves may regulate hormone secretion in human islets by controlling local blood flow or by acting on islet regions located downstream. PMID:21723503

Apoptosis of mouse hippocampal cells induced by Taenia crassiceps metacestode factor.

PubMed

Zepeda, N; Solano, S; Copitin, N; Chávez, J L; Fernández, A M; García, F; Tato, P; Molinari, J L

2017-03-01

Seizures, headache, depression and neurological deficits are the signs and symptoms most frequently reported in human neurocysticercosis. However, the cause of the associated learning and memory deficits is unknown. Here, we used Taenia crassiceps infection in mice as a model of human cysticercosis. The effects of T. crassiceps metacestode infection or T. crassiceps metacestode factor (MF) treatment on mouse hippocampal cells were studied; control mice were included. At 45 days after infection or treatment of the mice with MF, all mice were anaesthetized and perfused transcardially with saline followed by phosphate-buffered 10% formalin. Then the brains were carefully removed. Coronal sections stained using several techniques were analysed. Extensive and significant apoptosis was found in the experimental animals, mainly in the dentate gyrus, CA1, CA2, CA3 and neighbouring regions, in comparison with the apparently intact cells from control mice (P < 0.01). These results suggest that neurological deficits, especially the learning and memory deficits, may be generated by extensive apoptosis of hippocampal cells.

Guiding the osteogenic fate of mouse and human mesenchymal stem cells through feedback system control

PubMed Central

Honda, Yoshitomo; Ding, Xianting; Mussano, Federico; Wiberg, Akira; Ho, Chih-ming; Nishimura, Ichiro

2013-01-01

Stem cell-based disease modeling presents unique opportunities for mechanistic elucidation and therapeutic targeting. The stable induction of fate-specific differentiation is an essential prerequisite for stem cell-based strategy. Bone morphogenetic protein 2 (BMP-2) initiates receptor-regulated Smad phosphorylation, leading to the osteogenic differentiation of mesenchymal stromal/stem cells (MSC) in vitro; however, it requires supra-physiological concentrations, presenting a bottleneck problem for large-scale drug screening. Here, we report the use of a double-objective feedback system control (FSC) with a differential evolution (DE) algorithm to identify osteogenic cocktails of extrinsic factors. Cocktails containing significantly reduced doses of BMP-2 in combination with physiologically relevant doses of dexamethasone, ascorbic acid, beta-glycerophosphate, heparin, retinoic acid and vitamin D achieved accelerated in vitro mineralization of mouse and human MSC. These results provide insight into constructive approaches of FSC to determine the applicable functional and physiological environment for MSC in disease modeling, drug screening and tissue engineering. PMID:24305548

Postdoctoral Fellow | Center for Cancer Research

Cancer.gov

A new Postdoctoral Fellow position is immediately available in the laboratory of Dr. Terry Yamaguchi at the National Cancer Institute. Dr.Yamaguchi's lab investigates how secreted growth factors regulate the gene regulatory networks that control the fate of embryonic and adult stem cells. Current projects focus on understanding how Wnts and Fgfs regulate the formation and differentiation of the neuromesodermal progenitor (NMP), a multipotent embryonic cell that generates the spinal cord neurons and musculoskeletal system of the body. Using a combination of mouse genetics, mouse and human embryonic stem cell in vitro differentiation, and genomic, proteomic and biochemical approaches, Dr. Yamaguchi’s lab is investigating the molecular mechanisms underlying the activity of key transcriptional determinants of NMP development.

Effect of pituitary hollow fiber units and thyroid supplementation on growth in the little mouse (41949)

NASA Technical Reports Server (NTRS)

Harkness, John E.; Hymer, W. C.; Rosenberger, James L.; Grindeland, Richard E.

1984-01-01

It is shown that the implantation of encapsulated pituitary cells into heterozygous lit/+ mice inhibited the average percentage change in weight gain as compared to controls. However, homozygous lit/lit mice receiving cell-filled capsules consistently had higher percentage weight gains than their control counterparts. It was also found that thyroid-supplemented mutant mice with pituitary cell implants had significantly higher organ and carcass weights than other mutant groups.

Local convection-enhanced delivery of an anti-CD40 agonistic monoclonal antibody induces antitumor effects in mouse glioma models

PubMed Central

Shoji, Takuhiro; Saito, Ryuta; Chonan, Masashi; Shibahara, Ichiyo; Sato, Aya; Kanamori, Masayuki; Sonoda, Yukihiko; Kondo, Toru; Ishii, Naoto; Tominaga, Teiji

2016-01-01

Background Glioblastoma is one of the most malignant brain tumors in adults and has a dismal prognosis. In a previous report, we reported that CD40, a TNF-R-related cell surface receptor, and its ligand CD40L were associated with glioma outcomes. Here we attempted to activate CD40 signaling in the tumor and determine if it exerted therapeutic efficacy. Methods CD40 expression was examined in 3 mouse glioma cell lines (GL261, NSCL61, and bRiTs-G3) and 5 human glioma cell lines (U87, U251, U373, T98, and A172). NSCL61 and bRiTs-G3, as glioma stem cells, also expressed the glioma stem cell markers MELK and CD44. In vitro, we demonstrated direct antitumor effects of an anti-CD40 agonistic monoclonal antibody (FGK45) against the cell lines. The efficacy of FGK45 was examined by local convection-enhanced delivery of the monoclonal antibody against each glioma model. Results CD40 was expressed in all mouse and human cell lines tested and was found at the cell membrane of each of the 3 mouse cell lines. FGK45 administration induced significant, direct antitumor effects in vitro. The local delivery of FGK45 significantly prolonged survival compared with controls in the NSCL61 and bRiTs-G3 models, but the effect was not significant in the GL261 model. Increases in apoptosis and CD4+ and CD8+ T cell infiltration were observed in the bRiTs-G3 model after FGK45 treatment. Conclusions Local delivery of FGK45 significantly prolonged survival in glioma stem cell models. Thus, local delivery of this monoclonal antibody is promising for immunotherapy against gliomas. PMID:26917236

Nucleosome organizations in induced pluripotent stem cells reprogrammed from somatic cells belonging to three different germ layers.

PubMed

Tao, Yu; Zheng, Weisheng; Jiang, Yonghua; Ding, Guitao; Hou, Xinfeng; Tang, Yitao; Li, Yueying; Gao, Shuai; Chang, Gang; Zhang, Xiaobai; Liu, Wenqiang; Kou, Xiaochen; Wang, Hong; Jiang, Cizhong; Gao, Shaorong

2014-12-21

Nucleosome organization determines the chromatin state, which in turn controls gene expression or silencing. Nucleosome remodeling occurs during somatic cell reprogramming, but it is still unclear to what degree the re-established nucleosome organization of induced pluripotent stem cells (iPSCs) resembles embryonic stem cells (ESCs), and whether the iPSCs inherit some residual gene expression from the parental fibroblast cells. We generated genome-wide nucleosome maps in mouse ESCs and in iPSCs reprogrammed from somatic cells belonging to three different germ layers using a secondary reprogramming system. Pairwise comparisons showed that the nucleosome organizations in the iPSCs, regardless of the iPSCs' tissue of origin, were nearly identical to the ESCs, but distinct from mouse embryonic fibroblasts (MEF). There is a canonical nucleosome arrangement of -1, nucleosome depletion region, +1, +2, +3, and so on nucleosomes around the transcription start sites of active genes whereas only a nucleosome occupies silent transcriptional units. Transcription factor binding sites possessed characteristic nucleosomal architecture, such that their access was governed by the rotational and translational settings of the nucleosome. Interestingly, the tissue-specific genes were highly expressed only in the parental somatic cells of the corresponding iPS cell line before reprogramming, but had a similar expression level in all the resultant iPSCs and ESCs. The re-established nucleosome landscape during nuclear reprogramming provides a conserved setting for accessibility of DNA sequences in mouse pluripotent stem cells. No persistent residual expression program or nucleosome positioning of the parental somatic cells that reflected their tissue of origin was passed on to the resulting mouse iPSCs.

Induction of lymphomas on implantation of human oral squamous cell carcinomas in nude mice.

PubMed

Teni, T R; Saranath, D; Mahale, A M; Pai, S A; Ahire, S D; Ingle, A D

2001-02-01

Cancer cells from five oral cancer patients and pleomorphic adenoma cells from one individual were inoculated as single cell suspension into subcutis of 30 Swiss nude mice and tail vein of additional 30 mice. Further, tumor tissue pieces from three oral cancer patients were xenografted s.c. in 18 nude mice, and 10 mice were kept as controls. In animals implanted with tumor pieces, 7/18 (39%) mice, developed squamous cell carcinoma at the site of inoculation within 8-15 days, while tumors were not observed in mice inoculated with single cell suspension, up to 60/90 days. In 8/68 (12%) mice, white foci were observed in several tissues, with hepatomegaly and splenomegaly noted in 27/68 (39%) mice. Histopathological examination of various tissues revealed presence of large cell lymphoma in several organs in 14/68 (21%) mice. No regional or distant metastasis of the implanted oral tumor cells was detected. Mice injected with cells from pleomorphic adenoma, also demonstrated large cell lymphoma in 2/10 (20%) mice, whereas none of the 10 control animals showed any gross abnormalities or microscopic abnormalities in several organs. 2/16 (12%) lymphomas exhibited positive reaction with mouse B cell antibodies illustrating the murine origin of the lymphomas, and these were immunophenotyed as B cell lymphomas. The lymphomas were also examined with mouse T cell antibodies and none reacted positively with the mouse T cell antibodies. The lymphomas also failed to react with human T cell, B cell and human Leucocyte common antigen (LCA) antibodies, indicating that the induced lymphomas were not of human origin. The tumor specimens from seven of eight oral cancer patients and the pleomorphic adenoma patient induced lymphomas in nude mice. Thus it appears that xenografting oral tumor cells into nude mice may cause induction of the murine lymphomas, and this needs further investigation.

Induction of Cervical Neoplasia in the Mouse by Herpes Simplex Virus Type 2 DNA

NASA Astrophysics Data System (ADS)

Anthony, Donald D.; Budd Wentz, W.; Reagan, James W.; Heggie, Alfred D.

1989-06-01

Induction of cervical neoplasia in the mouse cervix by herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) has been reported. The present study was done to determine if transfection with DNA of HSV-2 can induce carcinogenesis in this animal model. Genomic HSV-2 DNA was isolated from infected HEp-2 cells and separated from host cell DNA by cesium chloride density gradient centrifugation. The DNA was applied to mouse cervix for periods of 80-100 weeks. Experimental controls were treated with uninfected genomic HEp-2 cell DNA or with calf thymus DNA. Vaginal cytological preparations from all animals were examined monthly to detect epithelial abnormalities. Animals were sacrificed and histopathology studies were done when cellular changes indicative of premalignant or malignant lesions were seen on vaginal smears. Cytologic and histologic materials were coded and evaluated without knowledge of whether they were from animals treated with virus or control DNA. Premalignant and malignant cervical lesions similar to those that occur in women were detected in 61% of the histologic specimens obtained from animals exposed to HSV-2 DNA. The yield of invasive cancers was 21% in animals treated with HSV-2 DNA. No cancers were detected in mice treated with either HEp-2 or calf thymus DNA. Dysplasia was detected in only one of these control animals.

The effect of celecoxib on tumor growth in ovarian cancer cells and a genetically engineered mouse model of serous ovarian cancer.

PubMed

Suri, Anuj; Sheng, Xiugui; Schuler, Kevin M; Zhong, Yan; Han, Xiaoyun; Jones, Hannah M; Gehrig, Paola A; Zhou, Chunxiao; Bae-Jump, Victoria L

2016-06-28

Our objective was to evaluate the effect of the COX-2 inhibitor, celecoxib, on (1) proliferation and apoptosis in human ovarian cancer cell lines and primary cultures of ovarian cancer cells, and (2) inhibition of tumor growth in a genetically engineered mouse model of serous ovarian cancer under obese and non-obese conditions. Celecoxib inhibited cell proliferation in three ovarian cancer cell lines and five primary cultures of human ovarian cancer after 72 hours of exposure. Treatment with celecoxib resulted in G1 cell cycle arrest, induction of apoptosis, inhibition of cellular adhesion and invasion and reduction of expression of hTERT mRNA and COX-2 protein in all of the ovarian cancer cell lines. In the KpB mice fed a high fat diet (obese) and treated with celecoxib, tumor weight decreased by 66% when compared with control animals. Among KpB mice fed a low fat diet (non-obese), tumor weight decreased by 46% after treatment with celecoxib. In the ovarian tumors from obese and non-obese KpB mice, treatment with celecoxib as compared to control resulted in decreased proliferation, increased apoptosis and reduced COX-2 and MMP9 protein expression, as assessed by immunohistochemistry. Celecoxib strongly decreased the serum level of VEGF and blood vessel density in the tumors from the KpB ovarian cancer mouse model under obese and non-obese conditions. This work suggests that celecoxib may be a novel chemotherapeutic agent for ovarian cancer prevention and treatment and be potentially beneficial in both obese and non-obese women.

The effect of celecoxib on tumor growth in ovarian cancer cells and a genetically engineered mouse model of serous ovarian cancer

PubMed Central

Suri, Anuj; Sheng, Xiugui; Schuler, Kevin M.; Zhong, Yan; Han, Xiaoyun; Jones, Hannah M.; Gehrig, Paola A.; Zhou, Chunxiao; Bae-Jump, Victoria L.

2016-01-01

Our objective was to evaluate the effect of the COX-2 inhibitor, celecoxib, on (1) proliferation and apoptosis in human ovarian cancer cell lines and primary cultures of ovarian cancer cells, and (2) inhibition of tumor growth in a genetically engineered mouse model of serous ovarian cancer under obese and non-obese conditions. Celecoxib inhibited cell proliferation in three ovarian cancer cell lines and five primary cultures of human ovarian cancer after 72 hours of exposure. Treatment with celecoxib resulted in G1 cell cycle arrest, induction of apoptosis, inhibition of cellular adhesion and invasion and reduction of expression of hTERT mRNA and COX-2 protein in all of the ovarian cancer cell lines. In the KpB mice fed a high fat diet (obese) and treated with celecoxib, tumor weight decreased by 66% when compared with control animals. Among KpB mice fed a low fat diet (non-obese), tumor weight decreased by 46% after treatment with celecoxib. In the ovarian tumors from obese and non-obese KpB mice, treatment with celecoxib as compared to control resulted in decreased proliferation, increased apoptosis and reduced COX-2 and MMP9 protein expression, as assessed by immunohistochemistry. Celecoxib strongly decreased the serum level of VEGF and blood vessel density in the tumors from the KpB ovarian cancer mouse model under obese and non-obese conditions. This work suggests that celecoxib may be a novel chemotherapeutic agent for ovarian cancer prevention and treatment and be potentially beneficial in both obese and non-obese women. PMID:27074576

Huntingtin Acts Non Cell-Autonomously on Hippocampal Neurogenesis and Controls Anxiety-Related Behaviors in Adult Mouse

PubMed Central

Pla, Patrick; Orvoen, Sophie; Benstaali, Caroline; Dodier, Sophie; Gardier, Alain M.; David, Denis J.; Humbert, Sandrine; Saudou, Frédéric

2013-01-01

Huntington’s disease (HD) is a fatal neurodegenerative disease, characterized by motor defects and psychiatric symptoms, including mood disorders such as anxiety and depression. HD is caused by an abnormal polyglutamine (polyQ) expansion in the huntingtin (HTT) protein. The development and analysis of various mouse models that express pathogenic polyQ-HTT revealed a link between mutant HTT and the development of anxio-depressive behaviors and various hippocampal neurogenesis defects. However, it is unclear whether such phenotype is linked to alteration of HTT wild-type function in adults. Here, we report the analysis of a new mouse model in which HTT is inducibly deleted from adult mature cortical and hippocampal neurons using the CreERT2/Lox system. These mice present defects in both the survival and the dendritic arborization of hippocampal newborn neurons. Our data suggest that these non-cell autonomous effects are linked to defects in both BDNF transport and release upon HTT silencing in hippocampal neurons, and in BDNF/TrkB signaling. The controlled deletion of HTT also had anxiogenic-like effects. Our results implicate endogenous wild-type HTT in adult hippocampal neurogenesis and in the control of mood disorders. PMID:24019939

Effect of porcine circovirus type 2 (PCV2) on the function of splenic CD11c+ dendritic cells in mice.

PubMed

Wang, Xiaobo; Chen, Ligong; Yuan, Wanzhe; Li, Yanqin; Li, Limin; Li, Tanqing; Li, Huanrong; Song, Qinye

2017-05-01

Porcine circovirus-associated disease (PCVAD) caused by porcine circovirus type 2 (PCV2) is an important disease in the global pig industry. Dendritic cells (DCs) are the primary immune cells capable of initiating adaptive immune responses as well as major target cells of PCV2. To determine whether PCV2 affects the immune functions of DCs, we evaluated the expression of endocytosis and co-stimulatory molecules on DCs (CD11c + ) from PCV2-infected mouse spleen by flow cytometry (FCM). We also analyzed the main cytokines secreted by DCs (CD11c + ) and activation of CD4 + and CD8 + T cells by DCs (CD11c + ) through measurement of cytokine secretion, using ELISA. Compared with control mice, PCV2 did not affect the endocytic activity of DCs but it significantly enhanced TNF-α secretion and markedly decreased IFN-α secretion. Subsets of CD40 + , MHCII + CD40 + and CD137L + CD86 + DCs did not increase obviously, but MHCII + CD40 - and CD137L - CD80 + /CD86 + DCs increased significantly in PCV2-infected mouse spleen. Under the stimulation of DCs from PCV2-infected mouse, secretion of IFN-γ by CD4 + and CD8 + T cells and of IL-12 by CD8 + T cells was significantly lower than in control mice, while secretion of IL-4 by CD4 + T cells was remarkably higher. These results indicate that PCV2 modulates cytokine secretion and co-stimulatory molecule expression of DCs, and alters activation of CD4 + and CD8 + T cells by DCs. The immunomodulatory effects of PCV2 on DCs might be related to the host's immune dysfunction and persistent infection with this virus.

Zscan4 is regulated by PI3-kinase and DNA-damaging agents and directly interacts with the transcriptional repressors LSD1 and CtBP2 in mouse embryonic stem cells.

PubMed

Storm, Michael P; Kumpfmueller, Benjamin; Bone, Heather K; Buchholz, Michael; Sanchez Ripoll, Yolanda; Chaudhuri, Julian B; Niwa, Hitoshi; Tosh, David; Welham, Melanie J

2014-01-01

The Zscan4 family of genes, encoding SCAN-domain and zinc finger-containing proteins, has been implicated in the control of early mammalian embryogenesis as well as the regulation of pluripotency and maintenance of genome integrity in mouse embryonic stem cells. However, many features of this enigmatic family of genes are poorly understood. Here we show that undifferentiated mouse embryonic stem cell (ESC) lines simultaneously express multiple members of the Zscan4 gene family, with Zscan4c, Zscan4f and Zscan4-ps2 consistently being the most abundant. Despite this, between only 0.1 and 0.7% of undifferentiated mouse pluripotent stem cells express Zscan4 protein at a given time, consistent with a very restricted pattern of Zscan4 transcripts reported previously. Herein we demonstrate that Zscan4 expression is regulated by the p110α catalytic isoform of phosphoinositide 3-kinases and is induced following exposure to a sub-class of DNA-damage-inducing agents, including Zeocin and Cisplatin. Furthermore, we observe that Zscan4 protein expression peaks during the G2 phase of the cell cycle, suggesting that it may play a critical role at this checkpoint. Studies with GAL4-fusion proteins suggest a role for Zscan4 in transcriptional regulation, further supported by the fact that protein interaction analyses demonstrate that Zscan4 interacts with both LSD1 and CtBP2 in ESC nuclei. This study advances and extends our understanding of Zscan4 expression, regulation and mechanism of action. Based on our data we propose that Zscan4 may regulate gene transcription in mouse ES cells through interaction with LSD1 and CtBP2.

Zscan4 Is Regulated by PI3-Kinase and DNA-Damaging Agents and Directly Interacts with the Transcriptional Repressors LSD1 and CtBP2 in Mouse Embryonic Stem Cells

PubMed Central

Bone, Heather K.; Buchholz, Michael; Sanchez Ripoll, Yolanda; Chaudhuri, Julian B.; Niwa, Hitoshi; Tosh, David; Welham, Melanie J.

2014-01-01

The Zscan4 family of genes, encoding SCAN-domain and zinc finger-containing proteins, has been implicated in the control of early mammalian embryogenesis as well as the regulation of pluripotency and maintenance of genome integrity in mouse embryonic stem cells. However, many features of this enigmatic family of genes are poorly understood. Here we show that undifferentiated mouse embryonic stem cell (ESC) lines simultaneously express multiple members of the Zscan4 gene family, with Zscan4c, Zscan4f and Zscan4-ps2 consistently being the most abundant. Despite this, between only 0.1 and 0.7% of undifferentiated mouse pluripotent stem cells express Zscan4 protein at a given time, consistent with a very restricted pattern of Zscan4 transcripts reported previously. Herein we demonstrate that Zscan4 expression is regulated by the p110α catalytic isoform of phosphoinositide 3-kinases and is induced following exposure to a sub-class of DNA-damage-inducing agents, including Zeocin and Cisplatin. Furthermore, we observe that Zscan4 protein expression peaks during the G2 phase of the cell cycle, suggesting that it may play a critical role at this checkpoint. Studies with GAL4-fusion proteins suggest a role for Zscan4 in transcriptional regulation, further supported by the fact that protein interaction analyses demonstrate that Zscan4 interacts with both LSD1 and CtBP2 in ESC nuclei. This study advances and extends our understanding of Zscan4 expression, regulation and mechanism of action. Based on our data we propose that Zscan4 may regulate gene transcription in mouse ES cells through interaction with LSD1 and CtBP2. PMID:24594919

Automated Cell Detection and Morphometry on Growth Plate Images of Mouse Bone

PubMed Central

Ascenzi, Maria-Grazia; Du, Xia; Harding, James I; Beylerian, Emily N; de Silva, Brian M; Gross, Ben J; Kastein, Hannah K; Wang, Weiguang; Lyons, Karen M; Schaeffer, Hayden

2014-01-01

Microscopy imaging of mouse growth plates is extensively used in biology to understand the effect of specific molecules on various stages of normal bone development and on bone disease. Until now, such image analysis has been conducted by manual detection. In fact, when existing automated detection techniques were applied, morphological variations across the growth plate and heterogeneity of image background color, including the faint presence of cells (chondrocytes) located deeper in tissue away from the image’s plane of focus, and lack of cell-specific features, interfered with identification of cell. We propose the first method of automated detection and morphometry applicable to images of cells in the growth plate of long bone. Through ad hoc sequential application of the Retinex method, anisotropic diffusion and thresholding, our new cell detection algorithm (CDA) addresses these challenges on bright-field microscopy images of mouse growth plates. Five parameters, chosen by the user in respect of image characteristics, regulate our CDA. Our results demonstrate effectiveness of the proposed numerical method relative to manual methods. Our CDA confirms previously established results regarding chondrocytes’ number, area, orientation, height and shape of normal growth plates. Our CDA also confirms differences previously found between the genetic mutated mouse Smad1/5CKO and its control mouse on fluorescence images. The CDA aims to aid biomedical research by increasing efficiency and consistency of data collection regarding arrangement and characteristics of chondrocytes. Our results suggest that automated extraction of data from microscopy imaging of growth plates can assist in unlocking information on normal and pathological development, key to the underlying biological mechanisms of bone growth. PMID:25525552

Decreased adult hippocampal neurogenesis in the PDAPP mouse model of Alzheimer's disease.

PubMed

Donovan, Michael H; Yazdani, Umar; Norris, Rebekah D; Games, Dora; German, Dwight C; Eisch, Amelia J

2006-03-01

Abnormal subgranular zone (SGZ) neurogenesis is proposed to contribute to Alzheimer's disease (AD)-related decreases in hippocampal function. Our goal was to examine hippocampal neurogenesis in the PDAPP mouse, a model of AD with age-dependent accumulation of amyloid-beta(42) (Abeta(42))-containing plaques that is well studied with regard to AD therapies. A secondary goal was to determine whether altered neurogenesis in the PDAPP mouse is associated with abnormal maturation or number of mature cells. A tertiary goal was to provide insight into why hippocampal neurogenesis appears to be increased in AD post-mortem tissue and decreased in most AD mouse models. We report an age-dependent decrease in SGZ proliferation in homozygous PDAPP mice. At 1 year of age, PDAPP mice also had new dentate gyrus granule neurons with abnormal maturation and fewer dying cells relative to control mice. In contrast to decreased SGZ cell birth, PDAPP mice had increased birth of immature neurons in the outer portion of the granule cell layer (oGCL), providing insight into why some studies link AD with increased neurogenesis. However, these ectopic oGCL cells were still rare compared with SGZ proliferating cells, emphasizing that the primary characteristic of PDAPP mice is decreased neurogenesis. The decrease in SGZ neurogenesis was not associated with an age-dependent loss of dentate granule neurons. The altered neurogenesis in the PDAPP mouse may contribute to the age-related cognitive deficits reported in this model of AD and may be a useful adjunct target for assessing the impact of AD therapies. J. Comp. Neurol. 495:70-83, 2006. (c) 2006 Wiley-Liss, Inc.

Phosphoinositide 3-kinase gamma regulates airway smooth muscle contraction by modulating calcium oscillations.

PubMed

Jiang, Haihong; Abel, Peter W; Toews, Myron L; Deng, Caishu; Casale, Thomas B; Xie, Yan; Tu, Yaping

2010-09-01

Phosphoinositide 3-kinase gamma (PI3Kgamma) has been implicated in the pathogenesis of asthma, but its mechanism has been considered indirect, through release of inflammatory cell mediators. Because airway smooth muscle (ASM) contractile hyper-responsiveness plays a critical role in asthma, the aim of the present study was to determine whether PI3Kgamma can directly regulate contractility of ASM. Immunohistochemistry staining indicated expression of PI3Kgamma protein in ASM cells of mouse trachea and lung, which was confirmed by Western blot analysis in isolated mouse tracheal ASM cells. PI3Kgamma inhibitor II inhibited acetylcholine (ACh)-stimulated airway contraction of cultured precision-cut mouse lung slices in a dose-dependent manner with 75% inhibition at 10 muM. In contrast, inhibitors of PI3Kalpha, PI3Kbeta, or PI3Kdelta, at concentrations 40-fold higher than their reported IC(50) values for their primary targets, had no effect. It is noteworthy that airways in lung slices pretreated with PI3Kgamma inhibitor II still exhibited an ACh-induced initial contraction, but the sustained contraction was significantly reduced. Furthermore, the PI3Kgamma-selective inhibitor had a small inhibitory effect on the ACh-stimulated initial Ca(2+) transient in ASM cells of mouse lung slices or isolated mouse ASM cells but significantly attenuated the sustained Ca(2+) oscillations that are critical for sustained airway contraction. This report is the first to show that PI3Kgamma directly controls contractility of airways through regulation of Ca(2+) oscillations in ASM cells. Thus, in addition to effects on airway inflammation, PI3Kgamma inhibitors may also exert direct effects on the airway contraction that contribute to pathologic airway hyper-responsiveness.

Phosphoinositide 3-Kinase γ Regulates Airway Smooth Muscle Contraction by Modulating Calcium Oscillations

PubMed Central

Jiang, Haihong; Abel, Peter W.; Toews, Myron L.; Deng, Caishu; Casale, Thomas B.; Xie, Yan

2010-01-01

Phosphoinositide 3-kinase γ (PI3Kγ) has been implicated in the pathogenesis of asthma, but its mechanism has been considered indirect, through release of inflammatory cell mediators. Because airway smooth muscle (ASM) contractile hyper-responsiveness plays a critical role in asthma, the aim of the present study was to determine whether PI3Kγ can directly regulate contractility of ASM. Immunohistochemistry staining indicated expression of PI3Kγ protein in ASM cells of mouse trachea and lung, which was confirmed by Western blot analysis in isolated mouse tracheal ASM cells. PI3Kγ inhibitor II inhibited acetylcholine (ACh)-stimulated airway contraction of cultured precision-cut mouse lung slices in a dose-dependent manner with 75% inhibition at 10 μM. In contrast, inhibitors of PI3Kα, PI3Kβ, or PI3Kδ, at concentrations 40-fold higher than their reported IC50 values for their primary targets, had no effect. It is noteworthy that airways in lung slices pretreated with PI3Kγ inhibitor II still exhibited an ACh-induced initial contraction, but the sustained contraction was significantly reduced. Furthermore, the PI3Kγ-selective inhibitor had a small inhibitory effect on the ACh-stimulated initial Ca2+ transient in ASM cells of mouse lung slices or isolated mouse ASM cells but significantly attenuated the sustained Ca2+ oscillations that are critical for sustained airway contraction. This report is the first to show that PI3Kγ directly controls contractility of airways through regulation of Ca2+ oscillations in ASM cells. Thus, in addition to effects on airway inflammation, PI3Kγ inhibitors may also exert direct effects on the airway contraction that contribute to pathologic airway hyper-responsiveness. PMID:20501633

Novel insights into embryonic stem cell self-renewal revealed through comparative human and mouse systems biology networks.

PubMed

Dowell, Karen G; Simons, Allen K; Bai, Hao; Kell, Braden; Wang, Zack Z; Yun, Kyuson; Hibbs, Matthew A

2014-05-01

Embryonic stem cells (ESCs), characterized by their ability to both self-renew and differentiate into multiple cell lineages, are a powerful model for biomedical research and developmental biology. Human and mouse ESCs share many features, yet have distinctive aspects, including fundamental differences in the signaling pathways and cell cycle controls that support self-renewal. Here, we explore the molecular basis of human ESC self-renewal using Bayesian network machine learning to integrate cell-type-specific, high-throughput data for gene function discovery. We integrated high-throughput ESC data from 83 human studies (~1.8 million data points collected under 1,100 conditions) and 62 mouse studies (~2.4 million data points collected under 1,085 conditions) into separate human and mouse predictive networks focused on ESC self-renewal to analyze shared and distinct functional relationships among protein-coding gene orthologs. Computational evaluations show that these networks are highly accurate, literature validation confirms their biological relevance, and reverse transcriptase polymerase chain reaction (RT-PCR) validation supports our predictions. Our results reflect the importance of key regulatory genes known to be strongly associated with self-renewal and pluripotency in both species (e.g., POU5F1, SOX2, and NANOG), identify metabolic differences between species (e.g., threonine metabolism), clarify differences between human and mouse ESC developmental signaling pathways (e.g., leukemia inhibitory factor (LIF)-activated JAK/STAT in mouse; NODAL/ACTIVIN-A-activated fibroblast growth factor in human), and reveal many novel genes and pathways predicted to be functionally associated with self-renewal in each species. These interactive networks are available online at www.StemSight.org for stem cell researchers to develop new hypotheses, discover potential mechanisms involving sparsely annotated genes, and prioritize genes of interest for experimental validation. © 2013 AlphaMed Press.

Derivation, propagation and differentiation of human embryonic stem cells.

PubMed

Conley, Brock J; Young, Julia C; Trounson, Alan O; Mollard, Richard

2004-04-01

Embryonic stem (ES) cells are in vitro cultivated pluripotent cells derived from the inner cell mass (ICM) of the embryonic blastocyst. Attesting to their pluripotency, ES cells can be differentiated into representative derivatives of all three embryonic germ layers (endoderm, ectoderm and mesoderm) both in vitro and in vivo. Although mouse ES cells have been studied for many years, human ES cells have only more recently been derived and successfully propagated. Many biochemical differences and culture requirements between mouse and human ES cells have been described, yet despite these differences the study of murine ES cells has provided important insights into methodologies aimed at generating a greater and more in depth understanding of human ES cell biology. One common feature of both mouse and human ES cells is their capacity to undergo controlled differentiation into spheroid structures termed embryoid bodies (EBs). EBs recapitulate several aspects of early development, displaying regional-specific differentiation programs into derivatives of all three embryonic germ layers. For this reason, EB formation has been utilised as an initial step in a wide range of studies aimed at differentiating both mouse and human ES cells into a specific and desired cell type. Recent reports utilising specific growth factor combinations and cell-cell induction systems have provided alternative strategies for the directed differentiation of cells into a desired lineage. According to each one of these strategies, however, a relatively high cell lineage heterogeneity remains, necessitating subsequent purification steps including mechanical dissection, selective media or fluorescent or magnetic activated cell sorting (FACS and MACS, respectively). In the future, the ability to specifically direct differentiation of human ES cells at 100% efficiency into a desired lineage will allow us to fully explore the potential of these cells in the analysis of early human development, drug discovery, drug testing and repair of damaged or diseased tissues via transplantation.

Abrin Toxicity and Bioavailability after Temperature and pH Treatment.

PubMed

Tam, Christina C; Henderson, Thomas D; Stanker, Larry H; He, Xiaohua; Cheng, Luisa W

2017-10-13

Abrin, one of most potent toxins known to man, is derived from the rosary pea (jequirity pea), Abrus precatorius and is a potential bioterror weapon. The temperature and pH stability of abrin was evaluated with an in vitro cell free translation (CFT) assay, a Vero cell culture cytotoxicity assay, and an in vivo mouse bioassay. pH treatment of abrin had no detrimental effect on its stability and toxicity as seen either in vitro or in vivo. Abrin exposure to increasing temperatures did not completely abrogate protein translation. In both the cell culture cytotoxicity model and the mouse bioassay, abrin's toxic effects were completely abrogated if the toxin was exposed to temperatures of 74 °C or higher. In the cell culture model, 63 °C-treated abrin had a 30% reduction in cytotoxicity which was validated in the in vivo mouse bioassay with all mice dying but with a slight time-to-death delay as compared to the non-treated abrin control. Since temperature inactivation did not affect abrin's ability to inhibit protein synthesis (A-chain), we hypothesize that high temperature treatment affected abrin's ability to bind to cellular receptors (affecting B-chain). Our results confirm the absolute need to validate in vitro cytotoxicity assays with in vivo mouse bioassays.

Abrin Toxicity and Bioavailability after Temperature and pH Treatment

PubMed Central

Tam, Christina C.; Henderson, Thomas D.; Stanker, Larry H.; He, Xiaohua; Cheng, Luisa W.

2017-01-01

Abrin, one of most potent toxins known to man, is derived from the rosary pea (jequirity pea), Abrus precatorius and is a potential bioterror weapon. The temperature and pH stability of abrin was evaluated with an in vitro cell free translation (CFT) assay, a Vero cell culture cytotoxicity assay, and an in vivo mouse bioassay. pH treatment of abrin had no detrimental effect on its stability and toxicity as seen either in vitro or in vivo. Abrin exposure to increasing temperatures did not completely abrogate protein translation. In both the cell culture cytotoxicity model and the mouse bioassay, abrin’s toxic effects were completely abrogated if the toxin was exposed to temperatures of 74 °C or higher. In the cell culture model, 63 °C-treated abrin had a 30% reduction in cytotoxicity which was validated in the in vivo mouse bioassay with all mice dying but with a slight time-to-death delay as compared to the non-treated abrin control. Since temperature inactivation did not affect abrin’s ability to inhibit protein synthesis (A-chain), we hypothesize that high temperature treatment affected abrin’s ability to bind to cellular receptors (affecting B-chain). Our results confirm the absolute need to validate in vitro cytotoxicity assays with in vivo mouse bioassays. PMID:29027937

Fine regulation of RhoA and Rock is required for skeletal muscle differentiation.

PubMed

Castellani, Loriana; Salvati, Erica; Alemà, Stefano; Falcone, Germana

2006-06-02

The RhoA GTPase controls a variety of cell functions such as cell motility, cell growth, and gene expression. Previous studies suggested that RhoA mediates signaling inputs that promote skeletal myogenic differentiation. We show here that levels and activity of RhoA protein are down-regulated in both primary avian myoblasts and mouse satellite cells undergoing differentiation, suggesting that a fine regulation of this GTPase is required. In addition, ectopic expression of activated RhoA in primary quail myocytes, but not in mouse myocytes, inhibits accumulation of muscle-specific proteins and cell fusion. By disrupting RhoA signaling with specific inhibitors, we have shown that this GTPase, although required for cell identity in proliferating myoblasts, is not essential for commitment to terminal differentiation and muscle gene expression. Ectopic expression of an activated form of its downstream effector, Rock, impairs differentiation of both avian and mouse myoblasts. Conversely, Rock inhibition with specific inhibitors and small interfering RNA-mediated gene silencing leads to accelerated progression in the lineage and enhanced cell fusion, underscoring a negative regulatory function of Rock in myogenesis. Finally, we have reported that Rock acts independently from RhoA in preventing myoblast exit from the cell cycle and commitment to differentiation and may receive signaling inputs from Raf-1 kinase.

Single Targeted Exon Mutation Creates a True Congenic Mouse for Competitive Hematopoietic Stem Cell Transplantation: The C57BL/6-CD45.1(STEM) Mouse.

PubMed

Mercier, Francois E; Sykes, David B; Scadden, David T

2016-06-14

Defining the molecular regulators of hematopoietic stem and progenitor cells (HSPCs) requires in vivo functional analyses. Competitive bone marrow transplants (BMTs) compare control and test HSPCs to demonstrate the functional role of a genetic change or chemical perturbation. Competitive BMT is enabled by antibodies that specifically recognize hematopoietic cells from congenic mouse strains due to variants of the cell surface protein CD45, designated CD45.1 and CD45.2. The current congenic competitor strain, B6.SJL-Ptprc(a) Pepc(b)/BoyJ (CD45.1), has a substantial inherent disadvantage in competition against the C57BL/6 (CD45.2) strain, confounding experimental interpretation. Despite backcrossing, the congenic interval over which the B6.SJL-Ptprc(a) Pepc(b)/BoyJ strain differs is almost 40 Mb encoding ∼300 genes. Here, we demonstrate that a single amino acid change determines the CD45.1 epitope. Further, we report on the single targeted exon mutant (STEM) mouse strain, CD45.1(STEM), which is functionally equivalent to CD45.2 cells in competitive BMT. This strain will permit the precise definition of functional roles for candidate genes using in vivo HSPC assays. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Nuclear localized protein-1 (Nulp1) increases cell death of human osteosarcoma cells and binds the X-linked inhibitor of apoptosis protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steen, Hakan; Lindholm, Dan; Minerva Institute for Medical Research, Biomedicum Helsinki, Helsinki

2008-02-08

Nuclear localized protein-1 (Nulp1) is a recently identified gene expressed in mouse and human tissues particularly during embryonic development. Nulp1 belongs to the family of basic helix-loop-helix (bHLH) proteins that are important in development. The precise function of Nulp1 in cells is however not known. We observed that overexpression of Nulp1 induces a large increase in cell death of human osteosarcoma Saos2 cells with DNA fragmentation. In mouse N2A neuroblastoma cells Nulp1 affected cell proliferation and sensitized cells towards death induced by staurosporine. Staining using a novel antibody localized Nulp1 mainly to the cell nucleus and to some extent tomore » the cytoplasm. Nulp1 binds the X-linked inhibitor of apoptosis protein (XIAP) and this interaction was increased during cell death. These results indicate that Nulp1 plays a role in cell death control and may influence tumor growth.« less

Knockdown of EphB1 receptor decreases medulloblastoma cell growth and migration and increases cellular radiosensitization

PubMed Central

Timofeeva, Olga; Pasquale, Elena B.; Hirsch, Kellen; MacDonald, Tobey J.; Dritschilo, Anatoly; Lee, Yi Chien; Henkemeyer, Mark; Rood, Brian; Jung, Mira; Wang, Xiao-Jing; Kool, Marcel

2015-01-01

The expression of members of the Eph family of receptor tyrosine kinases and their ephrin ligands is frequently dysregulated in medulloblastomas. We assessed the expression and functional role of EphB1 in medulloblastoma cell lines and engineered mouse models. mRNA and protein expression profiling showed expression of EphB1 receptor in the human medulloblastoma cell lines DAOY and UW228. EphB1 downregulation reduced cell growth and viability, decreased the expression of important cell cycle regulators, and increased the percentage of cells in G1 phase of the cell cycle. It also modulated the expression of proliferation, and cell survival markers. In addition, EphB1 knockdown in DAOY cells resulted in significant decrease in migration, which correlated with decreased β1-integrin expression and levels of phosphorylated Src. Furthermore, EphB1 knockdown enhanced cellular radiosensitization of medulloblastoma cells in culture and in a genetically engineered mouse medulloblastoma model. Using genetically engineered mouse models, we established that genetic loss of EphB1 resulted in a significant delay in tumor recurrence following irradiation compared to EphB1-expressing control tumors. Taken together, our findings establish that EphB1 plays a key role in medulloblastoma cell growth, viability, migration, and radiation sensitivity, making EphB1 a promising therapeutic target. PMID:25879388

Knockdown of EphB1 receptor decreases medulloblastoma cell growth and migration and increases cellular radiosensitization.

PubMed

Bhatia, Shilpa; Baig, Nimrah A; Timofeeva, Olga; Pasquale, Elena B; Hirsch, Kellen; MacDonald, Tobey J; Dritschilo, Anatoly; Lee, Yi Chien; Henkemeyer, Mark; Rood, Brian; Jung, Mira; Wang, Xiao-Jing; Kool, Marcel; Rodriguez, Olga; Albanese, Chris; Karam, Sana D

2015-04-20

The expression of members of the Eph family of receptor tyrosine kinases and their ephrin ligands is frequently dysregulated in medulloblastomas. We assessed the expression and functional role of EphB1 in medulloblastoma cell lines and engineered mouse models. mRNA and protein expression profiling showed expression of EphB1 receptor in the human medulloblastoma cell lines DAOY and UW228. EphB1 downregulation reduced cell growth and viability, decreased the expression of important cell cycle regulators, and increased the percentage of cells in G1 phase of the cell cycle. It also modulated the expression of proliferation, and cell survival markers. In addition, EphB1 knockdown in DAOY cells resulted in significant decrease in migration, which correlated with decreased β1-integrin expression and levels of phosphorylated Src. Furthermore, EphB1 knockdown enhanced cellular radiosensitization of medulloblastoma cells in culture and in a genetically engineered mouse medulloblastoma model. Using genetically engineered mouse models, we established that genetic loss of EphB1 resulted in a significant delay in tumor recurrence following irradiation compared to EphB1-expressing control tumors. Taken together, our findings establish that EphB1 plays a key role in medulloblastoma cell growth, viability, migration, and radiation sensitivity, making EphB1 a promising therapeutic target.

A novel homologous model for gene therapy of dwarfism by non-viral transfer of the mouse growth hormone gene into immunocompetent dwarf mice.

PubMed

Cecchi, Claudia R; Higuti, Eliza; Oliveira, Nelio A J; Lima, Eliana R; Jakobsen, Maria; Dagnaes-Hansen, Frederick; Gissel, Hanne; Aagaard, Lars; Jensen, Thomas G; Jorge, Alexander A L; Bartolini, Paolo; Peroni, Cibele N

2014-02-01

The possibilities for non-viral GH gene therapy are studied in immunocompetent dwarf mice (lit/lit). As expression vector we used a plasmid previously employed in immunodeficient dwarf mice (pUBI-hGH-gDNA) by replacing the human GH gene with the genomic sequence of mouse-GH DNA (pUBI-mGH-gDNA). HEK-293 human cells transfected with pUBI-mGH-gDNA produced 3.0 µg mGH/10(6) cells/day compared to 3.7 µg hGH/10(6) cells/day for pUBIhGH- gDNA transfected cells. The weight of lit/lit mice treated with the same two plasmids (50 µg DNA/mouse) by electrotransfer into the quadriceps muscle was followed for 3 months. The weight increase up to 15 days for mGH, hGH and saline treated mice were 0.130, 0.112 and 0.027 g/mouse/day. Most sera from hGH-treated mice contained anti-hGH antibodies already on day 15, with the highest titers on day 45, while no significant anti-mGH antibodies were observed in mGH-treated mice. At the end of 3 months, the weight increase for mGH-treated mice was 34.3%, while the nose-to-tail and femur lengths increased 9.5% and 24.3%. Mouse-GH and hGH circulating levels were 4-5 ng/mL 15 days after treatment, versus control levels of ~0.7 ng GH/mL (P<0.001). In mGH-treated mice, mIGF-I determined on days 15, 45 and 94 were 1.5- to 3-fold higher than the control and 1.2- to 1.6-fold higher than hGH-treated mice. The described homologous model represents an important progress forming the basis for preclinical testing of non-viral gene therapy for GH deficiency.

Optimal voltage stimulation parameters for network-mediated responses in wild type and rd10 mouse retinal ganglion cells

NASA Astrophysics Data System (ADS)

Jalligampala, Archana; Sekhar, Sudarshan; Zrenner, Eberhart; Rathbun, Daniel L.

2017-04-01

To further improve the quality of visual percepts elicited by microelectronic retinal prosthetics, substantial efforts have been made to understand how retinal neurons respond to electrical stimulation. It is generally assumed that a sufficiently strong stimulus will recruit most retinal neurons. However, recent evidence has shown that the responses of some retinal neurons decrease with excessively strong stimuli (a non-monotonic response function). Therefore, it is necessary to identify stimuli that can be used to activate the majority of retinal neurons even when such non-monotonic cells are part of the neuronal population. Taking these non-monotonic responses into consideration, we establish the optimal voltage stimulation parameters (amplitude, duration, and polarity) for epiretinal stimulation of network-mediated (indirect) ganglion cell responses. We recorded responses from 3958 mouse retinal ganglion cells (RGCs) in both healthy (wild type, WT) and a degenerating (rd10) mouse model of retinitis pigmentosa—using flat-mounted retina on a microelectrode array. Rectangular monophasic voltage-controlled pulses were presented with varying voltage, duration, and polarity. We found that in 4-5 weeks old rd10 mice the RGC thresholds were comparable to those of WT. There was a marked response variability among mouse RGCs. To account for this variability, we interpolated the percentage of RGCs activated at each point in the voltage-polarity-duration stimulus space, thus identifying the optimal voltage-controlled pulse (-2.4 V, 0.88 ms). The identified optimal voltage pulse can activate at least 65% of potentially responsive RGCs in both mouse strains. Furthermore, this pulse is well within the range of stimuli demonstrated to be safe and effective for retinal implant patients. Such optimized stimuli and the underlying method used to identify them support a high yield of responsive RGCs and will serve as an effective guideline for future in vitro investigations of retinal electrostimulation by establishing standard stimuli for each unique experimental condition.

The effect of space flight on monoclonal antibody synthesis in a hybridoma mouse cell line

NASA Technical Reports Server (NTRS)

Smiley, S. A.; Gillock, E. T.; Black, M. C.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

1997-01-01

The hybridoma cell line, 3G10G5, producing a monoclonal antibody to the major capsid protein VP1 from the avian polyomavirus budgerigar fledgling disease virus, was produced from a Balb/C mouse. This cell line was used to test the effects of microgravity on cellular processes, specifically protein synthesis. A time course study utilizing incorporation of [35S]methionine into newly synthesized monoclonal antibody was performed on STS-77. After 5.5 days, it was observed that cell counts for the samples exposed to microgravity were lower than those of ground-based samples. However, radiolabel incorporation of the synthesized monoclonal antibody was similar in both orbiter and ground control samples. Overall, microgravity does not seem to have an effect on this cell line's ability to synthesize IgG protein.

Behavioral Analysis of Genetically Modified Mice Indicates Essential Roles of Neurosteroidal Estrogen

PubMed Central

Honda, Shin-Ichiro; Wakatsuki, Toru; Harada, Nobuhiro

2011-01-01

Aromatase in the mouse brain is expressed only in the nerve cells of specific brain regions with a transient peak during the neonatal period when sexual behaviors become organized. The aromatase-knockout (ArKO) mouse, generated to shed light on the physiological functions of estrogen in the brain, exhibited various abnormal behaviors, concomitant with undetectable estrogen and increased androgen in the blood. To further elucidate the effects of neurosteroidal estrogens on behavioral phenotypes, we first prepared an brain-specific aromatase transgenic (bsArTG) mouse by introduction of a human aromatase transgene controlled under a −6.5 kb upstream region of the brain-specific promoter of the mouse aromatase gene into fertilized mouse eggs, because the −6.5 kb promoter region was previously shown to contain the minimal essential element responsible for brain-specific spatiotemporal expression. Then, an ArKO mouse expressing the human aromatase only in the brain was generated by crossing the bsArTG mouse with the ArKO mouse. The resulting mice (ArKO/bsArTG mice) nearly recovered from abnormal sexual, aggressive, and locomotive (exploratory) behaviors, in spite of having almost the same serum levels of estrogen and androgen as the adult ArKO mouse. These results suggest that estrogens locally synthesized in the specific neurons of the perinatal mouse brain directly act on the neurons and play crucial roles in the organization of neuronal networks participating in the control of sexual, aggressive, and locomotive (exploratory) behaviors. PMID:22654807

Differential effects of α4β7 and GPR15 on homing of effector and regulatory T cells from patients with UC to the inflamed gut in vivo

PubMed Central

Fischer, Anika; Zundler, Sebastian; Atreya, Raja; Rath, Timo; Voskens, Caroline; Hirschmann, Simon; López-Posadas, Rocío; Watson, Alastair; Becker, Christoph; Schuler, Gerold; Neufert, Clemens; Atreya, Imke; Neurath, Markus F

2016-01-01

Objective Gut homing of lymphocytes via adhesion molecules has recently emerged as new target for therapy in IBDs. We aimed to analyse the in vivo homing of effector (Teff) and regulatory (Treg) T cells to the inflamed gut via α4β7 and G protein receptor GPR15. Design We assessed the expression of homing receptors on T cells in peripheral blood and inflamed mucosa. We studied the migration pattern and homing of Teff and Treg cells to the inflamed gut using intravital confocal microscopy and FACS in a humanised mouse model in dextran sodium sulfate-treated NSG (NOD.Cg-Prkdcscid-Il2rgtm1Wjl/SzJ) mice. Results Expression of GPR15 and α4β7 was significantly increased on Treg rather than Teff cells in peripheral blood of patients with UC as compared with Crohn’s disease and controls. In vivo analysis in a humanised mouse model showed augmented gut homing of UC Treg cells as compared with controls. Moreover, suppression of UC (but not control) Teff and Treg cell homing was noted upon treatment with the α4β7 antibody vedolizumab. In contrast, siRNA blockade of GPR15 had only effects on homing of Teff cells but did not affect Treg homing in UC. Clinical vedolizumab treatment was associated with marked expansion of UC Treg cells in peripheral blood. Conclusions α4β7 rather than GPR15 is crucial for increased colonic homing of UC Treg cells in vivo, while both receptors control UC Teff cell homing. Vedolizumab treatment impairs homing of UC Treg cells leading to their accumulation in peripheral blood with subsequent suppression of systemic Teff cell expansion. PMID:26209553

STAT3 Knockdown Reduces Pancreatic Cancer Cell Invasiveness and Matrix Metalloproteinase-7 Expression in Nude Mice

PubMed Central

Huang, Ke jian; Wu, Wei dong; Jiang, Tao; Cao, Jun; Feng, Zhen zhong; Qiu, Zheng jun

2011-01-01

Aims Transducer and activator of transcription-3 (STAT3) plays an important role in tumor cell invasion and metastasis. The aim of the present study was to investigate the effects of STAT3 knockdown in nude mouse xenografts of pancreatic cancer cells and underlying gene expression. Methods A STAT3 shRNA lentiviral vector was constructed and infected into SW1990 cells. qRT-PCR and western immunoblot were performed to detect gene expression. Nude mouse xenograft assays were used to assess changes in phenotypes of these stable cells in vivo. HE staining was utilized to evaluate tumor cell invasion and immunohistochemistry was performed to analyze gene expression. Results STAT3 shRNA successfully silenced expression of STAT3 mRNA and protein in SW1990 cells compared to control cells. Growth rate of the STAT3-silenced tumor cells in nude mice was significantly reduced compared to in the control vector tumors and parental cells-generated tumors. Tumor invasion into the vessel and muscle were also suppressed in the STAT3-silenced tumors compared to controls. Collagen IV expression was complete and continuous surrounding the tumors of STAT3-silenced SW1990 cells, whereas collagen IV expression was incomplete and discontinuous surrounding the control tumors. Moreover, microvessel density was significantly lower in STAT3-silenced tumors than parental or control tumors of SW1990 cells. In addition, MMP-7 expression was reduced in STAT3-silenced tumors compared to parental SW1990 xenografts and controls. In contrast, expression of IL-1β and IgT7α was not altered. Conclusion These data clearly demonstrate that STAT3 plays an important role in regulation of tumor growth, invasion, and angiogenesis, which could be act by reducing MMP-7 expression in pancreatic cancer cells. PMID:21991388

Apoptosis-Resistant Cardiac Progenitor Cells Modified With Apurinic/Apyrimidinic Endonuclease/Redox Factor 1 Gene Overexpression Regulate Cardiac Repair After Myocardial Infarction.

PubMed

Aonuma, Tatsuya; Takehara, Naofumi; Maruyama, Keisuke; Kabara, Maki; Matsuki, Motoki; Yamauchi, Atsushi; Kawabe, Jun-Ichi; Hasebe, Naoyuki

2016-08-01

: Overcoming the insufficient survival of cell grafts is an essential objective in cell-based therapy. Apurinic/apyrimidinic endonuclease/redox factor 1 (APE1) promotes cell survival and may enhance the therapeutic effect of engrafted cells. The aim of this study is to determine whether APE1 overexpression in cardiac progenitor cells (CPCs) could ameliorate the efficiency of cell-based therapy. CPCs isolated from 8- to 10-week-old C57BL/6 mouse hearts were infected with retrovirus harboring APE1-DsRed (APE1-CPC) or a DsRed control (control-CPC). Oxidative stress-induced apoptosis was then assessed in APE1-CPCs, control-CPCs, and neonatal rat ventricular myocytes (NRVMs) cocultured with these CPCs. This analysis revealed that APE1 overexpression inhibited CPC apoptosis with activation of transforming growth factor β-activated kinase 1 (TAK1) and nuclear factor (NF)-κB. In the coculture model, NRVM apoptosis was inhibited to a greater extent in the presence of APE1-CPCs compared with control-CPCs. Moreover, the number of surviving DsRed-positive CPC grafts was significantly higher 7 days after the transplant of APE1-CPCs into a mouse myocardial infarction model, and the left ventricular ejection fraction showed greater improvement with attenuation of fibrosis 28 days after the transplant of APE1-CPCs compared with control-CPCs. Additionally, fewer inflammatory macrophages and a higher percentage of cardiac α-sarcomeric actinin-positive CPC-grafts were observed in mice injected with APE1-CPCs compared with control-CPCs after 7 days. In conclusion, antiapoptotic APE1-CPC graft, which increased TAK1-NF-κB pathway activation, survived effectively in the ischemic heart, restored cardiac function, and reduced cardiac inflammation and fibrosis. APE1 overexpression in CPCs may serve as a novel strategy to improve cardiac cell therapy. Improving the survival of cell grafts is essential to maximize the efficacy of cell therapy. The authors investigated the role of APE1 in CPCs under ischemic conditions and evaluated the therapeutic efficacy of transplanted APE1-overexpressing CPCs in a mouse model of myocardial infarction. APE1 hindered apoptosis in CPC grafts subjected to oxidative stress caused in part by increased TAK1-NF-κB pathway activation. Furthermore, APE1-CPC grafts that effectively survived in the ischemic heart restored cardiac function and attenuated fibrosis through pleiotropic mechanisms that remain to be characterized. These findings suggest that APE1 overexpression in CPCs may be a novel strategy to reinforce cardiac cell therapy. ©AlphaMed Press.

Metabolic coupling of glutathione between mouse and quail cardiac myocytes and its protective role against oxidative stress.

PubMed

Nakamura, T Y; Yamamoto, I; Kanno, Y; Shiba, Y; Goshima, K

1994-05-01

Cultured quail myocytes were much more resistant to H2O2 toxicity than cultured mouse myocytes. The intracellular concentration of glutathione ([GSH]i) and the activity of gamma-glutamylcysteine synthetase (gamma-GCS) in quail heart cells were about five and three times higher, respectively, than in mouse heart cells, although catalase and glutathione peroxidase (GSHpx) activity was similar in both. Preloading of gamma-glutamylcysteine monoethyl ester (gamma-GCE), a membrane-permeating GSH precursor, increased the H2O2 resistance of cultured mouse myocytes. These observations suggest that the high [GSH]i and the high activity of gamma-GCS in quail myocytes are responsible for their high resistance to H2O2. Both H2O2 sensitivity and [GSH]i of mosaic sheets composed of equal amounts of mouse and quail myocytes approximated those of sheets composed entirely of quail myocytes. From these observations, it is hypothesized that GSH was transferred from quail myocytes to mouse myocytes, probably through gap junctions between them, and that quail myocytes resynthesized GSH by a feedback mechanism, thus maintaining their intracellular GSH levels. When the fluorescent dye lucifer yellow was injected into a beating quail myocyte in a mosaic sheet, it spread to neighboring mouse myocytes but not to neighboring L cells (a cell line derived from mouse connective tissue). These observations indicate that existence of gap junctions in the region of cell contact between mouse and quail myocytes but not between quail myocytes and L cells. When quail myocytes preloaded with [3H]gamma-GCE were cocultured with mouse myocytes and L cells, the radioactivity was transmitted to neighboring mouse myocytes but not L cells. These observations show that GSH and/or its precursors can be transmitted from quail myocytes to mouse myocytes through gap junctions and that this can protect mouse myocytes from H2O2 toxicity. Mouse myocyte sheets composed of 10(4) cells or more showed higher resistance to H2O2 toxicity than single isolated mouse myocytes. Metabolic coupling of GSH between myocytes may contribute at least in part to this high resistance of the cell sheets.

Cell Motility and Invasiveness of Neurofibromin-Deficient Neural Crest Cells and Malignant Triton Tumor Lines

DTIC Science & Technology

2005-06-01

derived cells, we isolated first branchial arch mesenchymal populations, as well as trigeminal ganglion non-neuronal cells, from mouse embryos and measured...demonstrate that loss of neurofibromin affects the invasiveness of neural crest-derived (trigeminal ganglion) and cranial mesenchymal ( branchial arch) cell...trigeminal and branchial arch cells between El0 and El 2 indicates that the roles of neurofibromin in controlling motility may become increasingly

The concentration-dependent effect of progesterone on follicle growth in the mouse ovary.

PubMed

Komatsu, Kouji; Masubuchi, Satoru

2017-06-21

Follicle growth in the mammalian ovary is coordinately controlled by multiple factors to sustain periodic ovulation. In this study, we investigated the role of progesterone on follicle growth in the mouse ovary. As the concentration of progesterone changes during the estrus cycle, we cultured the sliced mouse ovary in a medium containing 10 ng/ml, 100 ng/ml, and 1 μg/ml progesterone. Progesterone promoted the growth of primordial to primary follicles at 100 ng/ml, while it suppressed the growth of secondary follicles at 1 μg/ml. Follicles at other developmental stages in the cultured ovary were unaffected with different concentrations of progesterone. The number of ovulated oocytes increased in the medium containing 100 ng/ml progesterone but decreased in the presence of 1 μg/ml progesterone. Follicles expressed two types of progesterone receptors, progesterone receptor (PGR) and PGR membrane component 1 (PGRMC1). While PGR shows transient expression on granulosa cells of Graafian follicles, PGRMC1 expresses in granulosa cells of developing follicles. These results suggest that progesterone controls the growth of developing follicles through PGRMC1. Our study shows that the effect of progesterone on ovulation and follicle growth in mouse ovary is dependent on the concentration of progesterone and the follicle stage.

Stabilization and localization of Xist RNA are controlled by separate mechanisms and are not sufficient for X inactivation.

PubMed

Clemson, C M; Chow, J C; Brown, C J; Lawrence, J B

1998-07-13

These studies address whether XIST RNA is properly localized to the X chromosome in somatic cells where human XIST expression is reactivated, but fails to result in X inactivation (Tinker, A.V., and C.J. Brown. 1998. Nucl. Acids Res. 26:2935-2940). Despite a nuclear RNA accumulation of normal abundance and stability, XIST RNA does not localize in reactivants or in naturally inactive human X chromosomes in mouse/ human hybrid cells. The XIST transcripts are fully stabilized despite their inability to localize, and hence XIST RNA localization can be uncoupled from stabilization, indicating that these are separate steps controlled by distinct mechanisms. Mouse Xist RNA tightly localized to an active X chromosome, demonstrating for the first time that the active X chromosome in somatic cells is competent to associate with Xist RNA. These results imply that species-specific factors, present even in mature, somatic cells that do not normally express Xist, are necessary for localization. When Xist RNA is properly localized to an active mouse X chromosome, X inactivation does not result. Therefore, there is not a strict correlation between Xist localization and chromatin inactivation. Moreover, expression, stabilization, and localization of Xist RNA are not sufficient for X inactivation. We hypothesize that chromosomal association of XIST RNA may initiate subsequent developmental events required to enact transcriptional silencing.

Culture of preimplantation mouse embryos affects fetal development and the expression of imprinted genes.

PubMed

Khosla, S; Dean, W; Brown, D; Reik, W; Feil, R

2001-03-01

Culture of preimplantation mammalian embryos and cells can influence their subsequent growth and differentiation. Previously, we reported that culture of mouse embryonic stem cells is associated with deregulation of genomic imprinting and affects the potential for these cells to develop into normal fetuses. The purpose of our current study was to determine whether culture of preimplantation mouse embryos in a chemically defined medium (M16) with or without fetal calf serum (FCS) can affect their subsequent development and imprinted gene expression. Only one third of the blastocysts that had been cultured from two-cell embryos in M16 medium complemented with FCS developed into viable Day 14 fetuses after transfer into recipients. These M16 + FCS fetuses were reduced in weight as compared with controls and M16 fetuses and had decreased expression of the imprinted H19 and insulin-like growth factor 2 genes associated with a gain of DNA methylation at an imprinting control region upstream of H19. They also displayed increased expression of the imprinted gene Grb10. The growth factor receptor binding gene Grb7, in contrast, was strongly reduced in its expression in most of the M16 + FCS fetuses. No alterations were detected for the imprinted gene MEST: Preimplantation culture in the presence of serum can influence the regulation of multiple growth-related imprinted genes, thus leading to aberrant fetal growth and development.

Isolation and clonal characterization of hematopoietic and liver stem cells.

PubMed

Nakauchi, Hiromitsu

2004-11-01

Prospective isolation of stem cells is essential to understanding the mechanisms that control their proliferation and differentiation. Using 9 monoclonal antibodies and fluorescence-activated cell sorting (FACS), we have succeeded in prospectively identifying hematopoietic stem cells (HSCs) in adult mouse bone marrow. Mouse HSCs were exclusively enriched in CD34 negative, c-Kit Sca-1 Lineage Marker (CD34 KSL) cells representing 0.004% of bone marrow (BM) mononuclear cells. When single CD34-KSL cells were transplanted individually into a lethally irradiated mouse, 25% of the recipient mice survived and showed long-term reconstitution of the BM, providing evidence for multipotency and a self-renewal capacity of HSCs. Using a similar approach, we also prospectively identified hepatic stem cells with multilineage differentiation potential and self-renewal capability in the c-Met CD49f c-Kit CD45 Ter119 fraction of cells isolated from day 13.5 fetal mouse liver. On cell transplantation, these cells differentiated into hepatocytes and cholangiocytes. As an alternative to the antibody based stem cell isolation, Hoechst33342 staining is useful. To understand the mechanism responsible for SP phenotype, we performed an expression cloning and identified bcrp-1/ABCG2 gene, a member of ATP binding-cassette (ABC) transporter family. Bcrp-1 is almost exclusively expressed in CD34 KSL cells among blood cells; however their expression in other tissue specific stem cells remains to be studied. With the use of FACS and monoclonal antibodies, hematopoietic and liver stem cells were prospectively isolated and characterized. HSCs could also be purified by Hoechst 33342 staining. By expression cloning, we identify bcrp-1/ABCG2 transporter as a molecule responsible for SP phenotype. Elucidation of the physiological role of bcrp-1/ABCG2 in HSCs may provide us with clues to understand the molecular mechanisms of stem cell self-renewal and differentiation.

The effects of dexamethasone administered during pregnancy on the postpartum spiny mouse ovary

PubMed Central

Dobrowolski, Piotr; Pawlikowska-Pawlęga, Bożena; Tomaszewska, Ewa; Muszyński, Siemowit

2017-01-01

Excessive exposure to glucocorticoids can alter ovarian function by modulating oogenesis, folliculogenesis and steroidogenesis. The aim of the present study was to examine the effects of dexamethasone (DEX) administered during pregnancy on folliculogenesis and corpus luteum development in the postpartum spiny mouse ovary. DEX (125 μg kg-1 body weight per day) was applied to pregnant spiny mouse from day 20 of gestation to parturition. The obtained ovaries were fixed and used for immunohistochemistry and TEM analysis. The expression of proteins related to apoptosis (caspase-3, Bax, Bcl-2) and autophagy (Beclin1, Lamp1) as well as PCNA and GR receptors were evaluated by western-blot. In comparison with DEX-treated group a higher percentage of TUNEL positive granulosa and luteal cells was observed in the control group. These data were consistent with changes in caspase-3 and Bax expression, which increased in the control and decreased after DEX exposure. In turn, the proliferation index and PCNA expression were higher in the DEX-treated group. Moreover, the higher level of Beclin1, Lamp1, anti-apoptotic Bcl-2 protein and GR was observed in the DEX-treated females than in the control group. Beclin1 and Lamp1 were strongly expressed in luteal cells which exhibited an autophagic ultrastructure. Surprisingly, DEX augmented the number of ovarian follicles and corpora lutea, which resulted in a significant increase in ovarian weight. These findings suggest that DEX exerts anti-apoptotic action on granulosa layer and stimulates follicular maturation. Moreover, DEX induces autophagy in luteal cells promoting cell survival rather than cell death, which can prolong the corpus luteum life span. PMID:28827819

AhR modulates the IL-22-producing cell proliferation/recruitment in imiquimod-induced psoriasis mouse model.

PubMed

Cochez, Perrine M; Michiels, Camille; Hendrickx, Emilie; Van Belle, Astrid B; Lemaire, Muriel M; Dauguet, Nicolas; Warnier, Guy; de Heusch, Magali; Togbe, Dieudonnée; Ryffel, Bernhard; Coulie, Pierre G; Renauld, Jean-Christophe; Dumoutier, Laure

2016-06-01

IL-22 has a detrimental role in skin inflammatory processes, for example in psoriasis. As transcription factor, AhR controls the IL-22 production by several cell types (i.e. Th17 cells). Here, we analyzed the role of Ahr in IL-22 production by immune cells in the inflamed skin, using an imiquimod-induced psoriasis mouse model. Our results indicate that IL-22 is expressed in the ear of imiquimod-treated Ahr(-/-) mice but less than in wild-type mice. We then studied the role of AhR on three cell populations known to produce IL-22 in the skin: γδ T cells, Th17 cells, and ILC3, and a novel IL-22-producing cell type identified in this setting: CD4(-) CD8(-) TCRβ(+) T cells. We showed that AhR is required for IL-22 production by Th17, but not by the three other cell types, in the imiquimod-treated ears. Moreover, AhR has a role in the recruitment of γδ T cells, ILC3, and CD4(-) CD8(-) TCRβ(+) T cells into the inflamed skin or in their local proliferation. Taken together, AhR has a direct role in IL-22 production by Th17 cells in the mouse ear skin, but not by γδ T cells, CD4(-) CD8(-) TCRβ(+) T cells and ILCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

RNAi-Dependent and Independent Control of LINE1 Accumulation and Mobility in Mouse Embryonic Stem Cells

PubMed Central

Ciaudo, Constance; Jay, Florence; Okamoto, Ikuhiro; Chen, Chong-Jian; Sarazin, Alexis; Servant, Nicolas; Barillot, Emmanuel; Heard, Edith; Voinnet, Olivier

2013-01-01

In most mouse tissues, long-interspersed elements-1 (L1s) are silenced via methylation of their 5′-untranslated regions (5′-UTR). A gradual loss-of-methylation in pre-implantation embryos coincides with L1 retrotransposition in blastocysts, generating potentially harmful mutations. Here, we show that Dicer- and Ago2-dependent RNAi restricts L1 accumulation and retrotransposition in undifferentiated mouse embryonic stem cells (mESCs), derived from blastocysts. RNAi correlates with production of Dicer-dependent 22-nt small RNAs mapping to overlapping sense/antisense transcripts produced from the L1 5′-UTR. However, RNA-surveillance pathways simultaneously degrade these transcripts and, consequently, confound the anti-L1 RNAi response. In Dicer−/− mESC complementation experiments involving ectopic Dicer expression, L1 silencing was rescued in cells in which microRNAs remained strongly depleted. Furthermore, these cells proliferated and differentiated normally, unlike their non-complemented counterparts. These results shed new light on L1 biology, uncover defensive, in addition to regulatory roles for RNAi, and raise questions on the differentiation defects of Dicer−/− mESCs. PMID:24244175

Generation and Characterization of Transgenic Mice Expressing Mouse Ins1 Promoter for Pancreatic β-Cell-Specific Gene Overexpression and Knockout.

PubMed

Cheng, Yulong; Su, Yutong; Shan, Aijing; Jiang, Xiuli; Ma, Qinyun; Wang, Weiqing; Ning, Guang; Cao, Yanan

2015-07-01

The technologies for pancreatic β-cell-specific gene overexpression or knockout are fundamental for investigations of functional genes in vivo. Here we generated the Ins1-Cre-Dsred and Ins1-rtTA mouse models, which expressed the Cre recombinase or reverse tetracycline regulatable transactivator (rtTA) without hGH minigene under the control of mouse Ins1 promoter. Our data showed that the Cre-mediated recombination and rtTA-mediated activation could be efficiently detected at embryonic day 13.5 when these models were crossed with the reporter mice (ROSA(mT/mG) or tetO-HIST1H2BJ/GFP). The Cre and rtTA expression was restricted to β-cells without leakage in the brain and other tissues. Moreover, both the transgenic lines showed normal glucose tolerance and insulin secretion. These results suggested that the Ins1-Cre-Dsred and Ins1-rtTA mice could be used to knock out or overexpress target genes in embryos and adults to facilitate β-cell researches.

The common mouse protozoa Tritrichomonas muris alters mucosal T cell homeostasis and colitis susceptibility.

PubMed

Escalante, Nichole K; Lemire, Paul; Cruz Tleugabulova, Mayra; Prescott, David; Mortha, Arthur; Streutker, Catherine J; Girardin, Stephen E; Philpott, Dana J; Mallevaey, Thierry

2016-12-12

The mammalian gastrointestinal tract hosts a diverse community of microbes including bacteria, fungi, protozoa, helminths, and viruses. Through coevolution, mammals and these microbes have developed a symbiosis that is sustained through the host's continuous sensing of microbial factors and the generation of a tolerant or pro-inflammatory response. While analyzing T cell-driven colitis in nonlittermate mouse strains, we serendipitously identified that a nongenetic transmissible factor dramatically increased disease susceptibility. We identified the protozoan Tritrichomonas muris as the disease-exacerbating element. Furthermore, experimental colonization with T. muris induced an elevated Th1 response in the cecum of naive wild-type mice and accelerated colitis in Rag1 -/- mice after T cell transfer. Overall, we describe a novel cross-kingdom interaction within the murine gut that alters immune cell homeostasis and disease susceptibility. This example of unpredicted microbial priming of the immune response highlights the importance of studying trans-kingdom interactions and serves as a stark reminder of the importance of using littermate controls in all mouse research. © 2016 Escalante et al.

An inducible knockout mouse to model the cell-autonomous role of PTEN in initiating endometrial, prostate and thyroid neoplasias.

PubMed

Mirantes, Cristina; Eritja, Núria; Dosil, Maria Alba; Santacana, Maria; Pallares, Judit; Gatius, Sónia; Bergadà, Laura; Maiques, Oscar; Matias-Guiu, Xavier; Dolcet, Xavier

2013-05-01

PTEN is one of the most frequently mutated tumor suppressor genes in human cancers. The role of PTEN in carcinogenesis has been validated by knockout mouse models. PTEN heterozygous mice develop neoplasms in multiple organs. Unfortunately, the embryonic lethality of biallelic excision of PTEN has inhibited the study of complete PTEN deletion in the development and progression of cancer. By crossing PTEN conditional knockout mice with transgenic mice expressing a tamoxifen-inducible Cre-ER(T) under the control of a chicken actin promoter, we have generated a tamoxifen-inducible mouse model that allows temporal control of PTEN deletion. Interestingly, administration of a single dose of tamoxifen resulted in PTEN deletion mainly in epithelial cells, but not in stromal, mesenchymal or hematopoietic cells. Using the mT/mG double-fluorescent Cre reporter mice, we demonstrate that epithelial-specific PTEN excision was caused by differential Cre activity among tissues and cells types. Tamoxifen-induced deletion of PTEN resulted in extremely rapid and consistent formation of endometrial in situ adenocarcinoma, prostate intraepithelial neoplasia and thyroid hyperplasia. We also analyzed the role of PTEN ablation in other epithelial cells, such as the tubular cells of the kidney, hepatocytes, colonic epithelial cells or bronchiolar epithelium, but those tissues did not exhibit neoplastic growth. Finally, to validate this model as a tool to assay the efficacy of anti-tumor drugs in PTEN deficiency, we administered the mTOR inhibitor everolimus to mice with induced PTEN deletion. Everolimus dramatically reduced the progression of endometrial proliferations and significantly reduced thyroid hyperplasia. This model could be a valuable tool to study the cell-autonomous mechanisms involved in PTEN-loss-induced carcinogenesis and provides a good platform to study the effect of anti-neoplastic drugs on PTEN-negative tumors.

An inducible knockout mouse to model the cell-autonomous role of PTEN in initiating endometrial, prostate and thyroid neoplasias

PubMed Central

Mirantes, Cristina; Eritja, Núria; Dosil, Maria Alba; Santacana, Maria; Pallares, Judit; Gatius, Sónia; Bergadà, Laura; Maiques, Oscar; Matias-Guiu, Xavier; Dolcet, Xavier

2013-01-01

SUMMARY PTEN is one of the most frequently mutated tumor suppressor genes in human cancers. The role of PTEN in carcinogenesis has been validated by knockout mouse models. PTEN heterozygous mice develop neoplasms in multiple organs. Unfortunately, the embryonic lethality of biallelic excision of PTEN has inhibited the study of complete PTEN deletion in the development and progression of cancer. By crossing PTEN conditional knockout mice with transgenic mice expressing a tamoxifen-inducible Cre-ERT under the control of a chicken actin promoter, we have generated a tamoxifen-inducible mouse model that allows temporal control of PTEN deletion. Interestingly, administration of a single dose of tamoxifen resulted in PTEN deletion mainly in epithelial cells, but not in stromal, mesenchymal or hematopoietic cells. Using the mT/mG double-fluorescent Cre reporter mice, we demonstrate that epithelial-specific PTEN excision was caused by differential Cre activity among tissues and cells types. Tamoxifen-induced deletion of PTEN resulted in extremely rapid and consistent formation of endometrial in situ adenocarcinoma, prostate intraepithelial neoplasia and thyroid hyperplasia. We also analyzed the role of PTEN ablation in other epithelial cells, such as the tubular cells of the kidney, hepatocytes, colonic epithelial cells or bronchiolar epithelium, but those tissues did not exhibit neoplastic growth. Finally, to validate this model as a tool to assay the efficacy of anti-tumor drugs in PTEN deficiency, we administered the mTOR inhibitor everolimus to mice with induced PTEN deletion. Everolimus dramatically reduced the progression of endometrial proliferations and significantly reduced thyroid hyperplasia. This model could be a valuable tool to study the cell-autonomous mechanisms involved in PTEN-loss-induced carcinogenesis and provides a good platform to study the effect of anti-neoplastic drugs on PTEN-negative tumors. PMID:23471917

Expression of HLA Class II Molecules in Humanized NOD.Rag1KO.IL2RgcKO Mice Is Critical for Development and Function of Human T and B Cells

PubMed Central

Danner, Rebecca; Chaudhari, Snehal N.; Rosenberger, John; Surls, Jacqueline; Richie, Thomas L.; Brumeanu, Teodor-Doru; Casares, Sofia

2011-01-01

Background Humanized mice able to reconstitute a surrogate human immune system (HIS) can be used for studies on human immunology and may provide a predictive preclinical model for human vaccines prior to clinical trials. However, current humanized mouse models show sub-optimal human T cell reconstitution and limited ability to support immunoglobulin class switching by human B cells. This limitation has been attributed to the lack of expression of Human Leukocyte Antigens (HLA) molecules in mouse lymphoid organs. Recently, humanized mice expressing HLA class I molecules have been generated but showed little improvement in human T cell reconstitution and function of T and B cells. Methods We have generated NOD.Rag1KO.IL2RγcKO mice expressing HLA class II (HLA-DR4) molecules under the I-Ed promoter that were infused as adults with HLA-DR-matched human hematopoietic stem cells (HSC). Littermates lacking expression of HLA-DR4 molecules were used as control. Results HSC-infused HLA-DR4.NOD.Rag1KO.IL-2RγcKO mice developed a very high reconstitution rate (>90%) with long-lived and functional human T and B cells. Unlike previous humanized mouse models reported in the literature and our control mice, the HLA-DR4 expressing mice reconstituted serum levels (natural antibodies) of human IgM, IgG (all four subclasses), IgA, and IgE comparable to humans, and elicited high titers of specific human IgG antibodies upon tetanus toxoid vaccination. Conclusions Our study demonstrates the critical role of HLA class II molecules for development of functional human T cells able to support immunoglobulin class switching and efficiently respond to vaccination. PMID:21611197

Inadequate satellite cell replication compromises muscle regrowth following postnatal nutrient restriction

USDA-ARS?s Scientific Manuscript database

Perinatal growth impairment permanently compromises skeletal muscle mass. The present study assessed the contribution of muscle satellite cell replicative capacity to this deficit. Mouse dams were fed either a low protein (LP, n=7) or control (C, n=6) diet during lactation. Pups were weaned at 21 d ...

Enhanced Glucose Control Following Vertical Sleeve Gastrectomy Does Not Require a β-Cell Glucagon-Like Peptide 1 Receptor.

PubMed

Douros, Jonathan D; Lewis, Alfor G; Smith, Eric P; Niu, JingJing; Capozzi, Megan; Wittmann, April; Campbell, Jonathan; Tong, Jenny; Wagner, Constance; Mahbod, Parinaz; Seeley, Randy; D'Alessio, David A

2018-05-14

Bariatric surgeries, including vertical sleeve gastrectomy (VSG), resolve diabetes in 40-50% of patients. Studies examining the molecular mechanisms underlying this effect have centered on the role of the insulinotropic glucagon-like peptide 1 (GLP-1), in great part because of the ∼10-fold rise in its circulating levels after surgery. However, there is currently debate over the role of direct β-cell signaling by GLP-1 to mediate improved glucose tolerance following surgery. In order to assess the importance of β-cell GLP-1 receptor (GLP-1R) for improving glucose control after VSG, a mouse model of this procedure was developed and combined with a genetically modified mouse line allowing an inducible, β-cell specific Glp1r knockdown ( Glp1r β-cell-ko ). Mice with VSG lost ∼20% of body weight over 30 days compared to sham-operated controls and had a ∼60% improvement in glucose tolerance. Isolated islets from VSG mice had significantly greater insulin responses to glucose than controls. Glp1r knockdown in β-cells caused glucose intolerance in diet-induced obese mice compared to obese controls, but VSG improved glycemic profiles to similar levels during oral and intraperitoneal glucose challenges in Glp1r βcell-ko and Glp1r WT mice. Therefore, while the β-cell GLP-1R seems to be important for maintaining glucose tolerance in obese mice, in these experiments it is dispensable for the improvement in glucose tolerance after VSG. Moreover, the metabolic physiology activated by VSG can overcome the deficits in glucose regulation caused by lack of β-cell GLP-1 signaling in obesity. © 2018 by the American Diabetes Association.

Protective effects of vaccines against Bordetella parapertussis in a mouse intranasal challenge model.

PubMed

Komatsu, Eiji; Yamaguchi, Fuminori; Eguchi, Masahiro; Watanabe, Mineo

2010-06-17

Bordetella parapertussis causes typical whooping cough, as does Bordetella pertussis. However, current commercial vaccines are ineffective against B. parapertussis. In an effort to develop vaccines that are effective in protecting against both B. pertussis and B. parapertussis, we examined the protective effects of vaccines prepared from whole-cells and from recombinant proteins derived from B. parapertussis in a mouse intranasal challenge model. We confirmed current pertussis vaccines did not induce protective immunity against B. parapertussis in the mouse model. A whole-cell vaccine prepared from B. parapertussis induced protective immunity against B. parapertussis but not against B. pertussis, suggesting a combination of a current pertussis vaccine with a whole-cell parapertussis vaccine might prevent whooping cough caused by both species of Bordetella. We also found that filamentous hemagglutinin was a protective antigen of B. parapertussis. Our observations should lead to the development of new pertussis vaccines that can control the two prevalent forms of whooping cough.

Inhibition of HMG CoA reductase reveals an unexpected role for cholesterol during PGC migration in the mouse

PubMed Central

Ding, Jiaxi; Jiang, DeChen; Kurczy, Michael; Nalepka, Jennifer; Dudley, Brian; Merkel, Erin I; Porter, Forbes D; Ewing, Andrew G; Winograd, Nicholas; Burgess, James; Molyneaux, Kathleen

2008-01-01

Background Primordial germ cells (PGCs) are the embryonic precursors of the sperm and eggs. Environmental or genetic defects that alter PGC development can impair fertility or cause formation of germ cell tumors. Results We demonstrate a novel role for cholesterol during germ cell migration in mice. Cholesterol was measured in living tissue dissected from mouse embryos and was found to accumulate within the developing gonads as germ cells migrate to colonize these structures. Cholesterol synthesis was blocked in culture by inhibiting the activity of HMG CoA reductase (HMGCR) resulting in germ cell survival and migration defects. These defects were rescued by co-addition of isoprenoids and cholesterol, but neither compound alone was sufficient. In contrast, loss of the last or penultimate enzyme in cholesterol biosynthesis did not alter PGC numbers or position in vivo. However embryos that lack these enzymes do not exhibit cholesterol defects at the stage at which PGCs are migrating. This demonstrates that during gestation, the cholesterol required for PGC migration can be supplied maternally. Conclusion In the mouse, cholesterol is required for PGC survival and motility. It may act cell-autonomously by regulating clustering of growth factor receptors within PGCs or non cell-autonomously by controlling release of growth factors required for PGC guidance and survival. PMID:19117526

Localization and regulation of glucagon receptors in the chick eye and preproglucagon and glucagon receptor expression in the mouse eye.

PubMed

Feldkaemper, Marita P; Burkhardt, Eva; Schaeffel, Frank

2004-09-01

Myopia is a condition in which the eye is too long for the focal length of cornea and lens. Analysis of the messengers that are released by the retina to control axial eye growth in the animal model of the chicken revealed that glucagon-immunoreactive amacrine cells are involved in the retinal image processing that controls the growth of the sclera. It was found that the amount of retinal glucagon mRNA increased during treatment with positive lenses and pharmacological studies supported the idea that glucagon may act as a stop signal for eye growth. Glucagon exerts its regulatory effects by binding to a single type of glucagon receptor. In this study, we have sequenced the chicken glucagon receptor and compared its DNA and amino acid sequence with the human and mouse homologues. After sequencing about 80% of the receptor, we found a homology between 79.4 and 75.6% on cDNA level. At the protein level, about 73% of the amino acids were identical. Moreover, the cellular localization and regulation of the glucagon receptor in the chick retina was studied. In situ hybridization studies showed that many cells in the ganglion cell layer and inner nuclear layer, and some cells in the outer nuclear layer, express the receptor mRNA. Injection of the glucagon agonist Lys17,18,Glu21-glucagon induced a down-regulation of glucagon receptor mRNA content. Since the mouse would be an attractive mammalian model to study the biochemical and genetic basis of myopia, and because recent studies have demonstrated that form deprivation myopia can be induced, the expression of preproglucagon and glucagon receptor genes were also studied in the mouse retina and were found to be expressed.

Mouse neuroblastoma cell based model and the effect of epileptic events on calcium oscillations and neural spikes

NASA Astrophysics Data System (ADS)

Kim, Suhwan; Baek, Juyeong; Jung, Unsang; Lee, Sangwon; Jung, Woonggyu; Kim, Jeehyun; Kang, Shinwon

2013-05-01

Recently, Mouse neuroblastoma cells are considered as an attractive model for the study of human neurological and prion diseases, and intensively used as a model system in different areas. Among those areas, differentiation of neuro2a (N2A) cells, receptor mediated ion current, and glutamate induced physiological response are actively investigated. The reason for the interest to mouse neuroblastoma N2A cells is that they have a fast growing rate than other cells in neural origin with a few another advantages. This study evaluated the calcium oscillations and neural spikes recording of mouse neuroblastoma N2A cells in an epileptic condition. Based on our observation of neural spikes in mouse N2A cell with our proposed imaging modality, we report that mouse neuroblastoma N2A cells can be an important model related to epileptic activity studies. It is concluded that the mouse neuroblastoma N2A cells produce the epileptic spikes in vitro in the same way as produced by the neurons or the astrocytes. This evidence advocates the increased and strong level of neurotransmitters release by enhancement in free calcium using the 4-aminopyridine which causes the mouse neuroblastoma N2A cells to produce the epileptic spikes and calcium oscillation.

The Terminator mouse is a diphtheria toxin-receptor knock-in mouse strain for rapid and efficient enrichment of desired cell lineages.

PubMed

Guo, Jian-Kan; Shi, Hongmei; Koraishy, Farrukh; Marlier, Arnaud; Ding, Zhaowei; Shan, Alan; Cantley, Lloyd G

2013-11-01

Biomedical research often requires primary cultures of specific cell types, which are challenging to obtain at high purity in a reproducible manner. Here we engineered the murine Rosa26 locus by introducing the diphtheria toxin receptor flanked by loxP sites. The resultant strain was nicknamed the Terminator mouse. This approach results in diphtheria toxin-receptor expression in all non-Cre expressing cell types, making these cells susceptible to diphtheria toxin exposure. In primary cultures of kidney cells derived from the Terminator mouse, over 99.99% of cells were dead within 72 h of diphtheria toxin treatment. After crossing the Terminator with the podocin-Cre (podocyte specific) mouse or the Ggt-Cre (proximal tubule specific) mouse, diphtheria toxin treatment killed non-Cre expressing cells but spared podocytes and proximal tubule cells, respectively, enriching the primary cultures to over 99% purity, based on both western blotting and immunostaining of marker proteins. Thus, the Terminator mouse can be a useful tool to selectively and reproducibly obtain even low-abundant cell types at high quantity and purity.

A non-invasive approach to monitor chronic lymphocytic leukemia engraftment in a xenograft mouse model using ultra-small superparamagnetic iron oxide-magnetic resonance imaging (USPIO-MRI).

PubMed

Valdora, Francesca; Cutrona, Giovanna; Matis, Serena; Morabito, Fortunato; Massucco, Carlotta; Emionite, Laura; Boccardo, Simona; Basso, Luca; Recchia, Anna Grazia; Salvi, Sandra; Rosa, Francesca; Gentile, Massimo; Ravina, Marco; Pace, Daniele; Castronovo, Angela; Cilli, Michele; Truini, Mauro; Calabrese, Massimo; Neri, Antonino; Neumaier, Carlo Emanuele; Fais, Franco; Baio, Gabriella; Ferrarini, Manlio

2016-11-01

Chronic lymphocytic leukemia (CLL) is the most prevalent leukemia among adults. Despite its indolent nature, CLL remains an incurable disease. Herein we aimed to monitor CLL disease engraftment and, progression/regression in a xenograft CLL mouse model using ultra-small superparamagnetic iron oxide-magnetic resonance imaging (USPIO-MRI). Spleen contrast enhancement, quantified as percentage change in signal intensity upon USPIO administration, demonstrated a difference due to a reduced USPIO uptake, in the spleens of mice injected with CLL cells (NSG-CLL, n=71) compared to controls (NSG-CTR, n=17). These differences were statistically significant both after 2 and 4weeks from CLL cells injection. In addition comparison of mice treated with rituximab with untreated controls for changes in spleen iron uptake confirmed that it is possible to monitor treatment efficacy in this mouse model of CLL using USPIO-enhanced MRI. Further applications could include the preclinical in vivo monitoring of new therapies and the clinical evaluation of CLL patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of oxidative stress on hyperglycaemia-induced brain malformations in a diabetes mouse model.

PubMed

Jin, Ya; Wang, Guang; Han, Sha-Sha; He, Mei-Yao; Cheng, Xin; Ma, Zheng-Lai; Wu, Xia; Yang, Xuesong; Liu, Guo-Sheng

2016-09-10

Pregestational diabetes mellitus (PGDM) enhances the risk of fetal neurodevelopmental defects. However, the mechanism of hyperglycaemia-induced neurodevelopmental defects is not fully understood. In this study, several typical neurodevelopmental defects were identified in the streptozotocin-induced diabetes mouse model. The neuron-specific class III beta-tubulin/forkhead box P1-labelled neuronal differentiation was suppressed and glial fibrillary acidic protein-labelled glial cell lineage differentiation was slightly promoted in pregestational diabetes mellitus (PGDM) mice. Various concentrations of glucose did not change the U87 cell viability, but glial cell line-derived neurotrophic factor expression was altered with varying glucose concentrations. Mouse maternal hyperglycaemia significantly increased Tunel(+) apoptosis but did not dramatically affect PCNA(+) cell proliferation in the process. To determine the cause of increased apoptosis, we determined the SOD activity, the expression of Nrf2 as well as its downstream anti-oxidative factors NQO1 and HO1, and found that all of them significantly increased in PGDM fetal brains compared with controls. However, Nrf2 expression in U87 cells was not significantly changed by different glucose concentrations. In mouse telencephalon, we observed the co-localization of Tuj-1 and Nrf2 expression in neurons, and down-regulating of Nrf2 in SH-SY5Y cells altered the viability of SH-SY5Y cells exposed to high glucose concentrations. Taken together, the data suggest that Nrf2-modulated antioxidant stress plays a crucial role in maternal hyperglycaemia-induced neurodevelopmental defects. Copyright © 2016 Elsevier Inc. All rights reserved.

Differential biological effects of dehydroepiandrosterone (DHEA) between mouse (B16F10) and human melanoma (BLM) cell lines.

PubMed

Joshi, Kumud; Hassan, Sherif S; Ramaraj, Pandurangan

2017-01-01

Dehydroepiandrosterone (DHEA) is a weak androgen and had been shown to have anti-cancer, anti-adipogenic and anti-inflammatory effects on mouse and other rodent models, but not on humans, suggesting a systemic level difference between mouse and human. Our previous study on DHEA biological functions involving a variety of cell lines, suggested that the functional differences between mouse and human existed even at the cellular level. Hence, using mouse and human melanoma cell models, in-vitro effects of DHEA on cell growth, mechanism of cell death and mechanism of DHEA action were studied. Results indicated a differential biological effects of DHEA between mouse and human melanoma cell lines. These in-vitro studies also suggested that the differential biological effects observed between these two cell lines could be due to the difference in the way DHEA was processed or metabolized inside the cell.

The effect of various immunosuppressive agents on mouse peritoneal macrophages and on the in vitro phagocytosis of Escherichia coli O4:K3:H5 and degradation of 125I-labelled HSA-antibody complexes by these cells.

PubMed Central

Gadeberg, O V; Rhodes, J M; Larsen, S O

1975-01-01

Large doses of hydrocortisone, cyclophosphamide, and methotrexate injected subcutaneously, and whole-body irradiation (500 rads) caused a reduction in the number of peritoneal cells (PE cells) obtained after intraperitoneal injection of the treated mice with proteose-peptone. The same dose of cyclophosphamide and irradiation induced morphological changes in PE macrophages. There were more giant cells in the peritoneal exudates from treated mice as compared to control mice. 'Pharmacological' and larger doses of hydrocortisone, methotrexate and azathioprine or anti-lymphocyte globulin had no effect on the in vitro phagocytic capacity of proteose-peptone-stimulated mouse PE macrophages. This also applied to doses of up to 50 mg/kg of cyclophosphamide. In contrast, whole-body irradiation (500 rad) and 100 mg/kg of cyclophosphamide decreased the phagocytic capacity of mouse macrophages in vitro and reduced the ability of PE cells to degrade 125I-labelled HSA-antibody complexes in vitro. The greatest effect was noted 4-5 days after whole-body irradiation or four to five subcutaneous injections of cyclophosphamide. Images Figure 1 Figure 2 PMID:1090520

A developmentally plastic adult mouse kidney cell line spontaneously generates multiple adult kidney structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Webb, Carol F., E-mail: carol-webb@omrf.org; Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK

Despite exciting new possibilities for regenerative therapy posed by the ability to induce pluripotent stem cells, recapitulation of three-dimensional kidneys for repair or replacement has not been possible. ARID3a-deficient mouse tissues generated multipotent, developmentally plastic cells. Therefore, we assessed the adult mouse ARID3a−/− kidney cell line, KKPS5, which expresses renal progenitor surface markers as an alternative cell source for modeling kidney development. Remarkably, these cells spontaneously developed into multicellular nephron-like structures in vitro, and engrafted into immunocompromised medaka mesonephros, where they formed mouse nephron structures. These data implicate KKPS5 cells as a new model system for studying kidney development. - Highlights:more » • An ARID3a-deficient mouse kidney cell line expresses multiple progenitor markers. • This cell line spontaneously forms multiple nephron-like structures in vitro. • This cell line formed mouse kidney structures in immunocompromised medaka fish kidneys. • Our data identify a novel model system for studying kidney development.« less

Complete TCRα gene locus control region activity in T cells derived in vitro from embryonic stem cells

PubMed Central

Lahiji, Armin; Kučerová-Levisohn, Martina; Lovett, Jordana; Holmes, Roxanne; Zúñiga-Pflücker, Juan Carlos; Ortiz, Benjamin D.

2013-01-01

Locus Control Regions (LCR) are cis-acting gene regulatory elements with the unique, integration site-independent ability to transfer the characteristics of their locus-of-origin’s gene expression pattern to a linked transgene in mice. LCR activities have been discovered in numerous T cell lineage expressed gene loci. These elements can be adapted to the design of stem cell gene therapy vectors that direct robust therapeutic gene expression to the T cell progeny of engineered stem cells. Currently, transgenic mice provide the only experimental approach that wholly supports all the critical aspects of LCR activity. Herein we report manifestation of all key features of mouse T cell receptor (TCR)-α gene LCR function in T cells derived in vitro from mouse embryonic stem cells (ESC). High level, copy number-related TCRα LCR-linked reporter gene expression levels are cell type-restricted in this system, and upregulated during the expected stage transition of T cell development. We further report that de novo introduction of TCRα LCR linked transgenes into existing T cell lines yields incomplete LCR activity. Together, these data indicate that establishing full TCRα LCR activity requires critical molecular events occurring prior to final T-lineage determination. This study additionally validates a novel, tractable and more rapid approach for the study of LCR activity in T cells, and its translation to therapeutic genetic engineering. PMID:23720809

T cells establish and maintain CNS viral infection in HIV-infected humanized mice.

PubMed

Honeycutt, Jenna B; Liao, Baolin; Nixon, Christopher C; Cleary, Rachel A; Thayer, William O; Birath, Shayla L; Swanson, Michael D; Sheridan, Patricia; Zakharova, Oksana; Prince, Francesca; Kuruc, JoAnn; Gay, Cynthia L; Evans, Chris; Eron, Joseph J; Wahl, Angela; Garcia, J Victor

2018-06-04

The human brain is an important site of HIV replication and persistence during antiretroviral therapy (ART). Direct evaluation of HIV infection in the brains of otherwise healthy individuals is not feasible; therefore, we performed a large-scale study of bone marrow/liver/thymus (BLT) humanized mice as an in vivo model to study HIV infection in the brain. Human immune cells, including CD4+ T cells and macrophages, were present throughout the BLT mouse brain. HIV DNA, HIV RNA, and/or p24+ cells were observed in the brains of HIV-infected animals, regardless of the HIV isolate used. HIV infection resulted in decreased numbers of CD4+ T cells, increased numbers of CD8+ T cells, and a decreased CD4+/CD8+ T cell ratio in the brain. Using humanized T cell-only mice (ToM), we demonstrated that T cells establish and maintain HIV infection of the brain in the complete absence of human myeloid cells. HIV infection of ToM resulted in CD4+ T cell depletion and a reduced CD4+/CD8+ T cell ratio. ART significantly reduced HIV levels in the BLT mouse brain, and the immune cell populations present were indistinguishable from those of uninfected controls, which demonstrated the effectiveness of ART in controlling HIV replication in the CNS and returning cellular homeostasis to a pre-HIV state.

Mouse scrapie responsive gene 1 (Scrg1): genomic organization, physical linkage to sap30, genetic mapping on chromosome 8, and expression in neuronal primary cell cultures.

PubMed

Dron, M; Tartare, X; Guillo, F; Haik, S; Barbin, G; Maury, C; Tovey, M; Dandoy-Dron, F

2000-11-15

We have previously reported a transcript of a novel mouse gene (Scrg1) with increased expression in transmissible spongiform encephalopathies and the cloning of the human mRNA analogue. In this paper, we present the genomic organization of the mouse and human SCRG1 loci, which exhibit a high degree of conservation. The genes are composed of three exons; the two downstream exons contain the protein coding region. The mouse gene is expressed in brain tissue essentially as a 0.7-kb message but also as a minor 2.6-kb mRNA. We have sequenced 20 kb of DNA at the mouse Scrg1 locus and found that the longer transcript is the prolongation of the 0.7-kb mRNA to a polyadenylation site located about 2 kb further downstream. Sequencing revealed that the mouse Scrg1 gene is physically linked to Sap30, a gene that encodes a protein of the histone deacetylase complex, and genetic linkage mapping assigned the localization of Scrg1 to chromosome 8 between Ant1 and Hmg2. Northern blot analysis showed that Scrg1 is under strict developmental control in mouse embryo and is expressed by cells of neuronal origin in vitro. Comparison of the rat, mouse, and human SCRG1 proteins identified a box of 35 identical contiguous amino acids and a characteristic cysteine distribution pattern defining a new protein signature. Copyright 2000 Academic Press.

Kid depletion in mouse oocytes associated with multinucleated blastomere formation and inferior embryo development.

PubMed

Egashira, Akiyoshi; Yamauchi, Nobuhiko; Islam, Md Rashedul; Yamagami, Kazuki; Tanaka, Asami; Suyama, Hikaru; El-Sayed, El-Sharawy Mohamed; Tabata, Shoji; Kuramoto, Takashi

2016-08-01

This study investigated the knockdown (KD) of Kid on maturation developmental competence and multinucleation of mouse germinal vesicle (GV) oocytes after parthenogenetic activation. Data revealed that Kid messenger RNA (mRNA) was expressed in GV and MII stage oocyte and 1- and 2-cell embryos. Additionally, Kid mRNA expression in the Kid KD group decreased by nearly 46% compared to the control small interfering RNA (siRNA) groups. The rate of multinucleated embryos in the Kid KD group (52.4%) was significantly higher (P < 0.05) than the control siRNA group (4.7%). Finally, the developmental rates were significantly lower in the Kid siRNA group at > 4-cell stage (28.6% vs. 53.5%) and the blastocyst stage (2.4% vs. 23.3%) compared to the control siRNA groups. Suppression of Kid using siRNA caused multinucleation in early embryos with high frequency and it may increase 2- to 4-cell arrested embryos and reduce the developmental competence to blastocyst. © 2016 Japanese Society of Animal Science.

Mouse Retinal Pigmented Epithelial Cell Lines retain their phenotypic characteristics after transfection with Human Papilloma Virus: A new tool to further the study of RPE biology

PubMed Central

Catanuto, Paola; Espinosa-Heidmann, Diego; Pereira-Simon, Simone; Sanchez, Patricia; Salas, Pedro; Hernandez, Eleut; Cousins, Scott W.; Elliot, Sharon J.

2009-01-01

Development of immortalized mouse retinal pigmented epithelial cell (RPE) lines that retain many of their in vivo phenotypic characteristics, would aid in studies of ocular diseases including age related macular degeneration (AMD). RPE cells were isolated from 16 month old (estrogen receptor knockout) ERKOα and ERKOβ mice and their C57Bl/6 wild type littermates. RPE65 and cellular retinaldehyde binding protein (CRALBP) expression, in vivo markers of RPE cells, were detected by real-time RT-PCR and western analysis. We confirmed the presence of epithelial cell markers, ZO1, cytokeratin 8 and 18 by immunofluorescence staining. In addition, we confirmed the distribution of actin filaments and the expression of ezrin. To develop cell lines, RPE cells were isolated, propagated and immortalized using human papilloma virus (HPV) 16 (E6/E7). RPE-specific markers and morphology were assessed before and after immortalization. In wildtype littermate controls, there was no evidence of any alterations in the parameters that we examined including MMP-2, TIMP-2, collagen type IV, and estrogen receptor (ER) α and ERβ protein expression and ER copy number ratio. Therefore, immortalized mouse RPE cell lines that retain their in vivo phenotype can be isolated from either pharmacologically or genetically manipulated mice, and may be used to study RPE cell biology. PMID:19013153

Tissue specific characterisation of Lim-kinase 1 expression during mouse embryogenesis

PubMed Central

Lindström, Nils O.; Neves, Carlos; McIntosh, Rebecca; Miedzybrodzka, Zosia; Vargesson, Neil; Collinson, J. Martin

2012-01-01

The Lim-kinase (LIMK) proteins are important for the regulation of the actin cytoskeleton, in particular the control of actin nucleation and depolymerisation via regulation of cofilin, and hence may control a large number of processes during development, including cell tensegrity, migration, cell cycling, and axon guidance. LIMK1/LIMK2 knockouts disrupt spinal cord morphogenesis and synapse formation but other tissues and developmental processes that require LIMK are yet to be fully determined. To identify tissues and cell-types that may require LIMK, we characterised the pattern of LIMK1 protein during mouse embryogenesis. We showed that LIMK1 displays an expression pattern that is temporally dynamic and tissue-specific. In several tissues LIMK1 is detected in cell-types that also express Wilms’ tumour protein 1 and that undergo transitions between epithelial and mesenchymal states, including the pleura, epicardium, kidney nephrons, and gonads. LIMK1 was also found in a subset of cells in the dorsal retina, and in mesenchymal cells surrounding the peripheral nerves. This detailed study of the spatial and temporal expression of LIMK1 shows that LIMK1 expression is more dynamic than previously reported, in particular at sites of tissue–tissue interactions guiding multiple developmental processes. PMID:21167960

Genetically Engineered Mouse Models for Studying Inflammatory Bowel Disease

PubMed Central

Mizoguchi, Atsushi; Takeuchi, Takahito; Himuro, Hidetomo; Okada, Toshiyuki; Mizoguchi, Emiko

2015-01-01

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that is mediated by very complex mechanisms controlled by genetic, immune, and environmental factors. More than 74 kinds of genetically engineered mouse strains have been established since 1993 for studying IBD. Although mouse models cannot fully reflect human IBD, they have provided significant contributions for not only understanding the mechanism, but also developing new therapeutic means for IBD. Indeed, 20 kinds of genetically engineered mouse models carry the susceptibility genes identified in human IBD, and the functions of some other IBD susceptibility genes have also been dissected out using mouse models. Cutting-edge technologies such as cell-specific and inducible knockout systems, which were recently employed to mouse IBD models, have further enhanced the ability of investigators to provide important and unexpected rationales for developing new therapeutic strategies for IBD. In this review article, we briefly introduce 74 kinds of genetically engineered mouse models that spontaneously develop intestinal inflammation. PMID:26387641

Natural killer cell lines preferentially kill clonogenic multiple myeloma cells and decrease myeloma engraftment in a bioluminescent xenograft mouse model

PubMed Central

Swift, Brenna E.; Williams, Brent A.; Kosaka, Yoko; Wang, Xing-Hua; Medin, Jeffrey A.; Viswanathan, Sowmya; Martinez-Lopez, Joaquin; Keating, Armand

2012-01-01

Background Novel therapies capable of targeting drug resistant clonogenic MM cells are required for more effective treatment of multiple myeloma. This study investigates the cytotoxicity of natural killer cell lines against bulk and clonogenic multiple myeloma and evaluates the tumor burden after NK cell therapy in a bioluminescent xenograft mouse model. Design and Methods The cytotoxicity of natural killer cell lines was evaluated against bulk multiple myeloma cell lines using chromium release and flow cytometry cytotoxicity assays. Selected activating receptors on natural killer cells were blocked to determine their role in multiple myeloma recognition. Growth inhibition of clonogenic multiple myeloma cells was assessed in a methylcellulose clonogenic assay in combination with secondary replating to evaluate the self-renewal of residual progenitors after natural killer cell treatment. A bioluminescent mouse model was developed using the human U266 cell line transduced to express green fluorescent protein and luciferase (U266eGFPluc) to monitor disease progression in vivo and assess bone marrow engraftment after intravenous NK-92 cell therapy. Results Three multiple myeloma cell lines were sensitive to NK-92 and KHYG-1 cytotoxicity mediated by NKp30, NKp46, NKG2D and DNAM-1 activating receptors. NK-92 and KHYG-1 demonstrated 2- to 3-fold greater inhibition of clonogenic multiple myeloma growth, compared with killing of the bulk tumor population. In addition, the residual colonies after treatment formed significantly fewer colonies compared to the control in a secondary replating for a cumulative clonogenic inhibition of 89–99% at the 20:1 effector to target ratio. Multiple myeloma tumor burden was reduced by NK-92 in a xenograft mouse model as measured by bioluminescence imaging and reduction in bone marrow engraftment of U266eGFPluc cells by flow cytometry. Conclusions This study demonstrates that NK-92 and KHYG-1 are capable of killing clonogenic and bulk multiple myeloma cells. In addition, multiple myeloma tumor burden in a xenograft mouse model was reduced by intravenous NK-92 cell therapy. Since multiple myeloma colony frequency correlates with survival, our observations have important clinical implications and suggest that clinical studies of NK cell lines to treat MM are warranted. PMID:22271890

Ethanol Extract of Haliclona sp. Improved Histological Grade of Mammary Adenocarcinoma in C3H Mice

NASA Astrophysics Data System (ADS)

Murwani, R.; Trianto, A.; Wijayanti, E.; Ridlo, A.; Susilaningsih, N.

2018-02-01

The sponge Haliclona sp. contains secondary metabolites belong to alkaloids which are cytotoxic to the human tumor. The following research was conducted to study the effect of a graded level of Haliclona sp. extract on mammary adenocarcinoma in C3H mice. Haliclona sp. was obtained from Bandengan water in Jepara, and the crude extract was prepared by maceration with ethanol. Fifteen C3H mice with an initial weight of 20-25 gram were assigned into control, H-1, and H-2 groups. Control, H1, and H2 groups each received the ethanol extract of 0, 0.15, and 1.5 mg per mouse per day respectively for two weeks. Cancer cells were introduced to all groups from a cancerous donor mouse. The donor cancer cells were injected into each mouse via left or right axilla and allowed to grow. The cancer mass was removed and processed for histological examination, and the cancer growth was determined according to Elston and Ellis criteria. The result showed that histological grade of cancer mass from control group was in grade 2 or differentiated moderately. The histological grade of cancer mass from H-1 and H-2 groups were in grade 1 or similar to a normal cell. Analyses of the data by Kruskal-Wallis showed a significant difference (p<0,05) between control and treated groups. No significant difference was found between H-1 and H-2 groups. The results suggest the potential of active substances in the ethanol extract of Haliclona sp as an anti-cancer drug.

Senescence of nickel-transformed cells by an X chromosome: Possible epigenetic control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, C.B.; Xin Wei Wang; Bhamra, R.K.

1991-02-15

Transfer of a normal Chinese hamster X chromosome (carried in a mouse A9 donor cell line) to a nickel-transformed Chinese hamster cell line with an Xq chromosome deletion resulted in senescense of these previously immortal cells. At early passages of the A9/CX donor cells, the hamster X chromosome was highly active, inducing senescence in 100% of the colonies obtained after its transfer into the nickel-transformed cells. However, senescence was reduced to 50% when Chinese hamster X chromosomes were transferred from later passage A9 cells. Full senescing activity of the intact hamster X chromosome was restored by treatment of the donormore » mouse cells with 5-azacytidine, which induced demethylation of DMA. These results suggest that a senescence gene or genes, which may be located on the Chinese hamster X chromosome, can be regulated by DNA methylation, and that escape from senescence and possibly loss of tumor suppressor gene activity can occur by epigenetic mechanisms.« less

T-Cell Mineralocorticoid Receptor Controls Blood Pressure by Regulating Interferon-Gamma.

PubMed

Sun, Xue-Nan; Li, Chao; Liu, Yuan; Du, Lin-Juan; Zeng, Meng-Ru; Zheng, Xiao-Jun; Zhang, Wu-Chang; Liu, Yan; Zhu, Mingjiang; Kong, Deping; Zhou, Li; Lu, Limin; Shen, Zhu-Xia; Yi, Yi; Du, Lili; Qin, Mu; Liu, Xu; Hua, Zichun; Sun, Shuyang; Yin, Huiyong; Zhou, Bin; Yu, Ying; Zhang, Zhiyuan; Duan, Sheng-Zhong

2017-05-12

Hypertension remains to be a global public health burden and demands novel intervention strategies such as targeting T cells and T-cell-derived cytokines. Mineralocorticoid receptor (MR) antagonists have been clinically used to treat hypertension. However, the function of T-cell MR in blood pressure (BP) regulation has not been elucidated. We aim to determine the role of T-cell MR in BP regulation and to explore the mechanism. Using T-cell MR knockout mouse in combination with angiotensin II-induced hypertensive mouse model, we demonstrated that MR deficiency in T cells strikingly decreased both systolic and diastolic BP and attenuated renal and vascular damage. Flow cytometric analysis showed that T-cell MR knockout mitigated angiotensin II-induced accumulation of interferon-gamma (IFN-γ)-producing T cells, particularly CD8 + population, in both kidneys and aortas. Similarly, eplerenone attenuated angiotensin II-induced elevation of BP and accumulation of IFN-γ-producing T cells in wild-type mice. In cultured CD8 + T cells, T-cell MR knockout suppressed IFN-γ expression whereas T-cell MR overexpression and aldosterone both enhanced IFN-γ expression. At the molecular level, MR interacted with NFAT1 (nuclear factor of activated T-cells 1) and activator protein-1 in T cells. Finally, T-cell MR overexpressing mice manifested more elevated BP compared with control mice after angiotensin II infusion and such difference was abolished by IFN-γ-neutralizing antibodies. MR may interact with NFAT1 and activator protein-1 to control IFN-γ in T cells and to regulate target organ damage and ultimately BP. Targeting MR in T cells specifically may be an effective novel approach for hypertension treatment. © 2017 American Heart Association, Inc.

Basilar membrane vibration after targeted removal of the third row of OHCs and Deiters cells

NASA Astrophysics Data System (ADS)

Xia, Anping; Udagawa, Tomokatsu; Raphael, Patrick D.; Cheng, Alan G.; Steele, Charles R.; Applegate, Brian E.; Oghalai, John S.

2018-05-01

The mammalian cochlea has three rows of outer hair cells (OHCs) that amplify the basilar membrane (BM) traveling wave with high gain and exquisite sharpness. However, it is unclear why three rows of OHCs are needed to achieve this. We used a novel transgenic mouse with the diphtheria toxin receptor in Lgr5-positive cells (Lgr5DTR-EGFP/+ mouse) that allowed us to ablate the third row of OHCs and Deiters cells (D) in adulthood via DT injection, after normal cochlear function had developed. We then used volumetric optical coherence tomography (VOCTV) to investigate the impacts of this manipulation of cochlear amplification in the apical turn. As expected, Lgr5DTR-EGFP/+ control mice had sharply-tuned vibratory responses. However, Lgr5DTR-EGFP/+ mice had broad tuning with a 20 dB increase in vibratory thresholds. The Q10dB was ˜1 in Lgr5DTR-EGFP/+ mice, whereas it was ˜3 in control mice. The characteristic frequency was lower in Lgr5DTR-EGFP/+ mice compared to controls (7.5 vs. 9.0 kHz). The gain of cochlear amplification was substantially lower in Lgr5DTR-EGFP/+ mice compared to controls (22 vs. 50). In the post-mortem period, the vibratory responses in Lgr5DTR-EGFP/+ mice were identical to controls. Together, these results demonstrate the substantial importance of the third row of OHCs and Deiters cells to normal cochlear amplification.

Mouse IgA inhibits cell growth by stimulating tumor necrosis factor-alpha production and apoptosis of macrophage cell lines.

PubMed

Reljic, Rajko; Crawford, Carol; Challacombe, Stephen; Ivanyi, Juraj

2004-04-01

Potent Fcalpha-mediated actions of IgA have previously been shown for myeloid cells from man, but much less is known in relation to murine cells. Here, we report that mouse monoclonal IgA, irrespective of their antigenic specificity, inhibit the proliferation of mouse macrophage cell lines. The anti-proliferative activity was manifested by both monomeric and polymeric mouse IgA, but not by mouse monoclonal IgG and IgM. Growth of J774 cells was significantly inhibited during the 4-8 days of logarithmic growth, followed by a subsequent recovery of cell numbers prior to the stationary phase. We demonstrated that IgA binds to J774 cells, stimulates tumor necrosis factor (TNF)-alpha production and induces apoptosis which is not dependent on NO or FAS/CD95. We also demonstrated that IgA, in synergy with IFN-gamma, induced TNF-alpha production and apoptosis of thioglycollate-elicited mouse peritoneal macrophages. Thus, the in vitro actions of IgA described may also play a regulatory role for mouse macrophages in vivo.

HBV life cycle is restricted in mouse hepatocytes expressing human NTCP.

PubMed

Li, Hanjie; Zhuang, Qiuyu; Wang, Yuze; Zhang, Tianying; Zhao, Jinghua; Zhang, Yali; Zhang, Junfang; Lin, Yi; Yuan, Quan; Xia, Ningshao; Han, Jiahuai

2014-03-01

Recent studies have revealed that human sodium taurocholate cotransporting polypeptide (SLC10A1 or NTCP) is a functional cellular receptor for hepatitis B virus (HBV). However, whether human NTCP can support HBV infection in mouse hepatocyte cell lines has not been clarified. Because an HBV-permissible mouse model would be helpful for the study of HBV pathogenesis, it is necessary to investigate whether human NTCP supports the susceptibility of mouse hepatocyte cell lines to HBV. The results show that exogenous human NTCP expression can render non-susceptible HepG2 (human), Huh7 (human), Hepa1-6 (mouse), AML-12 (mouse) cell lines and primary mouse hepatocyte (PMH) cells susceptible to hepatitis D virus (HDV) which employs HBV envelope proteins. However, human NTCP could only introduce HBV susceptibility in human-derived HepG2 and Huh7 cells, but not in mouse-derived Hepa1-6, AML-12 or PMH cells. These data suggest that although human NTCP is a functional receptor that mediates HBV infection in human cells, it cannot support HBV infection in mouse hepatocytes. Our study indicated that the restriction of HBV in mouse hepatocytes likely occurs after viral entry but prior to viral transcription. We have excluded the role of mouse hepatocyte nuclear factors in the restriction of the HBV life cycle and showed that knockdown or inhibition of Sting, TBK1, IRF3 or IRF7, the components of the anti-viral signaling pathways, had no effect on HBV infection in mouse hepatocytes. Therefore, murine restriction factors that limit HBV infection need to be identified before a HBV-permissible mouse line can be created.

Preimplantation death of xenomitochondrial mouse embryo harbouring bovine mitochondria

PubMed Central

Kawahara, Manabu; Koyama, Shiori; Iimura, Satomi; Yamazaki, Wataru; Tanaka, Aiko; Kohri, Nanami; Sasaki, Keisuke; Takahashi, Masashi

2015-01-01

Mitochondria, cellular organelles playing essential roles in eukaryotic cell metabolism, are thought to have evolved from bacteria. The organization of mtDNA is remarkably uniform across species, reflecting its vital and conserved role in oxidative phosphorylation (OXPHOS). Our objectives were to evaluate the compatibility of xenogeneic mitochondria in the development of preimplantation embryos in mammals. Mouse embryos harbouring bovine mitochondria (mtB-M embryos) were prepared by the cell-fusion technique employing the haemagglutinating virus of Japan (HVJ). The mtB-M embryos showed developmental delay at embryonic days (E) 3.5 after insemination. Furthermore, none of the mtB-M embryos could implant into the maternal uterus after embryo transfer, whereas control mouse embryos into which mitochondria from another mouse had been transferred developed as well as did non-manipulated embryos. When we performed quantitative PCR (qPCR) of mouse and bovine ND5, we found that the mtB-M embryos contained 8.3% of bovine mitochondria at the blastocyst stage. Thus, contamination with mitochondria from another species induces embryonic lethality prior to implantation into the maternal uterus. The heteroplasmic state of these xenogeneic mitochondria could have detrimental effects on preimplantation development, leading to preservation of species-specific mitochondrial integrity in mammals. PMID:26416548

Systemic administration of low dosage of tetanus toxin decreases cell proliferation and neuroblast differentiation in the mouse hippocampal dentate gyrus

PubMed Central

Yan, Bing Chun; Kim, In Hye; Park, Joon Ha; Ahn, Ji Hyeon; Cho, Jeong-Hwi; Chen, Bai Hui; Lee, Jae-Chul; Choi, Jung Hoon; Yoo, Ki-Yeon; Lee, Choong Hyun; Cho, Jun Hwi

2013-01-01

In the present study, we investigated the effect of Tetaus toxin (TeT) on cell proliferation and neuroblast differentiation using specific markers: 5-bromo-2-deoxyuridine (BrdU) as an exogenous marker for cell proliferation, Ki-67 as an endogenous marker for cell proliferation and doublecortin (DCX) as a marker for neuroblasts in the mouse hippocampal dentate gyrus (DG) after TeT treatment. Mice were intraperitoneally administered 2.5 and 10 ng/kg TeT and sacrificed 15 days after the treatment. In both the TeT-treated groups, no neuronal death occurred in any layers of the DG using neuronal nuclei (NeuN, a neuron nuclei maker) and Fluoro-Jade B (F-J B, a high-affinity fluorescent marker for the localization of neuronal degeneration). In addition, no significant change in glial activation in both the 2.5 and 10 ng/kg TeT-treated-groups was found by GFAP (a marker for astrocytes) and Iba-1 (a marker for microglia) immunohistochemistry. However, in the 2.5 ng/kg TeT-treated-group, the mean number of BrdU, Ki-67 and DCX immunoreactive cells, respectively, were apparently decreased compared to the control group, and the mean number of each in the 10 ng/kg TeT-treated-group was much more decreased. In addition, processes of DCX-immunoreactive cells, which projected into the molecular layer, were short compared to those in the control group. In brief, our present results show that low dosage (10 ng/kg) TeT treatment apparently decreased cell proliferation and neuroblast differentiation in the mouse hippocampal DG without distinct gliosis as well as any loss of adult neurons. PMID:24106509

ABT-510 induces tumor cell apoptosis and inhibits ovarian tumor growth in an orthotopic, syngeneic model of epithelial ovarian cancer

PubMed Central

Greenaway, James; Henkin, Jack; Lawler, Jack; Moorehead, Roger; Petrik, Jim

2012-01-01

Epithelial ovarian cancer (EOC) is the fifth most common cancer in women and is characterized by a low 5-year survival rate. One strategy that can potentially improve the overall survival rate in ovarian cancer is the use of antitumor agents such as ABT-510. ABT-510 is a small mimetic peptide of the naturally occurring antiangiogenic compound thrombospondin-1 and has been shown to significantly reduce tumor growth and burden in preclinical mouse models and in naturally occurring tumors in dogs. This is the first evaluation of ABT-510 in a preclinical model of human EOC. Tumorigenic mouse surface epithelial cells were injected into the bursa of C57BL/6 mice that were treated with either 100 mg/kg ABT-510 or an equivalent amount of PBS. ABT-510 caused a significant reduction in tumor size, ascites fluid volume, and secondary lesion dissemination when compared with PBS controls. Analysis of the vasculature of ABT-510-treated mice revealed vascular remodeling with smaller diameter vessels and lower overall area, increased number of mature vessels, and decreased tissue hypoxia. Tumors of ABT-510-treated mice had a significantly higher proportion of apoptotic tumor cells compared with the PBS-treated controls. Immunoblot analysis of cell lysates revealed a reduction in vascular endothelial growth factor, vascular endothelial growth factor receptor-2, and proliferating cell nuclear antigen protein expression as well as expression of members of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase survival pathways. In vitro, ABT-510 induced tumor cell apoptosis in mouse and human ovarian cancer cells. This study shows ABT-510 as a promising candidate for inhibiting tumor growth and ascites formation in human EOC. PMID:19139114

ABT-510 induces tumor cell apoptosis and inhibits ovarian tumor growth in an orthotopic, syngeneic model of epithelial ovarian cancer.

PubMed

Greenaway, James; Henkin, Jack; Lawler, Jack; Moorehead, Roger; Petrik, Jim

2009-01-01

Epithelial ovarian cancer (EOC) is the fifth most common cancer in women and is characterized by a low 5-year survival rate. One strategy that can potentially improve the overall survival rate in ovarian cancer is the use of antitumor agents such as ABT-510. ABT-510 is a small mimetic peptide of the naturally occurring antiangiogenic compound thrombospondin-1 and has been shown to significantly reduce tumor growth and burden in preclinical mouse models and in naturally occurring tumors in dogs. This is the first evaluation of ABT-510 in a preclinical model of human EOC. Tumorigenic mouse surface epithelial cells were injected into the bursa of C57BL/6 mice that were treated with either 100 mg/kg ABT-510 or an equivalent amount of PBS. ABT-510 caused a significant reduction in tumor size, ascites fluid volume, and secondary lesion dissemination when compared with PBS controls. Analysis of the vasculature of ABT-510-treated mice revealed vascular remodeling with smaller diameter vessels and lower overall area, increased number of mature vessels, and decreased tissue hypoxia. Tumors of ABT-510-treated mice had a significantly higher proportion of apoptotic tumor cells compared with the PBS-treated controls. Immunoblot analysis of cell lysates revealed a reduction in vascular endothelial growth factor, vascular endothelial growth factor receptor-2, and proliferating cell nuclear antigen protein expression as well as expression of members of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase survival pathways. In vitro, ABT-510 induced tumor cell apoptosis in mouse and human ovarian cancer cells. This study shows ABT-510 as a promising candidate for inhibiting tumor growth and ascites formation in human EOC.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Wenjing; Hao, Baixia; Wang, Qian

Extracellular signal-regulated kinases (ERKs) have been implicated to be dispensable for self-renewal of mouse embryonic stem (ES) cells, and simultaneous inhibition of both ERK signaling and glycogen synthase kinase 3 (GSK3) not only allows mouse ES cells to self-renew independent of extracellular stimuli but also enables more efficient derivation of naïve ES cells from mouse and rat strains. Interestingly, some ERKs stay active in mouse ES cells which are maintained in regular medium containing leukemia inhibitory factor (LIF) and bone morphogenetic protein (BMP). Yet, the upstream signaling for ERK activation and their roles in mouse ES cells, other than promotingmore » or priming differentiation, have not been determined. Here we found that mouse ES cells express three forms of Raf kinases, A-Raf, B-Raf, and C-Raf. Knocking-down each single Raf member failed to affect the sustained ERK activity, neither did A-Raf and B-Raf double knockdown or B-Raf and C-Raf double knockdown change it in ES cells. Interestingly, B-Raf and C-Raf double knockdown, not A-Raf and B-Raf knockdown, inhibited the maximal ERK activation induced by LIF, concomitant with the slower growth of ES cells. On the other hand, A-Raf, B-Raf, and C-Raf triple knockdown markedly inhibited both the maximal and sustained ERK activity in ES cells. Moreover, Raf triple knockdown, similar to the treatment of U-0126, an MEK inhibitor, significantly inhibited the survival and proliferation of ES cells, thereby compromising the colony propagation of mouse ES cells. In summary, our data demonstrate that all three Raf members are required for ERK activation in mouse ES cells and are involved in growth and survival of mouse ES cells. - Highlights: ●Mouse ES (mES) cells express all three Raf members, A-Raf, B-Raf, and C-Raf. ●Leukemia inhibitory factor (LIF) temporally activates ERKs in mES cells. ●B-Raf and C-Raf are required for LIF-induced maximal ERKs activity in mES cells. ●All Raf members are required for LIF-induced sustained ERK activity in mES cells. ●All Raf members are required the survival and proliferation of mES cells.« less

Characterization of the Kv channels of mouse carotid body chemoreceptor cells and their role in oxygen sensing

PubMed Central

Pérez-García, M Teresa; Colinas, Olaia; Miguel-Velado, Eduardo; Moreno-Domínguez, Alejandro; López-López, José Ramón

2004-01-01

As there are wide interspecies variations in the molecular nature of the O2-sensitive Kv channels in arterial chemoreceptors, we have characterized the expression of these channels and their hypoxic sensitivity in the mouse carotid body (CB). CB chemoreceptor cells were obtained from a transgenic mouse expressing green fluorescent protein (GFP) under the control of tyrosine hydroxylase (TH) promoter. Immunocytochemical identification of TH in CB cell cultures reveals a good match with GFP-positive cells. Furthermore, these cells show an increase in [Ca2+]i in response to low PO2, demonstrating their ability to engender a physiological response. Whole-cell experiments demonstrated slow-inactivating K+ currents with activation threshold around −30 mV and a bi-exponential kinetic of deactivation (τ of 6.24 ± 0.52 and 32.85 ± 4.14 ms). TEA sensitivity of the currents identified also two different components (IC50 of 17.8 ± 2.8 and 940.0 ± 14.7 μm). Current amplitude decreased reversibly in response to hypoxia, which selectively affected the fast deactivating component. Hypoxic inhibition was also abolished in the presence of low (10–50 μm) concentrations of TEA, suggesting that O2 interacts with the component of the current most sensitive to TEA. The kinetic and pharmacological profile of the currents suggested the presence of Kv2 and Kv3 channels as their molecular correlates, and we have identified several members of these two subfamilies by single-cell PCR and immunocytochemistry. This report represents the first functional and molecular characterization of Kv channels in mouse CB chemoreceptor cells, and strongly suggests that O2-sensitive Kv channels in this preparation belong to the Kv3 subfamily. PMID:15034123

Dual effects of fluoxetine on mouse early embryonic development.

PubMed

Kim, Chang-Woon; Choe, Changyong; Kim, Eun-Jin; Lee, Jae-Ik; Yoon, Sook-Young; Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee; Kang, Dawon

2012-11-15

Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50μM) for different durations. When late 2-cells were incubated with 5μM fluoxetine for 6h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5μM) over 24h showed a reduction in blastocyst formation. The addition of fluoxetine (5μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K(+) channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ~30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Copyright © 2012 Elsevier Inc. All rights reserved.

Exacerbation of Autoimmune Thyroiditis by CTLA-4 Blockade: A Role for IFNγ-Induced Indoleamine 2, 3-Dioxygenase

PubMed Central

Sharma, Rajni; Di Dalmazi, Giulia

2016-01-01

Background: Cytotoxic T-lymphocyte associated protein 4 (CTLA-4) is a negative regulator of immune responses that suppresses the activity of effector T cells and contributes to the maintenance of self tolerance. When blocked therapeutically, CTLA-4 leads to an overall activation of T cells that has been exploited for cancer control, a control associated however with a variety of immune-related side effects such as autoimmune thyroiditis. To investigate the mechanism(s) underlying this form of thyroiditis, we used the NOD-H2h4 mouse, a model that develops thyroiditis at very high incidence after addition of iodine to the drinking water. Methods: NOD-H2h4 mice were started on drinking water supplemented with 0.05% sodium iodide when 8 weeks old and then injected with a hamster monoclonal antibody against mouse CTLA-4, polyclonal hamster immunoglobulins, or phosphate buffered saline when 11 weeks old. One month later (15 weeks of age), mice were sacrificed to assess thyroiditis, general immune responses in blood and spleen, and expression of indoleamine 2, 3-dioxygenase (IDO) in the thyroid and in isolated antigen-presenting cells after stimulation with interferon gamma. The study also analyzed IDO expression in four autopsy cases of metastatic melanoma who had received treatment with a CTLA-4 blocking antibody, and six surgical pathology Hashimoto thyroiditis controls. Results: CTLA-4 blockade worsened autoimmune thyroiditis, as assessed by a greater incidence, a more aggressive mononuclear cell infiltration in thyroids, and higher thyroglobulin antibody levels when compared to the control groups. CTLA-4 blockade also expanded the proportion of splenic CD4+ effector T cells, as well as the production of interleukin (IL)-2, interferon gamma, IL-10, and IL-13 cytokines. Interestingly, CTLA-4 blockade induced a strong expression of IDO in mouse and human thyroid glands, an expression that could represent a counter-regulatory mechanism to protect against the inflammatory environment. Conclusions: This study shows that CTLA-4 blockade exacerbates the iodine-accelerated form of thyroiditis typical of the NOD-H2h4 mouse. The study could also have implications for cancer patients who develop thyroiditis as an immune-related adverse event after CTLA-4 blockade. PMID:27296629

Cyclic loading increases friction and changes cartilage surface integrity in lubricin-mutant mouse knees

PubMed Central

Drewniak, Elizabeth I; Jay, Gregory D; Fleming, Braden C; Zhang, Ling; Warman, Matthew L; Crisco, Joseph J

2012-01-01

Objective To investigate the effects of lubricin gene dosage and cyclic loading on whole joint coefficient of friction and articular cartilage surface integrity in mouse knee joints. Methods Joints from mice with 2 (Prg4+/+), 1 (Prg4+/−), or no (Prg4−/−) functioning lubricin alleles were subjected to 26 hours of cyclic loading using a custom-built pendulum. Coefficient of friction values were measured at multiple time points. Contralateral control joints were left unloaded. Following testing, joints were examined for histologic evidence of damage and cell viability. Results At baseline, the coefficient of friction values in Prg4−/− mice were significantly higher than those in Prg4+/+ and Prg4+/− mice (P < 0.001). Cyclic loading continuously increased the coefficient of friction in Prg4−/− mouse joints. In contrast, Prg4+/− and Prg4+/+ mouse joints had no coefficient of friction increases during the first 4 hours of loading. After 26 hours of loading, joints from all genotypes had increased coefficient of friction values compared to baseline and unloaded controls. Significantly greater increases occurred in Prg4−/− and Prg4+/− mouse joints compared to Prg4+/+ mouse joints. The coefficient of friction values were not significantly associated with histologic evidence of damage or loss of cell viability. Conclusion Our findings indicate that mice lacking lubricin have increased baseline coefficient of friction values and are not protected against further increases caused by loading. Prg4+/− mice are indistinguishable from Prg4+/+ mice at baseline, but have significantly greater coefficient of friction values following 26 hours of loading. Lubricin dosage affects joint properties during loading, and may have clinical implications in patients for whom injury or illness alters lubricin abundance. PMID:21905020

Somatic cell hybrid mapping on mouse chromosome 11 (MMU11): Assignment of markers relative to two breakpoints in band D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, D.J.; Robinson, T.J.; Adler, I.D.

1993-02-01

Mouse [times] rat somatic cell hybrids were generated by fusing mouse cell lines that are heterozygous for reciprocal translocations involving the T42H and T9Ad breakpoints on mouse chromosome 11 (MMU11) to a thymidine kinase-negative (Tk[sup [minus

[The therapeutic effect of HSV1-hGM-CSF combined with doxorubicin on the mouse breast cancer model].

PubMed

Zhuang, X F; Zhang, S R; Liu, B L; Wu, J L; Li, X Q; Gu, H G; Shu, Y

2018-03-23

Objective: To evaluate the oncolytic effect of herpes simplex virus type 1 which carried recombined human granulocyte-macrophage colony-stimulating factor (HSV1-hGM-CSF) on the mouse breast cancer cell line 4T1 and compare the anticancer effects of HSV1-hGM-CSF, doxorubicin alone or combination on the breast cancer in mice. Methods: We investigated the cytotoxic effect on 4T1 cells in vitro, the cell growth, cell apoptosis and cell cycle of 4T1 cells treated with oncolytic HSV1-hGM-CSF at different MOIs (0, 0.5, 1 and 2) and doxorubicin at different concentrations (0, 2, 4 and 8 μg/ml). The effects of oncolytic HSV1-hGM-CSF and doxorubicin on the tumor growth, survival time and their side effects on the mouse breast cancer model were observed. Results: Both oncolytic HSV1-hGM-CSF and doxorubicin significantly inhibited the proliferation of 4T1 cells in vitro . Doxorubicin induced the G(2)/M phase arrest of 4T1 cells, while the cytotoxicity of oncolytic HSV1-hGM-CSF was no cell cycle-dependent.At day 16 after treatment with doxorubicin and HSV1-hGM-CSF, the tumor volume of 4T1 tumor bearing mice were (144.40±27.68)mm(3,) (216.80±57.18)mm(3,) (246.10±21.90)mm(3,) (327.50±44.24)mm(3,) (213.30±32.31)mm(3) and (495.80±75.87)mm(3) in the groups of doxorubicin combined with high dose HSV1-hGM-CSF, doxorubicin combined with low dose HSV1-hGM-CSF, doxorubicin alone, high dose HSV1-hGM-CSF alone, low dose HSV1-hGM-CSF alone and control, respectively.Compared with the control group, both doxorubicin and HSV1-hGM-CSF treatment exhibited significant reduction of primary tumor volume in vivo ( P <0.001). The median survival times were 48, 50, 40, 42, 43 and 37 days in the six groups mentioned above, respectively. The median survival period of doxorubicin alone, high dose HSV1-hGM-CSF alone and low dose HSV1-hGM-CSF alone were significantly longer than that of control ( P <0.05). Conclusion: Synergistic effect of sequential treatment with doxorubicin and oncolytic HSV1-hGM-CSF is observed in 4T1 mouse breast cancer.

Hybridomas using athymic nude mouse injected with Crohn's disease (CD) tissue filtrate. Immunoreactivity of the hybridomas with CD sera.

PubMed Central

Das, K. M.; Vecchi, M.; Novikoff, A.; Mazumdar, S.; Novikoff, P. M.

1990-01-01

Injections of Crohn's disease (CD) tissue filtrates produce lymphoma and hyperplastic lymph nodes from plasma cell hyperplasia (PCH) in athymic nude (nu/nu) mice; these lymphoid tissue contain an antigen(s) recognized by CD serum/gamma G immunoglobulin (IgG). To immortalize the "CD-reactive antigen(s)," the authors fused the lymphoid cells from a CD tissue filtrate primed nu/nu mouse with nonsecretory mouse myeloma cells. Hybrids were screened and selected based on their reactivity with CD serum IgG, but not with control serum IgG in an indirect immunofluorescence assay (IF). Two CD-positive hybridomas were examined by IF with sera from 47 CD, 38 ulcerative colitis (UC), 13 controls with other gastrointestinal diseases, 19 with autoimmune diseases, and 21 normal subjects. Sera from 16 CD patients (34%) reacted with the two hybridomas, but only one of 38 UC sera and none of the 53 other disease or normal control sera reacted. The immunoreactivity of CD sera was significantly higher than UC sera (P less than 0.01) and each of the other groups (P less than 0.007). Using immunoperoxidase techniques at light and electron microscopic levels, the authors localized CD-associated antigen(s) in the plasma membrane of the two hybridomas. Further characterization of these hybridomas and the immunoreactive protein(s) may provide an important probe(s) for the diagnosis and the understanding of the pathogenesis of CD. Images Figure 2 Figure 3 PMID:2192559

Bone marrow-derived mesenchymal stem cells protect against lung injury in a mouse model of bronchopulmonary dysplasia.

PubMed

Luan, Yun; Ding, Wei; Ju, Zhi-Ye; Zhang, Zhao-Hua; Zhang, Xue; Kong, Feng

2015-03-01

The aim of the present study was to investigate the effect of bone marrow‑derived mesenchymal stem cells (BMSCs) in the treatment of lung injury in a mouse model of bronchopulmonary dysplasia (BPD) and examine the underlying mechanisms. A mouse model of BPD was created using continuous exposure to high oxygen levels for 14 days. BMSCs were isolated, cultured and then labeled with green fluorescent protein. Cells (1x106) were subsequently injected intravenously 1 h prior to high oxygen treatment. Animals were randomly divided into three groups (n=5 in each): Control group, BPD model group and BMSC injection group. At two weeks post‑treatment, the expression of transforming growth factor‑β1 (TGF‑β1), vascular endothelial growth factor (VEGF) and von Willebrand factor (vWF) was detected using immunohistochemical staining and immunofluorescence. Compared with the BPD model group, the body weight, airway structure and levels of TGF‑β1 and VEGF were significantly improved in the BMSC‑treated group. Immunofluorescence observations indicated that BMSCs were able to differentiate into cells expressing vWF and VEGF, which are markers of vascular tissues. The present study demonstrated that intravenous injection of BMSCs significantly improved lung damage in a neonatal mouse model of BPD at 14 days following hyperoxia‑induced injury. This provides novel information which may be used to guide further investigation into the use of stem cells in BPD.

Therapeutic effect of targeted Fas-expressing adenoviruses method combining γδ T cells in a mouse model of human ovarian carcinoma.

PubMed

Zeng, Dingyuan; Lin, Jiajing; He, Hongying; Tan, Guangping; Lan, Ying; Jiang, Fuyan; Sheng, Shuting

2018-02-01

The present study aimed to investigate the therapeutic effect and safety of targeted use of Fas-expressing adenoviruses combined with γδ T cell-mediated killing to treat human ovarian cancer xenografts in BALB/c mice. Shuttle plasmids containing control elements of human telomerase reverse transcriptase promoter and two-step transcriptional amplification system were constructed and packaged into adenovirus-5 vectors to generate expression of an exogenous Fas gene. A mouse xenograft model of human ovarian carcinoma was constructed. A total of 35 BALB/c mice were randomly divided into five groups, which were injected with PBS, γδ T cells, Fas-expressing adenoviruses, taxol, or Fas-expressing adenovirus and γδ T cells. The weight and volume of tumors in mice in each group was monitored. Tissue sections of the various tissues of mice in the Fas-expressing adenovirus and γδ T cells group was compared with those in the PBS group to evaluate the safety of Fas-expressing adenovirus and γδ T cells in the treatment of human ovarian cancer xenograft tumors. The results of the present study indicated that mice in all treatment groups were alive at the end of the treatment course. Tumor weight and volume was the highest in the PBS group, followed successively by the adenovirus group, the γδ T cell group, the adenovirus and γδ T cell group, and the taxol group. The weight and volume inhibition rate in adenovirus and γδ T cell group were significantly higher compared with in the PBS group (P<0.05). Pathological observation of tissue samples revealed that none of vital organs in the adenovirus and γδ T cell group developed any evident morphological changes during treatment, when compared with healthy controls. In conclusion, the combined therapy with Fas-expressing adenoviruses and γδ T cells is efficient and safe for the treatment of mouse human ovarian carcinoma xenografts.

Anticancer activity of streptochlorin, a novel antineoplastic agent, in cholangiocarcinoma

PubMed Central

Kwak, Tae Won; Shin, Hee Jae; Jeong, Young-Il; Han, Myoung-Eun; Oh, Sae-Ock; Kim, Hyun-Jung; Kim, Do Hyung; Kang, Dae Hwan

2015-01-01

Background The aim of this study is to investigate the anticancer activity of streptochlorin, a novel antineoplastic agent, in cholangiocarcinoma. Methods The anticancer activity of streptochlorin was evaluated in vitro in various cholangiocarcinoma cell lines for apoptosis, proliferation, invasiveness, and expression of various protein levels. A liver metastasis model was prepared by splenic injection of HuCC-T1 cholangiocarcinoma cells using a BALB/c nude mouse model to study the systemic antimetastatic efficacy of streptochlorin 5 mg/kg at 8 weeks. The antitumor efficacy of subcutaneously injected streptochlorin was also assessed using a solid tumor xenograft model of SNU478 cells for 22 days in the BALB/c nude mouse. Results Streptochlorin inhibited growth and secretion of vascular endothelial growth factor by cholangiocarcinoma cells in a dose-dependent manner and induced apoptosis in vitro. In addition, streptochlorin effectively inhibited invasion and migration of cholangiocarcinoma cells. Secretion of vascular endothelial growth factor and activity of matrix metalloproteinase-9 in cholangiocarcinoma cells were also suppressed by treatment with streptochlorin. Streptochlorin effectively regulated metastasis of HuCC-T1 cells in a mouse model of liver metastasis. In a tumor xenograft study using SNU478 cells, streptochlorin significantly inhibited tumor growth without changes in body weight when compared with the control. Conclusion These results reveal that streptochlorin is a promising chemotherapeutic agent to the treatment of cholangiocarcinoma. PMID:25931814

Three-dimensional reconstruction of tetraploid↔diploid chimaeric mouse blastocysts

PubMed Central

EVERETT, CLARE A.; STARK, MARGARET H.; WEST, JOHN D.; DAVIDSON, DUNCAN; BALDOCK, RICHARD A.

2000-01-01

Studies of tetraploid↔diploid (4n↔2n) mouse chimaeras have demonstrated unequal contributions of 4n cells to different tissues of the midgestation conceptus. Such a pattern has also been reported in chimaeras as early as E3.5d, which show an enhanced contribution of 4n cells to the mural trophectoderm (Everett & West, 1996). In this study, sectioned 4n↔2n and 2n↔2n control chimaeric blastocysts were digitised and reconstructed in 3 dimensions (3-D). The 3-D images revealed only limited mixing of cells from the 2 contributing embryos of individual blastocysts in both chimaera groups. Consequently, the distribution pattern of the 2 cell types was dependent on the spatial relationship between the orientation of the blastocyst and the boundary between the 2 clusters of cells. The distribution patterns observed were not strikingly different for 4n↔2n and 2n↔2n chimaeras, each showing some transgenic positive cell contribution in all 3 identifiable developmental lineages. It was notable, however, that in all 4n↔2n blastocysts at least some 4n cells were located adjacent to the blastocyst cavity. Such a consistent pattern was not evident in 2n↔2n chimaeras. This study has demonstrated the value of 3-D reconstructions for the analysis of spatial relationships of 2 cell populations in chimaeric mouse blastocysts. PMID:10853956

Cloning and expression of porcine Colony Stimulating Factor-1 (CSF-1) and Colony Stimulating Factor-1 Receptor (CSF-1R) and analysis of the species specificity of stimulation by CSF-1 and Interleukin 34

PubMed Central

Gow, Deborah J.; Garceau, Valerie; Kapetanovic, Ronan; Sester, David P.; Fici, Greg J.; Shelly, John A.; Wilson, Thomas L.; Hume, David A.

2012-01-01

Macrophage Colony Stimulating Factor (CSF-1) controls the survival, differentiation and proliferation of cells of the mononuclear phagocyte system. A second ligand for the CSF-1R, Interleukin 34 (IL-34), has been described, but its physiological role is not yet known. The domestic pig provides an alternative to traditional rodent models for evaluating potential therapeutic applications of CSF-1R agonists and antagonists. To enable such studies, we cloned and expressed active pig CSF-1. To provide a bioassay, pig CSF-1R was expressed in the factor-dependent Ba/F3 cell line. On this transfected cell line, recombinant porcine CSF-1 and human CSF-1 had identical activity. Mouse CSF-1 does not interact with the human CSF-1 receptor but was active on pig. By contrast, porcine CSF-1 was active on mouse, human, cat and dog cells. IL-34 was previously shown to be species-specific, with mouse and human proteins demonstrating limited cross-species activity. The pig CSF-1R was equally responsive to both mouse and human IL-34. Based upon the published crystal structures of CSF-1/CSF-1R and IL34/CSF-1R complexes, we discuss the molecular basis for the species specificity. PMID:22974529

HSC extrinsic sex-related and intrinsic autoimmune disease-related human B-cell variation is recapitulated in humanized mice.

PubMed

Borsotti, Chiara; Danzl, Nichole M; Nauman, Grace; Hölzl, Markus A; French, Clare; Chavez, Estefania; Khosravi-Maharlooei, Mohsen; Glauzy, Salome; Delmotte, Fabien R; Meffre, Eric; Savage, David G; Campbell, Sean R; Goland, Robin; Greenberg, Ellen; Bi, Jing; Satwani, Prakash; Yang, Suxiao; Bathon, Joan; Winchester, Robert; Sykes, Megan

2017-10-24

B cells play a major role in antigen presentation and antibody production in the development of autoimmune diseases, and some of these diseases disproportionally occur in females. Moreover, immune responses tend to be stronger in female vs male humans and mice. Because it is challenging to distinguish intrinsic from extrinsic influences on human immune responses, we used a personalized immune (PI) humanized mouse model, in which immune systems were generated de novo from adult human hematopoietic stem cells (HSCs) in immunodeficient mice. We assessed the effect of recipient sex and of donor autoimmune diseases (type 1 diabetes [T1D] and rheumatoid arthritis [RA]) on human B-cell development in PI mice. We observed that human B-cell levels were increased in female recipients regardless of the source of human HSCs or the strain of immunodeficient recipient mice. Moreover, mice injected with T1D- or RA-derived HSCs displayed B-cell abnormalities compared with healthy control HSC-derived mice, including altered B-cell levels, increased proportions of mature B cells and reduced CD19 expression. Our study revealed an HSC-extrinsic effect of recipient sex on human B-cell reconstitution. Moreover, the PI humanized mouse model revealed HSC-intrinsic defects in central B-cell tolerance that recapitulated those in patients with autoimmune diseases. These results demonstrate the utility of humanized mouse models as a tool to better understand human immune cell development and regulation.

Specificity and Heterogeneity of Terahertz Radiation Effect on Gene Expression in Mouse Mesenchymal Stem Cells

DOE PAGES

Alexandrov, Boian S.; Phipps, M. Lisa; Alexandrov, Ludmil B.; ...

2013-01-31

In this paper, we report that terahertz (THz) irradiation of mouse mesenchymal stem cells (mMSCs) with a single-frequency (SF) 2.52 THz laser or pulsed broadband (centered at 10 THz) source results in irradiation specific heterogenic changes in gene expression. The THz effect depends on irradiation parameters such as the duration and type of THz source, and on the degree of stem cell differentiation. Our microarray survey and RT-PCR experiments demonstrate that prolonged broadband THz irradiation drives mMSCs toward differentiation, while 2-hour irradiation (regardless of THz sources) affects genes transcriptionally active in pluripotent stem cells. The strictly controlled experimental environment indicatesmore » minimal temperature changes and the absence of any discernable response to heat shock and cellular stress genes imply a non-thermal response. Computer simulations of the core promoters of two pluripotency markers reveal association between gene upregulation and propensity for DNA breathing. Finally, we propose that THz radiation has potential for non-contact control of cellular gene expression.« less

Effects of Dai-kenchu-to on spontaneous activity in the mouse small intestine.

PubMed

Kito, Yoshihiko; Suzuki, Hikaru

2006-12-01

The effects of Dai-kenchu-to (DKT), a Chinese medicine, on spontaneous activity of mouse small intestine were investigated. Experiments were carried out with tension recording and intracellular recording. DKT contracted mouse longitudinal smooth muscles in a dose dependent manner (0.1-10 mg/ml). Low concentration of DKT (0.1 mg/ml) did not contract the longitudinal muscles of mouse small intestine. DKT (0.1 mg/ml) inhibited contraction elicited by transmural nerve stimulation (TNS). DKT (1 mg/ml) evoked relaxation before contraction. The initial relaxation was abolished by Nomega-nitro-L-arginine (L-NNA). DKT (10 mg/ml)-induced contraction had two components: a transient rapid contraction and a following slow contraction. Atropine inhibited DKT (1 mg/ml)-induced contraction to about 50% of control. In the presence of atropine, tetrodotoxin (TTX) inhibited the contraction elicited by DKT (1 mg/ml) to about 80%. DKT depolarized the membrane and decreased the amplitude of pacemaker potentials recorded from in situ myenteric interstitial cells of Cajal (ICC-MY) with no alteration to the frequency, duration and maximum rates of rise in the presence of nifedipine and TTX. The same results were obtained in slow waves recorded from circular smooth muscle cells. These results indicate that DKT evoked both contraction and relaxation by releasing acetylcholine, nitric oxide and other excitatory neurotransmitters in mouse small intestine. DKT had no effects on pacemaker mechanisms and electrical coupling between ICC-MY and smooth muscle cells in mouse small intestine. The results also suggest that DKT may contract smooth muscles by depolarizing the membrane directly.

Development of experimental tumors formed by mouse and human embryonic stem and teratocarcinoma cells after subcutaneous and intraperitoneal transplantations into immunodeficient and immunocompetent mice.

PubMed

Gordeeva, O F; Nikonova, T M

2013-01-01

Pluripotent stem cells represent an attractive cell source for regenerative medicine. However, the risk of teratoma formation after transplantation restricts their clinical application. Therefore, to adequately evaluate the potential risk of tumorigenicity after cell transplantation into human tissues, effective animal transplantation assays need to be developed. We performed a multiparameter (cell number, transplantation site, cell type, host) comparative analysis of the efficiency of tumor development after transplantation of mouse and human embryonic stem (ES) cells and their malignant counterparts, teratocarcinoma (EC) cells, into animal recipients and revealed several key correlations. We found that the efficiency of tumor growth was higher after intraperitoneal than after subcutaneous transplantations of all cell lines studied. The minimal cell numbers sufficient for tumor growth in immunodeficient nude mice were 100-fold lower for intraperitoneal than for subcutaneous transplantations of mouse and human ES cells (10(3) vs. 10(5) and 10(4) vs. 10(6), respectively). Moreover, mouse ES and EC cells formed tumors in immunodeficient and immunocompetent mice more effectively than human ES and EC cells. After intraperitoneal transplantation of 10(3), 10(4), and 10(5) mouse ES cells, teratomas developed in 83%, 100%, and 100% of nude mice, whereas after human ES cell transplantation, teratomas developed in 0%, 17%, and 60%, respectively. In addition, malignant mouse and human EC cells initiated tumor growth after intraperitoneal transplantation significantly faster and more effectively than ES cells. Mouse and human ES cells formed different types of teratomas containing derivatives of three germ layers but different numbers of undifferentiated cells. ES cell-like sublines with differentiation potential similar to the parental cell line were recloned only from mouse, but not from human, ES cell teratomas. These findings provide new information about the possibility and efficiency of tumor growth after transplantation of pluripotent stem cells. This information allows one to predict and possibly prevent the possible risks of tumorigenicity that could arise from stem cell therapeutics.

Insights into the role of Bcl6 in follicular Th cells using a new conditional mutant mouse model.

PubMed

Hollister, Kristin; Kusam, Saritha; Wu, Hao; Clegg, Ninah; Mondal, Arpita; Sawant, Deepali V; Dent, Alexander L

2013-10-01

The transcriptional repressor Bcl6 controls development of the follicular Th cell (T(FH)) lineage, but the precise mechanisms by which Bcl6 regulates this process are unclear. A model has been proposed whereby Bcl6 represses the differentiation of T cells into alternative effector lineages, thus favoring T(FH) cell differentiation. Analysis of T cell differentiation using Bcl6-deficient mice has been complicated by the strong proinflammatory phenotype of Bcl6-deficient myeloid cells. In this study, we report data from a novel mouse model where Bcl6 is conditionally deleted in T cells (Bcl6(fl/fl)Cre(CD4) mice). After immunization, programmed death -1 (PD-1)(high) T(FH) cells in Bcl6(fl/fl)Cre(CD4) mice are decreased >90% compared with control mice, and Ag-specific IgG is sharply reduced. Residual PD-1(high)CXCR5(+) T(FH) cells in Bcl6(fl/fl)Cre(CD4) mice show a significantly higher rate of apoptosis than do PD-1(high)CXCR5(+) T(FH) cells in control mice. Immunization of Bcl6(fl/fl)Cre(CD4) mice did not reveal enhanced differentiation into Th1, Th2, or Th17 lineages, although IL-10 expression by CD4 T cells was markedly elevated. Thus, T cell-extrinsic factors appear to promote the increased Th1, Th2, and Th17 responses in germline Bcl6-deficient mice. Furthermore, IL-10 may be a key target gene for Bcl6 in CD4 T cells, which enables Bcl6 to promote the T(FH) cell phenotype. Finally, our data reveal a novel mechanism for the role of Bcl6 in promoting T(FH) cell survival.

Heterophilic binding of the adhesion molecules poliovirus receptor and immunoglobulin superfamily 4A in the interaction between mouse spermatogenic and Sertoli cells.

PubMed

Wakayama, Tomohiko; Sai, Yoshimichi; Ito, Akihiko; Kato, Yukio; Kurobo, Miho; Murakami, Yoshinori; Nakashima, Emi; Tsuji, Akira; Kitamura, Yukihiko; Iseki, Shoichi

2007-06-01

The cell adhesion protein immunoglobulin superfamily 4A (IGSF4A) is expressed on the surfaces of spermatogenic cells in the mouse testis. During spermatogenesis, IGSF4A is considered to bind to the surface of Sertoli cells in a heterophilic manner. To identify this unknown partner of IGSF4A, we generated rat monoclonal antibodies against the membrane proteins of mouse Sertoli cells grown in primary culture. Using these monoclonal antibodies, we isolated a clone that immunostained Sertoli cells and reacted with the product of immunoprecipitation of the homogenate of mouse testis with anti-IGSF4A antibody. Subsequently, to identify the Sertoli cell membrane protein that is recognized by this monoclonal antibody, we performed expression cloning of a cDNA library from the mouse testis. As a result, we identified poliovirus receptor (PVR), which is another IGSF-type cell adhesion molecule, as the binding partner of IGSF4A. The antibodies raised against PVR and IGSF4A immunoprecipitated both antigens in the homogenate of mouse testis. Immunoreactivity for PVR was present in Sertoli cells but not in spermatogenic cells at all stages of spermatogenesis. Overexpression of PVR in TM4, a mouse Sertoli cell line, increased more than three-fold its capacity to adhere to Tera-2, which is a human cell line that expresses IGSF4A. These findings suggest that the heterophilic binding of PVR to IGSF4A is responsible, at least in part, for the interaction between Sertoli and spermatogenic cells during mouse spermatogenesis.

The bcl-2 knockout mouse exhibits marked changes in osteoblast phenotype and collagen deposition in bone as well as a mild growth plate phenotype

PubMed Central

BOOT-HANDFORD, R. P.; MICHAELIDIS, T. M.; HILLARBY, M. C.; ZAMBELLI, A.; DENTON, J.; HOYLAND, J. A.; FREEMONT, A. J.; GRANT, M. E.; WALLIS, G. A.

1998-01-01

Histological examination of long bones from 1-day-old bcl-2 knockout and age-matched control mice revealed no obvious differences in length of bone, growth plate architecture or stage of endochondral ossification. In 35-day-old bcl-2 knockout mice that are growth retarded or ‘dwarfed’, the proliferative zone of the growth plate appeared slightly thinner and the secondary centres of ossification less well developed than their age-matched wild-type controls. The most marked histological effects of bcl-2 ablation were on osteoblasts and bone. 35-day-old knockout mouse bones exhibited far greater numbers of osteoblasts than controls and the osteoblasts had a cuboidal phenotype in comparison with the normal flattened cell appearance. In addition, the collagen deposited by the osteoblasts in the bcl-2 knockout mouse bone was disorganized in comparison with control tissue and had a pseudo-woven appearance. The results suggest an important role for Bcl-2 in controlling osteoblast phenotype and bone deposition in vivo. PMID:10193316

ATR localizes to the photoreceptor connecting cilium and deficiency leads to severe photoreceptor degeneration in mice.

PubMed

Valdés-Sánchez, Lourdes; De la Cerda, Berta; Diaz-Corrales, Francisco J; Massalini, Simone; Chakarova, Christina F; Wright, Alan F; Bhattacharya, Shomi S

2013-04-15

Ataxia-telangiectasia and Rad3 (ATR), a sensor of DNA damage, is associated with the regulation and control of cell division. ATR deficit is known to cause Seckel syndrome, characterized by severe proportionate short stature and microcephaly. We used a mouse model for Seckel disease to study the effect of ATR deficit on retinal development and function and we have found a new role for ATR, which is critical for the postnatal development of the photoreceptor (PR) layer in mouse retina. The structural and functional characterization of the ATR(+/s) mouse retinas displayed a specific, severe and early degeneration of rod and cone cells resembling some characteristics of human retinal degenerations. A new localization of ATR in the cilia of PRs and the fact that mutant mice have shorter cilia suggests that the PR degeneration here described results from a ciliary defect.

Effect of whole-body irradiation of mice on the number of background plaque-forming cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, R.E.; Lefkovits, I.; Soeederberg, A.

1983-08-01

Mice were exposed in whole-body fashion to several doses of radiation and killed at various times thereafter for a determination of the number of background plaque-forming cells (PFCs) as assayed on either sheep erythrocytes or bromelain-treated autologous mouse erythrocytes. Increased numbers of both types of PFC were found in the irradiated groups. These increases were dependent on radiation dose and time after exposure. They did not appear to be caused by a disruption of normal lymphocyte traffic or a switch in immunoglobulin isotype. An increased number of PFCs on bromelain-treated mouse RBCs but not on sheep RBCs were found inmore » irradiated congenitally athymic nude mice. On the basis of this and related observations, background PFCs on bromelain-treated mouse RBCs and on sheep RBCs appear to fall under different forms of homeostatic control.« less

The replication of a mouse adapted SARS-CoV in a mouse cell line stably expressing the murine SARS-CoV receptor mACE2 efficiently induces the expression of proinflammatory cytokines

PubMed Central

Regla-Nava, Jose A.; Jimenez-Guardeño, Jose M.; Nieto-Torres, Jose L.; Gallagher, Thomas M.; Enjuanes, Luis; DeDiego, Marta L.

2013-01-01

Infection of conventional mice with a mouse adapted (MA15) severe acute respiratory syndrome (SARS) coronavirus (CoV) reproduces many aspects of human SARS such as pathological changes in lung, viremia, neutrophilia, and lethality. However, established mouse cell lines highly susceptible to mouse-adapted SARS-CoV infection are not available. In this work, efficiently transfectable mouse cell lines stably expressing the murine SARS-CoV receptor angiotensin converting enzyme 2 (ACE2) have been generated. These cells yielded high SARS-CoV-MA15 titers and also served as excellent tools for plaque assays. In addition, in these cell lines, SARS-CoV-MA15 induced the expression of proinflammatory cytokines and IFN-β, mimicking what has been observed in experimental animal models infected with SARS-CoV and SARS patients. These cell lines are valuable tools to perform in vitro studies in a mouse cell system that reflects the species used for in vivo studies of SARS-CoV-MA15 pathogenesis. PMID:23911968

Effects of hanging drop culture conditions on embryoid body formation and neuronal cell differentiation using mouse embryonic stem cells: optimization of culture conditions for the formation of well-controlled embryoid bodies.

PubMed

Ohnuki, Yoshitsugu; Kurosawa, Hiroshi

2013-05-01

Hanging drop (HD) cultures were carried out with a drop volume of either 20 or 30 μl. An incubation period of 3 days was determined to be appropriate for the formation of well-controlled embryoid bodies (EBs), and the initial cell number was identified as the most critical factor in the growth and neuronal cell differentiation of EBs. Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Tropomodulin1 is required for membrane skeleton organization and hexagonal geometry of fiber cells in the mouse lens

PubMed Central

Nowak, Roberta B.; Fischer, Robert S.; Zoltoski, Rebecca K.; Kuszak, Jerome R.

2009-01-01

Hexagonal packing geometry is a hallmark of close-packed epithelial cells in metazoans. Here, we used fiber cells of the vertebrate eye lens as a model system to determine how the membrane skeleton controls hexagonal packing of post-mitotic cells. The membrane skeleton consists of spectrin tetramers linked to actin filaments (F-actin), which are capped by tropomodulin1 (Tmod1) and stabilized by tropomyosin (TM). In mouse lenses lacking Tmod1, initial fiber cell morphogenesis is normal, but fiber cell hexagonal shapes and packing geometry are not maintained as fiber cells mature. Absence of Tmod1 leads to decreased γTM levels, loss of F-actin from membranes, and disrupted distribution of β2-spectrin along fiber cell membranes. Regular interlocking membrane protrusions on fiber cells are replaced by irregularly spaced and misshapen protrusions. We conclude that Tmod1 and γTM regulation of F-actin stability on fiber cell membranes is critical for the long-range connectivity of the spectrin–actin network, which functions to maintain regular fiber cell hexagonal morphology and packing geometry. PMID:19752024

MOLECULAR ANALYSIS OF MUTATIONS INDUCED BY MUTAGENS IN THE TK GENE OF MOUSE LYMPHOMA CELLS

EPA Science Inventory

MOLECULAR ANALYSIS OF MUTATIONS INDUCED BY BROMATE AND N- ETHYL-N-NITROSOUREA IN THE TK GENE OF MOUSE L YMPHOMA CELLS

The mouse lymphoma assay is widely used to identify chemical mutagens The Tk +1- gene located on an autosome in mouse lymphoma cells may recover a wide ra...

PTEN and PI-3 kinase inhibitors control LPS signaling and the lymphoproliferative response in the CD19+ B cell compartment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Alok R.; Peirce, Susan K.; Joshi, Shweta

Pattern recognition receptors (PRRs), e.g. toll receptors (TLRs) that bind ligands within the microbiome have been implicated in the pathogenesis of cancer. LPS is a ligand for two TLR family members, TLR4 and RP105 which mediate LPS signaling in B cell proliferation and migration. Although LPS/TLR/RP105 signaling is well-studied; our understanding of the underlying molecular mechanisms controlling these PRR signaling pathways remains incomplete. Previous studies have demonstrated a role for PTEN/PI-3K signaling in B cell selection and survival, however a role for PTEN/PI-3K in TLR4/RP105/LPS signaling in the B cell compartment has not been reported. Herein, we crossed a CD19cremore » and PTEN{sup fl/fl} mouse to generate a conditional PTEN knockout mouse in the CD19+ B cell compartment. These mice were further crossed with an IL-14α transgenic mouse to study the combined effect of PTEN deletion, PI-3K inhibition and expression of IL-14α (a cytokine originally identified as a B cell growth factor) in CD19+ B cell lymphoproliferation and response to LPS stimulation. Targeted deletion of PTEN and directed expression of IL-14α in the CD19+ B cell compartment (IL-14+PTEN-/-) lead to marked splenomegaly and altered spleen morphology at baseline due to expansion of marginal zone B cells, a phenotype that was exaggerated by treatment with the B cell mitogen and TLR4/RP105 ligand, LPS. Moreover, LPS stimulation of CD19+ cells isolated from these mice display increased proliferation, augmented AKT and NFκB activation as well as increased expression of c-myc and cyclinD1. Interestingly, treatment of LPS treated IL-14+PTEN-/- mice with a pan PI-3K inhibitor, SF1126, reduced splenomegaly, cell proliferation, c-myc and cyclin D1 expression in the CD19+ B cell compartment and normalized the splenic histopathologic architecture. These findings provide the direct evidence that PTEN and PI-3K inhibitors control TLR4/RP105/LPS signaling in the CD19+ B cell compartment and that pan PI-3 kinase inhibitors reverse the lymphoproliferative phenotype in vivo. - Highlights: • First genetic evidence that PTEN controls LPS/TLR4 signaling in B lymphocytes. • Evidence that PTEN regulates LPS induced lymphoproliferation in vivo. • PI-3 kinase inhibitors block LPS induced lymphoproliferation in vivo.« less

Mouse oocytes nucleoli rescue embryonic development of porcine enucleolated oocytes.

PubMed

Morovic, Martin; Strejcek, Frantisek; Nakagawa, Shoma; Deshmukh, Rahul S; Murin, Matej; Benc, Michal; Fulka, Helena; Kyogoku, Hirohisa; Pendovski, Lazo; Fulka, Josef; Laurincik, Jozef

2017-12-01

It is well known that nucleoli of fully grown mammalian oocytes are indispensable for embryonic development. Therefore, the embryos originated from previously enucleolated (ENL) oocytes undergo only one or two cleavages and then their development ceases. In our study the interspecies (mouse/pig) nucleolus transferred embryos (NuTE) were produced and their embryonic development was analyzed by autoradiography, transmission electron microscopy (TEM) and immunofluorescence (C23 and upstream binding factor (UBF)). Our results show that the re-injection of isolated oocyte nucleoli, either from the pig (P + P) or mouse (P + M), into previously enucleolated and subsequently matured porcine oocytes rescues their development after parthenogenetic activation and some of these develop up to the blastocyst stage (P + P, 11.8%; P + M, 13.5%). In nucleolus re-injected 8-cell and blastocyst stage embryos the number of nucleoli labeled with C23 in P + P and P + M groups was lower than in control (non-manipulated) group. UBF was localized in small foci within the nucleoli of blastocysts in control and P + P embryos, however, in P + M embryos the labeling was evenly distributed in the nucleoplasm. The TEM and autoradiographic evaluations showed the formation of functional nucleoli and de novo rRNA synthesis at the 8-cell stage in both, control and P + P group. In the P + M group the formation of comparable nucleoli was delayed. In conclusion, our results indicate that the mouse nucleolus can rescue embryonic development of enucleolated porcine oocytes, but the localization of selected nucleolar proteins, the timing of transcription activation and the formation of the functional nucleoli in NuTE compared with control group show evident aberrations.

Human mammary microenvironment better regulates the biology of human breast cancer in humanized mouse model.

PubMed

Zheng, Ming-Jie; Wang, Jue; Xu, Lu; Zha, Xiao-Ming; Zhao, Yi; Ling, Li-Jun; Wang, Shui

2015-02-01

During the past decades, many efforts have been made in mimicking the clinical progress of human cancer in mouse models. Previously, we developed a human breast tissue-derived (HB) mouse model. Theoretically, it may mimic the interactions between "species-specific" mammary microenvironment of human origin and human breast cancer cells. However, detailed evidences are absent. The present study (in vivo, cellular, and molecular experiments) was designed to explore the regulatory role of human mammary microenvironment in the progress of human breast cancer cells. Subcutaneous (SUB), mammary fat pad (MFP), and HB mouse models were developed for in vivo comparisons. Then, the orthotopic tumor masses from three different mouse models were collected for primary culture. Finally, the biology of primary cultured human breast cancer cells was compared by cellular and molecular experiments. Results of in vivo mouse models indicated that human breast cancer cells grew better in human mammary microenvironment. Cellular and molecular experiments confirmed that primary cultured human breast cancer cells from HB mouse model showed a better proliferative and anti-apoptotic biology than those from SUB to MFP mouse models. Meanwhile, primary cultured human breast cancer cells from HB mouse model also obtained the migratory and invasive biology for "species-specific" tissue metastasis to human tissues. Comprehensive analyses suggest that "species-specific" mammary microenvironment of human origin better regulates the biology of human breast cancer cells in our humanized mouse model of breast cancer, which is more consistent with the clinical progress of human breast cancer.

Targeted taste cell-specific overexpression of brain-derived neurotrophic factor in adult taste buds elevates phosphorylated TrkB protein levels in taste cells, increases taste bud size, and promotes gustatory innervation.

PubMed

Nosrat, Irina V; Margolskee, Robert F; Nosrat, Christopher A

2012-05-11

Brain-derived neurotrophic factor (BDNF) is the most potent neurotrophic factor in the peripheral taste system during embryonic development. It is also expressed in adult taste buds. There is a lack of understanding of the role of BDNF in the adult taste system. To address this, we generated novel transgenic mice in which transgene expression was driven by an α-gustducin promoter coupling BDNF expression to the postnatal expression of gustducin in taste cells. Immunohistochemistry revealed significantly stronger BDNF labeling in taste cells of high BDNF-expressing mouse lines compared with controls. We show that taste buds in these mice are significantly larger and have a larger number of taste cells compared with controls. To examine whether innervation was affected in Gust-BDNF mice, we used antibodies to neural cell adhesion molecule (NCAM) and ATP receptor P2X3. The total density of general innervation and specifically the gustatory innervation was markedly increased in high BDNF-expressing mice compared with controls. TrkB and NCAM gene expression in laser capture microdissected taste epithelia were significantly up-regulated in these mice. Up-regulation of TrkB transcripts in taste buds and elevated taste cell-specific TrkB phosphorylation in response to increased BDNF levels indicate that BDNF controls the expression and activation of its high affinity receptor in taste cells. This demonstrates a direct taste cell function for BDNF. BDNF also orchestrates and maintains taste bud innervation. We propose that the Gust-BDNF transgenic mouse models can be employed to further dissect the specific roles of BDNF in the adult taste system.

Targeted Taste Cell-specific Overexpression of Brain-derived Neurotrophic Factor in Adult Taste Buds Elevates Phosphorylated TrkB Protein Levels in Taste Cells, Increases Taste Bud Size, and Promotes Gustatory Innervation*

PubMed Central

Nosrat, Irina V.; Margolskee, Robert F.; Nosrat, Christopher A.

2012-01-01

Brain-derived neurotrophic factor (BDNF) is the most potent neurotrophic factor in the peripheral taste system during embryonic development. It is also expressed in adult taste buds. There is a lack of understanding of the role of BDNF in the adult taste system. To address this, we generated novel transgenic mice in which transgene expression was driven by an α-gustducin promoter coupling BDNF expression to the postnatal expression of gustducin in taste cells. Immunohistochemistry revealed significantly stronger BDNF labeling in taste cells of high BDNF-expressing mouse lines compared with controls. We show that taste buds in these mice are significantly larger and have a larger number of taste cells compared with controls. To examine whether innervation was affected in Gust-BDNF mice, we used antibodies to neural cell adhesion molecule (NCAM) and ATP receptor P2X3. The total density of general innervation and specifically the gustatory innervation was markedly increased in high BDNF-expressing mice compared with controls. TrkB and NCAM gene expression in laser capture microdissected taste epithelia were significantly up-regulated in these mice. Up-regulation of TrkB transcripts in taste buds and elevated taste cell-specific TrkB phosphorylation in response to increased BDNF levels indicate that BDNF controls the expression and activation of its high affinity receptor in taste cells. This demonstrates a direct taste cell function for BDNF. BDNF also orchestrates and maintains taste bud innervation. We propose that the Gust-BDNF transgenic mouse models can be employed to further dissect the specific roles of BDNF in the adult taste system. PMID:22442142

Localization of tritiated vitamin A in lymph nodes of the mouse: an autoradiographic study of vitamin A-storing cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirosawa, K.; Yamada, E.

1981-07-01

Localization of tritiated vitamin A in lymph nodes of the mouse was investigated by the use of light- and electron-microscopic autoradiography. Young male mice were fed a diet containing 3H-vitamin A acetate for a week. Lymph nodes were removed and prepared for autoradiography. Lipid droplets in fibroblast-like cells showed high concentrations of radioactivity. These cells were distributed around lymphatic sinuses and blood vessels. The cells can, therefore, be classified as ''vitamin A-storing cells'' according to criteria proposed earlier by Yamada and Hirosawa (1976). Control animals from the same litter were maintained on ordinary laboratory food for the same period andmore » examined by electron microscopy. Lipid-droplet-containing cells were found in the same areas as in the experimental animals but in fewer numbers. This suggests that the increased number of vitamin A-containing lipid droplets is due to hypervitaminosis A in the experimental animals. The presence of some cells containing these droplets in the control animals would imply that even under normal feeding conditions the animals ingested excess amounts of vitamin A, which was retained in lipid droplets. The stored vitamin A probably participates in metabolic processes such as the formation of glycoproteins in ground substance.« less

Treatment of d-galactose induced mouse aging with Lycium barbarum polysaccharides and its mechanism study.

PubMed

Tang, Tao; He, Bixiu

2013-01-01

We evaluated the effects of Lycium barbarum polysaccharides LBP) on D-galactose aging model mouse, and explored its possible mechanism. Kunming mice were randomly divided into the control group, the model group, the high-dose LBP group, and the low-dose LBP group. Except the control group, D-galactose was used for modelling. The drug was administrated when modelling. Mouse behavioural, learning and memory changes were observed, and the contents of lipid peroxidation (LPO), lipofuscin (LF) and monoamine oxidase B (MAO-B) in mouse brain tissue and the weight of immune organs were measured after 6 weeks. Compared with the control group, mouse weight gain in the model group reduced significantly. Compared with model group, after mice drank LBP, the times of electric shock was less than aging mice (in which, the high-dose LBP group, P<0.05), and electric shock incubation period was longer (P<0.01). On Day 45 after modelling and drug administration, the contents of LPO, LF and MAO-B in mouse brain tissue in the model group increased significantly, while those in the drug administration groups decreased significantly. The thymus index in the aging model group decreased significantly; the thymus index and the spleen index in the high-dose LBP group and the low-dose LBP group rebounded significantly (P<0.01). We concluded that LBP has an anti-aging effect on D-galactose induced aging model mouse, and its mechanism may be related with the alleviation of glucose metabolism disorder and the resistance of the generation of lipid peroxide and other substances, which damage cell membrane lipid.

Retinal ganglion cell responses to voltage and current stimulation in wild-type and rd1 mouse retinas

NASA Astrophysics Data System (ADS)

Goo, Yong Sook; Ye, Jang Hee; Lee, Seokyoung; Nam, Yoonkey; Ryu, Sang Baek; Kim, Kyung Hwan

2011-06-01

Retinal prostheses are being developed to restore vision for those with retinal diseases such as retinitis pigmentosa or age-related macular degeneration. Since neural prostheses depend upon electrical stimulation to control neural activity, optimal stimulation parameters for successful encoding of visual information are one of the most important requirements to enable visual perception. In this paper, we focused on retinal ganglion cell (RGC) responses to different stimulation parameters and compared threshold charge densities in wild-type and rd1 mice. For this purpose, we used in vitro retinal preparations of wild-type and rd1 mice. When the neural network was stimulated with voltage- and current-controlled pulses, RGCs from both wild-type and rd1 mice responded; however the temporal pattern of RGC response is very different. In wild-type RGCs, a single peak within 100 ms appears, while multiple peaks (approximately four peaks) with ~10 Hz rhythm within 400 ms appear in RGCs in the degenerated retina of rd1 mice. We find that an anodic phase-first biphasic voltage-controlled pulse is more efficient for stimulation than a biphasic current-controlled pulse based on lower threshold charge density. The threshold charge densities for activation of RGCs both with voltage- and current-controlled pulses are overall more elevated for the rd1 mouse than the wild-type mouse. Here, we propose the stimulus range for wild-type and rd1 retinas when the optimal modulation of a RGC response is possible.

N-Acetylcysteine Increases Corneal Endothelial Cell Survival in a Mouse Model of Fuchs Endothelial Corneal Dystrophy

PubMed Central

Kim, Eun Chul; Meng, Huan; Jun, Albert S.

2014-01-01

The present study evaluated survival effects of N-acetylcysteine (NAC) on cultured corneal endothelial cells exposed to oxidative and endoplasmic reticulum (ER) stress and in a mouse model of early-onset Fuchs endothelial corneal dystrophy (FECD). Cultured bovine corneal endothelial cell viability against oxidative and ER stress was determined by CellTiter-Glo® luminescent reagent. Two-month-old homozygous knock-in Col8a2L450W/L450W mutant (L450W) and C57/Bl6 wild-type (WT) animals were divided into two groups of 15 mice. Group I received 7 mg/mL NAC in drinking water and Group II received control water for 7 months. Endothelial cell density and morphology were evaluated with confocal microscopy. Antioxidant gene (iNos) and ER stress/unfolded protein response gene (Grp78 and Chop) mRNA levels and protein expression were measured in corneal endothelium by real time PCR and Western blotting. Cell viability of H2O2 and thapsigargin exposed cells pre-treated with NAC was significantly increased compared to untreated controls (pitalic>0.01). Corneal endothelial cell density (CD) was higher (p=0.001) and percent polymegathism was lower (p=0.04) in NAC treated L450W mice than in untreated L450W mice. NAC treated L450W endothelium showed significant upregulation of iNos, whereas Grp78 and Chop were downregulated compared to untreated L450W endothelium by real time PCR and Western blotting. NAC increases survival in cultured corneal endothelial cells exposed against ER and oxidative stress. Systemic NAC ingestion increases corneal endothelial cell survival which is associated with increased antioxidant and decreased ER stress markers in a mouse model of early-onset FECD. Our study presents in vivo evidence of a novel potential medical treatment for FECD. PMID:24952277

N-Acetylcysteine increases corneal endothelial cell survival in a mouse model of Fuchs endothelial corneal dystrophy.

PubMed

Kim, Eun Chul; Meng, Huan; Jun, Albert S

2014-10-01

The present study evaluated survival effects of N-acetylcysteine (NAC) on cultured corneal endothelial cells exposed to oxidative and endoplasmic reticulum (ER) stress and in a mouse model of early-onset Fuchs endothelial corneal dystrophy (FECD). Cultured bovine corneal endothelial cell viability against oxidative and ER stress was determined by CellTiter-Glo(®) luminescent reagent. Two-month-old homozygous knock-in Col8a2(L450W/L450W) mutant (L450W) and C57/Bl6 wild-type (WT) animals were divided into two groups of 15 mice. Group I received 7 mg/mL NAC in drinking water and Group II received control water for 7 months. Endothelial cell density and morphology were evaluated with confocal microscopy. Antioxidant gene (iNos) and ER stress/unfolded protein response gene (Grp78 and Chop) mRNA levels and protein expression were measured in corneal endothelium by real time PCR and Western blotting. Cell viability of H2O2 and thapsigargin exposed cells pre-treated with NAC was significantly increased compared to untreated controls (p < 0.01). Corneal endothelial cell density (CD) was higher (p = 0.001) and percent polymegathism was lower (p = 0.04) in NAC treated L450W mice than in untreated L450W mice. NAC treated L450W endothelium showed significant upregulation of iNos, whereas Grp78 and Chop were downregulated compared to untreated L450W endothelium by real time PCR and Western blotting. NAC increases survival in cultured corneal endothelial cells exposed against ER and oxidative stress. Systemic NAC ingestion increases corneal endothelial cell survival which is associated with increased antioxidant and decreased ER stress markers in a mouse model of early-onset FECD. Our study presents in vivo evidence of a novel potential medical treatment for FECD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Polyamine FTX-3.3 and polyamine amide sFTX-3.3 inhibit presynaptic calcium currents and acetylcholine release at mouse motor nerve terminals.

PubMed

Fatehi, M; Rowan, E G; Harvey, A L; Moya, E; Blagbrough, I S

1997-02-01

FTX-3.3 is the proposed structure of a calcium-channel blocking toxin that has been isolated from the funnel web spider (Agelenopsis aperta). The effects of FTX-3.3 and one of its analogues, sFTX-3.3, on acetylcholine release, on presynaptic currents at mouse motor nerve terminals and on whole-cell sodium currents in SK.N.SH cells (a human neuroblastoma cell line) have been studied. FTX-3.3 (10-30 microM) and sFTX-3.3 (100-300 microM) reversibly reduced release of acetylcholine by approximately 70-90% and 40-60%, respectively. FTX-3.3 (10 microM) blocked the fast component of presynaptic calcium currents by approximately 60%. sFTX-3.3 (100 microM) reduced the duration of the slow component of presynaptic calcium currents by about 50% of the control and also reduced presynaptic sodium current by approximately 20% of the control. sFTX-3.3 (100 microM) reduced whole-cell sodium current recorded from SK.N.SH cells by approximately 15%, whereas FTX-3.3, even at 200 microM, did not affect this current. Since the only difference in chemical structures of these toxins is that sFTX-3.3 has an amide function which is absent in FTX-3.3, the amide function may be responsible for the reduced potency and selectivity of sFTX-3.3. This study also provides further support for the existence of P-type calcium channels at mouse motor nerve terminals.

Surface immunoglobulin on cultured foetal mouse thymocytes

PubMed Central

Haustein, D.; Mandel, T. E.

1979-01-01

Organ cultures of 14–15 day foetal mouse thymus were used as a source of non-neoplastic differentiating T cells, free of contaminating B cells. Viable cells obtained from such cultured thymuses were radio-iodinated and immunoglobulins (Ig) were isolated by co-precipitation from the 125I-labelled cell-surface proteins released during 1 h of incubation at 37°. The precipitates, both reduced and unreduced, were then analysed by polyacrylamide gel electrophoresis. The unreduced material migrated in a 5% gel as a single peak with a mobility slightly faster than that of mouse IgG. After reduction, however, two peaks were obtained (in a 10% gel), one corresponding in migration to mouse light chain and the other which moved slightly faster than mouse μ chain. This pattern was identical with that previously seen for both surface Ig of normal mouse thymocytes and neoplastic T lymphoma cells. Uncultured, 15 day foetal thymocytes did not produce any detectable co-precipitated cell surface material. Ig detected in these experiments was therefore produced during in vitro culture by non-neoplastic T cells in a system free of contaminating B cells and mouse serum proteins. PMID:315364

Ly49H signaling through DAP10 is essential for optimal natural killer cell responses to mouse cytomegalovirus infection

PubMed Central

Orr, Mark T.; Sun, Joseph C.; Hesslein, David G.T.; Arase, Hisashi; Phillips, Joseph H.; Takai, Toshiyuki

2009-01-01

The activating natural killer (NK) cell receptor Ly49H recognizes the mouse cytomegalovirus (MCMV) m157 glycoprotein expressed on the surface of infected cells and is required for protection against MCMV. Although Ly49H has previously been shown to signal via DAP12, we now show that Ly49H must also associate with and signal via DAP10 for optimal function. In the absence of DAP12, DAP10 enables Ly49H-mediated killing of m157-bearing target cells, proliferation in response to MCMV infection, and partial protection against MCMV. DAP10-deficient Ly49H+ NK cells, expressing only Ly49H–DAP12 receptor complexes, are partially impaired in their ability to proliferate during MCMV infection, display diminished ERK1/2 activation, produce less IFN-γ upon Ly49H engagement, and demonstrate reduced control of MCMV infection. Deletion of both DAP10 and DAP12 completely abrogates Ly49H surface expression and control of MCMV infection. Thus, optimal NK cell–mediated immunity to MCMV depends on Ly49H signaling through both DAP10 and DAP12. PMID:19332875

Effect of diphenyl ether herbicides and oxadiazon on porphyrin biosynthesis in mouse liver, rat primary hepatocyte culture and HepG2 cells.

PubMed

Krijt, J; van Holsteijn, I; Hassing, I; Vokurka, M; Blaauboer, B J

1993-01-01

The effects of the herbicides fomesafen, oxyfluorfen, oxadiazon and fluazifop-butyl on porphyrin accumulation in mouse liver, rat primary hepatocyte culture and HepG2 cells were investigated. Ten days of herbicide feeding (0.25% in the diet) increased the liver porphyrins in male C57B1/6J mice from 1.4 +/- 0.6 to 4.8 +/- 2.1 (fomesafen) 16.9 +2- 2.9 (oxyfluorfen) and 25.9 +/- 3.1 (oxadiazon) nmol/g wet weight, respectively. Fluazifop-butyl had no effect on liver porphyrin metabolism. Fomesafen, oxyfluorfen and oxadiazon increased the cellular porphyrin content of rat hepatocytes after 24 h of incubation (control, 3.2 pmol/mg protein, fomesafen, oxyfluorfen and oxadiazon at 0.125 mM concentration 51.5, 54.3 and 44.0 pmol/mg protein, respectively). The porphyrin content of HepG2 cells increased from 1.6 to 18.2, 10.6 and 9.2 pmol/mg protein after 24 h incubation with the three herbicides. Fluazifop-butyl increased hepatic cytochrome P450 levels and ethoxy- and pentoxyresorufin O-dealkylase (EROD and PROD) activity, oxyfluorfen increased PROD activity. Peroxisomal palmitoyl CoA oxidation increased after fomesafen and fluazifop treatment to about 500% of control values both in mouse liver and rat hepatocytes. Both rat hepatocytes and HepG2 cells can be used as a test system for the porphyrogenic potential of photobleaching herbicides.

Lutein facilitates physiological revascularization in a mouse model of retinopathy of prematurity.

PubMed

Fu, Zhongjie; Meng, Steven S; Burnim, Samuel B; Smith, Lois Eh; Lo, Amy Cy

2017-07-01

Retinopathy of prematurity is one of the leading causes of childhood blindness worldwide, with vessel growth cessation and vessel loss in phase I followed by neovascularization in phase II. Ischaemia contributes to its pathogenesis, and lutein protects against ischaemia-induced retinal damages. We aimed to investigate the effects of lutein on a murine model of oxygen-induced retinopathy. Mouse pups were exposed to 75% oxygen for 5 days and returned to room air for another 5 days. Vascular obliteration, neovascularization and blood vessel leakage were examined. Immunohistochemistry for glial cells and microglia were performed. Compared with vehicle controls, mouse pups receiving lutein treatment displayed smaller central vaso-obliterated area and reduced blood vessel leakage. No significant difference in neovascular area was found between lutein and vehicle controls. Lutein promoted endothelial tip cell formation and maintained the astrocytic template in the avascular area in oxygen-induced retinopathy. No significant changes in Müller cell gliosis and microglial activation in the central avascular area were found in lutein-treated pups. Our observations indicated that lutein significantly promoted normal retinal vascular regrowth in the central avascular area, possibly through promoting endothelial tip cell formation and preserving astrocytic template. Our results indicated that lutein might be considered as a supplement for the treatment of proliferative retinopathy of prematurity because of its role in facilitating the revascularization of normal vasculature. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

The retrograde delivery of adenovirus vector carrying the gene for brain-derived neurotrophic factor protects neurons and oligodendrocytes from apoptosis in the chronically compressed spinal cord of twy/twy mice.

PubMed

Uchida, Kenzo; Nakajima, Hideaki; Hirai, Takayuki; Yayama, Takafumi; Chen, Kebing; Guerrero, Alexander Rodriguez; Johnson, William Eustace; Baba, Hisatoshi

2012-12-15

The twy/twy mouse undergoes spontaneous chronic mechanical compression of the spinal cord; this in vivo model system was used to examine the effects of retrograde adenovirus (adenoviral vector [AdV])-mediated brain-derived neurotrophic factor (BDNF) gene delivery to spinal neural cells. To investigate the targeting and potential neuroprotective effect of retrograde AdV-mediated BDNF gene transfection in the chronically compressed spinal cord in terms of prevention of apoptosis of neurons and oligodendrocytes. Several studies have investigated the neuroprotective effects of neurotrophins, including BDNF, in spinal cord injury. However, no report has described the effects of retrograde neurotrophic factor gene delivery in compressed spinal cords, including gene targeting and the potential to prevent neural cell apoptosis. AdV-BDNF or AdV-LacZ (as a control gene) was injected into the bilateral sternomastoid muscles of 18-week old twy/twy mice for retrograde gene delivery via the spinal accessory motor neurons. Heterozygous Institute of Cancer Research mice (+/twy), which do not undergo spontaneous spinal compression, were used as a control for the effects of such compression on gene delivery. The localization and cell specificity of β-galactosidase expression (produced by LacZ gene transfection) and BDNF expression in the spinal cord were examined by coimmunofluorescence staining for neural cell markers (NeuN, neurons; reactive immunology protein, oligodendrocytes; glial fibrillary acidic protein, astrocytes; OX-42, microglia) 4 weeks after gene injection. The possible neuroprotection afforded by retrograde AdV-BDNF gene delivery versus AdV-LacZ-transfected control mice was assessed by scoring the prevalence of apoptotic cells (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells) and immunoreactivity to active caspases -3, -8, and -9, p75, neurofilament 200 kD (NF), and for the oligodendroglial progenitor marker, NG2. RESULTS.: Four weeks after injection, the retrograde delivery of the LacZ marker gene was identified in cervical spinal neurons and some glial cells, including oligodendrocytes in the white matter of the spinal cord, in both the twy/twy mouse and the heterozygous Institute of Cancer Research mouse (+/twy). In the compressed spinal cord of twy/twy mouse, AdV-BDNF gene transfection resulted in a significant decrease in the number of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells present in the spinal cord and a downregulation in the caspase apoptotic pathway compared with AdV-LacZ (control) gene transfection. There was a marked and significant increase in the areas of the spinal cord of AdV-BDNF-injected mice that were NF- and NG2-immunopositive compared with AdV-LacZ-injected mice, indicating the increased presence of neurons and oligodendrocytes in response to BDNF transfection. Our results demonstrate that targeted retrograde BDNF gene delivery suppresses apoptosis in neurons and oligodendrocytes in the chronically compressed spinal cord of twy/twy mouse. Further work is required to establish whether this method of gene delivery may provide neuroprotective effects in other situations of compressive spinal cord injury.

The differential effects of 2% oxygen preconditioning on the subsequent differentiation of mouse and human pluripotent stem cells.

PubMed

Fynes, Kate; Tostoes, Rui; Ruban, Ludmila; Weil, Ben; Mason, Christopher; Veraitch, Farlan S

2014-08-15

A major challenge facing the development of effective cell therapies is the efficient differentiation of pluripotent stem cells (PSCs) into pure populations. Lowering oxygen tension to physiological levels can affect both the expansion and differentiation stages. However, to date, there are no studies investigating the knock-on effect of culturing PSCs under low oxygen conditions on subsequent lineage commitment at ambient oxygen levels. PSCs were passaged three times at 2% O2 before allowing cells to spontaneously differentiate as embryoid bodies (EBs) in high oxygen (20% O2) conditions. Maintenance of mouse PSCs in low oxygen was associated with a significant increase in the expression of early differentiation markers FGF5 and Eomes, while conversely we observed decreased expression of these genes in human PSCs. Low oxygen preconditioning primed mouse PSCs for their subsequent differentiation into mesodermal and endodermal lineages, as confirmed by increased gene expression of Eomes, Goosecoid, Brachyury, AFP, Sox17, FoxA2, and protein expression of Brachyury, Eomes, Sox17, FoxA2, relative to high oxygen cultures. The effects extended to the subsequent formation of more mature mesodermal lineages. We observed significant upregulation of cardiomyocyte marker Nkx2.5, and critically a decrease in the number of contaminant pluripotent cells after 12 days using a directed cardiomyocyte protocol. However, the impact of low oxygen preconditioning was to prime human cells for ectodermal lineage commitment during subsequent EB differentiation, with significant upregulation of Nestin and β3-tubulin. Our research demonstrates the importance of oxygen tension control during cell maintenance on the subsequent differentiation of both mouse and human PSCs, and highlights the differential effects.

Xenogeneic spermatogenesis following transplantation of hamster germ cells to mouse testes.

PubMed

Ogawa, T; Dobrinski, I; Avarbock, M R; Brinster, R L

1999-02-01

It was recently demonstrated that rat spermatogenesis can occur in the seminiferous tubules of an immunodeficient recipient mouse after transplantation of testis cells from a donor rat. In the present study, hamster donor testis cells were transplanted to mice to determine whether xenogeneic spermatogenesis would result. The hamster diverged at least 16 million years ago from the mouse and produces spermatozoa that are larger than, and have a shape distinctly different from, those of the mouse. In four separate experiments with a total of 13 recipient mice, hamster spermatogenesis was identified in the testes of each mouse. Approximately 6% of the tubules examined demonstrated xenogeneic spermatogenesis. In addition, cryopreserved hamster testis cells generated spermatogenesis in recipients. However, abnormalities were noted in hamster spermatids and acrosomes in seminiferous tubules of recipient mice. Hamster spermatozoa were also found in the epididymis of recipient animals, but these spermatozoa generally lacked acrosomes, and heads and tails were separated. Thus, defects in spermiogenesis occur in hamster spermatogenesis in the mouse, which may reflect a limited ability of endogenous mouse Sertoli cells to support fully the larger and evolutionarily distant hamster germ cell. The generation of spermatogenesis from frozen hamster cells now adds this species to the mouse and rat, in which spermatogonial stem cells also can be cryopreserved. This finding has immediate application to valuable animals of many species, because the cells could be stored until suitable recipients are identified or culture techniques devised to expand the stem cell population.

In Vivo Imaging of mdrla Gene Expression

DTIC Science & Technology

2005-06-01

svImJ mouse strain, compatible with the ES cells used in our Transgenic Mouse Facility. b. Engineer PGK-neo and Renilla luciferase cassettes...inserted between the two loxP sites, upstream of the Neo cassette. A cloning strategy was then devised to fuse Renilla luciferase in-frame with the...sites: B, BamHI; E, EcoRI; S, ScaI. PGK-neo: neo under the control of the PGK promoter. Luc: Renilla luciferase fused in- frame with the translated

The RNA-binding protein Musashi-1 is produced in the developing and adult mouse eye.

PubMed

Raji, B; Dansault, A; Leemput, J; de la Houssaye, G; Vieira, V; Kobetz, A; Arbogast, L; Masson, C; Menasche, M; Abitbol, M

2007-08-10

Musashi-1 (Msi1) is an RNA-binding protein produced in various types of stem cells including neural stem/progenitor cells and astroglial progenitor cells in the vertebrate central nervous system. Other RNA-binding proteins such as Pumilio-1, Pumilio-2, Staufen-1, and Staufen-2 have been characterized as potential markers of several types of stem or progenitor cells. We investigated the involvement of Msi1 in mouse eye development and adult mouse eye functions by analyzing the profile of Msi1 production in all ocular structures during development and adulthood. We studied Msi1 production by in situ hybridization and immunohistochemistry of ocular tissue sections and by semi-quantitative RT-PCR and western blot analysis from the embryonic stage of 12.5 days post coitum (E12.5 dpc) when the first retinal ganglion cells (RGCs) begin to appear to the adult stage when all retinal cell types are present. Msi1 mRNA was present at all studied stages of eye development. Msi1 protein was detected in the primitive neuroblastic layer (NbL), the ganglion cell layer (GCL), and in all major differentiated neurons of postnatal developing and adult retinae. During postnatal developing stages, faint diffuse Msi1 protein staining is converted to a more specific distribution once mouse retina is fully differentiated. The most striking result of our study concerns the large amounts of Msi1 protein and mRNA in several unexpected sites of adult mouse eyes including the corneal epithelium and endothelium, stromal keratocytes, progenitor cells of the limbus, equatorial lens stem cells, differentiated lens epithelial cells, and differentiating lens fibers. Msi1 was also found in the pigmented and nonpigmented cells of the ciliary processes, the melanocytes of the ciliary body, the retinal pigment epithelium, differentiated retinal neurons, and most probably in the retinal glial cells such as Müller glial cells, astrocytes, and the oligodendocytes surrounding the axons of the optic nerve. Msi1 expression was detected in the outer plexiform layer, the inner plexiform layer, and the nerve fiber layer of fully differentiated adult retina. We provide here the first demonstration that the RNA-binding protein, Msi1, is produced in mouse eyes from embryonic stages until adulthood. The relationship between the presence of Msi1 in developing ocular compartments and the possible stem/progenitor cell characteristics of these compartments remains unclear. Finally, the expression of Msi1 in several different cell types in the adult eye is extremely intriguing and should lead to further attempts to unravel the role of Msi1 in cellular and subcellular RNA metabolism and in the control of translational processes in adult eye cells particularly in adult neuronal dendrites, axons, and synapses.

Saccharomyces cerevisiae-derived virus-like particle parvovirus B19 vaccine elicits binding and neutralizing antibodies in a mouse model for sickle cell disease.

PubMed

Penkert, Rhiannon R; Young, Neal S; Surman, Sherri L; Sealy, Robert E; Rosch, Jason; Dormitzer, Philip R; Settembre, Ethan C; Chandramouli, Sumana; Wong, Susan; Hankins, Jane S; Hurwitz, Julia L

2017-06-22

Parvovirus B19 infections are typically mild in healthy individuals, but can be life threatening in individuals with sickle cell disease (SCD). A Saccharomyces cerevisiae-derived B19 VLP vaccine, now in pre-clinical development, is immunogenic in wild type mice when administered with the adjuvant MF59. Because SCD alters the immune response, we evaluated the efficacy of this vaccine in a mouse model for SCD. Vaccinated mice with SCD demonstrated similar binding and neutralizing antibody responses to those of heterozygous littermate controls following a prime-boost-boost regimen. Due to the lack of a mouse parvovirus B19 challenge model, we employed a natural mouse pathogen, Sendai virus, to evaluate SCD respiratory tract responses to infection. Normal mucosal and systemic antibody responses were observed in these mice. Results demonstrate that mice with SCD can respond to a VLP vaccine and to a respiratory virus challenge, encouraging rapid development of the B19 vaccine for patients with SCD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro.

PubMed

Cong, Shan; Cao, Guifang; Liu, Dongjun

2014-12-01

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1-5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.

Local convection-enhanced delivery of an anti-CD40 agonistic monoclonal antibody induces antitumor effects in mouse glioma models.

PubMed

Shoji, Takuhiro; Saito, Ryuta; Chonan, Masashi; Shibahara, Ichiyo; Sato, Aya; Kanamori, Masayuki; Sonoda, Yukihiko; Kondo, Toru; Ishii, Naoto; Tominaga, Teiji

2016-08-01

Glioblastoma is one of the most malignant brain tumors in adults and has a dismal prognosis. In a previous report, we reported that CD40, a TNF-R-related cell surface receptor, and its ligand CD40L were associated with glioma outcomes. Here we attempted to activate CD40 signaling in the tumor and determine if it exerted therapeutic efficacy. CD40 expression was examined in 3 mouse glioma cell lines (GL261, NSCL61, and bRiTs-G3) and 5 human glioma cell lines (U87, U251, U373, T98, and A172). NSCL61 and bRiTs-G3, as glioma stem cells, also expressed the glioma stem cell markers MELK and CD44. In vitro, we demonstrated direct antitumor effects of an anti-CD40 agonistic monoclonal antibody (FGK45) against the cell lines. The efficacy of FGK45 was examined by local convection-enhanced delivery of the monoclonal antibody against each glioma model. CD40 was expressed in all mouse and human cell lines tested and was found at the cell membrane of each of the 3 mouse cell lines. FGK45 administration induced significant, direct antitumor effects in vitro. The local delivery of FGK45 significantly prolonged survival compared with controls in the NSCL61 and bRiTs-G3 models, but the effect was not significant in the GL261 model. Increases in apoptosis and CD4(+) and CD8(+) T cell infiltration were observed in the bRiTs-G3 model after FGK45 treatment. Local delivery of FGK45 significantly prolonged survival in glioma stem cell models. Thus, local delivery of this monoclonal antibody is promising for immunotherapy against gliomas. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

PD-1 regulates T cell proliferation in a tissue and subset specific manner during normal mouse pregnancy

PubMed Central

Shepard, Michelle T.; Bonney, Elizabeth A.

2014-01-01

The regulation of T cell homeostasis during pregnancy has important implications for maternal tolerance and immunity. Evidence suggests that Programmed Death-1 (PD-1) participates in regulation of T cell homeostasis and peripheral tolerance. To examine the contribution of PD-1 signaling on T cell homeostasis during normal mouse pregnancy, we examined T cell number or proportion, PD-1 expression, proliferation, and apoptosis by flow cytometry, BrdU incorporation, and TUNEL assay in pregnant mice given anti-PD-1 blocking antibody or control on days 10, 12, and 14 of gestation. We observed tissue, treatment, and T cell-specific differences in PD-1 expression. Both pregnancy and PD-1 blockade increased T cell proliferation in the spleen while this effect was limited to CD4 T cells in the uterine- draining nodes. In the uterus, PD-1 blockade markedly altered the composition of the T cell pool. These studies support the idea that pregnancy is a state of dynamic T cell homeostasis and suggest that this state is partially supported by PD-1 signaling. PMID:23782245

Analysis of Hippo and TGFβ signaling in polarizing epithelial cells and mouse embryos.

PubMed

Narimatsu, Masahiro; Labibi, Batool; Wrana, Jeffrey L; Attisano, Liliana

2016-01-01

The Hippo signaling pathway is involved in numerous biological events ranging from early development to organogenesis and when disrupted, impacts various human diseases including cancer. The Hippo pathway also interacts with and controls the activity of other signaling pathways such as the TGFβ/Smad pathway, in which Hippo pathway activity influences the subcellular localization of Smad transcription factors. Here, we describe techniques for examining crosstalk between Hippo and TGFβ signaling in polarizing mammary epithelial cells. In addition, we provide detailed methods for analyzing the subcellular localization of the Hippo pathway effectors, Taz and Yap using both in vitro cultured epithelial cells and in vivo in pregastrulation mouse embryos. Copyright © 2016 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

An Advanced Preclinical Mouse Model for Acute Myeloid Leukemia Using Patients' Cells of Various Genetic Subgroups and In Vivo Bioluminescence Imaging

PubMed Central

Vick, Binje; Rothenberg, Maja; Sandhöfer, Nadine; Carlet, Michela; Finkenzeller, Cornelia; Krupka, Christina; Grunert, Michaela; Trumpp, Andreas; Corbacioglu, Selim; Ebinger, Martin; André, Maya C.; Hiddemann, Wolfgang; Schneider, Stephanie; Subklewe, Marion; Metzeler, Klaus H.; Spiekermann, Karsten; Jeremias, Irmela

2015-01-01

Acute myeloid leukemia (AML) is a clinically and molecularly heterogeneous disease with poor outcome. Adequate model systems are required for preclinical studies to improve understanding of AML biology and to develop novel, rational treatment approaches. Xenografts in immunodeficient mice allow performing functional studies on patient-derived AML cells. We have established an improved model system that integrates serial retransplantation of patient-derived xenograft (PDX) cells in mice, genetic manipulation by lentiviral transduction, and essential quality controls by immunophenotyping and targeted resequencing of driver genes. 17/29 samples showed primary engraftment, 10/17 samples could be retransplanted and some of them allowed virtually indefinite serial transplantation. 5/6 samples were successfully transduced using lentiviruses. Neither serial transplantation nor genetic engineering markedly altered sample characteristics analyzed. Transgene expression was stable in PDX AML cells. Example given, recombinant luciferase enabled bioluminescence in vivo imaging and highly sensitive and reliable disease monitoring; imaging visualized minimal disease at 1 PDX cell in 10000 mouse bone marrow cells and facilitated quantifying leukemia initiating cells. We conclude that serial expansion, genetic engineering and imaging represent valuable tools to improve the individualized xenograft mouse model of AML. Prospectively, these advancements enable repetitive, clinically relevant studies on AML biology and preclinical treatment trials on genetically defined and heterogeneous subgroups. PMID:25793878

Critical role of zinc finger protein 521 in the control of growth, clonogenicity and tumorigenic potential of medulloblastoma cells

PubMed Central

Iaccino, Enrico; Scicchitano, Stefania; Lupia, Michela; Chiarella, Emanuela; Mega, Tiziana; Bernaudo, Francesca; Pelaggi, Daniela; Mesuraca, Maria; Pazzaglia, Simonetta; Semenkow, Samantha; Bar, Eli E.; Kool, Marcel; Pfister, Stefan; Bond, Heather M.; Eberhart, Charles G.; Steinkühler, Christian; Morrone, Giovanni

2013-01-01

The stem cell-associated transcription co-factor ZNF521 has been implicated in the control of hematopoietic, osteo-adipogenic and neural progenitor cells. ZNF521 is highly expressed in cerebellum and in particular in the neonatal external granule layer that contains candidate medulloblastoma cells-of-origin, and in the majority of human medulloblastomas. Here we have explored its involvement in the control of human and murine medulloblastoma cells. The effect of ZNF521 on growth and tumorigenic potential of human medulloblastoma cell lines as well as primary Ptc1−/+ mouse medulloblastoma cells was investigated in a variety of in vitro and in vivo assays, by modulating its expression using lentiviral vectors carrying the ZNF521 cDNA, or shRNAs that silence its expression. Enforced overexpression of ZNF521 in DAOY medulloblastoma cells significantly increased their proliferation, growth as spheroids and ability to generate clones in single-cell cultures and semisolid media, and enhanced their migratory ability in wound-healing assays. Importantly, ZNF521-expressing cells displayed a greatly enhanced tumorigenic potential in nude mice. All these activities required the ZNF521 N-terminal motif that recruits the nucleosome remodeling and histone deacetylase complex, which might therefore represent an appealing therapeutic target. Conversely, silencing of ZNF521 in human UW228 medulloblastoma cells that display high baseline expression decreased their proliferation, clonogenicity, sphere formation and wound-healing ability. Similarly, Zfp521 silencing in mouse Ptc1−/+ medulloblastoma cells drastically reduced their growth and tumorigenic potential. Our data strongly support the notion that ZNF521, through the recruitment of the NuRD complex, contributes to the clonogenic growth, migration and tumorigenicity of medulloblastoma cells. PMID:23907569

Critical role of zinc finger protein 521 in the control of growth, clonogenicity and tumorigenic potential of medulloblastoma cells.

PubMed

Spina, Raffaella; Filocamo, Gessica; Iaccino, Enrico; Scicchitano, Stefania; Lupia, Michela; Chiarella, Emanuela; Mega, Tiziana; Bernaudo, Francesca; Pelaggi, Daniela; Mesuraca, Maria; Pazzaglia, Simonetta; Semenkow, Samantha; Bar, Eli E; Kool, Marcel; Pfister, Stefan; Bond, Heather M; Eberhart, Charles G; Steinkühler, Christian; Morrone, Giovanni

2013-08-01

The stem cell-associated transcription co-factor ZNF521 has been implicated in the control of hematopoietic, osteo-adipogenic and neural progenitor cells. ZNF521 is highly expressed in cerebellum and in particular in the neonatal external granule layer that contains candidate medulloblastoma cells-of-origin, and in the majority of human medulloblastomas. Here we have explored its involvement in the control of human and murine medulloblastoma cells. The effect of ZNF521 on growth and tumorigenic potential of human medulloblastoma cell lines as well as primary Ptc1-/+ mouse medulloblastoma cells was investigated in a variety of in vitro and in vivo assays, by modulating its expression using lentiviral vectors carrying the ZNF521 cDNA, or shRNAs that silence its expression. Enforced overexpression of ZNF521 in DAOY medulloblastoma cells significantly increased their proliferation, growth as spheroids and ability to generate clones in single-cell cultures and semisolid media, and enhanced their migratory ability in wound-healing assays. Importantly, ZNF521-expressing cells displayed a greatly enhanced tumorigenic potential in nude mice. All these activities required the ZNF521 N-terminal motif that recruits the nucleosome remodeling and histone deacetylase complex, which might therefore represent an appealing therapeutic target. Conversely, silencing of ZNF521 in human UW228 medulloblastoma cells that display high baseline expression decreased their proliferation, clonogenicity, sphere formation and wound-healing ability. Similarly, Zfp521 silencing in mouse Ptc1-/+ medulloblastoma cells drastically reduced their growth and tumorigenic potential. Our data strongly support the notion that ZNF521, through the recruitment of the NuRD complex, contributes to the clonogenic growth, migration and tumorigenicity of medulloblastoma cells.

Incorrect strain information for mouse cell lines: sequential influence of misidentification on sublines.

PubMed

Uchio-Yamada, Kozue; Kasai, Fumio; Ozawa, Midori; Kohara, Arihiro

2017-03-01

Misidentification or cross-contamination of cell lines can cause serious issues. Human cell lines have been authenticated by short tandem repeat profiling; however, mouse cell lines have not been adequately assessed. In this study, mouse cell lines registered with the JCRB cell bank were examined by simple sequence length polymorphism (SSLP) analysis to identify their strains. Based on comparisons with 7 major inbred strains, our results revealed their strains in 80 of 90 cell lines. However, 12 of the 80 cell lines (15%) were found to differ from registered information. Of them, 4 cell lines originated from the same mouse, which had been generated through mating between two different inbred strains. The genotype of the mouse sample had not been examined after the backcross, leading to strain misidentification in those cell lines. Although 8 other cell lines had been established as sublines of a BALB/c cell line, their SSLP profiles are similar to a Swiss cell line. This affects differences in genotypes between inbred and outbred strains. Because the use of inbred samples and interbreeding between strains are not involved in human materials, our results suggest that the cause and influence of misidentification in mouse cell lines are different from those in human.

Human amniotic epithelial cell feeder layers maintain mouse embryonic stem cell pluripotency via epigenetic regulation of the c-Myc promoter.

PubMed

Liu, Te; Cheng, Weiwei; Liu, Tianjin; Guo, Lihe; Huang, Qin; Jiang, Lizhen; Du, Xiling; Xu, Fuhui; Liu, Zhixue; Lai, Dongmei

2010-02-01

Mouse embryonic stem cells (ESCs) are typically cultured on a feeder layer of mouse embryonic fibroblasts (MEFs), with leukemia inhibitory factor (LIF) added to maintain them in an undifferentiated state. We have previously shown that human amniotic epithelial cells (hAECs) can be used as feeder cells to maintain mouse ESC pluripotency, but the mechanism for this is unknown. In the present study, we found that CpG islands 5' of the c-Myc gene remain hypomethylated in mouse ESCs cultured on hAECs. In addition, levels of acetylation of histone H3 and trimethylation of histone H3K4 in the c-Myc gene promoter were higher in ES cells cultured on hAECs than those in ES cells cultured on MEFs. These data suggested that hAECs can alter mouse ESC gene expression via epigenetic modification of c-Myc, providing a possible mechanism for the hAEC-induced maintenance of ESCs in an undifferentiated state.

GATA3 controls the specification of prosensory domain and neuronal survival in the mouse cochlea

PubMed Central

Luo, Xiong-jian; Deng, Min; Xie, Xiaoling; Huang, Liang; Wang, Hui; Jiang, Lichun; Liang, Guoqing; Hu, Fang; Tieu, Roger; Chen, Rui; Gan, Lin

2013-01-01

HDR syndrome (also known as Barakat syndrome) is a developmental disorder characterized by hypoparathyroidism, sensorineural deafness and renal disease. Although genetic mapping and subsequent functional studies indicate that GATA3 haplo-insufficiency causes human HDR syndrome, the role of Gata3 in sensorineural deafness and auditory system development is largely unknown. In this study, we show that Gata3 is continuously expressed in the developing mouse inner ear. Conditional knockout of Gata3 in the developing inner ear disrupts the morphogenesis of mouse inner ear, resulting in a disorganized and shortened cochlear duct with significant fewer hair cells and supporting cells. Loss of Gata3 function leads to the failure in the specification of prosensory domain and subsequently, to increased cell death in the cochlear duct. Moreover, though the initial generation of cochleovestibular ganglion (CVG) cells is not affected in Gata3-null mice, spiral ganglion neurons (SGNs) are nearly depleted due to apoptosis. Our results demonstrate the essential role of Gata3 in specifying the prosensory domain in the cochlea and in regulating the survival of SGNs, thus identifying a molecular mechanism underlying human HDR syndrome. PMID:23666531

Melanocortin-1 receptor activation is neuroprotective in mouse models of neuroinflammatory disease.

PubMed

Mykicki, Nadine; Herrmann, Alexander M; Schwab, Nicholas; Deenen, René; Sparwasser, Tim; Limmer, Andreas; Wachsmuth, Lydia; Klotz, Luisa; Köhrer, Karl; Faber, Cornelius; Wiendl, Heinz; Luger, Thomas A; Meuth, Sven G; Loser, Karin

2016-10-26

In inflammation-associated progressive neuroinflammatory disorders, such as multiple sclerosis (MS), inflammatory infiltrates containing T helper 1 (T H 1) and T H 17 cells cause demyelination and neuronal degeneration. Regulatory T cells (T reg ) control the activation and infiltration of autoreactive T cells into the central nervous system (CNS). In MS and experimental autoimmune encephalomyelitis (EAE) in mice, T reg function is impaired. We show that a recently approved drug, Nle 4 -d-Phe 7 -α-melanocyte-stimulating hormone (NDP-MSH), induced functional T reg , resulting in amelioration of EAE progression in mice. NDP-MSH also prevented immune cell infiltration into the CNS by restoring the integrity of the blood-brain barrier. NDP-MSH exerted long-lasting neuroprotective effects in mice with EAE and prevented excitotoxic death and reestablished action potential firing in mouse and human neurons in vitro. Neuroprotection by NDP-MSH was mediated via signaling through the melanocortin-1 and orphan nuclear 4 receptors in mouse and human neurons. NDP-MSH may be of benefit in treating neuroinflammatory diseases such as relapsing-remitting MS and related disorders. Copyright © 2016, American Association for the Advancement of Science.

Expression Profile of DNA Damage Signaling Genes in Proton Exposed Mouse Brain

NASA Astrophysics Data System (ADS)

Ramesh, Govindarajan; Wu, Honglu

Exposure of living systems to radiation results in a wide assortment of lesions, the most signif-icant of is damage to genomic DNA which induce several cellular functions such as cell cycle arrest, repair, apoptosis etc. The radiation induced DNA damage investigation is one of the im-portant area in biology, but still the information available regarding the effects of proton is very limited. In this report, we investigated the differential gene expression pattern of DNA damage signaling genes particularly, damaged DNA binding, repair, cell cycle arrest, checkpoints and apoptosis using quantitative real-time RT-PCR array in proton exposed mouse brain tissues. The expression profiles showed significant changes in DNA damage related genes in 2Gy proton exposed mouse brain tissues as compared with control brain tissues. Furthermore, we also show that significantly increased levels of apoptotic related genes, caspase-3 and 8 activities in these cells, suggesting that in addition to differential expression of DNA damage genes, the alteration of apoptosis related genes may also contribute to the radiation induced DNA damage followed by programmed cell death. In summary, our findings suggest that proton exposed brain tissue undergo severe DNA damage which in turn destabilize the chromatin stability.

Eradication of acute promyelocytic leukemia-initiating cells through PML-RARA degradation.

PubMed

Nasr, Rihab; Guillemin, Marie-Claude; Ferhi, Omar; Soilihi, Hassan; Peres, Laurent; Berthier, Caroline; Rousselot, Philippe; Robledo-Sarmiento, Macarena; Lallemand-Breitenbach, Valérie; Gourmel, Bernard; Vitoux, Dominique; Pandolfi, Pier Paolo; Rochette-Egly, Cécile; Zhu, Jun; de Thé, Hugues

2008-12-01

Retinoic acid and arsenic trioxide target the protein stability and transcriptional repression activity of the fusion oncoprotein PML-RARA, resulting in regression of acute promyelocytic leukemia (APL). Phenotypically, retinoic acid induces differentiation of APL cells. Here we show that retinoic acid also triggers growth arrest of leukemia-initiating cells (LICs) ex vivo and their clearance in PML-RARA mouse APL in vivo. Retinoic acid treatment of mouse APLs expressing the fusion protein PLZF-RARA triggers full differentiation, but not LIC loss or disease remission, establishing that differentiation and LIC loss can be uncoupled. Although retinoic acid and arsenic synergize to clear LICs through cooperative PML-RARA degradation, this combination does not enhance differentiation. A cyclic AMP (cAMP)-dependent phosphorylation site in PML-RARA is crucial for retinoic acid-induced PML-RARA degradation and LIC clearance. Moreover, activation of cAMP signaling enhances LIC loss by retinoic acid, identifying cAMP as another potential APL therapy. Thus, whereas transcriptional activation of PML-RARA is likely to control differentiation, its catabolism triggers LIC eradication and long-term remission of mouse APL. Therapy-triggered degradation of oncoproteins could be a general strategy to eradicate cancer stem cells.

High Molecular Weight Isoforms of Growth Hormone In Cells of the Immune System

PubMed Central

Weigent, Douglas A.

2013-01-01

A substantial body of research exists to support the idea that cells of the immune system produce growth hormone (GH). However, the structure and mechanism of action of lymphocyte-derived GH continues to remain largely unknown. Here we present the results of Western analysis of whole cell extracts showing that different molecular weight isoforms of GH of approximately 100 kDa, 65 kDa, and 48 kDa can be detected in primary mouse cells of the immune system and in the mouse EL4 cell line. The identity of the 65 kDa and 48 kDa isoforms of GH were confirmed by mass spectrometry. The various isoforms were detected in both enriched T and B spleen cell populations. The large molecular weight isoform appears to reside primarily in the cytoplasm whereas the lower molecular weight 65 kDa and 48 kDa isoforms were detected primarily in the nucleus. These results also suggest that GH isoforms are induced by oxidative stress. In EL4 cells overexpressing GH, the expression of luciferase controlled by a promoter containing the antioxidant response element is increased almost three-fold above control. The data suggest that the induction of isoforms of the GH molecule in cells of the immune system may be an important mechanism of adaptation and/or protection of lymphoid cells under conditions of oxidative stress. PMID:21741628

Sildenafil Promotes eNOS Activation and Inhibits NADPH Oxidase in the Transgenic Sickle Cell Mouse Penis

PubMed Central

Musicki, Biljana; Bivalacqua, Trinity J.; Champion, Hunter C.; Burnett, Arthur L.

2014-01-01

Introduction Sickle cell disease (SCD)-associated vasculopathy in the penis is characterized by aberrant nitric oxide and phosphodiesterase (PDE) 5 signaling, and by increased oxidative stress. Preliminary clinical trials show that continuous treatment with PDE5 inhibitor sildenafil unassociated with sexual activity decreases priapic activity in patients with SCD. However, the mechanism of its vasculoprotective effect in the penis remains unclear. Aims We evaluated whether continuous administration of PDE5 inhibitor sildenafil promotes eNOS function at posttranslational levels and decreases superoxide-producing enzyme NADPH oxidase activity in the sickle cell mouse penis. Methods SCD transgenic mice were used as an animal model of SCD. WT mice served as controls. Mice received treatment with the PDE5 inhibitor sildenafil (100 mg/kg/day) or vehicle for 3 weeks. eNOS phosphorylation on Ser-1177 (positive regulatory site), eNOS interactions with heat-shock protein 90 (HSP90) (positive regulator), phosphorylated AKT (upstream mediator of eNOS phosphorylation on Ser-1177), an NADPH oxidase catalytic subunit gp91(phox), and a marker of oxidative stress (4-hydroxy-2-nonenal [HNE]) were measured by Western blot. Main Outcome Measures Effect of continuous sildenafil treatment on eNOS posttranslational activation, NADPH oxidase catalytic subunit, and oxidative stress in the penis of the sickle cell mouse. Results Continuous treatment with sildenafil reversed (P < 0.05) the abnormalities in protein expressions of P-eNOS (Ser-1177), eNOS/HSP90 interaction, P-AKT, protein expression of gp91(phox), and 4-HNE, in the sickle cell mouse penis. Sildenafil treatment of WT mice did not affect any of these parameters. Conclusion Our findings that sildenafil enhances eNOS activation and inhibits NADPH oxidase function in the sickle cell mouse penis offers a vasculoprotective molecular basis for the therapeutic effect of sildenafil in the penis in association with SCD. PMID:24251665

Sildenafil promotes eNOS activation and inhibits NADPH oxidase in the transgenic sickle cell mouse penis.

PubMed

Musicki, Biljana; Bivalacqua, Trinity J; Champion, Hunter C; Burnett, Arthur L

2014-02-01

Sickle cell disease (SCD)-associated vasculopathy in the penis is characterized by aberrant nitric oxide and phosphodiesterase (PDE) 5 signaling, and by increased oxidative stress. Preliminary clinical trials show that continuous treatment with PDE5 inhibitor sildenafil unassociated with sexual activity decreases priapic activity in patients with SCD. However, the mechanism of its vasculoprotective effect in the penis remains unclear. We evaluated whether continuous administration of PDE5 inhibitor sildenafil promotes eNOS function at posttranslational levels and decreases superoxide-producing enzyme NADPH oxidase activity in the sickle cell mouse penis. SCD transgenic mice were used as an animal model of SCD. WT mice served as controls. Mice received treatment with the PDE5 inhibitor sildenafil (100 mg/kg/day) or vehicle for 3 weeks. eNOS phosphorylation on Ser-1177 (positive regulatory site), eNOS interactions with heat-shock protein 90 (HSP90) (positive regulator), phosphorylated AKT (upstream mediator of eNOS phosphorylation on Ser-1177), an NADPH oxidase catalytic subunit gp91(phox), and a marker of oxidative stress (4-hydroxy-2-nonenal [HNE]) were measured by Western blot. Effect of continuous sildenafil treatment on eNOS posttranslational activation, NADPH oxidase catalytic subunit, and oxidative stress in the penis of the sickle cell mouse. Continuous treatment with sildenafil reversed (P < 0.05) the abnormalities in protein expressions of P-eNOS (Ser-1177), eNOS/HSP90 interaction, P-AKT, protein expression of gp91(phox), and 4-HNE, in the sickle cell mouse penis. Sildenafil treatment of WT mice did not affect any of these parameters. Our findings that sildenafil enhances eNOS activation and inhibits NADPH oxidase function in the sickle cell mouse penis offers a vasculoprotective molecular basis for the therapeutic effect of sildenafil in the penis in association with SCD. © 2013 International Society for Sexual Medicine.

Selective destruction of mouse islet beta cells by human T lymphocytes in a newly-established humanized type 1 diabetic model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Yong, E-mail: yongzhao@uic.edu; Guo, Chengshan; Hwang, David

2010-09-03

Research highlights: {yields} Establish a human immune-mediated type 1 diabetic model in NOD-scid IL2r{gamma}{sup null} mice. {yields} Using the irradiated diabetic NOD mouse spleen mononuclear cells as trigger. {yields} The islet {beta} cells were selectively destroyed by infiltrated human T cells. {yields} The model can facilitate translational research to find a cure for type 1 diabetes. -- Abstract: Type 1 diabetes (T1D) is caused by a T cell-mediated autoimmune response that leads to the loss of insulin-producing {beta} cells. The optimal preclinical testing of promising therapies would be aided by a humanized immune-mediated T1D model. We develop this model inmore » NOD-scid IL2r{gamma}{sup null} mice. The selective destruction of pancreatic islet {beta} cells was mediated by human T lymphocytes after an initial trigger was supplied by the injection of irradiated spleen mononuclear cells (SMC) from diabetic nonobese diabetic (NOD) mice. This resulted in severe insulitis, a marked loss of total {beta}-cell mass, and other related phenotypes of T1D. The migration of human T cells to pancreatic islets was controlled by the {beta} cell-produced highly conserved chemokine stromal cell-derived factor 1 (SDF-1) and its receptor C-X-C chemokine receptor (CXCR) 4, as demonstrated by in vivo blocking experiments using antibody to CXCR4. The specificity of humanized T cell-mediated immune responses against islet {beta} cells was generated by the local inflammatory microenvironment in pancreatic islets including human CD4{sup +} T cell infiltration and clonal expansion, and the mouse islet {beta}-cell-derived CD1d-mediated human iNKT activation. The selective destruction of mouse islet {beta} cells by a human T cell-mediated immune response in this humanized T1D model can mimic those observed in T1D patients. This model can provide a valuable tool for translational research into T1D.« less

Effect of human cell malignancy on activity of DNA polymerase iota.

PubMed

Kazakov, A A; Grishina, E E; Tarantul, V Z; Gening, L V

2010-07-01

An increased level of mutagenesis, partially caused by imbalanced activities of error prone DNA polymerases, is a key symptom of cell malignancy. To clarify the possible role of incorrect DNA polymerase iota (Pol iota) function in increased frequency of mutations in mammalian cells, the activity of this enzyme in extracts of cells of different mouse organs and human eye (melanoma) and eyelid (basal-cell skin carcinoma) tumor cells was studied. Both Mg2+, considered as the main activator of the enzyme reaction of in vivo DNA replication, and Mn2+, that activates homogeneous Pol iota preparations in experiments in vitro more efficiently compared to all other bivalent cations, were used as cofactors of the DNA polymerase reaction in these experiments. In the presence of Mg2+, the enzyme was active only in cell extracts of mouse testicles and brain, whereas in the presence of Mn2+ the activity of Pol iota was found in all studied normal mouse organs. It was found that in cell extracts of both types of malignant tumors (basal-cell carcinoma and melanoma) Pol iota activity was observed in the presence of either Mn2+ or Mg2+. Manganese ions activated Pol iota in both cases, though to a different extent. In the presence of Mn2+ the Pol iota activity in the basal-cell carcinoma exceeded 2.5-fold that in control cells (benign tumors from the same eyelid region). In extracts of melanoma cells in the presence of either cation, the level of the enzyme activity was approximately equal to that in extracts of cells of surrounding tumor-free tissues as well as in eyes removed after traumas. The distinctive feature of tissue malignancy (in basal-cell carcinoma and in melanoma) was the change in DNA synthesis revealed as Mn2+-activated continuation of DNA synthesis after incorrect incorporation of dG opposite dT in the template by Pol iota. Among cell extracts of different normal mouse organs, only those of testicles exhibited a similar feature. This similarity can be explained by cell division blocking that occurs in all normal cells except in testicles and in malignant cells.

NK cell heparanase controls tumor invasion and immune surveillance

PubMed Central

Putz, Eva M.; Mayfosh, Alyce J.; Barkauskas, Deborah S.; Nakamura, Kyohei; Town, Liam; Goodall, Katharine J.; Yee, Dean Y.; Poon, Ivan K.H.; Baschuk, Nikola; Souza-Fonseca-Guimaraes, Fernando; Hulett, Mark D.; Smyth, Mark J.

2017-01-01

NK cells are highly efficient at preventing cancer metastasis but are infrequently found in the core of primary tumors. Here, have we demonstrated that freshly isolated mouse and human NK cells express low levels of the endo-β-D-glucuronidase heparanase that increase upon NK cell activation. Heparanase deficiency did not affect development, differentiation, or tissue localization of NK cells under steady-state conditions. However, mice lacking heparanase specifically in NK cells (Hpsefl/fl NKp46-iCre mice) were highly tumor prone when challenged with the carcinogen methylcholanthrene (MCA). Hpsefl/fl NKp46-iCre mice were also more susceptible to tumor growth than were their littermate controls when challenged with the established mouse lymphoma cell line RMA-S-RAE-1β, which overexpresses the NK cell group 2D (NKG2D) ligand RAE-1β, or when inoculated with metastatic melanoma, prostate carcinoma, or mammary carcinoma cell lines. NK cell invasion of primary tumors and recruitment to the site of metastasis were strictly dependent on the presence of heparanase. Cytokine and immune checkpoint blockade immunotherapy for metastases was compromised when NK cells lacked heparanase. Our data suggest that heparanase plays a critical role in NK cell invasion into tumors and thereby tumor progression and metastases. This should be considered when systemically treating cancer patients with heparanase inhibitors, since the potential adverse effect on NK cell infiltration might limit the antitumor activity of the inhibitors. PMID:28581441

Discovery of cancer biomarkers through the use of mouse models.

PubMed

Kuick, Rork; Misek, David E; Monsma, David J; Webb, Craig P; Wang, Hong; Peterson, Kelli J; Pisano, Michael; Omenn, Gilbert S; Hanash, Samir M

2007-04-28

Although our understanding of the molecular pathogenesis of common types of cancer has improved considerably, the development of effective strategies for cancer diagnosis and treatment have lagged behind. Mouse models of cancer potentially represent an efficient means for uncovering diagnostic markers as genetic alterations associated with human tumors can be engineered in mice. In addition, defined stages of tumor development, breeding conditions, and blood sampling can all be controlled and standardized to limit heterogeneity. Alternatively human cancer cells can be injected into mice and tumor development monitored in xenotransplants. Mouse-based studies promise to elucidate a repertoire of protein changes that occur in blood and biological fluids during tumor development. This is illustrated in a study in which we have applied a three-dimensional intact protein analysis system (IPAS) to elucidate detectable protein changes in serum from immunodeficient mice with lung xenografts from orthotopically implanted human A549 lung adenocarcinoma cells. With sufficiently detailed protein sequence identifications, the observed protein changes can be attributed to either the host mouse or the human tumor cells. It is noteworthy that the majority of increases identified have corresponded to relatively abundant serum proteins, some of which have previously been reported as increased in the sera of cancer patients. Proteomic studies of mouse models of cancer allow assessment of the range of changes in plasma proteins that occur with tumor development and may lead to the identification of potential cancer markers applicable to humans.

A Co-Receptor Independent Transgenic Human TCR Mediates Anti-Tumor and Anti-Self Immunity in Mice

PubMed Central

Mehrotra, Shikhar; Al-Khami, Amir A.; Klarquist, Jared; Husain, Shahid; Naga, Osama; Eby, Jonathan M.; Murali, Anuradha K.; Lyons, Gretchen E.; Li, Mingli; Spivey, Natali D.; Norell, Håkan; Martins da Palma, Telma; Onicescu, Georgiana; Diaz-Montero, C. Marcela; Garrett-Mayer, Elizabeth; Cole, David J.; Le Poole, I. Caroline; Nishimura, Michael I.

2013-01-01

Recent advancements in T cell immunotherapy suggest that T cells engineered with high affinity T cell receptors (TCR) can offer better tumor regression. However, whether a high affinity TCR alone is sufficient to control tumor growth, or the T cell subset bearing the TCR is also important remains unclear. Using the human tyrosinase epitope reactive, CD8 independent, high affinity TCR isolated from MHC class-I restricted CD4+ T cells obtained from tumor infiltrating lymphocytes of a metastatic melanoma patient, we developed a novel TCR transgenic mouse with a C57BL/6 background. This HLA-A2 restricted TCR was positively selected on both CD4+ and CD8+ single-positive (SP) cells. However, when the TCR transgenic mouse was developed with an HLA-A2 background, the transgenic TCR was primarily expressed by CD3+CD4-CD8- double-negative (DN) T cells. TIL 1383I TCR transgenic CD4+, CD8+ and CD4-CD8- T cells were functional and retained the ability to control tumor growth without the need for vaccination or cytokine support in vivo. Furthermore, the HLA-A2+/human tyrosinase TCR double transgenic mice developed spontaneous hair depigmentation and had visual defects that progressed with age. Our data show that the expression of the high affinity TIL 1383I TCR alone in CD3+ T cells is sufficient to control the growth of murine and human melanoma and the presence or absence of CD4 and CD8 co-receptors had little effect on its functional capacity. PMID:22798675

Pontin functions as an essential coactivator for Oct4-dependent lincRNA expression in mouse embryonic stem cells.

PubMed

Boo, Kyungjin; Bhin, Jinhyuk; Jeon, Yoon; Kim, Joomyung; Shin, Hi-Jai R; Park, Jong-Eun; Kim, Kyeongkyu; Kim, Chang Rok; Jang, Hyonchol; Kim, In-Hoo; Kim, V Narry; Hwang, Daehee; Lee, Ho; Baek, Sung Hee

2015-04-10

The actions of transcription factors, chromatin modifiers and noncoding RNAs are crucial for the programming of cell states. Although the importance of various epigenetic machineries for controlling pluripotency of embryonic stem (ES) cells has been previously studied, how chromatin modifiers cooperate with specific transcription factors still remains largely elusive. Here, we find that Pontin chromatin remodelling factor plays an essential role as a coactivator for Oct4 for maintenance of pluripotency in mouse ES cells. Genome-wide analyses reveal that Pontin and Oct4 share a substantial set of target genes involved in ES cell maintenance. Intriguingly, we find that the Oct4-dependent coactivator function of Pontin extends to the transcription of large intergenic noncoding RNAs (lincRNAs) and in particular linc1253, a lineage programme repressing lincRNA, is a Pontin-dependent Oct4 target lincRNA. Together, our findings demonstrate that the Oct4-Pontin module plays critical roles in the regulation of genes involved in ES cell fate determination.

Three-dimensional imaging of nucleolin trafficking in normal cells, transfectants, and heterokaryons

NASA Astrophysics Data System (ADS)

Ballou, Byron T.; Fisher, Gregory W.; Deng, Jau-Shyong; Hakala, Thomas R.; Srivastava, Meera; Farkas, Daniel L.

1996-04-01

The study of intracellular trafficking using labeled molecules has been aided by the development of the cyanine fluorochromes, which are easily coupled, very soluble, resist photobleaching, and fluoresce at far-red wavelengths where background fluorescence is minimal. We have used Cy3-, Cy5-, and Cy5.5-labeled antibodies, antigen-binding fragments, and specifically binding single-stranded oligonucleotides to follow expression and trafficking of nucleolin, the most abundant protein of the nucleolus. Nucleolin shuttles between the nucleolus and the cytoplasm, and is also expressed on the cell surface, allowing us to test our techniques at all three cellular sites. Differentially cyanine-labeled non-specific antibodies were used to control for non-specific binding. Similarly, the differentially labeled non-binding strand of the cloned oligonucleotide served as a control. The multimode microscope allowed us to follow both rapid and slow redistributions of labeled ligands in the same study. We also performed 3-D reconstructions of nucleolin distribution in cells using rapid acquisition and deconvolution. Microinjection of labeled ligands was used to follow intracellular distribution, while incubation of whole cells with antibody and antigen-binding fragments was used to study uptake. To unambiguously define trafficking, and eliminate the possibility of interference by cross-reactive proteins, we transfected mouse renal cell carcinoma cells that express cell surface nucleolin with human nucleolin. We used microinjection and cell surface staining with Cy3- or Cy5- labeled monoclonal antibody D3 (specific for human nucleolin) to assess the cellular distribution of the human protein. Several clones expressed human nucleolin on their surfaces and showed high levels of transport of the human protein into the mouse nucleus and nucleolus. This distribution roughly parallels that of mouse nucleolin as determined by labeled polyclonal antibody. We have used these engineered transfectants to determine whether the cell surface-expressed xenogeneic nucleolin can serve as a target for antibodies in vivo.

Evaluation of stem cell reserve using serial bone marrow transplantation and competitive repopulation in a murine model of chronic hemolytic anemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maggio-Price, L.; Wolf, N.S.; Priestley, G.V.

1988-09-01

Serial transplantation and competitive repopulation were used to evaluate any loss of self-replicative capacity of bone marrow stem cells in a mouse model with increased and persistent hemopoietic demands. Congenic marrows from old control and from young and old mice with hereditary spherocytic anemia (sphha/sphha) were serially transplanted at 35-day intervals into normal irradiated recipients. Old anemic marrow failed or reverted to recipient karyotype at a mean of 3.5 transplants, and young anemic marrow reverted at a mean of 4.0 transplants, whereas controls did so at a mean of 5.0 transplants. In a competitive assay in which a mixture ofmore » anemic and control marrow was transplanted, the anemic marrow persisted to 10 months following transplantation; anemic marrow repopulation was greater if anemic marrow sex matched with the host. It is possible that lifelong stress of severe anemia decreases stem cell reserve in the anemic sphha/sphha mouse marrow. However, marginal differences in serial transplantation number and the maintenance of anemic marrow in a competition assay would suggest that marrow stem cells, under prolonged stress, are capable of exhibiting good repopulating and self-replicating abilities.« less

Gut endoderm takes flight from the wings of mesoderm.

PubMed

McDonald, Angela C H; Rossant, Janet

2014-12-01

The endoderm layer destined to be primitive gut is a mosaic of earlier visceral endoderm and definitive endoderm that arises later, during gastrulation. Live imaging now reveals that in mouse embryos, definitive endoderm cells egress from underlying mesoderm and intercalate into the overlying cell layer. This process requires SOX17-mediated control of basement membrane organization.

Chromatin associated Sin3A is essential for male germ cell lineage in the mouse

PubMed Central

Pellegrino, Jessica; Castrillon, Diego H.; David, Gregory

2012-01-01

Spermatogenesis is a complex process that requires coordinated proliferation and differentiation of male germ cells. The molecular events that dictate this process are largely unknown, but are likely to involve highly regulated transcriptional control. In this study, we investigate the contribution of chromatin associated Sin3A in mouse germ cell lineage development. Genetic inactivation of Sin3A in the male germline leads to sterility that results from the early and penetrant apoptotic death observed in Sin3A-deleted germ cells, coincident with the reentry in mitosis. Sin3A-deleted testes exhibit a Sertoli-cell only phenotype, consistent with the absolute requirement for Sin3A in germ cells’ development and/or viability. Interestingly, transcripts analysis revealed that the expression program of Sertoli cells is altered upon inactivation of Sin3A in germ cells. These studies identified a central role for the mammalian Sin3-HDAC complex in the germ cell lineage, and point to an exquisite transcriptional crosstalk between germ cells and their niche to support fertility in mammals. PMID:22820070

RanBPM (RanBP9) regulates mouse c-Kit receptor level and is essential for normal development of bone marrow progenitor cells

PubMed Central

Singh, Satyendra; Klarmann, Kimberly D.; Coppola, Vincenzo; Keller, Jonathan R.; Tessarollo, Lino

2016-01-01

c-Kit is a tyrosine kinase receptor important for gametogenesis, hematopoiesis, melanogenesis and mast cell biology. Dysregulation of c-Kit function is oncogenic and its expression in the stem cell niche of a number of tissues has underlined its relevance for regenerative medicine and hematopoietic stem cell biology. Yet, very little is known about the mechanisms that control c-Kit protein levels. Here we show that the RanBPM/RanBP9 scaffold protein binds to c-Kit and is necessary for normal c-Kit protein expression in the mouse testis and subset lineages of the hematopoietic system. RanBPM deletion causes a reduction in c-Kit protein but not its mRNA suggesting a posttranslational mechanism. This regulation is specific to the c-Kit receptor since RanBPM reduction does not affect other membrane proteins examined. Importantly, in both mouse hematopoietic system and testis, RanBPM deficiency causes defects consistent with c-Kit loss of expression suggesting that RanBPM is an important regulator of c-Kit function. The finding that this regulatory mechanism is also present in human cells expressing endogenous RanBPM and c-Kit suggests a potential new strategy to target oncogenic c-Kit in malignancies. PMID:27835883

RanBPM (RanBP9) regulates mouse c-Kit receptor level and is essential for normal development of bone marrow progenitor cells.

PubMed

Puverel, Sandrine; Kiris, Erkan; Singh, Satyendra; Klarmann, Kimberly D; Coppola, Vincenzo; Keller, Jonathan R; Tessarollo, Lino

2016-12-20

c-Kit is a tyrosine kinase receptor important for gametogenesis, hematopoiesis, melanogenesis and mast cell biology. Dysregulation of c-Kit function is oncogenic and its expression in the stem cell niche of a number of tissues has underlined its relevance for regenerative medicine and hematopoietic stem cell biology. Yet, very little is known about the mechanisms that control c-Kit protein levels. Here we show that the RanBPM/RanBP9 scaffold protein binds to c-Kit and is necessary for normal c-Kit protein expression in the mouse testis and subset lineages of the hematopoietic system. RanBPM deletion causes a reduction in c-Kit protein but not its mRNA suggesting a posttranslational mechanism. This regulation is specific to the c-Kit receptor since RanBPM reduction does not affect other membrane proteins examined. Importantly, in both mouse hematopoietic system and testis, RanBPM deficiency causes defects consistent with c-Kit loss of expression suggesting that RanBPM is an important regulator of c-Kit function. The finding that this regulatory mechanism is also present in human cells expressing endogenous RanBPM and c-Kit suggests a potential new strategy to target oncogenic c-Kit in malignancies.

The subcortical maternal complex controls symmetric division of mouse zygotes by regulating F-actin dynamics.

PubMed

Yu, Xing-Jiang; Yi, Zhaohong; Gao, Zheng; Qin, Dandan; Zhai, Yanhua; Chen, Xue; Ou-Yang, Yingchun; Wang, Zhen-Bo; Zheng, Ping; Zhu, Min-Sheng; Wang, Haibin; Sun, Qing-Yuan; Dean, Jurrien; Li, Lei

2014-09-11

Maternal effect genes play critical roles in early embryogenesis of model organisms where they have been intensively investigated. However, their molecular function in mammals remains largely unknown. Recently, we identified a subcortical maternal complex (SCMC) that contains four proteins encoded by maternal effect genes (Mater, Filia, Floped and Tle6). Here we report that TLE6, similar to FLOPED and MATER, stabilizes the SCMC and is necessary for cleavage beyond the two-cell stage of development. We document that the SCMC is required for formation of the cytoplasmic F-actin meshwork that controls the central position of the spindle and ensures symmetric division of mouse zygotes. We further demonstrate that the SCMC controls formation of the actin cytoskeleton specifically via Cofilin, a key regulator of F-actin assembly. Our results provide molecular insight into the physiological function of TLE6, its interaction with the SCMC and their roles in the symmetric division of the zygote in early mouse development.

Epidermal growth factor stimulates mouse placental lactogen I but inhibits mouse placental lactogen II secretion in vitro.

PubMed Central

Yamaguchi, M; Ogren, L; Endo, H; Thordarson, G; Kensinger, R; Talamantes, F

1992-01-01

This study was undertaken to determine whether epidermal growth factor (EGF) regulates the secretion of mouse placental lactogen (mPL)-I and mPL-II. Primary cell cultures were prepared from placentas from days 7, 9, and 11 of pregnancy and cultured for up to 5 days. Addition of EGF (20 ng/ml) to the medium resulted in significant stimulation of mPL-I secretion by the second day of culture in cells from days 7 and 9 of pregnancy and significant inhibition of mPL-II secretion by the third or fourth day of culture in cells from days 7, 9, and 11. Dose-response studies carried out with cells from day 7 of pregnancy demonstrated that the minimum concentration of EGF that stimulated mPL-I secretion and inhibited mPL-II secretion was 1.0 ng/ml. EGF did not affect the DNA content of the cells or cell viability, assessed by trypan blue exclusion, nor did it have a general effect on protein synthesis. There are three types of PL-containing giant cells in mouse placental cell cultures: cells that contain either mPL-I or mPL-II and cells that contain both hormones. Immunocytochemical analysis and the reverse hemolytic plaque assay indicated that EGF treatment was accompanied by a significant increase in the number of cells that produce mPL-I, but among the PL cells that contained mPL-I, there was no change in the fraction of cells that contained only mPL-I or the fraction that contained both mPL-I and mPL-II. In contrast, EGF treatment did affect the distribution of mPL-II among PL cells. In control cultures, about 75% of the cells that contained mPL-II also contained mPL-I, but in EGF-treated cultures, all of the cells that contained mPL-II also contained mPL-I. These data suggest that EGF regulates mPL-I and mPL-II secretion at least partly by regulating PL cell differentiation. PMID:1454826

Mouse neuroblastoma cell-based model and the effect of epileptic events on calcium oscillations and neural spikes

NASA Astrophysics Data System (ADS)

Kim, Suhwan; Jung, Unsang; Baek, Juyoung; Lee, Sangwon; Jung, Woonggyu; Kim, Jeehyun; Kang, Shinwon

2013-01-01

Recently, mouse neuroblastoma cells have been considered as an attractive model for the study of human neurological and prion diseases, and they have been intensively used as a model system in different areas. For example, the differentiation of neuro2a (N2A) cells, receptor-mediated ion current, and glutamate-induced physiological responses have been actively investigated with these cells. These mouse neuroblastoma N2A cells are of interest because they grow faster than other cells of neural origin and have a number of other advantages. The calcium oscillations and neural spikes of mouse neuroblastoma N2A cells in epileptic conditions are evaluated. Based on our observations of neural spikes in these cells with our proposed imaging modality, we reported that they can be an important model in epileptic activity studies. We concluded that mouse neuroblastoma N2A cells produce epileptic spikes in vitro in the same way as those produced by neurons or astrocytes. This evidence suggests that increased levels of neurotransmitter release due to the enhancement of free calcium from 4-aminopyridine causes the mouse neuroblastoma N2A cells to produce epileptic spikes and calcium oscillations.

Using the mouse embryonic stem cell test (EST) to evaluate the embryotoxicity of haloacetic acids

EPA Science Inventory

The Embryonic Stem Cell Test (EST) is used to predict the embryotoxic potential of a test compound by combining the data from cytotoxicity assays in undifferentiated mouse embryonic stem (mES) cells and differentiated mouse cells with the data from a differentiation assay in mES ...

Analysis of Alternative Pre-RNA Splicing in the Mouse Retina Using a Fluorescent Reporter.

PubMed

Murphy, Daniel; Kolandaivelu, Saravanan; Ramamurthy, Visvanathan; Stoilov, Peter

2016-01-01

In vivo alternative splicing is controlled in a tissue and cell type specific manner. Often individual cellular components of complex tissues will express different splicing programs. Thus, when studying splicing in multicellular organisms it is critical to determine the exon inclusion levels in individual cells positioned in the context of their native tissue or organ. Here we describe how a fluorescent splicing reporter in combination with in vivo electroporation can be used to visualize alternative splicing in individual cells within mature tissues. In a test case we show how the splicing of a photoreceptor specific exon can be visualized within the mouse retina. The retina was chosen as an example of a complex tissue that is fragile and whose cells cannot be studied in culture. With minor modifications to the injection and electroporation procedure, the protocol we outline can be applied to other tissues and organs.

Molecular mechanisms and functions of pyroptosis, inflammatory caspases and inflammasomes in infectious diseases

PubMed Central

Man, Si Ming; Karki, Rajendra; Kanneganti, Thirumala-Devi

2017-01-01

SUMMARY Cell death is a fundamental biological phenomenon that is essential for the survival and development of an organism. Emerging evidence also indicate that cell death contributes to immune defense against infectious diseases. Pyroptosis is a form of inflammatory programed cell death pathway activated by human and mouse caspase-1, human caspase-4 and caspase-5, or mouse caspase-11. These inflammatory caspases are used by the host to control bacterial, viral, fungal or protozoan pathogens. Pyroptosis requires cleavage and activation of the pore-forming effector protein gasdermin D by inflammatory caspases. Physical rupture of the cell causes release of the pro-inflammatory cytokines IL-1β and IL-18, alarmins and endogenous danger-associated molecular patterns, signifying the inflammatory potential of pyroptosis. Here, we describe the central role of inflammatory caspases and pyroptosis in mediating immunity to infection and clearance of pathogens. PMID:28462526

A transcription factor collective defines the HSN serotonergic neuron regulatory landscape

PubMed Central

Artacho, Alejandro; Jimeno-Martín, Ángela; Chirivella, Laura; Weinberg, Peter

2018-01-01

Cell differentiation is controlled by individual transcription factors (TFs) that together activate a selection of enhancers in specific cell types. How these combinations of TFs identify and activate their target sequences remains poorly understood. Here, we identify the cis-regulatory transcriptional code that controls the differentiation of serotonergic HSN neurons in Caenorhabditis elegans. Activation of the HSN transcriptome is directly orchestrated by a collective of six TFs. Binding site clusters for this TF collective form a regulatory signature that is sufficient for de novo identification of HSN neuron functional enhancers. Among C. elegans neurons, the HSN transcriptome most closely resembles that of mouse serotonergic neurons. Mouse orthologs of the HSN TF collective also regulate serotonergic differentiation and can functionally substitute for their worm counterparts which suggests deep homology. Our results identify rules governing the regulatory landscape of a critically important neuronal type in two species separated by over 700 million years. PMID:29553368

Cytoplasmic removal, enucleation, and cell fusion of mouse oocytes.

PubMed

Kyogoku, Hirohisa; Yoshida, Shuhei; Kitajima, Tomoya S

2018-01-01

Meiotic divisions in females occur in fully grown oocytes that have a large cytoplasmic volume. The intracellular processes that are needed to accomplish meiotic divisions, such as spindle formation, chromosome segregation, and polar body extrusion, are controlled by the concerted actions of nuclear and cytoplasmic factors, which exhibit dynamic quantitative and spatiotemporal changes during meiotic maturation. Thus, distinguishing between meiotic controls that are mediated by cytoplasmic factors and those mediated by nuclear factors helps in the understanding of the mechanisms underlying meiotic divisions. Here, we describe a method to artificially modify the number of nuclei and the volume of the cytoplasm of mouse oocytes through cytoplasmic removal, enucleation, and cell fusion. The oocytes generated by this method are viable and undergo reproducible meiotic divisions exhibiting the effects of altered amounts of cytoplasmic and nuclear factors, which can be analyzed by various assays, such as live imaging microscopy. © 2018 Elsevier Inc. All rights reserved.

Differentiation of sow and mouse ovarian granulosa cells exposed to zearalenone in vitro using RNA-seq gene expression.

PubMed

Zhang, Guo-Liang; Song, Jun-Lin; Zhou, Yi; Zhang, Rui-Qian; Cheng, Shun-Feng; Sun, Xiao-Feng; Qin, Guo-Qing; Shen, Wei; Li, Lan

2018-07-01

Zearalenone (ZEA), a natural contaminant found in feed, has been shown to have a negative impact on domestic animal reproduction, particularly in pigs. There are species-specific differences in the ZEA-induced toxicity pattern. Here, we investigated the different biological effects of ZEA exposure on porcine and mouse granulosa cells, using RNA-seq analysis. We treated murine and porcine granulosa cells with 10 μM and 30 μM ZEA during 72 h of culturing, in vitro. The results showed that 10 μM ZEA exposure significantly altered mitosis associated genes in porcine granulosa cells, while the same treatment significantly altered the steroidogenesis associated genes in mouse granulosa cells. Exposure to 30 μM ZEA resulted in significantly up-regulated expression of inflammatory related genes in porcine granulosa cells as well as the cancer related genes in mouse granulosa cells. Similarly, 30 μM ZEA exposure significantly decreased the expression of tumor suppressor factors in the mouse granulosa cells. Furthermore, immunofluorescence, RT-qPCR as well as western-blot analysis verified the different expression of related genes in ZEA exposed porcine and mouse granulosa cells. Collectively, these results illustrate the presence of species differences with regards to ZEA effects between porcine and mouse ovarian granulosa cells, in vitro. Copyright © 2018 Elsevier Inc. All rights reserved.

The replication of a mouse adapted SARS-CoV in a mouse cell line stably expressing the murine SARS-CoV receptor mACE2 efficiently induces the expression of proinflammatory cytokines.

PubMed

Regla-Nava, Jose A; Jimenez-Guardeño, Jose M; Nieto-Torres, Jose L; Gallagher, Thomas M; Enjuanes, Luis; DeDiego, Marta L

2013-11-01

Infection of conventional mice with a mouse adapted (MA15) severe acute respiratory syndrome (SARS) coronavirus (CoV) reproduces many aspects of human SARS such as pathological changes in lung, viremia, neutrophilia, and lethality. However, established mouse cell lines highly susceptible to mouse-adapted SARS-CoV infection are not available. In this work, efficiently transfectable mouse cell lines stably expressing the murine SARS-CoV receptor angiotensin converting enzyme 2 (ACE2) have been generated. These cells yielded high SARS-CoV-MA15 titers and also served as excellent tools for plaque assays. In addition, in these cell lines, SARS-CoV-MA15 induced the expression of proinflammatory cytokines and IFN-β, mimicking what has been observed in experimental animal models infected with SARS-CoV and SARS patients. These cell lines are valuable tools to perform in vitro studies in a mouse cell system that reflects the species used for in vivo studies of SARS-CoV-MA15 pathogenesis. Copyright © 2013 Elsevier B.V. All rights reserved.

The terminator mouse: salvation for primary cell culture.

PubMed

Kabgani, Nazanin; Moeller, Marcus J

2013-11-01

The Terminator had to come back from the future already several times in an effort to bring salvation to mankind. In the present issue of Kidney International, Guo et al. brought us a novel transgenic mouse model: the terminator mouse. This highly elegant mouse may facilitate significantly the derivation of primary cultures of a specific cell type from a tissue containing multiple cell populations.

The Orphan Nuclear Receptor TLX/NR2E1 in Neural Stem Cells and Diseases.

PubMed

Wang, Tao; Xiong, Jian-Qiong

2016-02-01

The human TLX gene encodes an orphan nuclear receptor predominantly expressed in the central nervous system. Tailess and Tlx, the TLX homologues in Drosophila and mouse, play essential roles in body-pattern formation and neurogenesis during early embryogenesis and perform crucial functions in maintaining stemness and controlling the differentiation of adult neural stem cells in the central nervous system, especially the visual system. Multiple target genes and signaling pathways are regulated by TLX and its homologues in specific tissues during various developmental stages. This review aims to summarize previous studies including many recent updates from different aspects concerning TLX and its homologues in Drosophila and mouse.

Controlling Mitochondrial Dynamics to Mitigate Noise-Induced Hearing Loss

DTIC Science & Technology

2016-10-01

exposure significantly reduced noise-induced auditory threshold shifts in our mouse model of NIHL. Additionally, protection against outer hair cell...and at 6 hours post-noise exposure. ‐ Perform analysis of outer auditory hair cells and synaptic ribbons from the different treatment groups...have made progress towards the completion of the outer hair cell counts (OHC) for this Subtask, particularly for study groups (1) mdivi-1/vehicle, and

Genetically engineered mouse models for studying inflammatory bowel disease.

PubMed

Mizoguchi, Atsushi; Takeuchi, Takahito; Himuro, Hidetomo; Okada, Toshiyuki; Mizoguchi, Emiko

2016-01-01

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that is mediated by very complex mechanisms controlled by genetic, immune, and environmental factors. More than 74 kinds of genetically engineered mouse strains have been established since 1993 for studying IBD. Although mouse models cannot fully reflect human IBD, they have provided significant contributions for not only understanding the mechanism, but also developing new therapeutic means for IBD. Indeed, 20 kinds of genetically engineered mouse models carry the susceptibility genes identified in human IBD, and the functions of some other IBD susceptibility genes have also been dissected out using mouse models. Cutting-edge technologies such as cell-specific and inducible knockout systems, which were recently employed to mouse IBD models, have further enhanced the ability of investigators to provide important and unexpected rationales for developing new therapeutic strategies for IBD. In this review article, we briefly introduce 74 kinds of genetically engineered mouse models that spontaneously develop intestinal inflammation. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Response of a mouse hybridoma cell line to heat shock, agitation, and sparging

NASA Technical Reports Server (NTRS)

Passini, Cheryl A.; Goochee, Charles F.

1989-01-01

A mouse hybridoma cell line is used as a model system for studying the effect of environmental stress on attachment-independent mammalian cells. The full time course of recovery for a mouse hybridoma cell line from both a mild and intermediate heat shock is examined. The pattern of intracellular synthesis is compared for actively growing, log phase cells and nondividing, stationary phase cells.

[Low expression of activin A in mouse and human embryonic teratocarcinoma cells].

PubMed

Gordeeva, O F

2014-01-01

TGFP3 family factors play an important role in regulating the balance of self-renewal and differentiation of mouse and human pluripotent stem and embryonic teratocarcinoma cells. The expression patterns of TGFbeta family signaling ligands and functional roles of these signaling pathways differ significantly in mouse and human embryonic stem cells, but the activity and functional role of these factors in mouse and human embryonic teratocarcinoma cells were not sufficiently investigated. Comparative quantitative real-time PCR analysis of the expression of TGF@[beta] family factors in mouse embryonic stem, embryonic germ, and embryonic teratocarcinoma cells showed that embryonic teratocarcinoma cells express lower ActivinA than pluripotent stem cells but similar levels of factors Nodal, Lefty 1, TGFbeta1, BMP4, and GDF3. In human nullipotent embryonic teratocarcinoma PA-1 cells, most factors of the TGFbeta family (ACTIVINA, NODAL, LEFTY 1, BMP4, and GDF3) are expressed at lower levels than in human embryonic stem cells: Thus, in mouse and human nullipotent teratocarcinoma cells, theexpression of ActivinA is significantly reduced com- pared ivith embryonic stem cells. Presumably, these differences may be associated with changes in the functional activity of the respective signaling pathways and deregulation of proliferative and antiproliferative mechanisms in embryonic teratocarcinoma cells.

Differential effects of α4β7 and GPR15 on homing of effector and regulatory T cells from patients with UC to the inflamed gut in vivo.

PubMed

Fischer, Anika; Zundler, Sebastian; Atreya, Raja; Rath, Timo; Voskens, Caroline; Hirschmann, Simon; López-Posadas, Rocío; Watson, Alastair; Becker, Christoph; Schuler, Gerold; Neufert, Clemens; Atreya, Imke; Neurath, Markus F

2016-10-01

Gut homing of lymphocytes via adhesion molecules has recently emerged as new target for therapy in IBDs. We aimed to analyse the in vivo homing of effector (Teff) and regulatory (Treg) T cells to the inflamed gut via α4β7 and G protein receptor GPR15. We assessed the expression of homing receptors on T cells in peripheral blood and inflamed mucosa. We studied the migration pattern and homing of Teff and Treg cells to the inflamed gut using intravital confocal microscopy and FACS in a humanised mouse model in dextran sodium sulfate-treated NSG (NOD.Cg-Prkdcscid-Il2rgtm1Wjl/SzJ) mice. Expression of GPR15 and α4β7 was significantly increased on Treg rather than Teff cells in peripheral blood of patients with UC as compared with Crohn's disease and controls. In vivo analysis in a humanised mouse model showed augmented gut homing of UC Treg cells as compared with controls. Moreover, suppression of UC (but not control) Teff and Treg cell homing was noted upon treatment with the α4β7 antibody vedolizumab. In contrast, siRNA blockade of GPR15 had only effects on homing of Teff cells but did not affect Treg homing in UC. Clinical vedolizumab treatment was associated with marked expansion of UC Treg cells in peripheral blood. α4β7 rather than GPR15 is crucial for increased colonic homing of UC Treg cells in vivo, while both receptors control UC Teff cell homing. Vedolizumab treatment impairs homing of UC Treg cells leading to their accumulation in peripheral blood with subsequent suppression of systemic Teff cell expansion. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Near-infrared laser irradiation improves the development of mouse pre-implantation embryos.

PubMed

Yokoo, Masaki; Mori, Miho

2017-05-27

The aim of the present study was to assess the effects of near-infrared laser irradiation on the in vitro development of mouse embryos. Female ICR mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin (hCG), and mated with male mice. Two-cell stage embryos were collected 40 h after administering hCG and cultured in M16 medium. Two-cell embryos (0 h after culture), 8-cell embryos (approx. 30 h after culture), morula (approx. 48 h after culture), and blastocysts (approx. 73 h after culture) were irradiated at 904 nm for 60 s. These embryos were cultured in a time-lapse monitoring system and the timing of blastocyst hatching was evaluated. Some of the irradiated blastocysts were transferred to the uterine horns of pseudopregnant recipients immediately after irradiation. Pregnancy rates, and offspring growth and fertility, were evaluated. Near-infrared laser irradiation increased the speed of in vitro mouse embryo development. In irradiated blastocysts, hatching was faster than in control (non-irradiated) blastocysts (18.4 vs. 28.2 h, P < 0.05). When 195 irradiated blastocysts were transferred to 18 pseudopregnant mice, all became pregnant and 92 (47.2%) normal-looking pups were born alive. When 182 control blastocysts were transferred to 17 pseudopregnant mice, 14 (82.4%) became pregnant and 54 (29.7%) normal-looking pups were born alive. The growth trajectories (up to 5 weeks) of offspring from irradiated blastocysts were similar to those from control blastocysts. Second generation offspring from transplanted animals were all fertile. These results indicate that near-infrared laser irradiation improves the quality of mouse embryo development in vitro, and increases the live birth rate without affecting the normality of the offspring. Thus, the near-infrared laser method may enhance the quality of embryos and contribute to improvements in reproductive technologies in mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

Transgenic mouse lines for non-invasive ratiometric monitoring of intracellular chloride

PubMed Central

Batti, Laura; Mukhtarov, Marat; Audero, Enrica; Ivanov, Anton; Paolicelli, Rosa Chiara; Zurborg, Sandra; Gross, Cornelius; Bregestovski, Piotr; Heppenstall, Paul A.

2013-01-01

Chloride is the most abundant physiological anion and participates in a variety of cellular processes including trans-epithelial transport, cell volume regulation, and regulation of electrical excitability. The development of tools to monitor intracellular chloride concentration ([Cli]) is therefore important for the evaluation of cellular function in normal and pathological conditions. Recently, several Cl-sensitive genetically encoded probes have been described which allow for non-invasive monitoring of [Cli]. Here we describe two mouse lines expressing a CFP-YFP-based Cl probe called Cl-Sensor. First, we generated transgenic mice expressing Cl-Sensor under the control of the mouse Thy1 mini promoter. Cl-Sensor exhibited good expression from postnatal day two (P2) in neurons of the hippocampus and cortex, and its level increased strongly during development. Using simultaneous whole-cell monitoring of ionic currents and Cl-dependent fluorescence, we determined that the apparent EC50 for Cli was 46 mM, indicating that this line is appropriate for measuring neuronal [Cli] in postnatal mice. We also describe a transgenic mouse reporter line for Cre-dependent conditional expression of Cl-Sensor, which was targeted to the Rosa26 locus and by incorporating a strong exogenous promoter induced robust expression upon Cre-mediated recombination. We demonstrate high levels of tissue-specific expression in two different Cre-driver lines targeting cells of the myeloid lineage and peripheral sensory neurons. Using these mice the apparent EC50 for Cli was estimated to be 61 and 54 mM in macrophages and DRG, respectively. Our data suggest that these mouse lines will be useful models for ratiometric monitoring of Cli in specific cell types in vivo. PMID:23734096

TREATMENT OF STROKE WITH DETA-NONOATE AND BONE MARROW STROMAL CELLS UPREGULATES ANGIOPOIETIN-1/TIE2 AND ENHANCES NEOVASCULARIZATION

PubMed Central

CUI, X.; CHEN, J.; ZACHAREK, A.; ROBERTS, C.; SAVANT-BHONSALE, S.; CHOPP, M.

2008-01-01

Neovascularization may contribute to functional recovery after neural injury. Combination treatment of stroke with a nitric oxide donor, DETA-NONOate and bone marrow stromal cells promote functional recovery. However, the mechanisms underlying functional improvement have not been elucidated. In this study, we tested the hypothesis that combination treatment upregulates Angiopoietin1 and its receptor Tie2 in the ischemic brain and bone marrow stromal cells, thereby enhances cerebral neovascularization after stroke. Adult wild type male C57BL/6 mice were intravenously administered PBS, bone marrow stromal cells 5×105, DETA-NONOate 0.4 mg/kg or combination DETA-NONOate with bone marrow stromal cells (n=12/group) after middle cerebral artery occlusion. Combination treatment significantly upregulated Angiopoietin-1/Tie2 and tight junction protein (occludin) expression, and increased the number, diameter and perimeter of blood vessels in the ischemic brain compared with vehicle control (mean ± SE, p<0.05). In vitro, DETA-NONOate significantly increased Angiopoietin-1/Tie2 protein (n=6/group) and Tie2 mRNA (n=3/group) expression in bone marrow stromal cells. DETA-NONOate also significantly increased Angiopoietin-1 protein (n=6/group) and mRNA (n=3/group) expression in mouse brain endothelial cells (p<0.05). Angiopoietin-1 mRNA (n=3/group) was significantly increased in mouse brain endothelial cells treated with DETA-NONOate in combination with bone marrow stromal cells conditioned medium compared with cells treated with bone marrow stromal cells conditioned medium or DETA-NONOate alone. Mouse brain endothelial cell capillary tube-like formation assays (n=6/group) showed that Angiopoietin-1 peptide, the supernatant of bone marrow stromal cells and DETA-NONOate significantly increased capillary tube formation compared to vehicle control. Combination treatment significantly increased capillary tube formation compared with DETA-NONOate treatment alone. Inhibition of Angiopoietin-1 significantly attenuated combination treatment-induced tube formation. Our data indicated that combination treatment of stroke with DETA-NONOate and bone marrow stromal cells promotes neovascularization, which is at least partially mediated by upregulation of the Angiopoietin-1/Tie2 axis. PMID:18691637

Abnormal Interactions between Perifollicular Mast Cells and CD8+ T-Cells May Contribute to the Pathogenesis of Alopecia Areata

PubMed Central

Bertolini, Marta; Zilio, Federica; Rossi, Alfredo; Gilhar, Amos; Keren, Aviad; Meyer, Katja C.; Wang, Eddy; Funk, Wolfgang; McElwee, Kevin; Paus, Ralf

2014-01-01

Alopecia areata (AA) is a CD8+ T-cell dependent autoimmune disease of the hair follicle (HF) in which the collapse of HF immune privilege (IP) plays a key role. Mast cells (MCs) are crucial immunomodulatory cells implicated in the regulation of T cell-dependent immunity, IP, and hair growth. Therefore, we explored the role of MCs in AA pathogenesis, focusing on MC interactions with CD8+ T-cells in vivo, in both human and mouse skin with AA lesions. Quantitative (immuno-)histomorphometry revealed that the number, degranulation and proliferation of perifollicular MCs are significantly increased in human AA lesions compared to healthy or non-lesional control skin, most prominently in subacute AA. In AA patients, perifollicular MCs showed decreased TGFβ1 and IL-10 but increased tryptase immunoreactivity, suggesting that MCs switch from an immuno-inhibitory to a pro-inflammatory phenotype. This concept was supported by a decreased number of IL-10+ and PD-L1+ MCs, while OX40L+, CD30L+, 4–1BBL+ or ICAM-1+ MCs were increased in AA. Lesional AA-HFs also displayed significantly more peri- and intrafollicular- CD8+ T-cells as well as more physical MC/CD8+ T-cell contacts than healthy or non-lesional human control skin. During the interaction with CD8+ T-cells, AA MCs prominently expressed MHC class I and OX40L, and sometimes 4–1BBL or ICAM-1, suggesting that MC may present autoantigens to CD8+ T-cells and/or co-stimulatory signals. Abnormal MC numbers, activities, and interactions with CD8+ T-cells were also seen in the grafted C3H/HeJ mouse model of AA and in a new humanized mouse model for AA. These phenomenological in vivo data suggest the novel AA pathobiology concept that perifollicular MCs are skewed towards pro-inflammatory activities that facilitate cross-talk with CD8+ T-cells in this disease, thus contributing to triggering HF-IP collapse in AA. If confirmed, MCs and their CD8+ T-cell interactions could become a promising new therapeutic target in the future management of AA. PMID:24832234

Choline Availability During Embryonic Development Alters Progenitor Cell Mitosis in Developing Mouse Hippocampus1,2

PubMed Central

Craciunescu, Corneliu N.; Albright, Craig D.; Mar, Mei-Heng; Song, Jiannan; Zeisel, Steven H.

2006-01-01

Previously, we reported that dietary choline influences development of the hippocampus in fetal rat brain. It is important to know whether similar effects of choline occur in developing fetal mouse brain because interesting new experimental approaches are now available using several transgenic mouse models. Timed-pregnant mice were fed choline-supplemented (CS), control (CT) or choline-deficient (CD) AIN-76 diet from embryonic day 12 to 17 (E12–17). Fetuses from CD dams had diminished concentrations of phosphocholine and phosphatidylcholine in their brains compared with CT or CS fetuses (P < 0.05). When we analyzed fetal hippocampus on day E17 for cells with mitotic phase–specific expression of phosphorylated histone H3, we detected fewer labeled cells at the ventricular surface of the ventricular zone in the CD group (14.8 ± 1.9) compared with the CT (30.7 ± 1.9) or CS (36.6 ± 2.6) group (P < 0.05). At the same time, we detected more apoptotic cells in E17 hippocampus using morphology in the CD group (11.8 ± 1.4) than in CT (5.6 ± 0.6) or CS (4.2 ± 0.7) group (P < 0.05). This was confirmed using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin anti-digoxigenin fluorescein conjugate antibody nick end-labeling (TUNEL) and activated caspase-3 immunoreactivity. We conclude that the dietary availability of choline to the mouse dam influences progenitor cell proliferation and apoptosis in the fetal brain. J. Nutr. 133: 3614–3618, 2003. PMID:14608083

Choroid Sprouting Assay: An Ex Vivo Model of Microvascular Angiogenesis

PubMed Central

Shao, Zhuo; Friedlander, Mollie; Hurst, Christian G.; Cui, Zhenghao; Pei, Dorothy T.; Evans, Lucy P.; Juan, Aimee M.; Tahir, Houda; Duhamel, François; Chen, Jing; Sapieha, Przemyslaw; Chemtob, Sylvain; Joyal, Jean-Sébastien; Smith, Lois E. H.

2013-01-01

Angiogenesis of the microvasculature is central to the etiology of many diseases including proliferative retinopathy, age-related macular degeneration and cancer. A mouse model of microvascular angiogenesis would be very valuable and enable access to a wide range of genetically manipulated tissues that closely approximate small blood vessel growth in vivo. Vascular endothelial cells cultured in vitro are widely used, however, isolating pure vascular murine endothelial cells is technically challenging. A microvascular mouse explant model that is robust, quantitative and can be reproduced without difficulty would overcome these limitations. Here we characterized and optimized for reproducibility an organotypic microvascular angiogenesis mouse and rat model from the choroid, a microvascular bed in the posterior of eye. The choroidal tissues from C57BL/6J and 129S6/SvEvTac mice and Sprague Dawley rats were isolated and incubated in Matrigel. Vascular sprouting was comparable between choroid samples obtained from different animals of the same genetic background. The sprouting area, normalized to controls, was highly reproducible between independent experiments. We developed a semi-automated macro in ImageJ software to allow for more efficient quantification of sprouting area. Isolated choroid explants responded to manipulation of the external environment while maintaining the local interactions of endothelial cells with neighboring cells, including pericytes and macrophages as evidenced by immunohistochemistry and fluorescence-activated cell sorting (FACS) analysis. This reproducible ex vivo angiogenesis assay can be used to evaluate angiogenic potential of pharmacologic compounds on microvessels and can take advantage of genetically manipulated mouse tissue for microvascular disease research. PMID:23922736

Potential Role for ADAM15 in Pathological Neovascularization in Mice

PubMed Central

Horiuchi, Keisuke; Weskamp, Gisela; Lum, Lawrence; Hammes, Hans-Peter; Cai, Hui; Brodie, Thomas A.; Ludwig, Thomas; Chiusaroli, Riccardo; Baron, Roland; Preissner, Klaus T.; Manova, Katia; Blobel, Carl P.

2003-01-01

ADAM15 (named for a disintegrin and metalloprotease 15, metargidin) is a membrane-anchored glycoprotein that has been implicated in cell-cell or cell-matrix interactions and in the proteolysis of molecules on the cell surface or extracellular matrix. To characterize the potential roles of ADAM15 during development and in adult mice, we analyzed its expression pattern by mRNA in situ hybridization and generated mice carrying a targeted deletion of ADAM15 (adam15−/− mice). A high level of expression of ADAM15 was found in vascular cells, the endocardium, hypertrophic cells in developing bone, and specific areas of the hippocampus and cerebellum. However, despite the pronounced expression of ADAM15 in these tissues, no major developmental defects or pathological phenotypes were evident in adam15−/− mice. The elevated levels of ADAM15 in endothelial cells prompted an evaluation of its role in neovascularization. In a mouse model for retinopathy of prematurity, adam15−/− mice had a major reduction in neovascularization compared to wild-type controls. Furthermore, the size of tumors resulting from implanted B16F0 mouse melanoma cells was significantly smaller in adam15−/− mice than in wild-type controls. Since ADAM15 does not appear to be required for developmental angiogenesis or for adult homeostasis, it may represent a novel target for the design of inhibitors of pathological neovascularization. PMID:12897135

Transcript copy number estimation using a mouse whole-genome oligonucleotide microarray

PubMed Central

Carter, Mark G; Sharov, Alexei A; VanBuren, Vincent; Dudekula, Dawood B; Carmack, Condie E; Nelson, Charlie; Ko, Minoru SH

2005-01-01

The ability to quantitatively measure the expression of all genes in a given tissue or cell with a single assay is an exciting promise of gene-expression profiling technology. An in situ-synthesized 60-mer oligonucleotide microarray designed to detect transcripts from all mouse genes was validated, as well as a set of exogenous RNA controls derived from the yeast genome (made freely available without restriction), which allow quantitative estimation of absolute endogenous transcript abundance. PMID:15998450

Cell-penetrable mouse forkhead box protein 3 alleviates experimental arthritis in mice by up-regulating regulatory T cells.

PubMed

Liu, Xia; Ji, Baoju; Sun, Mengyi; Wu, Weijiang; Huang, Lili; Sun, Aihua; Zong, Yangyong; Xia, Sheng; Shi, Liyun; Qian, Hui; Xu, Wenrong; Shao, Qixiang

2015-07-01

Regulatory T cells (T(regs)) have potential applications in clinical disease therapy, such as autoimmune diseases and transplant rejection. However, their numbers are limited. Forkhead box protein 3 (FoxP3) is a key transcription factor that controls T(reg) development and function. Here, we generated a cell-permeable fusion protein, protein transduction domain (PTD)-conjugated mouse FoxP3 protein (PTD-mFoxP3), and evaluated whether PTD-mFoxp3 can alleviate rheumatoid arthritis (RA) in the collagen-induced arthritis (CIA) mouse model. As expected, PTD-mFoxP3 was transduced into cells effectively, and inhibited T cell activation and attenuated the cell proliferation. It decreased interleukin (IL) 2 and interferon (IFN)-γ expression, and increased IL-10 expression in activated CD4(+)CD25(-) T cells. PTD-mFoxP3-transduced CD4(+)CD25(-) T cells attenuated proliferation of activated CD4(+)CD25(-) T cells. In addition, PTD-mFoxP3 blocked the Th17 differentiation programme in vitro and down-regulated IL-17 production from T cells by modulating induction and levels of retinoid-related orphan receptor gamma t (RORγt). Intra-articular delivery of PTD-mFoxP3 delayed disease incidence remarkably and alleviated autoimmune symptoms of CIA mice. Moreover, protective effects of PTD-mFoxP3 were associated with regulating the balance of T helper type 17 (Th17) and T(regs). These results suggest that PTD-mFoxP3 may be a candidate for RA therapy. © 2015 British Society for Immunology.

Molecular cloning of the mouse gene coding for {alpha}{sub 2}-macroglobulin and targeting of the gene in embryonic stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Umans, L.; Serneels, L.; Hilliker, C.

1994-08-01

The authors have cloned the mouse gene coding for {alpha}{sub 2}-macroglobulin in overlapping {lambda} clones and have analyzed its structure. The gene contains 36 exons, coding for the 4.8-kb cDNA that we cloned previously. Including putative control elements in the 5{prime} flanking region, the gene covers about 45 kb. A region of 3.8 kb, stretching from 835 bases upstream of the cDNA start site to exon 4, including all intervening sequences, was sequenced completely. The analysis demonstrated that the putative promoter region of the mouse A2M gene differed considerably from the known promoter sequences of the human A2M gene andmore » of the rat acute-phas A2M gene. Comparison of the exon-intron structure of all known genes of the A2M family confirmed that the rat acute phase A2M gene is more closely related to the human gene than to the mouse A2M gene. To generate mice with the A2M gene inactivated, an insertion type of construct containing 7.5 kb of genomic DNA of the mouse strain 129/J, encompassing exons 16 to 19, was synthesized. A hygromycin marker gene was embedded in intron 17. After electroporation, 198 hygromycin-resistant ES cell lines were isolated and analyzed by Southern blotting. Five ES cell lines were obtained with one allele of the mouse A2M gene targeted by this insertion construct, demonstrating that the position and the characteristics of the vector served the intended goal.« less

Leptin regulation of bone resorption by the sympathetic nervous system and CART.

PubMed

Elefteriou, Florent; Ahn, Jong Deok; Takeda, Shu; Starbuck, Michael; Yang, Xiangli; Liu, Xiuyun; Kondo, Hisataka; Richards, William G; Bannon, Tony W; Noda, Masaki; Clement, Karine; Vaisse, Christian; Karsenty, Gerard

2005-03-24

Bone remodelling, the mechanism by which vertebrates regulate bone mass, comprises two phases, namely resorption by osteoclasts and formation by osteoblasts; osteoblasts are multifunctional cells also controlling osteoclast differentiation. Sympathetic signalling via beta2-adrenergic receptors (Adrb2) present on osteoblasts controls bone formation downstream of leptin. Here we show, by analysing Adrb2-deficient mice, that the sympathetic nervous system favours bone resorption by increasing expression in osteoblast progenitor cells of the osteoclast differentiation factor Rankl. This sympathetic function requires phosphorylation (by protein kinase A) of ATF4, a cell-specific CREB-related transcription factor essential for osteoblast differentiation and function. That bone resorption cannot increase in gonadectomized Adrb2-deficient mice highlights the biological importance of this regulation, but also contrasts sharply with the increase in bone resorption characterizing another hypogonadic mouse with low sympathetic tone, the ob/ob mouse. This discrepancy is explained, in part, by the fact that CART ('cocaine amphetamine regulated transcript'), a neuropeptide whose expression is controlled by leptin and nearly abolished in ob/ob mice, inhibits bone resorption by modulating Rankl expression. Our study establishes that leptin-regulated neural pathways control both aspects of bone remodelling, and demonstrates that integrity of sympathetic signalling is necessary for the increase in bone resorption caused by gonadal failure.

Cell-Specific Oxidative Stress and Cytotoxicity after Wildfire Coarse Particulate Matter Instillation into Mouse Lung

PubMed Central

Williams, Keisha M.; Franzi, Lisa M.; Last, Jerold A.

2012-01-01

Our previous work has shown that coarse particulate matter (PM10-2.5) from wildfire smoke is more toxic to lung macrophages on an equal dose (by mass) basis than coarse PM isolated from normal ambient air, as evidenced by decreased numbers of macrophages in lung lavage fluid 6 and 24 hours after PM instillation into mouse lungs in vivo and by cytotoxicity to a macrophage cell line observed directly in vitro. We hypothesized that pulmonary macrophages from mice instilled with wildfire coarse PM would undergo more cytotoxicity than macrophages from controls, and that there would be an increase in oxidative stress in their lungs. Cytotoxicity was quantified as decreased viable macrophages and increased percentages of dead macrophages in the bronchoalveolar lavage fluid (BALF) of mice instilled with wildfire coarse PM. At one hour after PM instillation, we observed both decreased numbers of viable macrophages and increased dead macrophage percentages as compared to controls. An increase in free isoprostanes, an indicator of oxidative stress, from control values of 28.1±3.2 pg/mL to 83.9±12.2 pg/mL was observed a half-hour after PM instillation. By one hour after PM instillation, isoprostane values had returned to 30.4±7.6pg/mL, not significantly different from control concentrations. Lung sections from mice instilled with wildfire coarse PM showed rapid Clara cell responses, with decreased intracellular staining for the Clara cell secretory protein CCSP 1 hour after wildfire PM instillation. In conclusion, very rapid cytotoxicity occurs in pulmonary macrophages and oxidative stress responses are seen 0.5-1 hour after wildfire coarse PM instillation. These results define early cellular and biochemical events occurring in vivo and support the hypothesis that oxidative stress-mediated macrophage toxicity plays a key role in the initial response of the mouse lung to wildfire PM exposure. PMID:23142465

Cell-specific oxidative stress and cytotoxicity after wildfire coarse particulate matter instillation into mouse lung.

PubMed

Williams, Keisha M; Franzi, Lisa M; Last, Jerold A

2013-01-01

Our previous work has shown that coarse particulate matter (PM(10-2.5)) from wildfire smoke is more toxic to lung macrophages on an equal dose (by mass) basis than coarse PM isolated from normal ambient air, as evidenced by decreased numbers of macrophages in lung lavage fluid 6 and 24hours after PM instillation into mouse lungs in vivo and by cytotoxicity to a macrophage cell line observed directly in vitro. We hypothesized that pulmonary macrophages from mice instilled with wildfire coarse PM would undergo more cytotoxicity than macrophages from controls, and that there would be an increase in oxidative stress in their lungs. Cytotoxicity was quantified as decreased viable macrophages and increased percentages of dead macrophages in the bronchoalveolar lavage fluid (BALF) of mice instilled with wildfire coarse PM. At 1hour after PM instillation, we observed both decreased numbers of viable macrophages and increased dead macrophage percentages as compared to controls. An increase in free isoprostanes, an indicator of oxidative stress, from control values of 28.1±3.2pg/mL to 83.9±12.2pg/mL was observed a half-hour after PM instillation. By 1hour after PM instillation, isoprostane values had returned to 30.4±7.6pg/mL, not significantly different from control concentrations. Lung sections from mice instilled with wildfire coarse PM showed rapid Clara cell responses, with decreased intracellular staining for the Clara cell secretory protein CCSP 1hour after wildfire PM instillation. In conclusion, very rapid cytotoxicity occurs in pulmonary macrophages and oxidative stress responses are seen 0.5-1hour after wildfire coarse PM instillation. These results define early cellular and biochemical events occurring in vivo and support the hypothesis that oxidative stress-mediated macrophage toxicity plays a key role in the initial response of the mouse lung to wildfire PM exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

Oxygen-controlled automated neural differentiation of mouse embryonic stem cells.

PubMed

Mondragon-Teran, Paul; Tostoes, Rui; Mason, Chris; Lye, Gary J; Veraitch, Farlan S

2013-03-01

Automation and oxygen tension control are two tools that provide significant improvements to the reproducibility and efficiency of stem cell production processes. the aim of this study was to establish a novel automation platform capable of controlling oxygen tension during both the cell-culture and liquid-handling steps of neural differentiation processes. We built a bespoke automation platform, which enclosed a liquid-handling platform in a sterile, oxygen-controlled environment. An airtight connection was used to transfer cell culture plates to and from an automated oxygen-controlled incubator. Our results demonstrate that our system yielded comparable cell numbers, viabilities, metabolism profiles and differentiation efficiencies when compared with traditional manual processes. Interestingly, eliminating exposure to ambient conditions during the liquid-handling stage resulted in significant improvements in the yield of MAP2-positive neural cells, indicating that this level of control can improve differentiation processes. This article describes, for the first time, an automation platform capable of maintaining oxygen tension control during both the cell-culture and liquid-handling stages of a 2D embryonic stem cell differentiation process.

Surface Antigens Common to Mouse Cleavage Embryos and Primitive Teratocarcinoma Cells in Culture

PubMed Central

Artzt, Karen; Dubois, Philippe; Bennett, Dorothea; Condamine, Hubert; Babinet, Charles; Jacob, François

1973-01-01

Syngeneic antisera have been produced in mouse strain 129/Sv-CP males against the primitive cells of teratocarcinoma. These sera react specifically with the primitive cells and are negative on various types of differentiated teratoma cells derived from the same original tumor. They are negative on all other mouse cells tested, with the exception of male germ cells and cleavage-stage embryos. Thus, teratoma cells possess cell-surface antigens in common with normal cleavage-stage embryos. Images PMID:4355379

Oral recombinant human or mouse lactoferrin reduces Mycobacterium tuberculosis TDM induced granulomatous lung pathology.

PubMed

Hwang, Shen-An; Kruzel, Marian L; Actor, Jeffrey K

2017-02-01

Trehalose 6'6-dimycolate (TDM) is the most abundant glycolipid on the cell wall of Mycobacterium tuberculosis (MTB). TDM is capable of inducing granulomatous pathology in mouse models that resembles those induced by MTB infection. Using the acute TDM model, this work investigates the effect of recombinant human and mouse lactoferrin to reduce granulomatous pathology. C57BL/6 mice were injected intravenously with TDM at a dose of 25 μg·mouse -1 . At day 4 and 6, recombinant human or mouse lactoferrin (1 mg·(100 μL) -1 ·mouse -1 ) were delivered by gavage. At day 7 after TDM injection, mice were evaluated for lung pathology, cytokine production, and leukocyte populations. Mice given human or mouse lactoferrin had reduced production of IL-12p40 in their lungs. Mouse lactoferrin increased IL-6 and KC (CXCL1) in lung tissue. Increased numbers of macrophages were observed in TDM-injected mice given human or mouse lactoferrin. Granulomatous pathology, composed of mainly migrated leukocytes, was visually reduced in mice that received human or mouse lactoferrin. Quantitation of granulomatous pathology demonstrated a significant decrease in mice given human or mouse lactoferrin compared with TDM control mice. This report is the first to directly compare the immune modulatory effects of both heterologous recombinant human and homologous mouse lactoferrin on the development of TDM-induced granulomas.

Selective binding and transcytosis of Ulex europaeus 1 lectin by mouse Peyer's patch M-cells in vivo.

PubMed

Clark, M A; Jepson, M A; Simmons, N L; Hirst, B H

1995-12-01

The in vivo interaction of the lectin Ulex europaeus agglutinin 1 with mouse Peyer's patch follicle-associated epithelial cells was studied in the mouse Peyer's patch gut loop model by immunofluorescence and electron microscopy. The lectin targets to mouse Peyer's patch M-cells and is rapidly endocytosed and transcytosed. These processes are accompanied by morphological changes in the M-cell microvilli and by redistribution of polymerised actin. The demonstration of selective binding and uptake of a lectin by intestinal M-cells in vivo suggests that M-cell-specific surface glycoconjugates might act as receptors for the selective adhesion/uptake of microorganisms.

Acute uriticaria-like lesions in allergen-unexposed cutaneous tissues in a mouse model of late allergic rhinitis

PubMed Central

Hayashi, Toshiharu; Fujii, Taeko

2008-01-01

The mechanisms of distant manifestation after a local allergic reaction are largely unknown. This study examined the development of cutaneous lesions in a mouse model of late allergic rhinitis (LAR). BALB/c mice were sensitized by ovalbumin (OVA) intraperitoneally two times (on days 0 and 10) and challenged by OVA intranasally on day 14. Four days after OVA challenge, nasal and cutaneous lesions including helper T (Th) responses, expression of adhesion molecules and presence of OVA and IgE were examined, and compared with unsensitized and unchallenged (control) mice. Compared with the control group, the LAR group developed LAR characterized by infiltration of lymphocytes and eosinophils, increased IgE values and increased productions of IL-4 and IL-5, but not IFN-γ. A dominant infiltration of eosinophils and increase in mast cells, attachment of eosinophils to endothelium, intense expression of VCAM-1 on endothelium in venules and VLA-4 expression on eosinophils and mast cells were recognized in the cutaneous tissues. There were no differences in the expression of ICAM-1 on vascular endothelium and LFA-1 on infiltrated leucocytes between the two groups. CLA expression on lymphocytes was not detected, and the binding of OVA and IgE on mast cells and eosinophils was found in the cutaneous lesions in the LAR group, but not in the control group. This study suggests that acute uriticaria-like lesions in OVA-unexposed cutaneous tissues may be induced by immediate allergic reaction due to the systemic development of Th2-type response in a mouse model of LAR. PMID:18460071

Cytogenetic effects of sildenafil citrate (Viagra) on SWR/J mouse bone marrow cells.

PubMed

Abou-Tarboush, Faisal Mohamed; Abdel-Samad, Mohamed Fathy

2010-10-01

The present study was conducted to investigate the cytogenetic effects of sildenafil citrate in SWR/J mouse bone marrow cells. Thirty-six males and 36 females were used and divided into four groups. Each group contained 18 animals (9 males and 9 females), weighing 30-35 g. These animals were orally administered with a single dose of 13, 26 or 40 mg/kg sildenafil citrate solution. A control group received normal saline in an identical condition. The animals were sacrificed at 12, 24 or 48 h, after the treatment. Chromosome aberrations were investigated in 50 metaphases per animal. No significant differences in the percentages of mitotic indices or in the frequencies of chromosome aberrations were observed between treated male and female mice at any doses or at any time intervals used, therefore, data from the two sexes were pooled when analyzed statistically. No significant (p < 0.05) differences in the percentages of mitotic indices or in the frequencies of chromosome aberrations were observed between sildenafil citrate-treated groups and the control group at any doses or at any time intervals used. However, the percentages of centromeric adhesions increased significantly (p < 0.01) in treated groups as compared with the control group at all doses and at all time intervals used. In conclusion, the results of the present study suggest that sildenafil citrate does not have cytogenetic effects on mouse bone marrow cells, but the centromeric adhesions induced by this drug need further studies to confirm them and to investigate the possible mechanism(s) responsible for such effect.

Autophagy Constitutes a Protective Mechanism against Ethanol Toxicity in Mouse Astrocytes and Neurons.

PubMed

Pla, Antoni; Pascual, María; Guerri, Consuelo

2016-01-01

Ethanol induces brain damage and neurodegeneration by triggering inflammatory processes in glial cells through activation of Toll-like receptor 4 (TLR4) signaling. Recent evidence indicates the role of protein degradation pathways in neurodegeneration and alcoholic liver disease, but how these processes affect the brain remains elusive. We have demonstrated that chronic ethanol consumption impairs proteolytic pathways in mouse brain, and the immune response mediated by TLR4 receptors participates in these dysfunctions. We evaluate the in vitro effects of an acute ethanol dose on the autophagy-lysosome pathway (ALP) on WT and TLR4-/- mouse astrocytes and neurons in primary culture, and how these changes affect cell survival. Our results show that ethanol induces overexpression of several autophagy markers (ATG12, LC3-II, CTSB), and increases the number of lysosomes in WT astrocytes, effects accompanied by a basification of lysosomal pH and by lowered phosphorylation levels of autophagy inhibitor mTOR, along with activation of complexes beclin-1 and ULK1. Notably, we found only minor changes between control and ethanol-treated TLR4-/- mouse astroglial cells. Ethanol also triggers the expression of the inflammatory mediators iNOS and COX-2, but induces astroglial death only slightly. Blocking autophagy by using specific inhibitors increases both inflammation and cell death. Conversely, in neurons, ethanol down-regulates the autophagy pathway and triggers cell death, which is partially recovered by using autophagy enhancers. These results support the protective role of the ALP against ethanol-induced astroglial cell damage in a TLR4-dependent manner, and provide new insight into the mechanisms that underlie ethanol-induced brain damage and are neuronal sensitive to the ethanol effects.

Genetic tracing of the gustatory and trigeminal neural pathways originating from T1R3-expressing taste receptor cells and solitary chemoreceptor cells.

PubMed

Ohmoto, Makoto; Matsumoto, Ichiro; Yasuoka, Akihito; Yoshihara, Yoshihiro; Abe, Keiko

2008-08-01

We established transgenic mouse lines expressing a transneuronal tracer, wheat germ agglutinin (WGA), under the control of mouse T1R3 gene promoter/enhancer. In the taste buds, WGA transgene was faithfully expressed in T1R3-positive sweet/umami taste receptor cells. WGA protein was transferred not laterally to the synapse-bearing, sour-responsive type III cells in the taste buds but directly to a subset of neurons in the geniculate and nodose/petrosal ganglia, and further conveyed to a rostro-central region of the nucleus of solitary tract. In addition, WGA was expressed in solitary chemoreceptor cells in the nasal epithelium and transferred along the trigeminal sensory pathway to the brainstem neurons. The solitary chemoreceptor cells endogenously expressed T1R3 together with bitter taste receptors T2Rs. This result shows an exceptional signature of receptor expression. Thus, the t1r3-WGA transgenic mice revealed the sweet/umami gustatory pathways from taste receptor cells and the trigeminal neural pathway from solitary chemoreceptor cells.

Temporally and spatially controllable gene expression and knockout in mouse urothelium.

PubMed

Zhou, Haiping; Liu, Yan; He, Feng; Mo, Lan; Sun, Tung-Tien; Wu, Xue-Ru

2010-08-01

Urothelium that lines almost the entire urinary tract performs important functions and is prone to assaults by urinary microbials, metabolites, and carcinogens. To improve our understanding of urothelial physiology and disease pathogenesis, we sought to develop two novel transgenic systems, one that would allow inducible and urothelium-specific gene expression, and another that would allow inducible and urothelium-specific knockout. Toward this end, we combined the ability of the mouse uroplakin II promoter (mUPII) to drive urothelium-specific gene expression with a versatile tetracycline-mediated inducible system. We found that, when constructed under the control of mUPII, only a modified, reverse tetracycline trans-activator (rtTA-M2), but not its original version (rtTA), could efficiently trans-activate reporter gene expression in mouse urothelium on doxycycline (Dox) induction. The mUPII/rtTA-M2-inducible system retained its strict urothelial specificity, had no background activity in the absence of Dox, and responded rapidly to Dox administration. Using a reporter gene whose expression was secondarily controlled by histone remodeling, we were able to identify, colocalize with 5-bromo-2-deoxyuridine incorporation, and semiquantify newly divided urothelial cells. Finally, we established that, when combined with a Cre recombinase under the control of the tetracycline operon, the mUPII-driven rtTA-M2 could inducibly inactivate any gene of interest in mouse urothelium. The establishment of these two new transgenic mouse systems enables the manipulation of gene expression and/or inactivation in adult mouse urothelium at any given time, thus minimizing potential compensatory effects due to gene overexpression or loss and allowing more accurate modeling of urothelial diseases than previously reported constitutive systems.

FoxP2 protein levels regulate cell morphology changes and migration patterns in the vertebrate developing telencephalon.

PubMed

Garcia-Calero, Elena; Botella-Lopez, Arancha; Bahamonde, Olga; Perez-Balaguer, Ariadna; Martinez, Salvador

2016-07-01

In the mammalian telencephalon, part of the progenitor cells transition from multipolar to bipolar morphology as they invade the mantle zone. This associates with changing patterns of radial migration. However, the molecules implicated in these morphology transitions are not well known. In the present work, we analyzed the function of FoxP2 protein in this process during telencephalic development in vertebrates. We analyzed the expression of FoxP2 protein and its relation with cell morphology and migratory patterns in mouse and chicken developing striatum. We observed FoxP2 protein expressed in a gradient from the subventricular zone to the mantle layer in mice embryos. In the FoxP2 low domain cells showed multipolar migration. In the striatal mantle layer where FoxP2 protein expression is higher, cells showed locomoting migration and bipolar morphology. In contrast, FoxP2 showed a high and homogenous expression pattern in chicken striatum, thus bipolar morphology predominated. Elevation of FoxP2 in the striatal subventricular zone by in utero electroporation promoted bipolar morphology and impaired multipolar radial migration. In mouse cerebral cortex we obtained similar results. FoxP2 promotes transition from multipolar to bipolar morphology by means of gradiental expression in mouse striatum and cortex. Together these results indicate a role of FoxP2 differential expression in cell morphology control of the vertebrate telencephalon.

Inactivation of the F4/80 glycoprotein in the mouse germ line.

PubMed

Schaller, Evelyne; Macfarlane, Alison J; Rupec, Rudolf A; Gordon, Siamon; McKnight, Andrew J; Pfeffer, Klaus

2002-11-01

Macrophages play a crucial role in the defense against pathogens. Distinct macrophage populations can be defined by the expression of restricted cell surface proteins. Resident tissue macrophages, encompassing Kupffer cells of the liver and red pulp macrophages of the spleen, characteristically express the F4/80 molecule, a cell surface glycoprotein related to the seven transmembrane-spanning family of hormone receptors. In this study, gene targeting was used to simultaneously inactivate the F4/80 molecule in the germ line of the mouse and to produce a mouse line that expresses the Cre recombinase under the direct control of the F4/80 promoter (F4/80-Cre knock-in). F4/80-deficient mice are healthy and fertile. Macrophage populations in tissues can develop in the absence of F4/80 expression. Functional analysis revealed that the generation of T-cell-independent B-cell responses and macrophage antimicrobial defense after infection with Listeria monocytogenes are not impaired in the absence of F4/80. Interestingly, tissues of F4/80-deficient mice could not be labeled with anti-BM8, another macrophage subset-specific marker with hitherto undefined molecular antigenic structure. Recombinant expression of a F4/80 cDNA in heterologous cells confirmed this observation, indicating that the targets recognized by the F4/80 and BM8 monoclonal antibodies are identical.

Lentiviral vectors containing mouse Csf1r control elements direct macrophage-restricted expression in multiple species of birds and mammals

PubMed Central

Pridans, Clare; Lillico, Simon; Whitelaw, Bruce; Hume, David A

2014-01-01

The development of macrophages requires signaling through the lineage-restricted receptor Csf1r. Macrophage-restricted expression of transgenic reporters based upon Csf1r requires the highly conserved Fms-intronic regulatory element (FIRE). We have created a lentiviral construct containing mouse FIRE and promoter. The lentivirus is capable of directing macrophage-restricted reporter gene expression in mouse, rat, human, pig, cow, sheep, and even chicken. Rat bone marrow cells transduced with the lentivirus were capable of differentiating into macrophages expressing the reporter gene in vitro. Macrophage-restricted expression may be desirable for immunization or immune response modulation, and for gene therapy for lysosomal storage diseases and some immunodeficiencies. The small size of the Csf1r transcription control elements will allow the insertion of large “cargo” for applications in gene therapy and vaccine delivery. PMID:26015955

Calcium influences sensitivity to growth inhibition induced by a cell surface sialoglycopeptide

NASA Technical Reports Server (NTRS)

Betz, N. A.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

1994-01-01

While studies concerning mitogenic factors have been an important area of research for many years, much less is understood about the mechanisms of action of cell surface growth inhibitors. We have purified an 18 kDa cell surface sialoglycopeptide growth inhibitor (CeReS-18) which can reversibly inhibit the proliferation of diverse cell types. The studies discussed in this article show that three mouse keratinocyte cell lines exhibit sixty-fold greater sensitivity than other fibroblasts and epithelial-like cells to CeReS-18-induced growth inhibition. Growth inhibition induced by CeReS-18 treatment is a reversible process, and the three mouse keratinocyte cell lines exhibited either single or multiple cell cycle arrest points, although a predominantly G0/G1 cell cycle arrest point was exhibited in Swiss 3T3 fibroblasts. The sensitivity of the mouse keratinocyte cell lines to CeReS-18-induced growth inhibition was not affected by the degree of tumorigenic progression in the cell lines and was not due to differences in CeReS-18 binding affinity or number of cell surface receptors per cell. However, the sensitivity of both murine fibroblasts and keratinocytes could be altered by changing the extracellular calcium concentration, such that increased extracellular calcium concentrations resulted in decreased sensitivity to CeReS-18-induced proliferation inhibition. Thus the increased sensitivity of the murine keratinocyte cell lines to CeReS-18 could be ascribed to the low calcium concentration used in their propagation. Studies are currently under way investigating the role of calcium in CeReS-18-induced growth arrest. The CeReS-18 may serve as a very useful tool to study negative growth control and the signal transduction events associated with cell cycling.

P21 cip-Overexpression in the Mouse β Cells Leads to the Improved Recovery from Streptozotocin-Induced Diabetes

PubMed Central

Jiang, Wei; Sun, Xiaoning; Han, Yuhua; Ding, Mingxiao; Shi, Yan; Deng, Hongkui

2009-01-01

Under normal conditions, the regeneration of mouse β cells is mainly dependent on their own duplication. Although there is evidence that pancreatic progenitor cells exist around duct, whether non-β cells in the islet could also potentially contribute to β cell regeneration in vivo is still controversial. Here, we developed a novel transgenic mouse model to study the pancreatic β cell regeneration, which could specifically inhibit β cell proliferation by overexpressing p21 cip in β cells via regulation of the Tet-on system. We discovered that p21 overexpression could inhibit β-cell duplication in the transgenic mice and these mice would gradually suffer from hyperglycemia. Importantly, the recovery efficiency of the p21-overexpressing mice from streptozotocin-induced diabetes was significantly higher than control mice, which is embodied by better physiological quality and earlier emergence of insulin expressing cells. Furthermore, in the islets of these streptozotocin-treated transgenic mice, we found a large population of proliferating cells which expressed pancreatic duodenal homeobox 1 (PDX1) but not markers of terminally differentiated cells. Transcription factors characteristic of early pancreatic development, such as Nkx2.2 and NeuroD1, and pancreatic progenitor markers, such as Ngn3 and c-Met, could also be detected in these islets. Thus, our work showed for the first time that when β cell self-duplication is repressed by p21 overexpression, the markers for embryonic pancreatic progenitor cells could be detected in islets, which might contribute to the recovery of these transgenic mice from streptozotocin-induced diabetes. These discoveries could be important for exploring new diabetes therapies that directly promote the regeneration of pancreatic progenitors to differentiate into islet β cells in vivo. PMID:20020058

PEA and luteolin synergistically reduce mast cell-mediated toxicity and elicit neuroprotection in cell-based models of brain ischemia.

PubMed

Parrella, Edoardo; Porrini, Vanessa; Iorio, Rosa; Benarese, Marina; Lanzillotta, Annamaria; Mota, Mariana; Fusco, Mariella; Tonin, Paolo; Spano, PierFranco; Pizzi, Marina

2016-10-01

The combination of palmitoylethanolamide (PEA), an endogenous fatty acid amide belonging to the family of the N-acylethanolamines, and the flavonoid luteolin has been found to exert neuroprotective activities in a variety of mouse models of neurological disorders, including brain ischemia. Indirect findings suggest that the two molecules can reduce the activation of mastocytes in brain ischemia, thus modulating crucial cells that trigger the inflammatory cascade. Though, no evidence exists about a direct effect of PEA and luteolin on mast cells in experimental models of brain ischemia, either used separately or in combination. In order to fill this gap, we developed a novel cell-based model of severe brain ischemia consisting of primary mouse cortical neurons and cloned mast cells derived from mouse fetal liver (MC/9 cells) subjected to oxygen and glucose deprivation (OGD). OGD exposure promoted both mast cell degranulation and the release of lactate dehydrogenase (LDH) in a time-dependent fashion. MC/9 cells exacerbated neuronal damage in neuron-mast cells co-cultures exposed to OGD. Likewise, the conditioned medium derived from OGD-exposed MC/9 cells induced significant neurotoxicity in control primary neurons. PEA and luteolin pre-treatment synergistically prevented the OGD-induced degranulation of mast cells and reduced the neurotoxic potential of MC/9 cells conditioned medium. Finally, the association of the two drugs promoted a direct synergistic neuroprotection even in pure cortical neurons exposed to OGD. In summary, our results indicate that mast cells release neurotoxic factors upon OGD-induced activation. The association PEA-luteolin actively reduces mast cell-mediated neurotoxicity as well as pure neurons susceptibility to OGD. Copyright © 2016 Elsevier B.V. All rights reserved.

A Functional Analysis on the Interspecies Interaction between Mouse LFA-1 and Human Intercellular Adhesion Molecule-1 at the Cell Level

PubMed Central

Núñez, David; Comas, Laura; Lanuza, Pilar M.; Sánchez-Martinez, Diego; Pérez-Hernández, Marta; Catalán, Elena; Domingo, María Pilar; Velázquez-Campoy, Adrián; Pardo, Julián; Gálvez, Eva M.

2017-01-01

The interaction between intercellular adhesion molecules (ICAM) and the integrin leukocyte function-associated antigen-1 (LFA-1) is crucial for the regulation of several physiological and pathophysiological processes like cell-mediated elimination of tumor or virus infected cells, cancer metastasis, or inflammatory and autoimmune processes. Using purified proteins it was reported a species restriction for the interaction of ICAM-1 and LFA-1, being mouse ICAM-1 able to interact with human LFA-1 but not human ICAM-1 with mouse LFA-1. However, in vivo results employing tumor cells transfected with human ICAM-1 suggest that functionally mouse LFA-1 can recognize human ICAM-1. In order to clarify the interspecies cross-reactivity of the ICAM-1/LFA-1 interaction, we have performed functional studies analyzing the ability of human soluble ICAM-1 and human/mouse LFA-1 derived peptides to inhibit cell aggregation and adhesion as well as cell-mediated cytotoxicity in both mouse and human systems. In parallel, the affinity of the interaction between mouse LFA-1-derived peptides and human ICAM-1 was determined by calorimetry assays. According to the results obtained, it seems that human ICAM-1 is able to interact with mouse LFA-1 on intact cells, which should be taking into account when using humanized mice and xenograft models for the study of immune-related processes. PMID:29312326

A Functional Analysis on the Interspecies Interaction between Mouse LFA-1 and Human Intercellular Adhesion Molecule-1 at the Cell Level.

PubMed

Núñez, David; Comas, Laura; Lanuza, Pilar M; Sánchez-Martinez, Diego; Pérez-Hernández, Marta; Catalán, Elena; Domingo, María Pilar; Velázquez-Campoy, Adrián; Pardo, Julián; Gálvez, Eva M

2017-01-01

The interaction between intercellular adhesion molecules (ICAM) and the integrin leukocyte function-associated antigen-1 (LFA-1) is crucial for the regulation of several physiological and pathophysiological processes like cell-mediated elimination of tumor or virus infected cells, cancer metastasis, or inflammatory and autoimmune processes. Using purified proteins it was reported a species restriction for the interaction of ICAM-1 and LFA-1, being mouse ICAM-1 able to interact with human LFA-1 but not human ICAM-1 with mouse LFA-1. However, in vivo results employing tumor cells transfected with human ICAM-1 suggest that functionally mouse LFA-1 can recognize human ICAM-1. In order to clarify the interspecies cross-reactivity of the ICAM-1/LFA-1 interaction, we have performed functional studies analyzing the ability of human soluble ICAM-1 and human/mouse LFA-1 derived peptides to inhibit cell aggregation and adhesion as well as cell-mediated cytotoxicity in both mouse and human systems. In parallel, the affinity of the interaction between mouse LFA-1-derived peptides and human ICAM-1 was determined by calorimetry assays. According to the results obtained, it seems that human ICAM-1 is able to interact with mouse LFA-1 on intact cells, which should be taking into account when using humanized mice and xenograft models for the study of immune-related processes.

Overlapping and distinct pRb pathways in the mammalian auditory and vestibular organs

PubMed Central

Huang, Mingqian; Sage, Cyrille; Tang, Yong; Lee, Sang Goo; Petrillo, Marco; Hinds, Philip W

2011-01-01

Retinoblastoma gene (Rb1) is required for proper cell cycle exit in the developing mouse inner ear and its deletion in the embryo leads to proliferation of sensory progenitor cells that differentiate into hair cells and supporting cells. In a conditional hair cell Rb1 knockout mouse, Pou4f3-Cre-pRb™/™, pRb™/™ utricular hair cells differentiate and survive into adulthood whereas differentiation and survival of pRb™/™ cochlear hair cells are impaired. To comprehensively survey the pRb pathway in the mammalian inner ear, we performed microarray analysis of pRb™/™ cochlea and utricle. The comparative analysis shows that the core pathway shared between pRb™/™ cochlea and utricle is centered on e2F, the key pathway that mediates pRb function. A majority of differentially expressed genes and enriched pathways are not shared but uniquely associated with pRb™/™ cochlea or utricle. In pRb™/™ cochlea, pathways involved in early inner ear development such as Wnt/β-catenin and Notch were enriched, whereas pathways involved in proliferation and survival are enriched in pRb™/™ utricle. Clustering analysis showed that the pRb™/™ inner ear has characteristics of a younger control inner ear, an indication of delayed differentiation. We created a transgenic mouse model (ER-Cre-pRbflox/flox) in which Rb1 can be acutely deleted postnatally. Acute Rb1 deletion in the adult mouse fails to induce proliferation or cell death in inner ear, strongly indicating that Rb1 loss in these postmitotic tissues can be effectively compensated for, or that pRb-mediated changes in the postmitotic compartment result in events that are functionally irreversible once enacted. This study thus supports the concept that pRb-regulated pathways relevant to hair cell development, encompassing proliferation, differentiation and survival, act predominantly during early development. PMID:21239885

Urinary Peptides As a Novel Source of T Cell Allergen Epitopes

PubMed Central

da Silva Antunes, Ricardo; Pham, John; McMurtrey, Curtis; Hildebrand, William H.; Phillips, Elizabeth; Mallal, Simon; Sidney, John; Busse, Paula; Peters, Bjoern; Schulten, Véronique; Sette, Alessandro

2018-01-01

Mouse allergy in both laboratory workers and in inner-city children is associated with allergic rhinitis and asthma, posing a serious public health concern. Urine is a major source of mouse allergens, as mice spray urine onto their surroundings, where the proteins dry up and become airborne on dust particles. Here, we tested whether oligopeptides that are abundant in mouse urine may contribute to mouse allergic T cell response. Over 1,300 distinct oligopeptides were detected by mass spectrometry analysis of the low molecular weight filtrate fraction of mouse urine (LoMo). Posttranslationally modified peptides were common, accounting for almost half of total peptides. A pool consisting of 225 unique oligopeptides of 13 residues or more in size identified within was tested for its capacity to elicit T cell reactivity in mouse allergic donors. Following 14-day in vitro stimulation of PBMCs, we detected responses in about 95% of donors tested, directed against 116 distinct peptides, predominantly associated with Th2 cytokines (IL-5). Peptides from non-urine related proteins such as epidermal growth factor, collagen, and Beta-globin accounted for the highest response (15.9, 9.1, and 8.1% of the total response, respectively). Peptides derived from major urinary proteins (MUPs), kidney androgen-regulated protein (KAP), and uromodulin were the main T cell targets from kidney or urine related sources. Further ex vivo analysis of enrichment of 4-1BB expressing cells demonstrated that LoMo pool-specific T cell reactivity can be detected directly ex vivo in mouse allergic but not in non-allergic donors. Further cytometric analysis of responding cells revealed a bone fide memory T cell phenotype and confirmed their Th2 polarization. Overall, these data suggest that mouse urine-derived oligopeptides are a novel target for mouse allergy-associated T cell responses, which may contribute to immunopathological mechanisms in mouse allergy. PMID:29755469

T cell post-transcriptional miRNA-mRNA interaction networks identify targets associated with susceptibility/resistance to collagen-induced arthritis.

PubMed

Donate, Paula B; Fornari, Thais A; Macedo, Claudia; Cunha, Thiago M; Nascimento, Daniele C B; Sakamoto-Hojo, Elza T; Donadi, Eduardo A; Cunha, Fernando Q; Passos, Geraldo A

2013-01-01

Due to recent studies indicating that the deregulation of microRNAs (miRNAs) in T cells contributes to increased severity of rheumatoid arthritis, we hypothesized that deregulated miRNAs may interact with key mRNA targets controlling the function or differentiation of these cells in this disease. To test our hypothesis, we used microarrays to survey, for the first time, the expression of all known mouse miRNAs in parallel with genome-wide mRNAs in thymocytes and naïve and activated peripheral CD3(+) T cells from two mouse strains the DBA-1/J strain (MHC-H2q), which is susceptible to collagen induced arthritis (CIA), and the DBA-2/J strain (MHC-H2d), which is resistant. Hierarchical clustering of data showed the several T cell miRNAs and mRNAs differentially expressed between the mouse strains in different stages of immunization with collagen. Bayesian statistics using the GenMir(++) algorithm allowed reconstruction of post-transcriptional miRNA-mRNA interaction networks for target prediction. We revealed the participation of miR-500, miR-202-3p and miR-30b*, which established interactions with at least one of the following mRNAs: Rorc, Fas, Fasl, Il-10 and Foxo3. Among the interactions that were validated by calculating the minimal free-energy of base pairing between the miRNA and the 3'UTR of the mRNA target and luciferase assay, we highlight the interaction of miR-30b*-Rorc mRNA because the mRNA encodes a protein implicated in pro-inflammatory Th17 cell differentiation (Rorγt). FACS analysis revealed that Rorγt protein levels and Th17 cell counts were comparatively reduced in the DBA-2/J strain. This result showed that the miRNAs and mRNAs identified in this study represent new candidates regulating T cell function and controlling susceptibility and resistance to CIA.

Introduction of N-cadherin-binding motif to alginate hydrogels for controlled stem cell differentiation.

PubMed

Lee, Jae Won; An, Hyoseok; Lee, Kuen Yong

2017-07-01

Control of stem cell fate and phenotype using biomimetic synthetic extracellular matrices (ECMs) is an important tissue engineering approach. Many studies have focused on improving cell-matrix interactions. However, proper control of cell-cell interactions using synthetic ECMs could be critical for tissue engineering, especially with undifferentiated stem cells. In this study, alginate hydrogels were modified with a peptide derived from the low-density lipoprotein receptor-related protein 5 (LRP5), which is known to bind to N-cadherin, as a cell-cell interaction motif. In vitro changes in the morphology and differentiation of mouse bone marrow stromal cells (D1 stem cells) cultured in LRP5-alginate hydrogels were investigated. LRP5-alginate gels successfully induced stem cell aggregation and enhanced chondrogenic differentiation of D1 stem cells, compared to RGD-alginate gels, at low cell density. This approach to tailoring synthetic biomimetic ECMs using cell-cell interaction motifs may be critical in tissue engineering approaches using stem cells. Copyright © 2017 Elsevier B.V. All rights reserved.

A potential inhibitory function of draxin in regulating mouse trunk neural crest migration.

PubMed

Zhang, Sanbing; Su, Yuhong; Gao, Jinbao; Zhang, Chenbing; Tanaka, Hideaki

2017-01-01

Draxin is a repulsive axon guidance protein that plays important roles in the formation of three commissures in the central nervous system and dorsal interneuron 3 (dI3) in the chick spinal cord. In the present study, we report the expression pattern of mouse draxin in the embryonic mouse trunk spinal cord. In the presence of draxin, the longest net migration length of a migrating mouse trunk neural crest cell was significantly reduced. In addition, the relative number of apolar neural crest cells increased as the draxin treatment time increased. Draxin caused actin cytoskeleton rearrangement in the migrating trunk neural crest cells. Our data suggest that draxin may regulate mouse trunk neural crest cell migration by the rearrangement of cell actin cytoskeleton and by reducing the polarization activity of these cells subsequently.

Immunohistochemical localization of translationally controlled tumor protein in the mouse digestive system.

PubMed

Sheverdin, Vadim; Jung, Jiwon; Lee, Kyunglim

2013-09-01

Translationally controlled tumor protein (TCTP) is a housekeeping protein, highly conserved among various species. It plays a major role in cell differentiation, growth, proliferation, apoptosis and carcinogenesis. Studies reported so far on TCTP expression in different digestive organs have not led to any understanding of the role of TCTP in digestion, so we localized TCTP in organs of the mouse digestive system employing immunohistochemical techniques. Translationally controlled tumor protein was found expressed in all organs studied: tongue, salivary glands, esophagus, stomach, small and large intestines, liver and pancreas. The expression of TCTP was found to be predominant in epithelia and neurons of myenteric nerve ganglia; high in serous glands (parotid, submandibular, gastric, intestinal crypts, pancreatic acini) and in neurons of myenteric nerve ganglia, and moderate to low in epithelia. In epithelia, expression of TCTP varied depending on its type and location. In enteric neurons, TCTP was predominantly expressed in the processes. Translationally controlled tumor protein expression in the liver followed porto-central gradient with higher expression in pericentral hepatocytes. In the pancreas, TCTP was expressed in both acini and islet cells. Our finding of nearly universal localization and expression of TCTP in mouse digestive organs points to the hitherto unrecognized functional importance of TCTP in the digestive system and suggests the need for further studies of the possible role of TCTP in the proliferation, secretion, absorption and neural regulation of the digestive process and its importance in the physiology and pathology of digestive process. © 2013 Anatomical Society.

Immunohistochemical localization of translationally controlled tumor protein in the mouse digestive system

PubMed Central

Sheverdin, Vadim; Jung, Jiwon; Lee, Kyunglim

2013-01-01

Translationally controlled tumor protein (TCTP) is a housekeeping protein, highly conserved among various species. It plays a major role in cell differentiation, growth, proliferation, apoptosis and carcinogenesis. Studies reported so far on TCTP expression in different digestive organs have not led to any understanding of the role of TCTP in digestion, so we localized TCTP in organs of the mouse digestive system employing immunohistochemical techniques. Translationally controlled tumor protein was found expressed in all organs studied: tongue, salivary glands, esophagus, stomach, small and large intestines, liver and pancreas. The expression of TCTP was found to be predominant in epithelia and neurons of myenteric nerve ganglia; high in serous glands (parotid, submandibular, gastric, intestinal crypts, pancreatic acini) and in neurons of myenteric nerve ganglia, and moderate to low in epithelia. In epithelia, expression of TCTP varied depending on its type and location. In enteric neurons, TCTP was predominantly expressed in the processes. Translationally controlled tumor protein expression in the liver followed porto-central gradient with higher expression in pericentral hepatocytes. In the pancreas, TCTP was expressed in both acini and islet cells. Our finding of nearly universal localization and expression of TCTP in mouse digestive organs points to the hitherto unrecognized functional importance of TCTP in the digestive system and suggests the need for further studies of the possible role of TCTP in the proliferation, secretion, absorption and neural regulation of the digestive process and its importance in the physiology and pathology of digestive process. PMID:23834399

Lentivirus-mediated shRNA interference of ghrelin receptor blocks proliferation in the colorectal cancer cells.

PubMed

Liu, An; Huang, Chenggang; Xu, Jia; Cai, Xuehong

2016-09-01

Ghrelin, an orexigenic peptide, acts via the growth hormone secretagogue receptor (GHSR) to stimulate the release of growth hormone. Moreover, it has a range of biological actions, including the stimulation of food intake, modulation of insulin signaling and cardiovascular effects. Recently, it has been demonstrated that ghrelin has a proliferative and antiapoptotic effects in cancers, suggesting a potential role in promoting tumor growth. However, it remains unknown whether GHSR contributes to colorectal cancer proliferation. In this study, the therapeutic effect of lentivirus-mediated short hairpin RNA (shRNA) targeting ghrelin receptor 1a (GHSR1a) was analyzed in colorectal cancer cell line SW480 both in vitro and in vivo. Our study demonstrated that ghrelin and GHSR1a are significantly upregulated in cancerous colorectal tissue samples and cell lines. In vitro, human colorectal cancer cell line SW480 with downregulation of GHSR1a by shRNA showed significant inhibition of cell viability compared with blank control (BC) or scrambled control (SC) regardless of the application of exogenous ghrelin. Furthermore, GHSR1a silencing by target specific shRNA was shown capable of increasing PTEN, inhibiting AKT phosphorylation and promoting the release of p53 in SW480 cells. In addition, the effects of GHSR1a knockdown were further explored in vivo using colorectal tumor xenograft mouse model. The tumor weights were decreased markedly in GHSR1α knockdown SW480 mouse xenograft tumors compared with blank control or negative control tumors. Our results suggested that the expression of GHSR1a is significantly correlated with the growth of colorectal cancer cells, and the GHSR1a knockdown approach may be a potential therapy for the treatment of colorectal cancer. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Rheologic and hemodynamic characteristics of red cells of mouse, rat and human.

PubMed

Chen, D; Kaul, D K

1994-01-01

The present study compares hematologic, rheologic and hemodynamic characteristics of red cells from mouse, rat and human. Red cells in these species are biconcave discs that show significant differences in diameter and mean corpuscular volume (MCV). However, differences in mean corpuscular hemoglobin concentration (MCHC) are not significant. Viscosity measurement of washed red cell suspensions (in each case the medium osmolarity adjusted to match plasma osmolarity) showed significant interspecies differences at shear rates of 37.5 and 750 sec-1 as follows: Human > rat > mouse. Hemodynamic and microcirculatory behavior of these red cells was investigated in the artificially perfused ex vivo mesocecum vasculature of the rat. Hemodynamic measurements in the whole ex vivo mesocecum preparation revealed maximal increase in the peripheral resistance unit (PRU) for the human red cells followed by the rat and mouse red cells, respectively at a hematocrit (Hct) of 40%. Further, measurements of red cell velocities (Vrbc) in single arterioles of the mesocecum vasculature, during sustained perfusion with washed red cell suspensions, showed that at any given perfusion pressure (Pa), Vrbc for both mouse and rat red cells was higher than that for human red cells, while Vrbc for mouse red cells was higher than that for the rat. These results demonstrate that the microvascular flow behavior of these red cells is likely to be influenced by both physical and rheologic characteristics.

Elimination of mouse tumor cells from neonate spermatogonial cells utilizing cisplatin-entrapped folic acid-conjugated poly(lactic-co-glycolic acid) nanoparticles in vitro.

PubMed

Shabani, Ronak; Ashjari, Mohsen; Ashtari, Khadijeh; Izadyar, Fariborz; Behnam, Babak; Khoei, Samideh; Asghari-Jafarabadi, Mohamad; Koruji, Morteza

2018-01-01

Some male survivors of childhood cancer are suffering from azoospermia. In addition, spermatogonial stem cells (SSCs) are necessary for the improvement of spermatogenesis subsequent to exposure to cytotoxic agents such as cisplatin. The aim of this study was to evaluate the anticancer activity of cisplatin-loaded folic acid-conjugated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) on mouse malignant cell line (EL4) and SSCs in vitro. SSCs were co-cultured with mouse malignant cell line (EL4) cells and divided into four culture groups: 1) control (cells were co-cultured in the culture medium), 2) co-cultured cells were treated with cisplatin (10 μg/mL), 3) co-cultured cells were treated with cisplatin-loaded folic acid-conjugated PLGA NPs, and 4) co-cultures were treated with folic acid-conjugated PLGA for 48 hours. The NPs were prepared, characterized, and targeted with folate. In vitro release characteristics, loading efficiency, and scanning electron microscopy and transmission electron microscopy images were studied. Cancer cells were assayed after treatment using flow cytometry and TUNEL assay. The co-cultures of SSCs and EL4 cells were injected into seminiferous tubules of the testes after treating with cis-diaminedichloroplatinum/PLGA NPs. The mean diameter of PLGA NPs ranged between 150 and 250 nm. The number of TUNEL-positive cells increased, and the expression of Bax and caspase-3 were upregulated in EL4 cells in Group 4 compared with Group 2. There was no pathological tumor in testes after transplantation with treated co-cultured cells. The PLGA NPs appeared to act as a promising carrier for cisplatin administration, which was consistent with a higher activation of apoptosis than free drug.

Elimination of mouse tumor cells from neonate spermatogonial cells utilizing cisplatin-entrapped folic acid-conjugated poly(lactic-co-glycolic acid) nanoparticles in vitro

PubMed Central

Shabani, Ronak; Ashjari, Mohsen; Ashtari, Khadijeh; Izadyar, Fariborz; Behnam, Babak; Khoei, Samideh; Asghari-Jafarabadi, Mohamad; Koruji, Morteza

2018-01-01

Background Some male survivors of childhood cancer are suffering from azoospermia. In addition, spermatogonial stem cells (SSCs) are necessary for the improvement of spermatogenesis subsequent to exposure to cytotoxic agents such as cisplatin. Objective The aim of this study was to evaluate the anticancer activity of cisplatin-loaded folic acid-conjugated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) on mouse malignant cell line (EL4) and SSCs in vitro. Methods SSCs were co-cultured with mouse malignant cell line (EL4) cells and divided into four culture groups: 1) control (cells were co-cultured in the culture medium), 2) co-cultured cells were treated with cisplatin (10 μg/mL), 3) co-cultured cells were treated with cisplatin-loaded folic acid-conjugated PLGA NPs, and 4) co-cultures were treated with folic acid-conjugated PLGA for 48 hours. The NPs were prepared, characterized, and targeted with folate. In vitro release characteristics, loading efficiency, and scanning electron microscopy and transmission electron microscopy images were studied. Cancer cells were assayed after treatment using flow cytometry and TUNEL assay. The co-cultures of SSCs and EL4 cells were injected into seminiferous tubules of the testes after treating with cis-diaminedichloroplatinum/PLGA NPs. Results The mean diameter of PLGA NPs ranged between 150 and 250 nm. The number of TUNEL-positive cells increased, and the expression of Bax and caspase-3 were upregulated in EL4 cells in Group 4 compared with Group 2. There was no pathological tumor in testes after transplantation with treated co-cultured cells. Conclusion The PLGA NPs appeared to act as a promising carrier for cisplatin administration, which was consistent with a higher activation of apoptosis than free drug. PMID:29849458

Chemical coding and chemosensory properties of cholinergic brush cells in the mouse gastrointestinal and biliary tract.

PubMed

Schütz, Burkhard; Jurastow, Innokentij; Bader, Sandra; Ringer, Cornelia; von Engelhardt, Jakob; Chubanov, Vladimir; Gudermann, Thomas; Diener, Martin; Kummer, Wolfgang; Krasteva-Christ, Gabriela; Weihe, Eberhard

2015-01-01

The mouse gastro-intestinal and biliary tract mucosal epithelia harbor choline acetyltransferase (ChAT)-positive brush cells with taste cell-like traits. With the aid of two transgenic mouse lines that express green fluorescent protein (EGFP) under the control of the ChAT promoter (EGFP (ChAT) ) and by using in situ hybridization and immunohistochemistry we found that EGFP (ChAT) cells were clustered in the epithelium lining the gastric groove. EGFP (ChAT) cells were numerous in the gall bladder and bile duct, and found scattered as solitary cells along the small and large intestine. While all EGFP (ChAT) cells were also ChAT-positive, expression of the high-affinity choline transporter (ChT1) was never detected. Except for the proximal colon, EGFP (ChAT) cells also lacked detectable expression of the vesicular acetylcholine transporter (VAChT). EGFP (ChAT) cells were found to be separate from enteroendocrine cells, however they were all immunoreactive for cytokeratin 18 (CK18), transient receptor potential melastatin-like subtype 5 channel (TRPM5), and for cyclooxygenases 1 (COX1) and 2 (COX2). The ex vivo stimulation of colonic EGFP (ChAT) cells with the bitter substance denatonium resulted in a strong increase in intracellular calcium, while in other epithelial cells such an increase was significantly weaker and also timely delayed. Subsequent stimulation with cycloheximide was ineffective in both cell populations. Given their chemical coding and chemosensory properties, EGFP (ChAT) brush cells thus may have integrative functions and participate in induction of protective reflexes and inflammatory events by utilizing ACh and prostaglandins for paracrine signaling.

In vitro chronotropic effects of Erythrina senegalensis DC (Fabaceae) aqueous extract on mouse heart slice and pluripotent stem cell-derived cardiomyocytes.

PubMed

Nembo, Erastus Nembu; Atsamo, Albert Donatien; Nguelefack, Télesphore Benoît; Kamanyi, Albert; Hescheler, Jürgen; Nguemo, Filomain

2015-05-13

Erythrina senegalensis DC (Fabaceae) bark is commonly used in sub-Saharan traditional medicine for the treatment of many diseases including gastrointestinal disorders and cardiovascular diseases. In this study, we investigated the effect of the aqueous extract of the stem bark of Erythrina senegalensis on the contractile properties of mouse ventricular slices and human induced pluripotent stem (hiPS) cell-derived cardiomyocytes. We also investigated the cytotoxic effect of the extract on mouse embryonic stem (ES) cells differentiating into cardiomyocytes (CMs). We used well-established electrophysiological technologies to assess the effect of Erythrina senegalensis aqueous extract (ESAE) on the beating activity of mouse ventricular slices, mouse ES and hiPS cell-derived CMs. To study the cytotoxic effect of our extract, differentiating mouse ES cells were exposed to different concentrations of ESAE. EB morphology was assessed by microscopy at different stages of differentiation whereas cell viability was measured by flow cytometry, fluorometry and immunocytochemistry. The electrical activity of CMs and heart slices were respectively captured by the patch clamp technique and microelectrode array (MEA) method following ESAE acute exposure. Our findings revealed that ESAE exhibits a biphasic chronotropic activity on mouse ventricular slices with an initial low dose (0.001 and 0.01 µg/mL) decrease in beating activity followed by a corresponding significant increase in chronotropic activity at higher doses above 10 µg/mL. The muscarinic receptor blocker, atropine abolished the negative chronotropic activity of ESAE, while propranolol successfully blocked its positive chronotropic activity. ESAE showed a significant dose-dependent positive chronotropic activity on hiPS cell-derived CMs. Also, though not significantly, ESAE decreased cell viability and increased total caspase-3/7 activity of mouse ES cells in a concentration-dependent manner. Erythrina senegalensis aqueous extract exhibits a biphasic chronotropic effect on mouse heart and a positive chronotropic activity on hiPS cell-derived CMs, suggesting a possible mechanism through muscarinic and β-adrenergic receptor pathways. Also, ESAE is not cytotoxic on mouse ES cells at concentrations up to 100 µg/mL. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Suppressive effects of a novel CC chemokine receptor 4 antagonist on Th2 cell trafficking in ligand- and antigen-induced mouse models.

PubMed

Komiya, Takaki; Sugiyama, Tetsuya; Takeda, Kazuhiko; Watanabe, Noriki; Imai, Masamichi; Kokubo, Masaya; Tokuda, Natsuko; Ochiai, Hiroshi; Habashita, Hiromu; Shibayama, Shiro

2013-11-15

CC chemokine receptor 4 (CCR4) has been implicated as a preferential marker for T helper type 2 (Th2) cells, and is believed to be involved in the pathology of allergic diseases by controlling Th2 cell trafficking into inflamed tissues. The objective of the study was to characterize the pharmacological properties of E0001-163, a novel CCR4 antagonist. E0001-163 was tested in both in vitro chemotaxis assays as well as in vivo mouse models of CCR4 ligand-induced air pouch and antigen-induced airway inflammation by utilizing in vitro-polarized Th2 cells. In vitro, E0001-163 inhibited migratory response of human Th2-polarized cells to CCL22, a CCR4 ligand, with an IC50 value of 11.9 nM. E0001-163 significantly suppressed CCL22-induced Th2 cell trafficking into mouse air pouch in a dose-dependent manner at doses of 3 and 10mg/kg, suggesting that E0001-163 has an inhibitory effect on CCR4-mediated T cell trafficking in vivo. In addition, E0001-163 partially decreased Th2 cell trafficking and the level of IL-4 in the lungs in Th2-tansferred and ovalbumin (OVA)-challenged mice. T cell trafficking involves multiple chemokine receptors both in acute and chronic phases, and our findings suggest that CCR4, together with other chemokine receptors, may be involved in Th2 cell trafficking under disease conditions. © 2013 Elsevier B.V. All rights reserved.

Restrictions in Cell Cycle Progression of Adult Vestibular Supporting Cells in Response to Ectopic Cyclin D1 Expression

PubMed Central

Loponen, Heidi; Ylikoski, Jukka; Albrecht, Jeffrey H.; Pirvola, Ulla

2011-01-01

Sensory hair cells and supporting cells of the mammalian inner ear are quiescent cells, which do not regenerate. In contrast, non-mammalian supporting cells have the ability to re-enter the cell cycle and produce replacement hair cells. Earlier studies have demonstrated cyclin D1 expression in the developing mouse supporting cells and its downregulation along maturation. In explant cultures of the mouse utricle, we have here focused on the cell cycle control mechanisms and proliferative potential of adult supporting cells. These cells were forced into the cell cycle through adenoviral-mediated cyclin D1 overexpression. Ectopic cyclin D1 triggered robust cell cycle re-entry of supporting cells, accompanied by changes in p27Kip1 and p21Cip1 expressions. Main part of cell cycle reactivated supporting cells were DNA damaged and arrested at the G2/M boundary. Only small numbers of mitotic supporting cells and rare cells with signs of two successive replications were found. Ectopic cyclin D1-triggered cell cycle reactivation did not lead to hyperplasia of the sensory epithelium. In addition, a part of ectopic cyclin D1 was sequestered in the cytoplasm, reflecting its ineffective nuclear import. Combined, our data reveal intrinsic barriers that limit proliferative capacity of utricular supporting cells. PMID:22073316

Restrictions in cell cycle progression of adult vestibular supporting cells in response to ectopic cyclin D1 expression.

PubMed

Loponen, Heidi; Ylikoski, Jukka; Albrecht, Jeffrey H; Pirvola, Ulla

2011-01-01

Sensory hair cells and supporting cells of the mammalian inner ear are quiescent cells, which do not regenerate. In contrast, non-mammalian supporting cells have the ability to re-enter the cell cycle and produce replacement hair cells. Earlier studies have demonstrated cyclin D1 expression in the developing mouse supporting cells and its downregulation along maturation. In explant cultures of the mouse utricle, we have here focused on the cell cycle control mechanisms and proliferative potential of adult supporting cells. These cells were forced into the cell cycle through adenoviral-mediated cyclin D1 overexpression. Ectopic cyclin D1 triggered robust cell cycle re-entry of supporting cells, accompanied by changes in p27(Kip1) and p21(Cip1) expressions. Main part of cell cycle reactivated supporting cells were DNA damaged and arrested at the G2/M boundary. Only small numbers of mitotic supporting cells and rare cells with signs of two successive replications were found. Ectopic cyclin D1-triggered cell cycle reactivation did not lead to hyperplasia of the sensory epithelium. In addition, a part of ectopic cyclin D1 was sequestered in the cytoplasm, reflecting its ineffective nuclear import. Combined, our data reveal intrinsic barriers that limit proliferative capacity of utricular supporting cells.

Immunological tolerance as a barrier to protective HIV humoral immunity.

PubMed

Schroeder, Kristin Ms; Agazio, Amanda; Torres, Raul M

2017-08-01

HIV-1 infection typically eludes antibody control by our immune system and is not yet prevented by a vaccine. While many viral features contribute to this immune evasion, broadly neutralizing antibodies (bnAbs) against HIV-1 are often autoreactive and it has been suggested that immunological tolerance may restrict a neutralizing antibody response. Indeed, recent Ig knockin mouse studies have shown that bnAb-expressing B cells are largely censored by central tolerance in the bone marrow. However, the contribution of peripheral tolerance in limiting the HIV antibody response by anergic and potentially protective B cells is poorly understood. Studies using mouse models to elucidate how anergic B cells are regulated and can be recruited into HIV-specific neutralizing antibody responses may provide insight into the development of a protective HIV-1 vaccine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lysosome acidification by photoactivated nanoparticles restores autophagy under lipotoxicity.

PubMed

Trudeau, Kyle M; Colby, Aaron H; Zeng, Jialiu; Las, Guy; Feng, Jiazuo H; Grinstaff, Mark W; Shirihai, Orian S

2016-07-04

In pancreatic β-cells, liver hepatocytes, and cardiomyocytes, chronic exposure to high levels of fatty acids (lipotoxicity) inhibits autophagic flux and concomitantly decreases lysosomal acidity. Whether impaired lysosomal acidification is causally inhibiting autophagic flux and cellular functions could not, up to the present, be determined because of the lack of an approach to modify lysosomal acidity. To address this question, lysosome-localizing nanoparticles are described that, upon UV photoactivation, enable controlled acidification of impaired lysosomes. The photoactivatable, acidifying nanoparticles (paNPs) demonstrate lysosomal uptake in INS1 and mouse β-cells. Photoactivation of paNPs in fatty acid-treated INS1 cells enhances lysosomal acidity and function while decreasing p62 and LC3-II levels, indicating rescue of autophagic flux upon acute lysosomal acidification. Furthermore, paNPs improve glucose-stimulated insulin secretion that is reduced under lipotoxicity in INS1 cells and mouse islets. These results establish a causative role for impaired lysosomal acidification in the deregulation of autophagy and β-cell function under lipotoxicity. © 2016 Trudeau et al.

A common haplotype lowers PU.1 expression in myeloid cells and delays onset of Alzheimer's disease.

PubMed

Huang, Kuan-Lin; Marcora, Edoardo; Pimenova, Anna A; Di Narzo, Antonio F; Kapoor, Manav; Jin, Sheng Chih; Harari, Oscar; Bertelsen, Sarah; Fairfax, Benjamin P; Czajkowski, Jake; Chouraki, Vincent; Grenier-Boley, Benjamin; Bellenguez, Céline; Deming, Yuetiva; McKenzie, Andrew; Raj, Towfique; Renton, Alan E; Budde, John; Smith, Albert; Fitzpatrick, Annette; Bis, Joshua C; DeStefano, Anita; Adams, Hieab H H; Ikram, M Arfan; van der Lee, Sven; Del-Aguila, Jorge L; Fernandez, Maria Victoria; Ibañez, Laura; Sims, Rebecca; Escott-Price, Valentina; Mayeux, Richard; Haines, Jonathan L; Farrer, Lindsay A; Pericak-Vance, Margaret A; Lambert, Jean Charles; van Duijn, Cornelia; Launer, Lenore; Seshadri, Sudha; Williams, Julie; Amouyel, Philippe; Schellenberg, Gerard D; Zhang, Bin; Borecki, Ingrid; Kauwe, John S K; Cruchaga, Carlos; Hao, Ke; Goate, Alison M

2017-08-01

A genome-wide survival analysis of 14,406 Alzheimer's disease (AD) cases and 25,849 controls identified eight previously reported AD risk loci and 14 novel loci associated with age at onset. Linkage disequilibrium score regression of 220 cell types implicated the regulation of myeloid gene expression in AD risk. The minor allele of rs1057233 (G), within the previously reported CELF1 AD risk locus, showed association with delayed AD onset and lower expression of SPI1 in monocytes and macrophages. SPI1 encodes PU.1, a transcription factor critical for myeloid cell development and function. AD heritability was enriched within the PU.1 cistrome, implicating a myeloid PU.1 target gene network in AD. Finally, experimentally altered PU.1 levels affected the expression of mouse orthologs of many AD risk genes and the phagocytic activity of mouse microglial cells. Our results suggest that lower SPI1 expression reduces AD risk by regulating myeloid gene expression and cell function.

PI3 K/Akt/mTOR-mediated translational control regulates proliferation and differentiation of lineage-restricted RoSH stem cell lines

PubMed Central

Que, Jianwen; Lian, Qizhou; El Oakley, Reida M; Lim, Bing; Lim, Sai-Kiang

2007-01-01

Background We have previously derived highly similar lineage-restricted stem cell lines, RoSH and E-RoSH cell lines from mouse embryos and CD9hi SSEA-1- differentiated mouse embryonic stem cells, respectively. These cell lines are not pluripotent and differentiate readily into endothelial cells in vitro and in vivo. Results We investigated the signaling pathway that maintains proliferation of these cells in an undifferentiated state, and demonstrate that PI3 K/Akt/mTOR, but not Raf/MEK/Erk, signaling in these cells was active during proliferation and was downregulated during endothelial differentiation. Inhibition of PI3 K/Akt/mTOR signaling, but not Raf/MEK/Erk, reduced proliferation and induced expression of endothelial specific proteins. During differentiation or inhibition of PI3 K/Akt/mTOR signaling, cyclinD2 transcript abundance in ribosome-enriched RNA but not in total RNA was reduced with a corresponding reduction in protein level. In contrast, transcript abundance of endothelial-specific genes e.g. Kdr, Tek and Pdgfrα in ribosome-enriched RNA fraction was not reduced and their protein levels were increased. Together these observations suggested that translational control mediated by PI3K/Akt/mTOR signaling was critical in regulating proliferation and endothelial differentiation of lineage-restricted RoSH-like stem cell lines. Conclusion This study highlights translation regulation as a critical regulatory mechanism during proliferation and differentiation in stem cells. PMID:17892597

Further Insights into the Ciliary Gene and Protein KIZ and Its Murine Ortholog PLK1S1 Mutated in Rod-Cone Dystrophy

PubMed Central

Méjécase, Cécile; Bertelli, Matteo; Terray, Angélique; Michiels, Christelle; Condroyer, Christel; Fouquet, Stéphane; Sadoun, Maxime; Clérin, Emmanuelle; Liu, Binqian; Léveillard, Thierry; Goureau, Olivier; Sahel, José-Alain; Audo, Isabelle

2017-01-01

We identified herein additional patients with rod-cone dystrophy (RCD) displaying mutations in KIZ, encoding the ciliary centrosomal protein kizuna and performed functional characterization of the respective protein in human fibroblasts and of its mouse ortholog PLK1S1 in the retina. Mutation screening was done by targeted next generation sequencing and subsequent Sanger sequencing validation. KIZ mRNA levels were assessed on blood and serum-deprived human fibroblasts from a control individual and a patient, compound heterozygous for the c.52G>T (p.Glu18*) and c.119_122del (p.Lys40Ilefs*14) mutations in KIZ. KIZ localization, documentation of cilium length and immunoblotting were performed in these two fibroblast cell lines. In addition, PLK1S1 immunolocalization was conducted in mouse retinal cryosections and isolated rod photoreceptors. Analyses of additional RCD patients enabled the identification of two homozygous mutations in KIZ, the known c.226C>T (p.Arg76*) mutation and a novel variant, the c.3G>A (p.Met1?) mutation. Albeit the expression levels of KIZ were three-times lower in the patient than controls in whole blood cells, further analyses in control- and mutant KIZ patient-derived fibroblasts unexpectedly revealed no significant difference between the two genotypes. Furthermore, the averaged monocilia length in the two fibroblast cell lines was similar, consistent with the preserved immunolocalization of KIZ at the basal body of the primary cilia. Analyses in mouse retina and isolated rod photoreceptors showed PLK1S1 localization at the base of the photoreceptor connecting cilium. In conclusion, two additional patients with mutations in KIZ were identified, further supporting that defects in KIZ/PLK1S1, detected at the basal body of the primary cilia in fibroblasts, and the photoreceptor connecting cilium in mouse, respectively, are involved in RCD. However, albeit the mutations were predicted to lead to nonsense mediated mRNA decay, we could not detect changes upon expression levels, protein localization or cilia length in KIZ-mutated fibroblast cells. Together, our findings unveil the limitations of fibroblasts as a cellular model for RCD and call for other models such as induced pluripotent stem cells to shed light on retinal pathogenic mechanisms of KIZ mutations. PMID:29057815

Two Pore Channel 2 Differentially Modulates Neural Differentiation of Mouse Embryonic Stem Cells

PubMed Central

Zhang, Zhe-Hao; Lu, Ying-Ying; Yue, Jianbo

2013-01-01

Nicotinic acid adenine dinucleotide phosphate (NAADP) is an endogenous Ca2+ mobilizing nucleotide presented in various species. NAADP mobilizes Ca2+ from acidic organelles through two pore channel 2 (TPC2) in many cell types and it has been previously shown that NAADP can potently induce neuronal differentiation in PC12 cells. Here we examined the role of TPC2 signaling in the neural differentiation of mouse embryonic stem (ES) cells. We found that the expression of TPC2 was markedly decreased during the initial ES cell entry into neural progenitors, and the levels of TPC2 gradually rebounded during the late stages of neurogenesis. Correspondingly, TPC2 knockdown accelerated mouse ES cell differentiation into neural progenitors but inhibited these neural progenitors from committing to neurons. Overexpression of TPC2, on the other hand, inhibited mouse ES cell from entering the early neural lineage. Interestingly, TPC2 knockdown had no effect on the differentiation of astrocytes and oligodendrocytes of mouse ES cells. Taken together, our data indicate that TPC2 signaling plays a temporal and differential role in modulating the neural lineage entry of mouse ES cells, in that TPC2 signaling inhibits ES cell entry to early neural progenitors, but is required for late neuronal differentiation. PMID:23776607

Magnetic field activated lipid-polymer hybrid nanoparticles for stimuli-responsive drug release.

PubMed

Kong, Seong Deok; Sartor, Marta; Hu, Che-Ming Jack; Zhang, Weizhou; Zhang, Liangfang; Jin, Sungho

2013-03-01

Stimuli-responsive nanoparticles (SRNPs) offer the potential of enhancing the therapeutic efficacy and minimizing the side-effects of chemotherapeutics by controllably releasing the encapsulated drug at the target site. Currently controlled drug release through external activation remains a major challenge during the delivery of therapeutic agents. Here we report a lipid-polymer hybrid nanoparticle system containing magnetic beads for stimuli-responsive drug release using a remote radio frequency (RF) magnetic field. These hybrid nanoparticles show long-term stability in terms of particle size and polydispersity index in phosphate-buffered saline (PBS). Controllable loading of camptothecin (CPT) and Fe(3)O(4) in the hybrid nanoparticles was demonstrated. RF-controlled drug release from these nanoparticles was observed. In addition, cellular uptake of the SRNPs into MT2 mouse breast cancer cells was examined. Using CPT as a model anticancer drug the nanoparticles showed a significant reduction in MT2 mouse breast cancer cell growth in vitro in the presence of a remote RF field. The ease of preparation, stability, and controllable drug release are the strengths of the platform and provide the opportunity to improve cancer chemotherapy. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Mouse strain and injection site are crucial for detecting linked suppression in transplant recipients by trans-vivo DTH assay.

PubMed

Burlingham, W J; Jankowska-Gan, E

2007-02-01

Chemokine-driven accumulation of lymphocytes, mononuclear and polymorphonuclear proinflammatory cells in antigenic tissue sites is a key feature of several types of T-cell-dependent autoimmunity and transplant rejection pathology. It is now clear that the immune system expends considerable energy to control this process, exemplified by the sequential layers of regulatory cell input, both innate and adaptive, designed to prevent a classical Type IV or 'delayed-type' hypersensitivity (DTH) reaction from occurring in the visual field of the eye. Yet, despite an abundance of in vitro assays currently available to the human T-cell immunologist, none of them adequately models the human DTH response and its various control features. The theme of this article is that it is relatively easy to model the effector side of the human DTH response with xenogeneic adoptive transfer models. However, we show that in order to detect inhibition of a recall DTH in response to colocalized donor antigen (linked suppression)--a characteristic feature of peripheral tolerance to an organ transplant--both the challenge site and the immunocompetence of the mouse adoptive host are critical factors limiting the sensitivity of the trans-vivo DTH test.

Development and function of human innate immune cells in a humanized mouse model.

PubMed

Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V; Teichmann, Lino L; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A Karolina; Manz, Markus G; Flavell, Richard A

2014-04-01

Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models cannot support development of human innate immune cells, including myeloid cells and natural killer (NK) cells. Here we describe two mouse strains called MITRG and MISTRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked into their respective mouse loci. The human cytokines support the development and function of monocytes, macrophages and NK cells derived from human fetal liver or adult CD34(+) progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MITRG and MISTRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology.

Development and function of human innate immune cells in a humanized mouse model

PubMed Central

Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V.; Teichmann, Lino L.; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A. Karolina; Manz, Markus G.; Flavell, Richard A.

2014-01-01

Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models are unable to support development of human innate immune cells, including myeloid cells and NK cells. Here we describe a mouse strain, called MI(S)TRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked in to their respective mouse loci. The human cytokines support the development and function of monocytes/macrophages and natural killer cells derived from human fetal liver or adult CD34+ progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MI(S)TRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology. PMID:24633240

Rho kinase inhibitor Y-27632 and Accutase dramatically increase mouse embryonic stem cell derivation.

PubMed

Zhang, Peng; Wu, Xinglong; Hu, Chunchao; Wang, Pengbo; Li, Xiangyun

2012-01-01

Although it has been 30 yr since the development of derivation methods for mouse embryonic stem (ES) cells, the biology of derivation of ES cells is poorly understood and the efficiency varies dramatically between cell lines. Recently, the Rho kinase inhibitor Y-27632 and the cell dissociation reagent Accutase were reported to significantly inhibit apoptosis of human ES cells during passaging. Therefore, in the current study, C57BL/6×129/Sv mouse blastocysts were used to evaluate the effect of the combination of the two reagents instead of using the conventional 129 line in mouse ES cell derivation. The data presented in this study suggests that the combination of Y-27632 and Accutase significantly increases the efficiency of mouse ES cell derivation; furthermore, no negative side effects were observed with Y-27632 and Accutase treatment. The newly established ES cell lines retain stable karyotype, surface markers expression, formed teratomas, and contributed to viable chimeras and germline transmission by tetraploid complementation assay. In addition, Y-27632 improved embryoid body formation of ES cells. During ES cell microinjection, Y-27632 prevented the formation of dissociation-induced cell blebs and facilitates the selection and the capture of intact cells. The methods presented in this study clearly demonstrate that inhibition of Rho kinase with Y-27632 and Accutase dissociation improve the derivation efficiently and reproducibility of mouse ES cell generation which is essential for reducing variability in the results obtained from different cell lines.

Bio-engineering inslulin-secreting cells from embryonic stem cells: a review of progress.

PubMed

Roche, E; Sepulcre, M P; Enseñat-Waser, R; Maestre, I; Reig, J A; Soria, B

2003-07-01

According to the Edmonton protocol, human islet transplantation can result in insulin independency for periods longer than 3 years. However, this therapy for type 1 diabetes is limited by the scarcity of cadaveric donors. Owing to the ability of embryonic stem cells to expand in vitro and differentiate into a variety of cell types, research has focused on ways to manipulate these cells to overcome this problem. It has been demonstrated that mouse embryonic stem cells can differentiate into insulin-containing cells, restoring normoglycaemia in diabetic mice. To this end, mouse embryonic stem cells were transfected with a DNA construct that provides resistance to neomycin under the control of the regulatory regions of the human insulin gene. However, this protocol has a very low efficiency, needing improvements for this technology to be transferred to human stem cells. Optimum protocols will be instrumental in the production of an unlimited source of cells that synthesise, store and release insulin in a physiological manner. The review focuses on the alternative source of tissue offered by embryonic stem cells for regenerative medicine in diabetes and some key points that should be considered in order for a definitive protocol for in vitro differentiation to be established.

[An experimental study of mesenchymal stem cells in tissue engineering scaffolds implanted in rabbit corneal lamellae to increase keratoprosthesis biointegration].

PubMed

Bai, H; Wang, L L; Huang, Y F; Huang, J X

2016-03-01

To complete a preliminary evaluation of the feasibility of implanting the complex of mouse bone marrow mesenchymal stem cells (BMSC) and a tissue engineering scaffold into rabbit corneal lamellae, based on which a solution may be proposed to consolidate the keratoprosthesis and the recipient surface, and to reduce the risk of complications. This experimental study was composed of two parts. (1) In vitro: some mouse BMSC were marked with red fluorescent proteins (RFP) and integrated with a decellularized pig articular cartilage extracellular matrix (ECM) scaffold. The cell survival was observed under a fluorescence microscope at 4 and 8 weeks. The cell distribution was examined by toluidine blue staining. The pore structure and the cell adhesion were observed under a scanning electron microscope. (2) in vivo: the complex of mouse BMSC and a decellularized scaffold was implanted into the lamellar cornea of 8 rabbit eyes with the fellow eyes as the controls. The eyes were sampled for observation using HE staining under a light microscope at 2, 4 and 8 weeks, respectively. The cell survival was examined under a fluorescence microscope, and the intracorneal cell survival at 8 weeks was observed using in vivo imaging. The conditions of ocular anterior segment of all the experimental animals were recorded. (1) Under the scanning electron microscope, the ECM scaffolds showed satisfactory porosity required for the adhesion and growth of cells and tissues, and the cell distribution over the cell-scaffold complex can be observed by toluidine blue staining. (2) Under the immunofluorescence microscope, cell proliferation was observed in vitro and in the interlamellar space (the maximum observation time was 8 weeks) after the RFP-marked mouse BMSC were integrated in vitro with ECM scaffolds. (3) Under the light microscope (HE staining), the stromal cells were detected to increase at each timepoint. A small number of monocytes and some mouse BMSC were observed in the superficial layer of corneal stroma, with sparsely and orderly arranged collagenous fibers and no neovascularization. All the epithelial cells appeared as mononuclear, columnar and undamaged, and the shape of ECM scaffolds, which were fused with the collagens, became unclear. (4) By in vivo imaging, it was found that the mouse BMSC survived for 8 weeks after being integrated with scaffolds and implanted into the interlamellar space of rabbit cornea. (5) After the implantation of cell-scaffold complex, severe postoperative inflammatory reactions, obvious conjunctival congestion and neovascularization were not observed. The corneal tissues surrounding the recipient area were transparent. One week later, mild inflammatory reactions were barely observed, and the cornea was transparent enough to observe the scaffold in the stromal layers. Four weeks later, the scaffolds became thinner. Eight weeks later, the scaffolds became extremely thin with normal vascular system in the corneal limbus. The ECM scaffold is a solid and biocompatible carrier for the growth and proliferation of BMSC. The mouse BMSC can grow and proliferate in the microenvironment of the interlamellar space of cornea.

Smooth muscle cell-specific knockout of androgen receptor: a new model for prostatic disease.

PubMed

Welsh, Michelle; Moffat, Lindsey; McNeilly, Alan; Brownstein, David; Saunders, Philippa T K; Sharpe, Richard M; Smith, Lee B

2011-09-01

Androgen-driven stromal-epithelial interactions play a key role in normal prostate development and function as well as in the progression of common prostatic diseases such as benign prostatic hyperplasia and prostate cancer. However, exactly how, and via which cell type, androgens mediate their effects in the adult prostate remains unclear. This study investigated the role for smooth muscle (SM) androgen signaling in normal adult prostate homeostasis and function using mice in which androgen receptor was selectively ablated from prostatic SM cells. In adulthood the knockout (KO) mice displayed a 44% reduction in prostate weight and exhibited histological abnormalities such as hyperplasia, inflammation, fibrosis, and reduced expression of epithelial, SM, and stem cell identify markers (e.g. p63 reduced by 27% and Pten by 31%). These changes emerged beyond puberty and were not explained by changes in serum hormones. Furthermore, in response to exogenous estradiol, adult KO mice displayed an 8.5-fold greater increase in prostate weight than controls and developed urinary retention. KO mice also demonstrated a reduced response to castration compared with controls. Together these results demonstrate that prostate SM cells are vital in mediating androgen-driven stromal-epithelial interactions in adult mouse prostates, determining cell identity and function and limiting hormone-dependent epithelial cell proliferation. This novel mouse model provides new insight into the possible role for SM androgen action in prostate disease.

Deciphering the Mechanism of Alternative Cleavage and Polyadenylation in Mantle Cell Lymphoma (MCL)

DTIC Science & Technology

2015-12-01

expression, increased cell proliferation and increased tumor growth in an in vivo mouse xenograft . [13]. However, Pcf11 did not have any effect on the...miRNA Regulation through Alternative Polyadenylation in Glioblastoma . (Selected for Plenary talk). Symposia on Cancer research, 2014. Illuminating...Albrecht T.R., Li W., Shyu A-B., and Wagner, E.J. CFlm25 Links Global change in APA to Cell Growth Control and Glioblastoma Survival. Abstract

A Knock-in Mouse Model of Human PHD2 Gene-associated Erythrocytosis Establishes a Haploinsufficiency Mechanism*

PubMed Central

Arsenault, Patrick R.; Pei, Fei; Lee, Rebecca; Kerestes, Heddy; Percy, Melanie J.; Keith, Brian; Simon, M. Celeste; Lappin, Terence R. J.; Khurana, Tejvir S.; Lee, Frank S.

2013-01-01

The central pathway for controlling red cell mass is the PHD (prolyl hydroxylase domain protein):hypoxia-inducible factor (HIF) pathway. HIF, which is negatively regulated by PHD, activates numerous genes, including ones involved in erythropoiesis, such as the ERYTHROPOIETIN (EPO) gene. Recent studies have implicated PHD2 as the key PHD isoform regulating red cell mass. Studies of humans have identified erythrocytosis-associated, heterozygous point mutations in the PHD2 gene. A key question concerns the mechanism by which human mutations lead to phenotypes. In the present report, we generated and characterized a mouse line in which a P294R knock-in mutation has been introduced into the mouse Phd2 locus to model the first reported human PHD2 mutation (P317R). Phd2P294R/+ mice display a degree of erythrocytosis equivalent to that seen in Phd2+/− mice. The Phd2P294R/+-associated erythrocytosis is reversed in a Hif2a+/−, but not a Hif1a+/− background. Additional studies using various conditional knock-outs of Phd2 reveal that erythrocytosis can be induced by homozygous and heterozygous knock-out of Phd2 in renal cortical interstitial cells using a Pax3-Cre transgene or by homozygous knock-out of Phd2 in hematopoietic progenitors driven by a Vav1-Cre transgene. These studies formally prove that a missense mutation in PHD2 is the cause of the erythrocytosis, show that this occurs through haploinsufficiency, and point to multifactorial control of red cell mass by PHD2. PMID:24121508

SerpinB1 Promotes Pancreatic β Cell Proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

El Ouaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas

2016-01-01

Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuatedmore » β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.« less

The Distributions of Voltage-Gated K+ current Subtypes in Different Cell Sizes from Adult Mouse Dorsal Root Ganglia.

PubMed

Sheng, Anqi; Hong, Jiangru; Zhang, Lulu; Zhang, Yan; Zhang, Guangqin

2018-03-29

Voltage-gated K + (K V ) currents play a crucial role in regulating pain by controlling neuronal excitability, and are divided into transient A-type currents (I A ) and delayed rectifier currents (I K ). The dorsal root ganglion (DRG) neurons are heterogeneous and the subtypes of K V currents display different levels in distinct cell sizes. To observe correlations of the subtypes of K V currents with DRG cell sizes, K V currents were recorded by whole-cell patch clamp in freshly isolated mouse DRG neurons. Results showed that I A occupied a high proportion in K V currents in medium- and large-diameter DRG neurons, whereas I K possessed a larger proportion of K V currents in small-diameter DRG neurons. A lower correlation was found between the proportion of I A or I K in K V currents and cell sizes. These data suggest that I A channels are mainly expressed in medium and large cells and I K channels are predominantly expressed in small cells.

Cellular Specificity of the Blood–CSF Barrier for Albumin Transfer across the Choroid Plexus Epithelium

PubMed Central

Liddelow, Shane A.; Dzięgielewska, Katarzyna M.; Møllgård, Kjeld; Whish, Sophie C.; Noor, Natassya M.; Wheaton, Benjamin J.; Gehwolf, Renate; Wagner, Andrea; Traweger, Andreas; Bauer, Hannelore; Bauer, Hans-Christian; Saunders, Norman R.

2014-01-01

To maintain the precise internal milieu of the mammalian central nervous system, well-controlled transfer of molecules from periphery into brain is required. Recently the soluble and cell-surface albumin-binding glycoprotein SPARC (secreted protein acidic and rich in cysteine) has been implicated in albumin transport into developing brain, however the exact mechanism remains unknown. We postulate that SPARC is a docking site for albumin, mediating its uptake and transfer by choroid plexus epithelial cells from blood into cerebrospinal fluid (CSF). We used in vivo physiological measurements of transfer of endogenous (mouse) and exogenous (human) albumins, in situ Proximity Ligation Assay (in situ PLA), and qRT-PCR experiments to examine the cellular mechanism mediating protein transfer across the blood–CSF interface. We report that at all developmental stages mouse albumin and SPARC gave positive signals with in situ PLAs in plasma, CSF and within individual plexus cells suggesting a possible molecular interaction. In contrast, in situ PLA experiments in brain sections from mice injected with human albumin showed positive signals for human albumin in the vascular compartment that were only rarely identifiable within choroid plexus cells and only at older ages. Concentrations of both endogenous mouse albumin and exogenous (intraperitoneally injected) human albumin were estimated in plasma and CSF and expressed as CSF/plasma concentration ratios. Human albumin was not transferred through the mouse blood–CSF barrier to the same extent as endogenous mouse albumin, confirming results from in situ PLA. During postnatal development Sparc gene expression was higher in early postnatal ages than in the adult and changed in response to altered levels of albumin in blood plasma in a differential and developmentally regulated manner. Here we propose a possible cellular route and mechanism by which albumin is transferred from blood into CSF across a sub-population of specialised choroid plexus epithelial cells. PMID:25211495

Adrenergic Signaling: A Targetable Checkpoint Limiting Development of the Antitumor Immune Response.

PubMed

Qiao, Guanxi; Chen, Minhui; Bucsek, Mark J; Repasky, Elizabeth A; Hylander, Bonnie L

2018-01-01

An immune response must be tightly controlled so that it will be commensurate with the level of response needed to protect the organism without damaging normal tissue. The roles of cytokines and chemokines in orchestrating these processes are well known, but although stress has long been thought to also affect immune responses, the underlying mechanisms were not as well understood. Recently, the role of nerves and, specifically, the sympathetic nervous system, in regulating immune responses is being revealed. Generally, an acute stress response is beneficial but chronic stress is detrimental because it suppresses the activities of effector immune cells while increasing the activities of immunosuppressive cells. In this review, we first discuss the underlying biology of adrenergic signaling in cells of both the innate and adaptive immune system. We then focus on the effects of chronic adrenergic stress in promoting tumor growth, giving examples of effects on tumor cells and immune cells, explaining the methods commonly used to induce stress in preclinical mouse models. We highlight how this relates to our observations that mandated housing conditions impose baseline chronic stress on mouse models, which is sufficient to cause chronic immunosuppression. This problem is not commonly recognized, but it has been shown to impact conclusions of several studies of mouse physiology and mouse models of disease. Moreover, the fact that preclinical mouse models are chronically immunosuppressed has critical ramifications for analysis of any experiments with an immune component. Our group has found that reducing adrenergic stress by housing mice at thermoneutrality or treating mice housed at cooler temperatures with β-blockers reverses immunosuppression and significantly improves responses to checkpoint inhibitor immunotherapy. These observations are clinically relevant because there are numerous retrospective epidemiological studies concluding that cancer patients who were taking β-blockers have better outcomes. Clinical trials testing whether β-blockers can be repurposed to improve the efficacy of traditional and immunotherapies in patients are on the horizon.

Adrenergic Signaling: A Targetable Checkpoint Limiting Development of the Antitumor Immune Response

PubMed Central

Qiao, Guanxi; Chen, Minhui; Bucsek, Mark J.; Repasky, Elizabeth A.; Hylander, Bonnie L.

2018-01-01

An immune response must be tightly controlled so that it will be commensurate with the level of response needed to protect the organism without damaging normal tissue. The roles of cytokines and chemokines in orchestrating these processes are well known, but although stress has long been thought to also affect immune responses, the underlying mechanisms were not as well understood. Recently, the role of nerves and, specifically, the sympathetic nervous system, in regulating immune responses is being revealed. Generally, an acute stress response is beneficial but chronic stress is detrimental because it suppresses the activities of effector immune cells while increasing the activities of immunosuppressive cells. In this review, we first discuss the underlying biology of adrenergic signaling in cells of both the innate and adaptive immune system. We then focus on the effects of chronic adrenergic stress in promoting tumor growth, giving examples of effects on tumor cells and immune cells, explaining the methods commonly used to induce stress in preclinical mouse models. We highlight how this relates to our observations that mandated housing conditions impose baseline chronic stress on mouse models, which is sufficient to cause chronic immunosuppression. This problem is not commonly recognized, but it has been shown to impact conclusions of several studies of mouse physiology and mouse models of disease. Moreover, the fact that preclinical mouse models are chronically immunosuppressed has critical ramifications for analysis of any experiments with an immune component. Our group has found that reducing adrenergic stress by housing mice at thermoneutrality or treating mice housed at cooler temperatures with β-blockers reverses immunosuppression and significantly improves responses to checkpoint inhibitor immunotherapy. These observations are clinically relevant because there are numerous retrospective epidemiological studies concluding that cancer patients who were taking β-blockers have better outcomes. Clinical trials testing whether β-blockers can be repurposed to improve the efficacy of traditional and immunotherapies in patients are on the horizon. PMID:29479349

Molecular Determinants of Antiestrogen and Drug Sensitivity in Breast Carcinoma Cells

DTIC Science & Technology

1997-08-01

W.S. human HT1080 fibrosarcoma cells (a gift of Pear, personal communication). G.R. Stark), susceptible to ecotropic retrovirus In several...transfection with equal amounts of plasmid pOPRSVIluc (generated by replacing CAT of pORRSVICAT with luc) which expresses luc from R02 promoter, and control...retroviral transduction into (Fig. 1). During transient co-transfection of NIH 3T3 human HT1080 fibrosarcoma or mouse NIH 3T3 cell cells with a laac expressing

Mouse mammary tumor virus chromatin in human breast cancer cells is constitutively hypersensitive and exhibits steroid hormone-independent loading of transcription factors in vivo.

PubMed Central

Mymryk, J S; Berard, D; Hager, G L; Archer, T K

1995-01-01

We have stably introduced a reporter gene under the control of the mouse mammary tumor virus (MMTV) long terminal repeat (LTR) into human T47D breast cancer cells to study the action of the progesterone receptor (PR) on transcription from a chromatin template. Unexpectedly, the chromatin organization of the MMTV LTR in these human breast cancer cells differed markedly from what we have observed previously. The region adjacent to the transcription start site (-221 to -75) was found to be constitutively hypersensitive to restriction enzyme cleavage in the absence of hormone. This region is normally encompassed within the second nucleosome of a phased array of six nucleosomes that is assembled when the MMTV LTR is stably maintained in mouse cells. Characteristically, in these rodent cells, the identical DNA sequences show increased restriction enzyme cleavage only in the presence of glucocorticoid. The increased access of restriction enzymes observed in the human PR+ cells was not observed in adjacent nucleosomes and was unaffected by treatment with the progesterone antagonist RU486. In addition, exonuclease III-dependent stops corresponding to the binding sites for nuclear factor 1 and the PR were observed before and after hormone treatment. These results indicate that MMTV chromatin replicated in these cells is organized into a constitutively open architecture and that this open chromatin state is accompanied by hormone-independent loading of a transcription factor complex that is normally excluded from uninduced chromatin. PMID:7799933

Mouse mammary tumor virus chromatin in human breast cancer cells is constitutively hypersensitive and exhibits steroid hormone-independent loading of transcription factors in vivo.

PubMed

Mymryk, J S; Berard, D; Hager, G L; Archer, T K

1995-01-01

We have stably introduced a reporter gene under the control of the mouse mammary tumor virus (MMTV) long terminal repeat (LTR) into human T47D breast cancer cells to study the action of the progesterone receptor (PR) on transcription from a chromatin template. Unexpectedly, the chromatin organization of the MMTV LTR in these human breast cancer cells differed markedly from what we have observed previously. The region adjacent to the transcription start site (-221 to -75) was found to be constitutively hypersensitive to restriction enzyme cleavage in the absence of hormone. This region is normally encompassed within the second nucleosome of a phased array of six nucleosomes that is assembled when the MMTV LTR is stably maintained in mouse cells. Characteristically, in these rodent cells, the identical DNA sequences show increased restriction enzyme cleavage only in the presence of glucocorticoid. The increased access of restriction enzymes observed in the human PR+ cells was not observed in adjacent nucleosomes and was unaffected by treatment with the progesterone antagonist RU486. In addition, exonuclease III-dependent stops corresponding to the binding sites for nuclear factor 1 and the PR were observed before and after hormone treatment. These results indicate that MMTV chromatin replicated in these cells is organized into a constitutively open architecture and that this open chromatin state is accompanied by hormone-independent loading of a transcription factor complex that is normally excluded from uninduced chromatin.

[Effect of topical application of a recombinant adenovirus carrying promyelocytic leukemia gene in a psoriasis-like mouse model].

PubMed

Wang, Qiongyu; Zhang, Aijun; Ma, Huiqun; Wang, Shijie; Ma, Yunyun; Zou, Xingwei; Li, Ruilian

2013-03-01

To investigate the effects of topical treatment with adenovirus-mediated promyelocytic leukemia gene (PML) gene in a psoriasis-like mouse model. The effect of adenovirus-mediated PML gene on the granular layer of mouse tail scale epidermis and epithelial mitosis were observed on longitudinal histological sections prepared from the tail skin and vaginal epithelium of the mice. Adenovirus-mediated PML gene significantly inhibited mitosis of mouse vaginal epithelial cells and promoted the formation of granular layer in mouse tail scale epidermis. The therapeutic effect of PML gene in the psoriasis-like mouse model may be associated with increased granular cells and suppressed epidemic cell proliferation.

Epithelial V-Like Antigen Mediates Efficacy of Anti-Alpha4 Integrin Treatment in a Mouse Model of Multiple Sclerosis

PubMed Central

Wright, Erik; Rahgozar, Kusha; Hallworth, Nicholas; Lanker, Stefan; Carrithers, Michael D.

2013-01-01

Natalizumab inhibits the transmigration of activated T lymphocytes into the brain and is highly efficacious in multiple sclerosis (MS). However, from a pharmacogenomic perspective, its efficacy and safety in specific patients remain unclear. Here our goal was to analyze the effects of epithelial V-like antigen (EVA) on anti-alpha4 integrin (VLA4) efficacy in a mouse model of MS, experimental autoimmune encephalomyelitis (EAE). EVA has been previously characterized in human CD4 T lymphocytes, mouse thymic development, and choroid plexus epithelial cells. Further analysis here demonstrated expression in B lymphocytes and an increase in EVA+ lymphocytes following immunization. Following active induction of EAE using the MOG35–55 active immunization model, EVA deficient mice developed more severe EAE and white matter tissue injury as compared to wild type controls. This severe EAE phenotype did not respond to anti-VLA4 treatment. In both the control antibody and anti-VLA4 conditions, these mice demonstrated persistent CNS invasion of mature B lymphocyte (CD19+, CD21+, sIgG+), increased serum autoantibody levels, and extensive complement and IgG deposition within lesions containing CD5+IgG+ cells. Wild type mice treated with control antibody also demonstrated the presence of CD19+, CD21+, sIgG+ cells within the CNS during peak EAE disease severity and detectable serum autoantibody. In contrast, wild type mice treated with anti-VLA4 demonstrated reduced serum autoantibody levels as compared to wild type controls and EVA-knockout mice. As expected, anti-VLA4 treatment in wild type mice reduced the total numbers of all CNS mononuclear cells and markedly decreased CD4 T lymphocyte invasion. Treatment also reduced the frequency of CD19+, CD21+, sIgG+ cells in the CNS. These results suggest that anti-VLA4 treatment may reduce B lymphocyte associated autoimmunity in some individuals and that EVA expression is necessary for an optimal therapeutic response. We postulate that these findings could optimize the selection of treatment responders. PMID:23951051

Molecular cloning of a human Ca2+-dependent cell-cell adhesion molecule homologous to mouse placental cadherin: its low expression in human placental tissues

PubMed Central

1989-01-01

P-cadherin is a subclass of Ca2+-dependent cell-cell adhesion molecules present in mouse placenta, where its localization suggests a function of connecting the embryo to the uterus (Nose, A., and M. Takeichi. 1986. J. Cell Biol. 103:2649-2658). We recently identified a human cadherin detected by an mAb capable of disrupting cell-cell adhesion of A-431 cells, and found that it was closely related immunochemically to mouse P-cadherin. Curiously, this cadherin was undetectable in human placenta by immunohistochemical examination (Shimoyama, Y., S. Hirohashi, S. Hirano, M. Noguchi, Y. Shimosato, M. Takeichi, and O. Abe. 1989. Cancer Res. 49:2128-2133). We here report the cloning and sequencing of cDNA clone encoding the human homologue of mouse P- cadherin. The deduced amino acid sequence of the human P-cadherin consists of 829 amino acid and shows striking homology with mouse P- cadherin. On Northern blot analysis, human P-cadherin was scarcely expressed in human placenta in contrast to mouse P-cadherin, which was abundantly expressed in mouse placenta throughout pregnancy, and it was shown that E-cadherin, but not P-cadherin, was the major cadherin molecule in human placenta. Moreover, NIH3T3 cells transfected with human P-cadherin cDNA expressed the functional cadherin molecule, which was identical to the cadherin we had previously identified using the mAb, showing that this molecule really does mediate cell-cell adhesion and that the cadherin we detected immunochemically is undoubtedly human P-cadherin. The results obtained in this study support the idea that P- cadherin plays little role, if any, in Ca2+-dependent cell-cell binding in human placental tissue at least after several weeks of pregnancy. PMID:2793940

Hyperoxia reduces insulin release and induces mitochondrial dysfunction with possible implications for hyperoxic treatment of neonates.

PubMed

Hals, Ingrid; Ohki, Tsuyoshi; Singh, Rinku; Ma, Zuheng; Björklund, Anneli; Balasuriya, Chandima; Scholz, Hanne; Grill, Valdemar

2017-10-01

We previously showed that hyperoxia in vitro negatively affects beta cells of the rat. Here, we tested for possible clinical significance as well as mitochondrial interactions by hyperoxia, using human islets (function and viability), INS-1 832/13 cells (mitochondrial metabolism), and mouse neonates (effects in vivo). Lastly, we assessed relevant parameters in a cohort of individuals born preterm and then exposed to hyperoxia. Human islets and INS-1 832/13 cells were exposed to 24 h of hyperoxia (90-92% oxygen). Mouse neonates were subjected to 5 days of continuous hyperoxia. Individuals born preterm were evaluated in terms of glucose homeostasis and beta cell function by HbA1c and the HOMA2 formula. In human islets, hyperoxia significantly reduced glucose-stimulated insulin secretion by 42.2 ± 5.3% and viability assessed by MTT by 22.5 ± 5.4%. Hyperoxia down-regulated mitochondrial complex II by 21 ± 5% and upregulated complex III by 26 ± 10.1% and complex IV by 37 ± 10.6%. Partly similar effects on mitochondrial complexes were found in hyperoxia-exposed INS-1 832/13 cells. Exposure to hyperoxia swiftly reduced oxygen consumption in these cells and increased mitochondrial uncoupling. Hyperoxia transiently but significantly reduced insulin release in mouse neonates. Individuals born preterm displayed higher HbA1c versus controls, as well as insulin resistance. Thus, hyperoxia exerts negative effects in vitro on human beta cells and results indicate inhibitory effects on insulin secretion in vivo in mouse neonates. Negative effects may be lessened by the demonstrated swift and profound mitochondrial adaptability. Our findings open the possibility that hyperoxia could negatively affect beta cells of preterm human neonates. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

CRISPR/Cas9-mediated reversibly immortalized mouse bone marrow stromal stem cells (BMSCs) retain multipotent features of mesenchymal stem cells (MSCs).

PubMed

Hu, Xue; Li, Li; Yu, Xinyi; Zhang, Ruyi; Yan, Shujuan; Zeng, Zongyue; Shu, Yi; Zhao, Chen; Wu, Xingye; Lei, Jiayan; Li, Yasha; Zhang, Wenwen; Yang, Chao; Wu, Ke; Wu, Ying; An, Liping; Huang, Shifeng; Ji, Xiaojuan; Gong, Cheng; Yuan, Chengfu; Zhang, Linghuan; Liu, Wei; Huang, Bo; Feng, Yixiao; Zhang, Bo; Haydon, Rex C; Luu, Hue H; Reid, Russell R; Lee, Michael J; Wolf, Jennifer Moriatis; Yu, Zebo; He, Tong-Chuan

2017-12-19

Mesenchymal stem cells (MSCs) are multipotent non-hematopoietic progenitor cells that can undergo self-renewal and differentiate into multi-lineages. Bone marrow stromal stem cells (BMSCs) represent one of the most commonly-used MSCs. In order to overcome the technical challenge of maintaining primary BMSCs in long-term culture, here we seek to establish reversibly immortalized mouse BMSCs (imBMSCs). By exploiting CRISPR/Cas9-based homology-directed-repair (HDR) mechanism, we target SV40T to mouse Rosa26 locus and efficiently immortalize mouse BMSCs (i.e., imBMSCs). We also immortalize BMSCs with retroviral vector SSR #41 and establish imBMSC41 as a control line. Both imBMSCs and imBMSC41 exhibit long-term proliferative capability although imBMSC41 cells have a higher proliferation rate. SV40T mRNA expression is 130% higher in imBMSC41 than that in imBMSCs. However, FLP expression leads to 86% reduction of SV40T expression in imBMSCs, compared with 63% in imBMSC41 cells. Quantitative genomic PCR analysis indicates that the average copy number of SV40T and hygromycin is 1.05 for imBMSCs and 2.07 for imBMSC41, respectively. Moreover, FLP expression removes 92% of SV40T in imBMSCs at the genome DNA level, compared with 58% of that in imBMSC41 cells, indicating CRISPR/Cas9 HDR-mediated immortalization of BMSCs can be more effectively reversed than that of retrovirus-mediated random integrations. Nonetheless, both imBMSCs and imBMSC41 lines express MSC markers and are highly responsive to BMP9-induced osteogenic, chondrogenic and adipogenic differentiation in vitro and in vivo . Thus, the engineered imBMSCs can be used as a promising alternative source of primary MSCs for basic and translational research in the fields of MSC biology and regenerative medicine.

CRISPR/Cas9-mediated reversibly immortalized mouse bone marrow stromal stem cells (BMSCs) retain multipotent features of mesenchymal stem cells (MSCs)

PubMed Central

Hu, Xue; Li, Li; Yu, Xinyi; Zhang, Ruyi; Yan, Shujuan; Zeng, Zongyue; Shu, Yi; Zhao, Chen; Wu, Xingye; Lei, Jiayan; Li, Yasha; Zhang, Wenwen; Yang, Chao; Wu, Ke; Wu, Ying; An, Liping; Huang, Shifeng; Ji, Xiaojuan; Gong, Cheng; Yuan, Chengfu; Zhang, Linghuan; Liu, Wei; Huang, Bo; Feng, Yixiao; Zhang, Bo; Haydon, Rex C.; Luu, Hue H.; Reid, Russell R.; Lee, Michael J.; Wolf, Jennifer Moriatis; Yu, Zebo; He, Tong-Chuan

2017-01-01

Mesenchymal stem cells (MSCs) are multipotent non-hematopoietic progenitor cells that can undergo self-renewal and differentiate into multi-lineages. Bone marrow stromal stem cells (BMSCs) represent one of the most commonly-used MSCs. In order to overcome the technical challenge of maintaining primary BMSCs in long-term culture, here we seek to establish reversibly immortalized mouse BMSCs (imBMSCs). By exploiting CRISPR/Cas9-based homology-directed-repair (HDR) mechanism, we target SV40T to mouse Rosa26 locus and efficiently immortalize mouse BMSCs (i.e., imBMSCs). We also immortalize BMSCs with retroviral vector SSR #41 and establish imBMSC41 as a control line. Both imBMSCs and imBMSC41 exhibit long-term proliferative capability although imBMSC41 cells have a higher proliferation rate. SV40T mRNA expression is 130% higher in imBMSC41 than that in imBMSCs. However, FLP expression leads to 86% reduction of SV40T expression in imBMSCs, compared with 63% in imBMSC41 cells. Quantitative genomic PCR analysis indicates that the average copy number of SV40T and hygromycin is 1.05 for imBMSCs and 2.07 for imBMSC41, respectively. Moreover, FLP expression removes 92% of SV40T in imBMSCs at the genome DNA level, compared with 58% of that in imBMSC41 cells, indicating CRISPR/Cas9 HDR-mediated immortalization of BMSCs can be more effectively reversed than that of retrovirus-mediated random integrations. Nonetheless, both imBMSCs and imBMSC41 lines express MSC markers and are highly responsive to BMP9-induced osteogenic, chondrogenic and adipogenic differentiation in vitro and in vivo. Thus, the engineered imBMSCs can be used as a promising alternative source of primary MSCs for basic and translational research in the fields of MSC biology and regenerative medicine. PMID:29340096

Production of an aminoterminally truncated, stable type of bioactive mouse fibroblast growth factor 4 in Escherichia coli.

PubMed

Sugawara, Saiko; Ito, Toshihiko; Sato, Shiori; Sato, Yuki; Kasuga, Kano; Kojima, Ikuo; Kobayashi, Masayuki

2014-05-01

In mice, fibroblast growth factor 4 (Fgf4) is a crucial gene for the generation of trophectoderm, progenitor cells of the placenta. Therefore, exogenous FGF4 promotes the isolation and maintenance of trophoblast stem cells from preimplantation embryos. We previously produced a 6× histidine (His)-tagged, mouse FGF4 (Pro(31)-Leu(202)) without a secretory signal peptide at the amino-terminus, referred to as HismFGF4, in Escherichia coli. Here, we found that HismFGF4 was unstable, such as in phosphate-buffered saline. In these conditions, site-specific cleavage between Ser(50) and Leu(51) was identified. In order to generate stable mouse FGF4 derivatives, a 6× His-tagged mouse FGF4 (Leu(51)-Leu(202)), termed HismFGF4L, was expressed in E. coli. HismFGF4L could be purified from the supernatant of cell lysates by heparin column chromatography. In phosphate-buffered saline, HismFGF4L was relatively stable. HismFGF4L exerted significant mitogenic activities at concentrations as low as 0.01 nM (P < 0.01) in mouse embryonic fibroblast Balb/c 3T3 cells expressing FGF receptor 2. In the presence of PD173074, an FGF receptor inhibitor, the growth-promoting activity of HismFGF4L was abolished. Taken together, we suggest that aminoterminally truncated HismFGF4L is capable of promoting the proliferation of mouse-derived cells via an authentic FGF signaling pathway. We consider that HismFGF4L is useful as a derivative of mouse FGF4 protein for analyzing the effects of mouse FGF4 and for stimulating cell growth of mouse-derived cells, such as trophoblast stem cells. Our study provides a simple method for the production of a bioactive, stable mouse FGF4 derivative in E. coli. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Regional Retinal Ganglion Cell Axon Loss in a Murine Glaucoma Model

PubMed Central

Schaub, Julie A.; Kimball, Elizabeth C.; Steinhart, Matthew R.; Nguyen, Cathy; Pease, Mary E.; Oglesby, Ericka N.; Jefferys, Joan L.; Quigley, Harry A.

2017-01-01

Purpose To determine if retinal ganglion cell (RGC) axon loss in experimental mouse glaucoma is uniform in the optic nerve. Methods Experimental glaucoma was induced for 6 weeks with a microbead injection model in CD1 (n = 78) and C57BL/6 (B6, n = 68) mice. From epoxy-embedded sections of optic nerve 1 to 2 mm posterior to the globe, total nerve area and regional axon density (axons/1600 μm2) were measured in superior, inferior, nasal, and temporal zones. Results Control eyes of CD1 mice have higher axon density and more total RGCs than control B6 mice eyes. There were no significant differences in control regional axon density in all mice or by strain (all P > 0.2, mixed model). Exposure to elevated IOP caused loss of RGC in both strains. In CD1 mice, axon density declined without significant loss of nerve area, while B6 mice had less density loss, but greater decrease in nerve area. Axon density loss in glaucoma eyes was not significantly greater in any region in either mouse strain (both P > 0.2, mixed model). In moderately damaged CD1 glaucoma eyes, and CD1 eyes with the greatest IOP elevation exposure, density loss differed by region (P = 0.05, P = 0.03, mixed model) with the greatest loss in the temporal and superior regions, while in severely injured B6 nerves superior loss was greater than inferior loss (P = 0.01, mixed model, Bonferroni corrected). Conclusions There was selectively greater loss of superior and temporal optic nerve axons of RGCs in mouse glaucoma at certain stages of damage. Differences in nerve area change suggest non-RGC responses differ between mouse strains. PMID:28549091

Coordinated maturational regulation of PHEX and renal phosphate transport inhibitory activity: evidence for the pathophysiological role of PHEX in X-linked hypophosphatemia.

PubMed

Nesbitt, T; Fujiwara, I; Thomas, R; Xiao, Z S; Quarles, L D; Drezner, M K

1999-12-01

The mechanism by which inactivating mutations of PHEX (phosphate-regulating gene with homologies to endopeptidases on the X chromosome) cause X-linked hypophosphatemia remains unknown. However, recent reports suggest errant PHEX activity in osteoblasts may fail to inactivate a phosphaturic factor produced by these cells. To test this possibility, we examined coordinated maturational expression of PHEX and production of phosphate transport inhibitory activity in osteoblasts from normal and hyp-mice. We assessed the inhibitory activity in conditioned medium by examining the effects on opossum kidney cell phosphate transport and osteoblast PHEX expression by reverse transcriptase-polymerase chain reaction during a 17-day maturational period. Inhibitory activity increased as a function of osteoblast maturational stage, with no activity after 3 days and persistent activity by 6 days of culture. More significantly, equal phosphate transport inhibitory activity in conditioned medium from normal and hyp-mouse osteoblasts (control 1.90 +/- 0.12, normal 1.48 +/- 0.10, hyp 1.45 +/- 0.04 nmol/mg of protein/minute) was observed at 6 days. However, by 10 days hyp-mouse osteoblasts exhibited greater inhibitory activity than controls, and by 17 days the difference in phosphate transport inhibition maximized (control 2.08 +/- 0.09, normal 1.88 +/- 0.06, hyp 1.58 +/- 0.06 nmol/mg of protein/minute). Concurrently, we observed absent PHEX expression in normal osteoblasts after 3 days, limited production at 6 days, and significant production by day 10 of culture, while hyp-mouse osteoblasts exhibited limited PHEX activity secondary to an inactivating mutation. The data suggest that the presence of inactivating PHEX mutations results in the enhanced renal phosphate transport inhibitory activity exhibited by hyp-mouse osteoblasts.

β-Catenin activation regulates tissue growth non-cell autonomously in the hair stem cell niche.

PubMed

Deschene, Elizabeth R; Myung, Peggy; Rompolas, Panteleimon; Zito, Giovanni; Sun, Thomas Yang; Taketo, Makoto M; Saotome, Ichiko; Greco, Valentina

2014-03-21

Wnt/β-catenin signaling is critical for tissue regeneration. However, it is unclear how β-catenin controls stem cell behaviors to coordinate organized growth. Using live imaging, we show that activation of β-catenin specifically within mouse hair follicle stem cells generates new hair growth through oriented cell divisions and cellular displacement. β-Catenin activation is sufficient to induce hair growth independently of mesenchymal dermal papilla niche signals normally required for hair regeneration. Wild-type cells are co-opted into new hair growths by β-catenin mutant cells, which non-cell autonomously activate Wnt signaling within the neighboring wild-type cells via Wnt ligands. This study demonstrates a mechanism by which Wnt/β-catenin signaling controls stem cell-dependent tissue growth non-cell autonomously and advances our understanding of the mechanisms that drive coordinated regeneration.

Mitotic Defects Lead to Pervasive Aneuploidy and Accompany Loss of RB1 Activity in Mouse LmnaDhe Dermal Fibroblasts

PubMed Central

Pratt, C. Herbert; Curtain, Michelle; Donahue, Leah Rae; Shopland, Lindsay S.

2011-01-01

Background Lamin A (LMNA) is a component of the nuclear lamina and is mutated in several human diseases, including Emery-Dreifuss muscular dystrophy (EDMD; OMIM ID# 181350) and the premature aging syndrome Hutchinson-Gilford progeria syndrome (HGPS; OMIM ID# 176670). Cells from progeria patients exhibit cell cycle defects in both interphase and mitosis. Mouse models with loss of LMNA function have reduced Retinoblastoma protein (RB1) activity, leading to aberrant cell cycle control in interphase, but how mitosis is affected by LMNA is not well understood. Results We examined the cell cycle and structural phenotypes of cells from mice with the Lmna allele, Disheveled hair and ears (LmnaDhe). We found that dermal fibroblasts from heterozygous LmnaDhe (LmnaDhe/+) mice exhibit many phenotypes of human laminopathy cells. These include severe perturbations to the nuclear shape and lamina, increased DNA damage, and slow growth rates due to mitotic delay. Interestingly, LmnaDhe/+ fibroblasts also had reduced levels of hypophosphorylated RB1 and the non-SMC condensin II-subunit D3 (NCAP-D3), a mitosis specific centromere condensin subunit that depends on RB1 activity. Mitotic check point control by mitotic arrest deficient-like 1 (MAD2L1) also was perturbed in LmnaDhe /+ cells. LmnaDhe /+ fibroblasts were consistently aneuploid and had higher levels of micronuclei and anaphase bridges than normal fibroblasts, consistent with chromosome segregation defects. Conclusions These data indicate that RB1 may be a key regulator of cellular phenotype in laminopathy-related cells, and suggest that the effects of LMNA on RB1 include both interphase and mitotic cell cycle control. PMID:21464947

Developing Novel Therapeutic Approaches in Small Cell Lung Carcinoma Using Genetically Engineered Mouse Models and Human Circulating Tumor Cells

DTIC Science & Technology

2014-10-01

AD_________________ Award Number: W81XWH-13-1-0325 TITLE: Developing Novel Therapeutic Approaches in Small Cell Lung Carcinoma Using ...Genetically Engineered Mouse Models and Human Circulating Tumor Cells PRINCIPAL INVESTIGATOR: Jeffrey Engelman MD PhD CONTRACTING ORGANIZATION ...Novel Therapeutic Approaches in Small Cell Lung 5a. CONTRACT NUMBER W81XWH-13-1-0325 Carcinoma Using Genetically Engineered Mouse Models and 5b

Performance evaluation of the Abbott CELL-DYN Emerald for use as a bench-top analyzer in a research setting.

PubMed

Khoo, T-L; Xiros, N; Guan, F; Orellana, D; Holst, J; Joshua, D E; Rasko, J E J

2013-08-01

The CELL-DYN Emerald is a compact bench-top hematology analyzer that can be used for a three-part white cell differential analysis. To determine its utility for analysis of human and mouse samples, we evaluated this machine against the larger CELL-DYN Sapphire and Sysmex XT2000iV hematology analyzers. 120 human (normal and abnormal) and 30 mouse (normal and abnormal) samples were analyzed on both the CELL-DYN Emerald and CELL-DYN Sapphire or Sysmex XT2000iV analyzers. For mouse samples, the CELL-DYN Emerald analyzer required manual recalibration based on the histogram populations. Analysis of the CELL-DYN Emerald showed excellent precision, within accepted ranges (white cell count CV% = 2.09%; hemoglobin CV% = 1.68%; platelets CV% = 4.13%). Linearity was excellent (R² ≥ 0.99), carryover was minimal (<1%), and overall interinstrument agreement was acceptable for both human and mouse samples. Comparison between the CELL-DYN Emerald and Sapphire analyzers for human samples or Sysmex XT2000iV analyzer for mouse samples showed excellent correlation for all parameters. The CELL-DYN Emerald was generally comparable to the larger reference analyzer for both human and mouse samples. It would be suitable for use in satellite research laboratories or as a backup system in larger laboratories. © 2012 John Wiley & Sons Ltd.

A head movement image (HMI)-controlled computer mouse for people with disabilities.

PubMed

Chen, Yu-Luen; Chen, Weoi-Luen; Kuo, Te-Son; Lai, Jin-Shin

2003-02-04

This study proposes image processing and microprocessor technology for use in developing a head movement image (HMI)-controlled computer mouse system for the spinal cord injured (SCI). The system controls the movement and direction of the mouse cursor by capturing head movement images using a marker installed on the user's headset. In the clinical trial, this new mouse system was compared with an infrared-controlled mouse system on various tasks with nine subjects with SCI. The results were favourable to the new mouse system. The differences between the new mouse system and the infrared-controlled mouse were reaching statistical significance in each of the test situations (p<0.05). The HMI-controlled computer mouse improves the input speed. People with disabilities need only wear the headset and move their heads to freely control the movement of the mouse cursor.

Splenic morphological changes are accompanied by altered baseline immunity in a mouse model of sickle-cell disease.

PubMed

Szczepanek, Steven M; McNamara, Jeffrey T; Secor, Eric R; Natarajan, Prabitha; Guernsey, Linda A; Miller, Lauren A; Ballesteros, Enrique; Jellison, Evan; Thrall, Roger S; Andemariam, Biree

2012-11-01

Although functional asplenia from infarctions may be a major contributor to increased infectious mortality in sickle-cell disease (SCD), this relationship has not been fully defined. We used the transgenic Berkeley SCD mouse to define blood and splenic immunophenotypic differences in this model compared with C57BL/6 and hemizygous controls. In the serum of SCD mice, we found increased IgG2a and suppressed IgM, IgG2b, and IgA levels. Serum IL-6 levels in SCD mice were elevated, whereas IL-1α, CXCL10, and CCL5 levels were decreased. The blood of SCD mice had higher white blood cell counts, with an increased percentage of lymphocytes and decreases in other leukocytes. Immunophenotyping of lymphocytes revealed higher percentages of CD8(+) and T-regulatory cells and lower percentages of B cells. SCD mouse spleens exhibited histological disorganization, with reduction of defined lymphoid follicles and expansion of red pulp, a greater than fourfold increase in splenic mononuclear cells, marked expansion of the nucleated red blood cell fraction, and B-cell and CD8(+) T-cell lymphopenia. Within the splenic B-cell population, there was a significant decrease in B-1a B cells, with a corresponding decrease in IgA secreting plasma cells in the gut. Confocal microscopy of spleens demonstrated complete disruption of the normal lymphofollicular structure in the white pulp of SCD mice without distinct B, T, and marginal zones. Our findings suggest that altered SCD splenic morphological characteristics result in an impaired systemic immune response. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Efficient CRISPR-mediated mutagenesis in primary immune cells using CrispRGold and a C57BL/6 Cas9 transgenic mouse line.

PubMed

Chu, Van Trung; Graf, Robin; Wirtz, Tristan; Weber, Timm; Favret, Jeremy; Li, Xun; Petsch, Kerstin; Tran, Ngoc Tung; Sieweke, Michael H; Berek, Claudia; Kühn, Ralf; Rajewsky, Klaus

2016-11-01

Applying clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9)-mediated mutagenesis to primary mouse immune cells, we used high-fidelity single guide RNAs (sgRNAs) designed with an sgRNA design tool (CrispRGold) to target genes in primary B cells, T cells, and macrophages isolated from a Cas9 transgenic mouse line. Using this system, we achieved an average knockout efficiency of 80% in B cells. On this basis, we established a robust small-scale CRISPR-mediated screen in these cells and identified genes essential for B-cell activation and plasma cell differentiation. This screening system does not require deep sequencing and may serve as a precedent for the application of CRISPR/Cas9 to primary mouse cells.

Lead induces apoptosis in mouse TM3 Leydig cells through the Fas/FasL death receptor pathway.

PubMed

He, Xiuyuan; Wu, Jing; Yuan, Liyun; Lin, Feng; Yi, Jine; Li, Jing; Yuan, Hui; Shi, Jinling; Yuan, Tingting; Zhang, Shufang; Fan, Yongheng; Zhao, Zhihang

2017-12-01

The study was aimed to investigate the effect of Pb toxicity on mouse Leydig cells and its molecular mechanism. The TM3 cells were cultured in vitro and exposed to Pb at different concentrations for 24h. The effects of Pb on cell proliferation and apoptosis were analyzed with MTT and Annexin V-FITC/PI via flow cytometry, respectively. Expression levels of Fas, Fas-L and caspase-8 in TM3 cells were determined by western blot. As well as the inhibitory effect of the caspase-8 inhibitor Z-IETD-FMK on cell apoptosis. We found that Pb treatment significantly decreased the cellar viability (P<0.05), increased the apoptosis (P<0.01) and the Fas, FasL, and caspase-8 expression levels in Pb-treated cells as compared to the control cells (P<0.05 or P<0.01). Furthermore, the caspase-8 inhibitor effectively block the Pb-induced cell apoptosis. Taken together, our data suggest that Pb-induced TM3 cell toxic effect may involve in the Fas/FasL death receptor signaling pathway. Copyright © 2017. Published by Elsevier B.V.

Control of myogenesis by rodent SINE-containing lncRNAs

PubMed Central

Wang, Jiashi; Gong, Chenguang; Maquat, Lynne E.

2013-01-01

Staufen1-mediated mRNA decay (SMD) degrades mRNAs that harbor a Staufen1-binding site (SBS) in their 3′ untranslated regions (UTRs). Human SBSs can form by intermolecular base-pairing between a 3′ UTR Alu element and an Alu element within a long noncoding RNA (lncRNA) called a ½-sbsRNA. Since Alu elements are confined to primates, it was unclear how SMD occurs in rodents. Here we identify mouse mRNA 3′ UTRs and lncRNAs that contain a B1, B2, B4, or identifier (ID) element. We show that SMD occurs in mouse cells via mRNA–lncRNA base-pairing of partially complementary elements and that mouse ½-sbsRNA (m½-sbsRNA)-triggered SMD regulates C2C12 cell myogenesis. Our findings define new roles for lncRNAs as well as B and ID short interspersed elements (SINEs) in mice that undoubtedly influence many developmental and homeostatic pathways. PMID:23558772

CCL11 elicits secretion of RNases from mouse eosinophils and their cell-free granules

PubMed Central

Shamri, Revital; Melo, Rossana C. N.; Young, Kristen M.; Bivas-Benita, Maytal; Xenakis, Jason J.; Spencer, Lisa A.; Weller, Peter F.

2012-01-01

Rapid secretion of eosinophil-associated RNases (EARs), such as the human eosinophilic cationic protein (ECP), from intracellular granules is central to the role of eosinophils in allergic diseases and host immunity. Our knowledge regarding allergic inflammation has advanced based on mouse experimental models. However, unlike human eosinophils, capacities of mouse eosinophils to secrete granule proteins have been controversial. To study mechanisms of mouse eosinophil secretion and EAR release, we combined an RNase assay of mouse EARs with ultrastructural studies. In vitro, mouse eosinophils stimulated with the chemokine eotaxin-1 (CCL11) secreted enzymatically active EARs (EC50 5 nM) by piecemeal degranulation. In vivo, in a mouse model of allergic airway inflammation, increased airway eosinophil infiltration (24-fold) correlated with secretion of active RNases (3-fold). Moreover, we found that eosinophilic inflammation in mice can involve eosinophil cytolysis and release of cell-free granules. Cell-free mouse eosinophil granules expressed functional CCR3 receptors and secreted their granule proteins, including EAR and eosinophil peroxidase in response to CCL11. Collectively, these data demonstrate chemokine-dependent secretion of EARs from both intact mouse eosinophils and their cell-free granules, findings pertinent to understanding the pathogenesis of eosinophil-associated diseases, in which EARs are key factors.—Shamri, R., Melo, R. C. N., Young, K. M., B.-B, M., Xenakis, J. J., Spencer, L. A., Weller, P. F. CCL11 elicits secretion of RNases from mouse eosinophils and their cell-free granules. PMID:22294786

Human fused NKG2D-IL-15 protein controls xenografted human gastric cancer through the recruitment and activation of NK cells.

PubMed

Chen, Yan; Chen, Bei; Yang, Ti; Xiao, Weiming; Qian, Li; Ding, Yanbing; Ji, Mingchun; Ge, Xiaoqun; Gong, Weijuan

2017-03-01

Interleukin (IL)-15 plays an important role in natural killer (NK) and CD8+ T-cell proliferation and function and is more effective than IL-2 for tumor immunotherapy. The trans-presentation of IL-15 by neighboring cells is more effective for NK cell activation than its soluble IL-15. In this study, the fusion protein dsNKG2D-IL-15, which consisted of two identical extracellular domains of human NKG2D coupled to human IL-15 via a linker, was engineered in Escherichia coli. DsNKG2D-IL-15 could efficiently bind to major histocompatibility complex class I chain-related protein A (MICA) of human tumor cells with the two NKG2D domains and trans-present IL-15 to NK or CD8+ T cells. We transplanted human gastric cancer (SGC-7901) cells into nude mice and mouse melanoma cells with ectopic expression of MICA (B16BL6-MICA) into C57BL/6 mice. Then, we studied the anti-tumor effects mediated by dsNKG2D-IL-15 in the two xenografted tumor models. Human dsNKG2D-IL-15 exhibited higher efficiency than IL-15 in suppressing gastric cancer growth. Exogenous human dsNKG2D-IL-15 was centrally distributed in the mouse tumor tissues based on in vivo live imaging. The frequencies of human CD56+ cells infiltrated into the tumor tissues following the injection of peripheral blood mononuclear cells into nude mice bearing human gastric cancer were significantly increased by human dsNKG2D-IL-15 treatment. Human dsNKG2D-IL-15 also delayed the growth of transplanted melanoma (B16BL6-MICA) by activating and recruiting mouse NK and CD8+ T cells. The anti-melanoma effect of human dsNKG2D-IL-15 in C57BL/6 mice was mostly decreased by the in vivo depletion of mouse NK cells. These data highlight the potential use of human dsNKG2D-IL-15 for tumor therapy.Cellular & Molecular Immunology advance online publication, 14 September 2015; doi:10.1038/cmi.2015.81.

Contractile reserve and intracellular calcium regulation in mouse myocytes from normal and hypertrophied failing hearts

NASA Technical Reports Server (NTRS)

Ito, K.; Yan, X.; Tajima, M.; Su, Z.; Barry, W. H.; Lorell, B. H.; Schneider, M. (Principal Investigator)

2000-01-01

Mouse myocyte contractility and the changes induced by pressure overload are not fully understood. We studied contractile reserve in isolated left ventricular myocytes from mice with ascending aortic stenosis (AS) during compensatory hypertrophy (4-week AS) and the later stage of early failure (7-week AS) and from control mice. Myocyte contraction and [Ca(2+)](i) transients with fluo-3 were measured simultaneously. At baseline (0.5 Hz, 1.5 mmol/L [Ca(2+)](o), 25 degrees C), the amplitude of myocyte shortening and peak-systolic [Ca(2+)](i) in 7-week AS were not different from those of controls, whereas contraction, relaxation, and the decline of [Ca(2+)](i) transients were slower. In response to the challenge of high [Ca(2+)](o), fractional cell shortening was severely depressed with reduced peak-systolic [Ca(2+)](i) in 7-week AS compared with controls. In response to rapid pacing stimulation, cell shortening and peak-systolic [Ca(2+)](i) increased in controls, but this response was depressed in 7-week AS. In contrast, the responses to both challenge with high [Ca(2+)](o) and rapid pacing in 4-week AS were similar to those of controls. Although protein levels of Na(+)-Ca(2+) exchanger were increased in both 4-week and 7-week AS, the ratio of SR Ca(2+)-ATPase to phospholamban protein levels was depressed in 7-week AS compared with controls but not in 4-week AS. This was associated with an impaired capacity to increase sarcoplasmic reticulum Ca(2+) load during high work states in 7-week AS myocytes. In hypertrophied failing mouse myocytes, depressed contractile reserve is related to an impaired augmentation of systolic [Ca(2+)](i) and SR Ca(2+) load and simulates findings in human failing myocytes.

In vitro bioactivity of Bioroot™ RCS, via A4 mouse pulpal stem cells.

PubMed

Dimitrova-Nakov, Sasha; Uzunoglu, Emel; Ardila-Osorio, Hector; Baudry, Anne; Richard, Gilles; Kellermann, Odile; Goldberg, Michel

2015-11-01

To evaluate the biocompatibility and osteoinductive properties of Bioroot™ RCS (BR, Septodont, France) compared to Kerr's Pulp Canal Sealer™ (PCS, Kerr, Italy) using the mouse pulp-derived stem cell line A4, which have an osteo/odontogenic potential in vitro and contribute to efficient bone repair in vivo. A4 cells were cultured at the stem cell stage in the presence of solid disks of BR or PCS, whereas untreated A4 cells were used as control. After 3, 7, 10 days of direct contact with the sealers, cell viability was quantified using Trypan Blue exclusion assay. Immunolabelings were performed to assess the expression of odontoblast markers i.e. type 1 collagen, DMP1 or BSP. Finally, sealer-treated cells were induced toward osteo/odontogenic differentiation to assess the impact of the sealers on mineralization by Von Kossa staining. Statistical significance was evaluated by one-way analysis of variance and t-test (p<0.05). BR did not alter the viability and morphology of A4 pulpal cells compared to control group (p>0.05); however, living cell percentage of PCS was significantly lower compared to control and BR groups (p<0.05). BR preserved the intrinsic ability of A4 cells to express type 1 collagen, DMP1 or BSP at the stem cell stage. It did not alter the integrity of collagen fibers surrounding the cells and promoted overexpression of BSP and DMP1 at the cell surface. In contrast to PCS, BR did not compromise the mineralization potential of pulpal A4 stem cells. Bioroot™ RCS was not as cytotoxic as PCS. It did not recruit the pulpal stem cells toward differentiation but preserve their osteo-odontogenic intrinsic properties. Bioroot™ RCS might provide more suitable environment to induce stem cells for hard tissue deposition. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Micropattern differentiation of mouse pluripotent stem cells recapitulates embryo regionalized cell fate patterning

PubMed Central

Morgani, Sophie M; Metzger, Jakob J; Nichols, Jennifer

2018-01-01

During gastrulation epiblast cells exit pluripotency as they specify and spatially arrange the three germ layers of the embryo. Similarly, human pluripotent stem cells (PSCs) undergo spatially organized fate specification on micropatterned surfaces. Since in vivo validation is not possible for the human, we developed a mouse PSC micropattern system and, with direct comparisons to mouse embryos, reveal the robust specification of distinct regional identities. BMP, WNT, ACTIVIN and FGF directed mouse epiblast-like cells to undergo an epithelial-to-mesenchymal transition and radially pattern posterior mesoderm fates. Conversely, WNT, ACTIVIN and FGF patterned anterior identities, including definitive endoderm. By contrast, epiblast stem cells, a developmentally advanced state, only specified anterior identities, but without patterning. The mouse micropattern system offers a robust scalable method to generate regionalized cell types present in vivo, resolve how signals promote distinct identities and generate patterns, and compare mechanisms operating in vivo and in vitro and across species. PMID:29412136

Therapeutic effects of autologous lymphocytes activated with trastuzumab for xenograft mouse models of human breast cancer.

PubMed

Nakagawa, Shinichiro; Matsuoka, Yusuke; Ichihara, Hideaki; Yoshida, Hitoji; Yoshida, Kenshi; Ueoka, Ryuichi

2013-01-01

Trastuzumab (TTZ) is molecular targeted drug used for metastatic breast cancer patients overexpressing human epidermal growth factor receptor 2 (HER2). Therapeutic effects of lymphocytes activated with TTZ (TTZ-LAK) using xenograft mouse models of human breast cancer (MDA-MB-453) cells were examined in vivo. Remarkable reduction of tumor volume in a xenograft mouse models intravenously treated with TTZ-LAK cells after the subcutaneously inoculated of MDA-MB-453 cells was verified in vivo. The migration of TTZ-LAK cells in tumor of mouse models subcutaneously inoculated MDA-MB-453 cells was observed on the basis of histological analysis using immunostaining with CD-3. Induction of apoptosis in tumor of xenograft mice treated with TTZ-LAK cells was observed in micrographs using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) method. It was noteworthy that the therapeutic effects of TTZ-LAK cells along with apoptosis were obtained for xenograft mouse models of human breast tumor in vivo.

Treatment of hypoxic-ischemic encephalopathy in mouse by transplantation of embryonic stem cell-derived cells.

PubMed

Ma, Jie; Wang, Yu; Yang, Jianhua; Yang, Min; Chang, Keun-A; Zhang, Linhua; Jiang, Feng; Li, Yi; Zhang, Zhonggong; Heo, Chaejeong; Suh, Yoo-Hun

2007-07-01

A 7-day-old hypoxic-ischemic encephalopathy (HIE) mouse model was used to study the effect of transplantation of embryonic stem (ES) cell-derived cells on the HIE. After the inducement in vitro, the ES cell-derived cells expressed Nestin and MAP-2, rather than GFAP mRNA. After transplantation, ES cell-derived cells can survive, migrate into the injury site, and specifically differentiate into neurons, showing improvement of the learning ability and memory of the HIE mouse at 8 months post-transplantation. The non-grafted HIE mouse brain showed typical pathological changes in the hippocampus and cerebral cortex, where the number of neurons was reduced, while in the cell graft group, number of the neurons increased in the same regions. Although further study is necessary to elucidate the precise mechanisms responsible for this functional recovery, we believe that ES cells have advantages for use as a donor source in HIE.

The toxicity, in vitro, of silicon carbide whiskers.

PubMed

Vaughan, G L; Jordan, J; Karr, S

1991-10-01

To mouse cells in culture, SiC whiskers (SiCW) and asbestos are similarly cytotoxic, disrupting cell membranes and killing cells. Both shorten cell generation time, increase the rate of DNA synthesis, increase total cell DNA content, and cause a loss in growth control often associated with malignant cellular transformation. Within the narrow size range of materials examined, the amount of damage appeared to be more a function of the number of whiskers present than of their size. Silicon carbide whiskers, if mishandled, may pose a serious health hazard to humans.

Pitfalls using tyramide signal amplification (TSA) in the mouse gastrointestinal tract: endogenous streptavidin-binding sites lead to false positive staining.

PubMed

Horling, L; Neuhuber, W L; Raab, M

2012-02-15

Highly sensitive immunohistochemical detection systems such as tyramide signal amplification (TSA) are widely used, since they allow using two primary antibodies raised in the same species. Most of them are based on the streptavidin-biotin-peroxidase system and include streptavidin-coupled secondary antibodies. Using TSA in cryostat-sectioned tissues of mouse esophagus, we were puzzled by negative controls with unexpected staining mostly in the ganglionic areas. This prompted us to search for the causing agent and to include also other parts of the mouse gastrointestinal tract for comparison. Streptavidin-coupled antibodies bound to endogenous binding sites yet to be characterized, which are present throughout the mouse intestines. Staining was mainly localized around neuronal cell bodies of enteric ganglia. Thus, caution is warranted when applying streptavidin-coupled antibodies in the mouse gastrointestinal tract. The use of endogenous biotin-blocking kits combined with a prolonged post-fixation time could significantly reduce unintentional staining. Copyright © 2011 Elsevier B.V. All rights reserved.

Reciprocal Expression of lin-41 and the microRNAs let-7 and mir-125 During Mouse Embryogenesis

PubMed Central

Schulman, Betsy R. Maller; Esquela-Kerscher, Aurora; Slack, Frank J.

2008-01-01

In C. elegans, heterochronic genes control the timing of cell fate determination during development. Two heterochronic genes, let-7 and lin-4, encode microRNAs (miRNAs) that down-regulate a third heterochronic gene lin-41 by binding to complementary sites in its 3’UTR. let-7 and lin-4 are conserved in mammals. Here we report the cloning and sequencing of mammalian lin-41 orthologs. We find that mouse and human lin-41 genes contain predicted conserved complementary sites for let-7 and the lin-4 ortholog, mir-125, in their 3’UTRs. Mouse lin-41 (Mlin-41) is temporally expressed in developing mouse embryos, most dramatically in the limb buds. Mlin-41 is down-regulated during mid-embryogenesis at the time when mouse let-7c and mir-125 RNA levels are up-regulated. Our results suggest that mammalian lin-41 is temporally regulated by miRNAs in order to direct key developmental events such as limb formation. PMID:16247770

Establishment of mouse expanded potential stem cells

PubMed Central

Gao, Xuefei; Antunes, Liliana; Yu, Yong; Zhu, Zhexin; Wang, Juexuan; Kolodziejczyk, Aleksandra A.; Campos, Lia S.; Wang, Cui; Yang, Fengtang; Zhong, Zhen; Fu, Beiyuan; Eckersley-Maslin, Melanie A.; Woods, Michael; Tanaka, Yosuke; Chen, Xi; Wilkinson, Adam C.; Bussell, James; White, Jacqui; Ramirez-Solis, Ramiro; Reik, Wolf; Göttgens, Berthold; Teichmann, Sarah A.; Tam, Patrick P. L.; Nakauchi, Hiromitsu; Zou, Xiangang; Lu, Liming; Liu, Pentao

2018-01-01

Mouse embryonic stem cells derived from the epiblast1 contribute to the somatic lineages and the germline but are excluded from the extra-embryonic tissues that are derived from the trophectoderm and the primitive endoderm2 upon reintroduction to the blastocyst. Here we report that cultures of expanded potential stem cells can be established from individual eight-cell blastomeres, and by direct conversion of mouse embryonic stem cells and induced pluripotent stem cells. Remarkably, a single expanded potential stem cell can contribute both to the embryo proper and to the trophectoderm lineages in a chimaera assay. Bona fide trophoblast stem cell lines and extra-embryonic endoderm stem cells can be directly derived from expanded potential stem cells in vitro. Molecular analyses of the epigenome and single-cell transcriptome reveal enrichment for blastomere-specific signature and a dynamic DNA methylome in expanded potential stem cells. The generation of mouse expanded potential stem cells highlights the feasibility of establishing expanded potential stem cells for other mammalian species. PMID:29019987

Characterization of pancreatic glucagon-producing tumors and pituitary gland tumors in transgenic mice overexpressing MYCN in hGFAP-positive cells.

PubMed

Fielitz, Kathrin; Althoff, Kristina; De Preter, Katleen; Nonnekens, Julie; Ohli, Jasmin; Elges, Sandra; Hartmann, Wolfgang; Klöppel, Günter; Knösel, Thomas; Schulte, Marc; Klein-Hitpass, Ludger; Beisser, Daniela; Reis, Henning; Eyking, Annette; Cario, Elke; Schulte, Johannes H; Schramm, Alexander; Schüller, Ulrich

2016-11-15

Amplification or overexpression of MYCN is involved in development and maintenance of multiple malignancies. A subset of these tumors originates from neural precursors, including the most aggressive forms of the childhood tumors, neuroblastoma and medulloblastoma. In order to model the spectrum of MYCN-driven neoplasms in mice, we transgenically overexpressed MYCN under the control of the human GFAP-promoter that, among other targets, drives expression in neural progenitor cells. However, LSL-MYCN;hGFAP-Cre double transgenic mice did neither develop neural crest tumors nor tumors of the central nervous system, but presented with neuroendocrine tumors of the pancreas and, less frequently, the pituitary gland. Pituitary tumors expressed chromogranin A and closely resembled human pituitary adenomas. Pancreatic tumors strongly produced and secreted glucagon, suggesting that they derived from glucagon- and GFAP-positive islet cells. Interestingly, 3 out of 9 human pancreatic neuroendocrine tumors expressed MYCN, supporting the similarity of the mouse tumors to the human system. Serial transplantations of mouse tumor cells into immunocompromised mice confirmed their fully transformed phenotype. MYCN-directed treatment by AuroraA- or Brd4-inhibitors resulted in significantly decreased cell proliferation in vitro and reduced tumor growth in vivo. In summary, we provide a novel mouse model for neuroendocrine tumors of the pancreas and pituitary gland that is dependent on MYCN expression and that may help to evaluate MYCN-directed therapies.

Resveratrol Inhibited Hydroquinone-Induced Cytotoxicity in Mouse Primary Hepatocytes

PubMed Central

Wang, Da-Hong; Ootsuki, Yoshie; Fujita, Hirofumi; Miyazaki, Masahiro; Yie, Qinxia; Tsutsui, Ken; Sano, Kuniaki; Masuoka, Noriyoshi; Ogino, Keiki

2012-01-01

Hydroquinone (1,4-benzenediol) has been widely used in clinical situations and the cosmetic industry because of its depigmenting effects. Most skin-lightening hydroquinone creams contain 4%–5% hydroquinone. We have investigated the role of resveratrol in prevention of hydroquinone induced cytotoxicity in mouse primary hepatocytes. We found that 400 µM hydroquinone exposure alone induced apoptosis of the cells and also resulted in a significant drop of cell viability compared with the control, and pretreatment of resveratrol to a final concentration of 0.5 mM 1 h before hydroquinone exposure did not show a significant improvement in the survival rate of the hepatocytes, however, relatively higher concentrations of resveratrol (≥1 mM) inhibited apoptosis of the mouse primary hepatocytes and increased cell viability in a dose-dependent manner, and in particular the survival rate of the hepatocytes was recovered from 28% to near 100% by 5 mM resveratrol. Interestingly, pretreatment with resveratrol for longer time (24 h), even in very low concentrations (50 µM, 100 µM), blocked the damage of hydroquinone to the cells. We also observed that resveratrol pretreatment suppressed hydroquinone-induced expression of cytochrome P450 2E1 mRNA dose-dependently. The present study suggests that resveratrol protected the cells against hydroquinone-induced toxicity through its antioxidant function and possibly suppressive effect on the expression of cytochrome P450 2E1. PMID:23202692

Resveratrol inhibited hydroquinone-induced cytotoxicity in mouse primary hepatocytes.

PubMed

Wang, Da-Hong; Ootsuki, Yoshie; Fujita, Hirofumi; Miyazaki, Masahiro; Yie, Qinxia; Tsutsui, Ken; Sano, Kuniaki; Masuoka, Noriyoshi; Ogino, Keiki

2012-09-19

Hydroquinone (1,4-benzenediol) has been widely used in clinical situations and the cosmetic industry because of its depigmenting effects. Most skin-lightening hydroquinone creams contain 4%-5% hydroquinone. We have investigated the role of resveratrol in prevention of hydroquinone induced cytotoxicity in mouse primary hepatocytes. We found that 400 µM hydroquinone exposure alone induced apoptosis of the cells and also resulted in a significant drop of cell viability compared with the control, and pretreatment of resveratrol to a final concentration of 0.5 mM 1 h before hydroquinone exposure did not show a significant improvement in the survival rate of the hepatocytes, however, relatively higher concentrations of resveratrol (≥1 mM) inhibited apoptosis of the mouse primary hepatocytes and increased cell viability in a dose-dependent manner, and in particular the survival rate of the hepatocytes was recovered from 28% to near 100% by 5 mM resveratrol. Interestingly, pretreatment with resveratrol for longer time (24 h), even in very low concentrations (50 µM, 100 µM), blocked the damage of hydroquinone to the cells. We also observed that resveratrol pretreatment suppressed hydroquinone-induced expression of cytochrome P450 2E1 mRNA dose-dependently. The present study suggests that resveratrol protected the cells against hydroquinone-induced toxicity through its antioxidant function and possibly suppressive effect on the expression of cytochrome P450 2E1.

Inhibitory Effects of Leptin on Pancreatic α-Cell Function

PubMed Central

Tudurí, Eva; Marroquí, Laura; Soriano, Sergi; Ropero, Ana B.; Batista, Thiago M.; Piquer, Sandra; López-Boado, Miguel A.; Carneiro, Everardo M.; Gomis, Ramón; Nadal, Angel; Quesada, Ivan

2009-01-01

OBJECTIVE Leptin released from adipocytes plays a key role in the control of food intake, energy balance, and glucose homeostasis. In addition to its central action, leptin directly affects pancreatic β-cells, inhibiting insulin secretion, and, thus, modulating glucose homeostasis. However, despite the importance of glucagon secretion in glucose homeostasis, the role of leptin in α-cell function has not been studied in detail. In the present study, we have investigated this functional interaction. RESEARCH DESIGN AND METHODS The presence of leptin receptors (ObR) was demonstrated by RT-PCR analysis, Western blot, and immunocytochemistry. Electrical activity was analyzed by patch-clamp and Ca2+ signals by confocal microscopy. Exocytosis and glucagon secretion were assessed using fluorescence methods and radioimmunoassay, respectively. RESULTS The expression of several ObR isoforms (a–e) was detected in glucagon-secreting αTC1-9 cells. ObRb, the main isoform involved in leptin signaling, was identified at the protein level in αTC1-9 cells as well as in mouse and human α-cells. The application of leptin (6.25 nmol/l) hyperpolarized the α-cell membrane potential, suppressing the electrical activity induced by 0.5 mmol/l glucose. Additionally, leptin inhibited Ca2+ signaling in αTC1-9 cells and in mouse and human α-cells within intact islets. A similar result occurred with 0.625 nmol/l leptin. These effects were accompanied by a decrease in glucagon secretion from mouse islets and were counteracted by the phosphatidylinositol 3-kinase inhibitor, wortmannin, suggesting the involvement of this pathway in leptin action. CONCLUSIONS These results demonstrate that leptin inhibits α-cell function, and, thus, these cells are involved in the adipoinsular communication. PMID:19401420

Global gene expression analysis in a mouse model for Norrie disease: late involvement of photoreceptor cells.

PubMed

Lenzner, Steffen; Prietz, Sandra; Feil, Silke; Nuber, Ulrike A; Ropers, H-Hilger; Berger, Wolfgang

2002-09-01

Mutations in the NDP gene give rise to a variety of eye diseases, including classic Norrie disease (ND), X-linked exudative vitreoretinopathy (EVRX), retinal telangiectasis (Coats disease), and advanced retinopathy of prematurity (ROP). The gene product is a cystine-knot-containing extracellular signaling molecule of unknown function. In the current study, gene expression was determined in a mouse model of ND, to unravel disease-associated mechanisms at the molecular level. Gene transcription in the eyes of 2-year-old Ndp knockout mice was compared with that in the eyes of age-matched wild-type control animals, by means of cDNA subtraction and microarrays. Clones (n = 3072) from the cDNA subtraction libraries were spotted onto glass slides and hybridized with fluorescently labeled RNA-derived targets. More than 230 differentially expressed clones were sequenced, and their expression patterns were verified by virtual Northern blot analysis. Numerous gene transcripts that are absent or downregulated in the eye of Ndp knockout mice are photoreceptor cell specific. In younger Ndp knockout mice (up to 1 year old), however, all these transcripts were found to be expressed at normal levels. The identification of numerous photoreceptor cell-specific transcripts with a reduced expression in 2-year-old, but not in young, Ndp knockout mice indicates that normal gene expression in these light-sensitive cells of mutant mice is established and maintained over a long period and that rods and cones are affected relatively late in the mouse model of ND. Obviously, the absence of the Ndp gene product is not compatible with long-term survival of photoreceptor cells in the mouse.

Genetically Targeted All-Optical Electrophysiology with a Transgenic Cre-Dependent Optopatch Mouse

PubMed Central

Lou, Shan; Adam, Yoav; Weinstein, Eli N.; Williams, Erika; Williams, Katherine; Parot, Vicente; Kavokine, Nikita; Liberles, Stephen; Madisen, Linda; Zeng, Hongkui

2016-01-01

Recent advances in optogenetics have enabled simultaneous optical perturbation and optical readout of membrane potential in diverse cell types. Here, we develop and characterize a Cre-dependent transgenic Optopatch2 mouse line that we call Floxopatch. The animals expressed a blue-shifted channelrhodopsin, CheRiff, and a near infrared Archaerhodopsin-derived voltage indicator, QuasAr2, via targeted knock-in at the rosa26 locus. In Optopatch-expressing animals, we tested for overall health, genetically targeted expression, and function of the optogenetic components. In offspring of Floxopatch mice crossed with a variety of Cre driver lines, we observed spontaneous and optically evoked activity in vitro in acute brain slices and in vivo in somatosensory ganglia. Cell-type-specific expression allowed classification and characterization of neuronal subtypes based on their firing patterns. The Floxopatch mouse line is a useful tool for fast and sensitive characterization of neural activity in genetically specified cell types in intact tissue. SIGNIFICANCE STATEMENT Optical recordings of neural activity offer the promise of rapid and spatially resolved mapping of neural function. Calcium imaging has been widely applied in this mode, but is insensitive to the details of action potential waveforms and subthreshold events. Simultaneous optical perturbation and optical readout of single-cell electrical activity (“Optopatch”) has been demonstrated in cultured neurons and in organotypic brain slices, but not in acute brain slices or in vivo. Here, we describe a transgenic mouse in which expression of Optopatch constructs is controlled by the Cre-recombinase enzyme. This animal enables fast and robust optical measurements of single-cell electrical excitability in acute brain slices and in somatosensory ganglia in vivo, opening the door to rapid optical mapping of neuronal excitability. PMID:27798186

Intravitreal Injection of Proinsulin-Loaded Microspheres Delays Photoreceptor Cell Death and Vision Loss in the rd10 Mouse Model of Retinitis Pigmentosa.

PubMed

Isiegas, Carolina; Marinich-Madzarevich, Jorge A; Marchena, Miguel; Ruiz, José M; Cano, María J; de la Villa, Pedro; Hernández-Sánchez, Catalina; de la Rosa, Enrique J; de Pablo, Flora

2016-07-01

The induction of proinsulin expression by transgenesis or intramuscular gene therapy has been shown previously to retard retinal degeneration in mouse and rat models of retinitis pigmentosa (RP), a group of inherited conditions that result in visual impairment. We investigated whether intraocular treatment with biodegradable poly (lactic-co-glycolic) acid microspheres (PLGA-MS) loaded with proinsulin has cellular and functional neuroprotective effects in the retina. Experiments were performed using the Pde6brd10 mouse model of RP. Methionylated human recombinant proinsulin (hPI) was formulated in PLGA-MS, which were administered by intravitreal injection on postnatal days (P) 14 to 15. Retinal neuroprotection was assessed at P25 by electroretinography, and by evaluating outer nuclear layer (ONL) cellular preservation. The attenuation of photoreceptor cell death by hPI was determined by TUNEL assay in cultured P22 retinas, as well as Akt phosphorylation by immunoblotting. We successfully formulated hPI PLGA-MS to deliver the active molecule for several weeks in vitro. The amplitude of b-cone and mixed b-waves in electroretinographic recording was significantly higher in eyes injected with hPI-PLGA-MS compared to control eyes. Treatment with hPI-PLGA-MS attenuated photoreceptor cell loss, as revealed by comparing ONL thickness and the number of cell rows in this layer in treated versus untreated retinas. Finally, hPI prevented photoreceptor cell death and increased AktThr308 phosphorylation in organotypic cultured retinas. Retinal degeneration in the rd10 mouse was slowed by a single intravitreal injection of hPI-PLGA-MS. Human recombinant proinsulin elicited a rapid and effective neuroprotective effect when administered in biodegradable microspheres, which may constitute a future potentially feasible delivery method for proinsulin-based treatment of RP.

Cerebellar stem cells do not produce neurons and astrocytes in adult mouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Xin; Guan, Wuqiang; Yu, Yong-Chun

Highlights: • No new neurons and astrocytes are generated in adult mouse cerebellum. • Very few mash1{sup +} or nestin{sup +} stem cells exist, and most of them are quiescent. • Cell proliferation rate is diversified among cerebellar regions and decreases over time. - Abstract: Although previous studies implied that cerebellar stem cells exist in some adult mammals, little is known about whether these stem cells can produce new neurons and astrocytes. In this study by bromodeoxyuridine (BrdU) intraperitoneal (i.p.) injection, we found that there are abundant BrdU{sup +} cells in adult mouse cerebellum, and their quantity and density decreasesmore » significantly over time. We also found cell proliferation rate is diversified in different cerebellar regions. Among these BrdU{sup +} cells, very few are mash1{sup +} or nestin{sup +} stem cells, and the vast majority of cerebellar stem cells are quiescent. Data obtained by in vivo retrovirus injection indicate that stem cells do not produce neurons and astrocytes in adult mouse cerebellum. Instead, some cells labeled by retrovirus are Iba1{sup +} microglia. These results indicate that very few stem cells exist in adult mouse cerebellum, and none of these stem cells contribute to neurogenesis and astrogenesis under physiological condition.« less

Carbamazepine-hypersensitivity: assessment of clinical and in vitro chemical cross-reactivity with phenytoin and oxcarbazepine.

PubMed Central

Pirmohamed, M; Graham, A; Roberts, P; Smith, D; Chadwick, D; Breckenridge, A M; Park, B K

1991-01-01

1. Seven patients clinically diagnosed as being hypersensitive to carbamazepine and one patient hypersensitive to both carbamazepine and oxcarbazepine have been identified. They have been compared with a control group (hereafter referred to as 'control subjects') comprising five patients on chronic carbamazepine therapy without adverse effects and 12 healthy volunteers who have never been exposed to anticonvulsants. 2. An in vitro cytotoxicity assay employing mononuclear leucocytes as target cells has been used first, to determine the ability of 10 different human livers to bioactivate carbamazepine to a cytotoxic metabolite, and secondly, to compare the cell defences of carbamazepine-hypersensitive patients and control subjects to oxidative drug metabolites generated by a murine microsomal system, using a blinded protocol. 3. With human liver microsomes, the metabolism-dependent cytotoxicity of carbamazepine increased with increasing microsomal protein concentration. At a protein concentration of 2 mg per incubation, the cytotoxicity of carbamazepine with human liver microsomes (n = 10 livers) increased from 7.2 +/- 0.8% (baseline) to 16.4 +/- 2.1% (with NADPH; P = 0.002). 4. In the presence of phenobarbitone-induced mouse microsomes and NADPH, the mean increase in cytotoxicity above the baseline with carbamazepine was significantly greater (P less than 0.001) for the cells from the carbamazepine-hypersensitive patients (7.9 +/- 0.8%) than from control subjects (2.6 +/- 0.3%). 5. In the presence of phenobarbitone-induced mouse microsomes and NADPH, there was no significant difference in cytotoxicity between the cells from carbamazepine hypersensitive patients and from control subjects in the presence of either phenytoin or oxcarbazepine.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1768568

Reprogrammed mouse astrocytes retain a "memory" of tissue origin and possess more tendencies for neuronal differentiation than reprogrammed mouse embryonic fibroblasts.

PubMed

Tian, Changhai; Wang, Yongxiang; Sun, Lijun; Ma, Kangmu; Zheng, Jialin C

2011-02-01

Direct reprogramming of a variety of somatic cells with the transcription factors Oct4 (also called Pou5f1), Sox2 with either Klf4 and Myc or Lin28 and Nanog generates the induced pluripotent stem cells (iPSCs) with marker similarity to embryonic stem cells. However, the difference between iPSCs derived from different origins is unclear. In this study, we hypothesized that reprogrammed cells retain a "memory" of their origins and possess additional potential of related tissue differentiation. We reprogrammed primary mouse astrocytes via ectopic retroviral expression of OCT3/4, Sox2, Klf4 and Myc and found the iPSCs from mouse astrocytes expressed stem cell markers and formed teratomas in SCID mice containing derivatives of all three germ layers similar to mouse embryonic stem cells besides semblable morphologies. To test our hypothesis, we compared embryonic bodies (EBs) formation and neuronal differentiation between iPSCs from mouse embryonic fibroblasts (MEFsiPSCs) and iPSCs from mouse astrocytes (mAsiPSCs). We found that mAsiPSCs grew slower and possessed more potential for neuronal differentiation compared to MEFsiPSCs. Our results suggest that mAsiPSCs retain a "memory" of the central nervous system, which confers additional potential upon neuronal differentiation.

Conjugation of tetanus toxoid with Salmonella typhimurium PTCC 1735 O-specific polysaccharide and its effects on production of opsonizing antibodies in a mouse model.

PubMed

Jazani, Nima Hosseini; Worobec, Elizabeth; Shahabi, Shahram; Nejad, Ghorban Behzadian

2005-04-01

Serious enteric and extra-intestinal infections with Salmonella typhimurium are very common in many human populations. Phagocytosis is the main defense mechanism against this bacterium; however, the unique structure of S. typhimurium lipopolysaccharide (LPS) makes it resistant to opsonization by complement components. In the present study, the S. typhimurium LPS O-chain was purified and conjugated with tetanus toxoid and the effects of the conjugated vaccine (O-specific polysaccharide tetanus toxoid (O-SP-TT)) on induction of specific antibodies were investigated in a mouse model. In vitro assays measuring phagocytosis in the presence of opsonizing antibodies were performed. Three subcutaneous injections of the O-SP-TT conjugate conferred protection against the intraperitoneal challenge with S. typhimurium and the LD50 was greater for immunized animals than for controls. The mean number of ingested S. typhimirium / mouse peritoneal cell in the presence of sera obtained from immunized mice with purified O-chain, O-SP-TT conjugate, heat-killed bacteria, and negative control were 6.96, 14.24, 15.96, and 6.67, respectively. In summary, we developed an O-SP-TT conjugate that induced opsonizing antibodies that increased phagocytosis, as determined by in vitro assays. In addition, chemiluminescence results, an indicator of oxidative burst, indicated that peritoneal cells respond better to live S. typhimurium cells in the presence of sera obtained from O-SP-TT conjugate immunized mice.

Long term effects of lipopolysaccharide on satellite glial cells in mouse dorsal root ganglia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blum, E.; Procacci, P.; Conte, V.

Lipopolysaccharide (LPS) has been used extensively to study neuroinflammation, but usually its effects were examined acutely (24 h<). We have shown previously that a single intraperitoneal LPS injection activated satellite glial cells (SGCs) in mouse dorsal root ganglia (DRG) and altered several functional parameters in these cells for at least one week. Here we asked whether the LPS effects would persist for 1 month. We injected mice with a single LPS dose and tested pain behavior, assessed SGCs activation in DRG using glial fibrillary acidic protein (GFAP) immunostaining, and injected a fluorescent dye intracellularly to study intercellular coupling. Electron microscopymore » was used to quantitate changes in gap junctions. We found that at 30 days post-LPS the threshold to mechanical stimulation was lower than in controls. GFAP expression, as well as the magnitude of dye coupling among SGCs were greater than in controls. Electron microscopy analysis supported these results, showing a greater number of gap junctions and an abnormal growth of SGC processes. These changes were significant, but less prominent than at 7 days post-LPS. We conclude that a single LPS injection exerts long-term behavioral and cellular changes. The results are consistent with the idea that SGC activation contributes to hyperalgesia. - Highlights: • A single lipopolysaccharides injection activated glia in mouse dorsal root ganglia for 30 days. • This was accompanied by increased communications by gap junctions among glia and by hyperalgesia. • Glial activation and coupling may contribute to chronic pain.« less

Inhibitors of ORAI1 Prevent Cytosolic Calcium-Associated Injury of Human Pancreatic Acinar Cells and Acute Pancreatitis in 3 Mouse Models

PubMed Central

Wen, Li; Voronina, Svetlana; Javed, Muhammad A.; Awais, Muhammad; Szatmary, Peter; Latawiec, Diane; Chvanov, Michael; Collier, David; Huang, Wei; Barrett, John; Begg, Malcolm; Stauderman, Ken; Roos, Jack; Grigoryev, Sergey; Ramos, Stephanie; Rogers, Evan; Whitten, Jeff; Velicelebi, Gonul; Dunn, Michael; Tepikin, Alexei V.; Criddle, David N.; Sutton, Robert

2015-01-01

Background & Aims Sustained activation of the cytosolic calcium concentration induces injury to pancreatic acinar cells and necrosis. The calcium release–activated calcium modulator ORAI1 is the most abundant Ca2+ entry channel in pancreatic acinar cells; it sustains calcium overload in mice exposed to toxins that induce pancreatitis. We investigated the roles of ORAI1 in pancreatic acinar cell injury and the development of acute pancreatitis in mice. Methods Mouse and human acinar cells, as well as HEK 293 cells transfected to express human ORAI1 with human stromal interaction molecule 1, were hyperstimulated or incubated with human bile acid, thapsigargin, or cyclopiazonic acid to induce calcium entry. GSK-7975A or CM_128 were added to some cells, which were analyzed by confocal and video microscopy and patch clamp recordings. Acute pancreatitis was induced in C57BL/6J mice by ductal injection of taurolithocholic acid 3-sulfate or intravenous' administration of cerulein or ethanol and palmitoleic acid. Some mice then were given GSK-7975A or CM_128, which inhibit ORAI1, at different time points to assess local and systemic effects. Results GSK-7975A and CM_128 each separately inhibited toxin-induced activation of ORAI1 and/or activation of Ca2+ currents after Ca2+ release, in a concentration-dependent manner, in mouse and human pancreatic acinar cells (inhibition >90% of the levels observed in control cells). The ORAI1 inhibitors also prevented activation of the necrotic cell death pathway in mouse and human pancreatic acinar cells. GSK-7975A and CM_128 each inhibited all local and systemic features of acute pancreatitis in all 3 models, in dose- and time-dependent manners. The agents were significantly more effective, in a range of parameters, when given at 1 vs 6 hours after induction of pancreatitis. Conclusions Cytosolic calcium overload, mediated via ORAI1, contributes to the pathogenesis of acute pancreatitis. ORAI1 inhibitors might be developed for the treatment of patients with pancreatitis. PMID:25917787

Mice Expressing RHAG and RHD Human Blood Group Genes

PubMed Central

Goossens, Dominique; da Silva, Nelly; Metral, Sylvain; Cortes, Ulrich; Callebaut, Isabelle; Picot, Julien; Mouro-Chanteloup, Isabelle; Cartron, Jean-Pierre

2013-01-01

Anti-RhD prophylaxis of haemolytic disease of the fetus and newborn (HDFN) is highly effective, but as the suppressive mechanism remains uncertain, a mouse model would be of interest. Here we have generated transgenic mice expressing human RhAG and RhD erythrocyte membrane proteins in the presence and, for human RhAG, in the absence, of mouse Rhag. Human RhAG associates with mouse Rh but not mouse Rhag on red blood cells. In Rhag knockout mice transgenic for human RHAG, the mouse Rh protein is “rescued” (re-expressed), and co-immunoprecipitates with human RhAG, indicating the presence of hetero-complexes which associate mouse and human proteins. RhD antigen was expressed from a human RHD gene on a BAC or from RHD cDNA under control of β-globin regulatory elements. RhD was never observed alone, strongly indicative that its expression absolutely depends on the presence of transgenic human RhAG. This first expression of RhD in mice is an important step in the creation of a mouse model of RhD allo-immunisation and HDFN, in conjunction with the Rh-Rhag knockout mice we have developed previously. PMID:24260394

Effect of PKC412, an inhibitor of protein kinase C, on spontaneous metastatic model mice.

PubMed

Nakamura, Kazuki; Yoshikawa, Noriko; Yamaguchi, Yu; Kagota, Satomi; Shinozuka, Kazumasa; Kunitomo, Masaru

2003-01-01

We investigated the anti-metastatic effect of PKC412, a selective inhibitor of protein kinase C (PKC), on a spontaneous metastatic mouse model, which was prepared by inoculation with B16-BL6 mouse melanoma cells into the footpad of the right hind leg. At two weeks after inoculation, the primary tumor was amputated completely. PKC412 (200 mg/kg) administered orally for four weeks after the tumor inoculation, significantly prolonged survival compared with the control. Furthermore, to elucidate the mechanism of the anti-metastatic effect of PKC412, we examined the growth rate of B16-BL6 cells premixed with Matrigel in vivo and the invasiveness of B16-BL6 cells using a chemo-invasion chamber in vitro. PKC412 significantly reduced the growth rate of cells in vivo (100 and 200 mg/kg) and the invading cells in vitro (10, 30 and 100 nM) in a dose-dependent manner. Thus, PKC412 exerts an anti-metastatic action through inhibition of the invasiveness of melanoma cells in the extracellular matrix.

Induced Pluripotent Stem Cell Technology in Regenerative Medicine and Biology

NASA Astrophysics Data System (ADS)

Pei, Duanqing; Xu, Jianyong; Zhuang, Qiang; Tse, Hung-Fat; Esteban, Miguel A.

The potential of human embryonic stem cells (ESCs) for regenerative medicine is unquestionable, but practical and ethical considerations have hampered clinical application and research. In an attempt to overcome these issues, the conversion of somatic cells into pluripotent stem cells similar to ESCs, commonly termed nuclear reprogramming, has been a top objective of contemporary biology. More than 40 years ago, King, Briggs, and Gurdon pioneered somatic cell nuclear reprogramming in frogs, and in 1981 Evans successfully isolated mouse ESCs. In 1997 Wilmut and collaborators produced the first cloned mammal using nuclear transfer, and then Thomson obtained human ESCs from in vitro fertilized blastocysts in 1998. Over the last 2 decades we have also seen remarkable findings regarding how ESC behavior is controlled, the importance of which should not be underestimated. This knowledge allowed the laboratory of Shinya Yamanaka to overcome brilliantly conceptual and technical barriers in 2006 and generate induced pluripotent stem cells (iPSCs) from mouse fibroblasts by overexpressing defined combinations of ESC-enriched transcription factors. Here, we discuss some important implications of human iPSCs for biology and medicine and also point to possible future directions.

STING activation of tumor endothelial cells initiates spontaneous and therapeutic antitumor immunity.

PubMed

Demaria, Olivier; De Gassart, Aude; Coso, Sanja; Gestermann, Nicolas; Di Domizio, Jeremy; Flatz, Lukas; Gaide, Olivier; Michielin, Olivier; Hwu, Patrick; Petrova, Tatiana V; Martinon, Fabio; Modlin, Robert L; Speiser, Daniel E; Gilliet, Michel

2015-12-15

Spontaneous CD8 T-cell responses occur in growing tumors but are usually poorly effective. Understanding the molecular and cellular mechanisms that drive these responses is of major interest as they could be exploited to generate a more efficacious antitumor immunity. As such, stimulator of IFN genes (STING), an adaptor molecule involved in cytosolic DNA sensing, is required for the induction of antitumor CD8 T responses in mouse models of cancer. Here, we find that enforced activation of STING by intratumoral injection of cyclic dinucleotide GMP-AMP (cGAMP), potently enhanced antitumor CD8 T responses leading to growth control of injected and contralateral tumors in mouse models of melanoma and colon cancer. The ability of cGAMP to trigger antitumor immunity was further enhanced by the blockade of both PD1 and CTLA4. The STING-dependent antitumor immunity, either induced spontaneously in growing tumors or induced by intratumoral cGAMP injection was dependent on type I IFNs produced in the tumor microenvironment. In response to cGAMP injection, both in the mouse melanoma model and an ex vivo model of cultured human melanoma explants, the principal source of type I IFN was not dendritic cells, but instead endothelial cells. Similarly, endothelial cells but not dendritic cells were found to be the principal source of spontaneously induced type I IFNs in growing tumors. These data identify an unexpected role of the tumor vasculature in the initiation of CD8 T-cell antitumor immunity and demonstrate that tumor endothelial cells can be targeted for immunotherapy of melanoma.

Cancer immunotherapy and immunological memory.

PubMed

Murata, Kenji; Tsukahara, Tomohide; Torigoe, Toshihiko

2016-01-01

Human immunological memory is the key distinguishing hallmark of the adaptive immune system and plays an important role in the prevention of morbidity and the severity of infection. The differentiation system of T cell memory has been clarified using mouse models. However, the human T cell memory system has great diversity induced by natural antigens derived from many pathogens and tumor cells throughout life, and profoundly differs from the mouse memory system constructed using artificial antigens and transgenic T cells. We believe that only human studies can elucidate the human immune system. The importance of immunological memory in cancer immunotherapy has been pointed out, and the trafficking properties and long-lasting anti-tumor capacity of memory T cells play a crucial role in the control of malignant tumors. Adoptive cell transfer of less differentiated T cells has consistently demonstrated superior anti-tumor capacity relative to more differentiated T cells. Therefore, a human T cell population with the characteristics of stem cell memory is thought to be attractive for peptide vaccination and adoptive cell transfer. A novel human memory T cell population that we have identified is closer to the naive state than previous memory T cells in the T cell differentiation lineage, and has the characteristics of stem-like chemoresistance. Here we introduce this novel population and describe the fundamentals of immunological memory in cancer immunotherapy.

Local Controlled Release of Polyphenol Conjugated with Gelatin Facilitates Bone Formation

PubMed Central

Honda, Yoshitomo; Tanaka, Tomonari; Tokuda, Tomoko; Kashiwagi, Takahiro; Kaida, Koji; Hieda, Ayato; Umezaki, Yasuyuki; Hashimoto, Yoshiya; Imai, Koichi; Matsumoto, Naoyuki; Baba, Shunsuke; Shimizutani, Kimishige

2015-01-01

Catechins are extensively used in health care treatments. Nevertheless, there is scarce information about the feasibility of local administration with polyphenols for bone regeneration therapy, possibly due to lack of effective delivery systems. Here we demonstrated that the epigallocatechin-3-gallate-conjugated gelatin (EGCG/Gel) prepared by an aqueous chemical synthesis using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-morpholinium chloride (DMT-MM) gradually disintegrated with time and facilitated bone formation in a critical size defect of a mouse calvaria. Conjugation of EGCG with the Gel generated cross-linking between the two molecules, thereby leading to a retardation of the degradation of the EGCG/Gel and to a delayed release of EGCG. The prepared EGCG/Gels represented significant osteogenic capability compared with that of the uncross-linked Gel and the cross-linked Gel with uncombined-EGCG. In vitro experiments disclosed that the EGCG/Gel induced osteoblastogenesis of a mouse mesenchymal stem cell line (D1 cells) within 14 days. Using fluorescently-labeled EGCG/Gel, we found that the fraction of EGCG/Gel adsorbed onto the cell membrane of the D1 cells possibly via a Gel-cell interaction. The interaction might confer the long-term effects of EGCG on the cells, resulting in a potent osteogenic capability of the EGCG/Gel in vivo. These results should provide insight into local controlled release of polyphenols for bone therapy. PMID:26110386

LIS1 controls mitosis and mitotic spindle organization via the LIS1–NDEL1–dynein complex

PubMed Central

Moon, Hyang Mi; Youn, Yong Ha; Pemble, Hayley; Yingling, Jessica; Wittmann, Torsten; Wynshaw-Boris, Anthony

2014-01-01

Heterozygous LIS1 mutations are responsible for the human neuronal migration disorder lissencephaly. Mitotic functions of LIS1 have been suggested from many organisms throughout evolution. However, the cellular functions of LIS1 at distinct intracellular compartments such as the centrosome and the cell cortex have not been well defined especially during mitotic cell division. Here, we used detailed cellular approaches and time-lapse live cell imaging of mitosis from Lis1 mutant mouse embryonic fibroblasts to reveal critical roles of LIS1 in mitotic spindle regulation. We found that LIS1 is required for the tight control of chromosome congression and segregation to dictate kinetochore–microtubule (MT) interactions and anaphase progression. In addition, LIS1 is essential for the establishment of mitotic spindle pole integrity by maintaining normal centrosome number. Moreover, LIS1 plays crucial roles in mitotic spindle orientation by increasing the density of astral MT plus-end movements toward the cell cortex, which enhances cortical targeting of LIS1–dynein complex. Overexpression of NDEL1–dynein and MT stabilization rescues spindle orientation defects in Lis1 mutants, demonstrating that mouse LIS1 acts via the LIS1–NDEL1–dynein complex to regulate astral MT plus-ends dynamics and establish proper contacts of MTs with the cell cortex to ensure precise cell division. PMID:24030547

Effect of 935-MHz phone-simulating electromagnetic radiation on endometrial glandular cells during mouse embryo implantation.

PubMed

Liu, Wenhui; Zheng, Xinmin; Qu, Zaiqing; Zhang, Ming; Zhou, Chun; Ma, Ling; Zhang, Yuanzhen

2012-10-01

This study examined the impact of 935MHz phone-simulating electromagnetic radiation on embryo implantation of pregnant mice. Each 7-week-old Kunming (KM) female white mouse was set up with a KM male mouse in a single cage for mating overnight after induction of ovulation. In the first three days of pregnancy, the pregnant mice was exposed to electromagnetic radiation at low-intensity (150 μW/cm(2), ranging from 130 to 200 μW/cm(2), for 2- or 4-h exposure every day), mid-intensity (570 μW/cm(2), ranging from 400 to 700 μW/cm(2), for 2- or 4-h exposure every day) or high-intensity (1400 μW/cm(2), ranging from 1200 to 1500 μW/cm(2), for 2- or 4-h exposure every day), respectively. On the day 4 after gestation (known as the window of murine embryo implantation), the endometrium was collected and the suspension of endometrial glandular cells was made. Laser scanning microscopy was employed to detect the mitochondrial membrane potential and intracellular calcium ion concentration. In high-intensity, 2- and 4-h groups, mitochondrial membrane potential of endometrial glandular cells was significantly lower than that in the normal control group (P<0.05). The calcium ion concentration was increased in low-intensity 2-h group but decreased in high-intensity 4-h group as compared with the normal control group (P<0.05). However, no significant difference was found in mitochondrial membrane potential of endometrial glandular cells between low- or mid-intensity groups and the normal control group, indicating stronger intensity of the electromagnetic radiation and longer length of the radiation are required to inflict a remarkable functional and structural damage to mitochondrial membrane. Our data demonstrated that electromagnetic radiation with a 935-MHz phone for 4 h conspicuously decreased mitochondrial membrane potential and lowered the calcium ion concentration of endometrial glandular cells. It is suggested that high-intensity electromagnetic radiation is very likely to induce the death of embryonic cells and decrease the chance of their implantation, thereby posing a high risk to pregnancy.

Genotoxicity tests on D-tagatose.

PubMed

Kruger, C L; Whittaker, M H; Frankos, V H

1999-04-01

D-tagatose is a low-calorie sweetener that tastes like sucrose. Its genotoxic potential was examined in five standard assays: the Ames Salmonella typhimurium reverse mutation assay, the Escherichia coli/mammalian microsome assay, a chromosomal aberration assay in Chinese hamster ovary cells, a mouse lymphoma forward mutation assay, and an in vivo mouse micronucleus assay. D-tagatose was not found to increase the number of revertants per plate relative to vehicle controls in either the S. typhimurium tester strains or the WP2uvrA- tester strain with or without metabolic activation at doses up to 5000 microg/plate. No significant increase in Chinese hamster ovary cells with chromosomal aberrations was observed at concentrations up to 5000 microg/ml with or without metabolic activation. D-tagatose was not found to increase the mutant frequency in mouse lymphoma L5178Y cells with or without metabolic activation up to concentrations of 5000 microg/ml. D-tagatose caused no significant increase in micronuclei in bone marrow polychromatic erythrocytes at doses up to 5000 mg/kg. D-tagatose was not found to be genotoxic under the conditions of any of the assays described above. Copyright 1999 Academic Press.

A synergistic interferon-γ production is induced by mouse hepatitis virus in interleukin-12 (IL-12)/IL-18-activated natural killer cells and modulated by carcinoembryonic antigen-related cell adhesion molecules (CEACAM) 1a receptor

PubMed Central

Jacques, Alexandre; Bleau, Christian; Turbide, Claire; Beauchemin, Nicole; Lamontagne, Lucie

2009-01-01

The production of interferon-γ (IFN-γ) by infiltrating natural killer (NK) cells in liver is involved in the control of mouse hepatitis virus (MHV) infection. The objectives of this study were to identify the mechanisms used by MHV type 3 to modulate the production of IFN-γ by NK cells during the acute hepatitis in susceptible C57BL/6 mice. Ex vivo and in vitro experiments revealed that NK cells, expressing carcinoembryonic antigen-related cell adhesion molecules (CEACAM) 1a (the MHV receptor), can produce a higher level of IFN-γ in the presence of both L2-MHV3 and interleukin-12 (IL-12)/IL-18. The synergistic production of IFN-γ by NK cells depends on viral replication rather than viral fixation only, because it is inhibited or not induced in cells infected with ultraviolet-inactivated viruses and in cells from Ceacam1a−/− mice infected with virulent viruses. The synergistic IFN-γ production involves the p38 mitogen-activated protein kinase (MAPK) rather than the extracellular signal-regulated kinase-1/2 MAPK signalling pathway. However, the signal triggered through the engagement of CEACAM1a decreases the production of IFN-γ, when these molecules are cross-linked using specific monoclonal antibodies. These results suggest that control of acute hepatitis by IFN-γ-producing NK cells may depend on both production of IL-12 and IL-18 in the liver environment and viral infection of NK cells. PMID:19740316

[Relationship between sensitivity of tumor cells to chemotherapeutic agent in vivo and in vitro: experiment with mouse lymphoma cells].

PubMed

Li, Chuan-gang; Li, Mo-lin; Shu, Xiao-hong; Jia, Yu-jie; Liu, Yong-ji; Li, Ming

2007-06-12

To study the relationship of the sensitivity of tumor cells to chemotherapeutic agent between in vivo and in vitro. Mouse lymphoma cells of the line E14 were cultured and melphalan resistant EL4 cell line (EL4/melphalan) was established by culturing EL4 cells with continuous low-concentration and intermittent gradually-increasing-concentration of melphalan in vitro. MTT assay was used to evaluate the drug sensitivity and the resistance index of the EL4/melphalan cells to melphalan was calculated. EL4/melphalan and EL4 cells of the concentration of 5 x 10(8)/L were inoculated separately into 20 C57BL/6 mice subcutaneously. 12 days later, the EL4 and EL4/melphalan tumor-bearing mice were randomly divided into 2 groups respectively, 5 mice in each group. Treatment groups were given 7.5 mg/kg melphalan intraperitoneally, and control groups were given the same volume of normal saline. The tumor size was observed every other day. Compared with the EL4 cells, the EL4/melphalan cells had no obvious changes morphologically. They could grow in RPMI 1640 medium containing 5 mg/ml melphalan. The resistance index was 2.87 against melphalan. After the treatment of melphalan of the dose 7.5 mg/kg, the tumor sizes of the treatment groups and control groups inoculated with both EL4 cells and the EL4/melphalan cells gradually decreased at the similar speed, and about one week later all tumors disappeared. However, the tumors of the control groups grew progressively and all the mice died at last. The chemotherapeutic effects of tumors in vivo have nothing to do with the effects of the chemotherapeutic agents on tumor cells in vitro. The tumor cells resistant to melphalan in vitro remain sensitive to the drug in vivo.

Anti-tumor effects of peptide analogs targeting neuropeptide hormone receptors on mouse pheochromocytoma cells.

PubMed

Ziegler, C G; Ullrich, M; Schally, A V; Bergmann, R; Pietzsch, J; Gebauer, L; Gondek, K; Qin, N; Pacak, K; Ehrhart-Bornstein, M; Eisenhofer, G; Bornstein, S R

2013-05-22

Pheochromocytoma is a rare but potentially lethal chromaffin cell tumor with currently no effective treatment. Peptide hormone receptors are frequently overexpressed on endocrine tumor cells and can be specifically targeted by various anti-tumor peptide analogs. The present study carried out on mouse pheochromocytoma cells (MPCs) and a more aggressive mouse tumor tissue-derived (MTT) cell line revealed that these cells are characterized by pronounced expression of the somatostatin receptor 2 (sst2), growth hormone-releasing hormone (GHRH) receptor and the luteinizing hormone-releasing hormone (LHRH) receptor. We further demonstrated significant anti-tumor effects mediated by cytotoxic somatostatin analogs, AN-162 and AN-238, by LHRH antagonist, Cetrorelix, by the cytotoxic LHRH analog, AN-152, and by recently developed GHRH antagonist, MIA-602, on MPC and for AN-152 and MIA-602 on MTT cells. Studies of novel anti-tumor compounds on these mouse cell lines serve as an important basis for mouse models of metastatic pheochromocytoma, which we are currently establishing. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Transcription Factor Foxo1 Is a Negative Regulator of NK Cell Maturation and Function

PubMed Central

Deng, Youcai; Kerdiles, Yann; Chu, Jianhong; Yuan, Shunzong; Wang, Youwei; Chen, Xilin; Mao, Hsiaoyin; Zhang, Lingling; Zhang, Jianying; Hughes, Tiffany; Deng, Yafei; Zhang, Qi; Wang, Fangjie; Zou, Xianghong; Liu, Chang-Gong; Freud, Aharon G.; Li, Xiaohui; Caligiuri, Michael A; Vivier, Eric; Yu, Jianhua

2015-01-01

SUMMARY Little is known about the role of negative regulators in controlling natural killer (NK) cell development and effector functions. Foxo1 is a multifunctional transcription factor of the forkhead family. Using a mouse model of conditional deletion in NK cells, we found that Foxo1 negatively controlled NK cell differentiation and function. Immature NK cells expressed abundant Foxo1 and little Tbx21 relative to mature NK cells, but these two transcription factors reversed their expression as NK cells proceeded through development. Foxo1 promoted NK cell homing to lymph nodes through upregulating CD62L expression, and impaired late-stage maturation and effector functions by repressing Tbx21 expression. Loss of Foxo1 rescued the defect in late-stage NK cell maturation in heterozygous Tbx21+/− mice. Collectively, our data reveal a regulatory pathway by which the negative regulator Foxo1 and the positive regulator Tbx21 play opposing roles in controlling NK cell development and effector functions. PMID:25769609

Lysyl oxidase‑like 2 is expressed in kidney tissue and is associated with the progression of tubulointerstitial fibrosis.

PubMed

Choi, Sung-Eun; Jeon, Nara; Choi, Hoon Young; Shin, Jae Il; Jeong, Hyeon Joo; Lim, Beom Jin

2017-09-01

Tubulointerstitial fibrosis is a common end point of chronic kidney diseases, and preventing its progression is key to avoiding renal failure. Transforming growth factor‑β (TGF‑β) and associated molecules promote tubulointerstitial fibrosis; however, effective therapies targeting these molecules have yet to be developed. Lysyl oxidase‑like 2 (LOXL2), which is involved in invasive growth and metastasis of malignant neoplasms, has recently been reported to serve a key role in hepatic and pulmonary fibrosis. However, little is currently known regarding LOXL2 expression in the kidney and its involvement in tubulointerstitial fibrosis. The present study evaluated LOXL2 expression in human and mouse kidney tissues, as well as in cultured renal cells. LOXL2 protein expression was detected in glomerular capillary loops and tubular epithelial cells in human and mouse kidneys. Glomerular LOXL2 was localized to the cytoplasm of podocytes, as determined by double immunofluorescence microscopy using a podocyte marker (synaptopodin). This result was supported by western blot analysis, which demonstrated that LOXL2 protein expression is present in cultured human podocytes and HK‑2 human proximal tubular cells. In addition, the mRNA and protein expression levels of LOXL2 were higher in a mouse model of tubulointerstitial fibrosis compared with in control mice. In addition, immunohistochemistry results demonstrated that LOXL2 is present in the fibrous interstitium and infiltrating mononuclear cells in a mouse model of tubulointerstitial fibrosis. The present study demonstrated that LOXL2 is expressed in compartments of renal tissue, where it appears to contribute to the progression of tubulointerstitial fibrosis.

Immuno-detection of cleaved SNAP-25 from differentiated mouse embryonic stem cells provides a sensitive assay for determination of botulinum A toxin and antitoxin potency.

PubMed

Yadirgi, G; Stickings, P; Rajagopal, S; Liu, Y; Sesardic, D

2017-12-01

Botulinum toxin type A is a causative agent of human botulism. Due to high toxicity and ease of production it is classified by the Centres for Disease Control and Prevention as a category A bioterrorism agent. The same serotype, BoNT/A, is also the most widely used in pharmaceutical preparations for treatment of a diverse range of neuromuscular disorders. Traditionally, animals are used to confirm the presence and activity of toxin and to establish neutralizing capabilities of countermeasures in toxin neutralization tests. Cell based assays for BoNT/A have been reported as the most viable alternative to animal models, since they are capable of reflecting all key steps (binding, translocation, internalization and cleavage of intracellular substrate) involved in toxin activity. In this paper we report preliminary development of a simple immunochemical method for specifically detecting BoNT/A cleaved intracellular substrate, SNAP-25, in cell lysates of neurons derived from mouse embryonic stem cells. The assay offers sensitivity of better than 0.1LD50/ml (3fM) which is not matched by other functional assays, including the mouse bioassay, and provides serotype specificity for quantitative detection of BoNT/A and anti-BoNT/A antitoxin. Subject to formal validation, the method described here could potentially be used as a substitute for the mouse bioassay to measure potency and consistency of therapeutic products. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Suppressed prostate epithelial development with impaired branching morphogenesis in mice lacking stromal fibromuscular androgen receptor.

PubMed

Lai, Kuo-Pao; Yamashita, Shinichi; Vitkus, Spencer; Shyr, Chih-Rong; Yeh, Shuyuan; Chang, Chawnshang

2012-01-01

Using the cre-loxP system, we generated a new mouse model [double stromal androgen receptor knockout (dARKO)] with selectively deleted androgen receptor (AR) in both stromal fibroblasts and smooth muscle cells, and found the size of the anterior prostate (AP) lobes was significantly reduced as compared with those from wild-type littermate controls. The reduction in prostate size of the dARKO mouse was accompanied by impaired branching morphogenesis and partial loss of the infolding glandular structure. Further dissection found decreased proliferation and increased apoptosis of the prostate epithelium in the dARKO mouse AP. These phenotype changes were further confirmed with newly established immortalized prostate stromal cells (PrSC) from wild-type and dARKO mice. Mechanistically, IGF-1, placental growth factor, and secreted phosphoprotein-1 controlled by stromal AR were differentially expressed in PrSC-wt and PrSC-ARKO. Moreover, the conditioned media (CM) from PrSC-wt promoted prostate epithelium growth significantly as compared with CM from PrSC-dARKO. Finally, adding IGF-1/placental growth factor recombinant proteins into PrSC-dARKO CM was able to partially rescue epithelium growth. Together, our data concluded that stromal fibromuscular AR could modulate epithelium growth and maintain cellular homeostasis through identified growth factors.

[Effects of intrasplenic transplantation of IL-18 gene-modified fetal hepatocytes on mouse immune function

PubMed

Yao, Hang-Ping; Zhang, Li-Huang; Sun, Wen-Ji; Leng, Jian-Hang

2002-04-01

OBJECTIVE: To investigate the effects of IL-18 gene-modified fetal hepatocytes (AdmIL-18/MNL.CL2) intrasplenic transplantation on mouse immune function. METHODS: Forty mice were evenly divided into 4 groups of 10. Each group received an intrasplenic transplantation one of the following: AdmIL-18/BNL.CL2, Ad-LacZ/BNL.CL2 (virus control), BNL.CL2 (cell control) and PBS (blank control). After two weeks, the mice were sacrificed. Serum cytokine levels, Mpsi and splenic cell culture supernatant and liver tissue extracts supernatants were measured using ELISA. Hepatic cytokines mRNA expression were determined by RT-PCR. THe cytotoxicity of peritoneal Mpsi and NK activity of spienocytes were detected by LDH release assay. The proliferation of splenic lymphocytes was determined by MTT assay. RESULTS: The IL-18, IL-2,IFN-gamma, TNF-alpha levels of serum, Mpsi and splenocyte culture supernatant, liver tissue extracts supernatants in mice transplanted with AdmIL-18/BNL.CL2 were higher and the IL-4, IL-10 levels were lower compared to their levels in other 3 groups. The highest IL-18, IL-2, IFN-gamma, TNF-alpha and the lowest IL-4, IL-10 mRNA expressions in the liver were observed in mice transplanted with AdmIL-18/BNL.CL2. The mice transplanted with AdmIL-18/BNL.Cl2 showed significantly increases cytotoxicity of Mpsi, NK activity and splenic cell proliferation compared with the other 3 groups. CONCLUSION: AdmIL-18 can be effectively transfected into mice fetal heptocytes which subsequently IL-18. Intransplenic transplantation of IL-18 gene-modified fetal hepatocytes may augment mouse immune function and provide an useful basis for targeted gene therapy of liver disease.

Cytogenetic effects of sildenafil citrate (Viagra) on SWR/J mouse bone marrow cells

PubMed Central

Abou-Tarboush, Faisal Mohamed; Abdel-Samad, Mohamed Fathy

2010-01-01

The present study was conducted to investigate the cytogenetic effects of sildenafil citrate in SWR/J mouse bone marrow cells. Thirty-six males and 36 females were used and divided into four groups. Each group contained 18 animals (9 males and 9 females), weighing 30–35 g. These animals were orally administered with a single dose of 13, 26 or 40 mg/kg sildenafil citrate solution. A control group received normal saline in an identical condition. The animals were sacrificed at 12, 24 or 48 h, after the treatment. Chromosome aberrations were investigated in 50 metaphases per animal. No significant differences in the percentages of mitotic indices or in the frequencies of chromosome aberrations were observed between treated male and female mice at any doses or at any time intervals used, therefore, data from the two sexes were pooled when analyzed statistically. No significant (p < 0.05) differences in the percentages of mitotic indices or in the frequencies of chromosome aberrations were observed between sildenafil citrate-treated groups and the control group at any doses or at any time intervals used. However, the percentages of centromeric adhesions increased significantly (p < 0.01) in treated groups as compared with the control group at all doses and at all time intervals used. In conclusion, the results of the present study suggest that sildenafil citrate does not have cytogenetic effects on mouse bone marrow cells, but the centromeric adhesions induced by this drug need further studies to confirm them and to investigate the possible mechanism(s) responsible for such effect. PMID:23961094

p53-dependent programmed necrosis controls germ cell homeostasis during spermatogenesis.

PubMed

Napoletano, Francesco; Gibert, Benjamin; Yacobi-Sharon, Keren; Vincent, Stéphane; Favrot, Clémentine; Mehlen, Patrick; Girard, Victor; Teil, Margaux; Chatelain, Gilles; Walter, Ludivine; Arama, Eli; Mollereau, Bertrand

2017-09-01

The importance of regulated necrosis in pathologies such as cerebral stroke and myocardial infarction is now fully recognized. However, the physiological relevance of regulated necrosis remains unclear. Here, we report a conserved role for p53 in regulating necrosis in Drosophila and mammalian spermatogenesis. We found that Drosophila p53 is required for the programmed necrosis that occurs spontaneously in mitotic germ cells during spermatogenesis. This form of necrosis involved an atypical function of the initiator caspase Dronc/Caspase 9, independent of its catalytic activity. Prevention of p53-dependent necrosis resulted in testicular hyperplasia, which was reversed by restoring necrosis in spermatogonia. In mouse testes, p53 was required for heat-induced germ cell necrosis, indicating that regulation of necrosis is a primordial function of p53 conserved from invertebrates to vertebrates. Drosophila and mouse spermatogenesis will thus be useful models to identify inducers of necrosis to treat cancers that are refractory to apoptosis.

Functional conservation of atonal and Math1 in the CNS and PNS

NASA Technical Reports Server (NTRS)

Ben-Arie, N.; Hassan, B. A.; Bermingham, N. A.; Malicki, D. M.; Armstrong, D.; Matzuk, M.; Bellen, H. J.; Zoghbi, H. Y.

2000-01-01

To determine the extent to which atonal and its mouse homolog Math1 exhibit functional conservation, we inserted (beta)-galactosidase (lacZ) into the Math1 locus and analyzed its expression, evaluated consequences of loss of Math1 function, and expressed Math1 in atonal mutant flies. lacZ under the control of Math1 regulatory elements duplicated the previously known expression pattern of Math1 in the CNS (i.e., the neural tube, dorsal spinal cord, brainstem, and cerebellar external granule neurons) but also revealed new sites of expression: PNS mechanoreceptors (inner ear hair cells and Merkel cells) and articular chondrocytes. Expressing Math1 induced ectopic chordotonal organs (CHOs) in wild-type flies and partially rescued CHO loss in atonal mutant embryos. These data demonstrate that both the mouse and fly homologs encode lineage identity information and, more interestingly, that some of the cells dependent on this information serve similar mechanoreceptor functions.

New mouse tumor model system (RIF-1) for comparison of end-point studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Twentyman, P.R.; Brown, J.M.; Gray, J.W.

1980-03-01

A new tumor model system (RIF-1) was developed that is very suitable for studies in which clonogenic survival is compared with growth delay and control probability following various forms of treatment. The tumor was a radiation-induced sarcoma in the inbred female C3H/Km mouse. It had a low median tumor dose, had a satisfactory plating efficiency direct from in vivo to in vitro, was nonimmunogenic or minimally immunogenic, and metastasized only at a relatively advanced stage of growth. The cell line grew either as a monolayer on plastic dishes, as tumor spheroids in spinner culture, as lung nodules following injection ofmore » a single-cell suspension into the tall veins of syngeneic mice, or as a solid tumor. Both diploid and tetraploid clonogenic cells were found in monolayer cultures of the RIF-1 line.« less

Chondroitin Sulfate Is Indispensable for Pluripotency and Differentiation of Mouse Embryonic Stem Cells

NASA Astrophysics Data System (ADS)

Izumikawa, Tomomi; Sato, Ban; Kitagawa, Hiroshi

2014-01-01

Chondroitin sulfate (CS) proteoglycans are present on the surfaces of virtually all cells and in the extracellular matrix and are required for cytokinesis at early developmental stages. Studies have shown that heparan sulfate (HS) is essential for maintaining mouse embryonic stem cells (ESCs) that are primed for differentiation, whereas the function of CS has not yet been elucidated. To clarify the role of CS, we generated glucuronyltransferase-I-knockout ESCs lacking CS. We found that CS was required to maintain the pluripotency of ESCs and promoted initial ESC commitment to differentiation compared with HS. In addition, CS-A and CS-E polysaccharides, but not CS-C polysaccharides, bound to E-cadherin and enhanced ESC differentiation. Multiple-lineage differentiation was inhibited in chondroitinase ABC-digested wild-type ESCs. Collectively, these results suggest that CS is a novel determinant in controlling the functional integrity of ESCs via binding to E-cadherin.

Effect of Short-Term Hypergravity Treatment on Mouse 2-Cell Embryo Development

NASA Astrophysics Data System (ADS)

Ning, Li-Na; Lei, Xiao-Hua; Cao, Yu-Jing; Zhang, Yun-Fang; Cao, Zhong-Hong; Chen, Qi; Duan, En-Kui

2015-11-01

Though there are numerous biological experiments, which have been performed in a space environment, to study the physiological effect of space travel on living organisms, while the potential effect of weightlessness or short-term hypergravity on the reproductive system in most species, particularly in mammalian is still controversial and unclear. In our previous study, we investigated the effect of space microgravity on the development of mouse 4-cell embryos by using Chinese SJ-8. .Unexpectedly, we did not get any developed embryo during the space-flight. Considering that the process of space experiment is quite different from most experiments done on earth in several aspects such as, the vibration and short-term hypergravity during the rock launching and landing. Thus we want to know whether the short-term hypergravity produced by the launch process affect the early embryo development in mice, and howthe early embryos respond to the hypergravity. In present study, we are mimicking the short-term hypergravity during launch by using a centrifuge to investigate its influence on the development of early embryo (2-cell) in mice. We also examined the actin filament distribution in 2-cell embryos by immunostaining to test their potential capacity of development under short-term hypergravity exposure. Our results showed that most 2-cell embryos in the hypergravity exposure groups developed into blastocysts with normal morphology after 72h cultured in vitro, and there is no obvious difference in the development rate of blastocyst formation compared to the control. Moreover, there were no statistically significant differences in birth rates after oviduct transfer of 2-cell mouse embryos exposed on short-term hypergravity compared with 1 g condition. In addition, the well-organized actin distribution appeared in 2-cell embryos after exposed on hypergravity and also in the subsequent developmental blastocysts. Taken together, our data shows that short-term exposure in hypergravity conditions does not affect the normal development and actin filament structures of mouse embryos.

Extract of Ginkgo biloba exacerbates liver metastasis in a mouse colon cancer Xenograft model.

PubMed

Wang, Huan; Wu, Xia; Lezmi, Stephane; Li, Qian; Helferich, William G; Xu, Yueqing; Chen, Hong

2017-12-02

Metastasis refers to the spread of a primary tumor cell from the primary site to other locations in the body and it is generally associated with the severity of a tumor. Extract of Ginkgo biloba (EGb) contains various bioactive compounds and it exerts beneficial effects including improvements in brain function and reduced risk of cardiovascular diseases. On the other hand, increased risk of thyroid and liver cancers by EGb have been reported in animals. A colon cancer metastasis model was established using intrasplenic injection of a human colon cancer cell line, SW620-luc in athymic mice to investigate the potential impact of EGb on colon cancer progression. After tumor establishment, EGb was intraperitonically injected daily for 5 wks. EGb significantly increased the rate of metastasis in mouse liver and decreased the number of necrotic and apoptotic cells in the metastatic liver when compared to the control. Meanwhile, EGb significantly induced proliferation of tumor cells in the metastatic liver, indicated by increased staining of Ki67 and H3S10p. mRNA expression of genes involved in cell cycle, metastasis, apoptosis, and oxidative stress were altered by EGb treatment in livers with tumors. Moreover, EGb activated the stress-responsive MAPK pathways in the liver with metastatic tumors. EGb exacerbated liver metastasis in a mouse colon cancer metastasis model. This is potentially due to the increased tumor cell proliferation involving stimulated MAPK pathways.

Megakaryocyte polyploidization is associated with decreased expression of polo-like kinase (PLK).

PubMed

Yagi, M; Roth, G J

2006-09-01

During differentiation, megakaryocytes (MK), the bone marrow precursors of circulating blood platelets, undergo polyploidization, repeated rounds of DNA replication without cell division. Mature normal MK may contain a DNA content of up to 128N, in contrast to normal diploid (2N) cells. The extent of polyploidy may influence the number of platelets produced by the MK. Therefore, understanding the molecular mechanisms regulating polyploidization could identify events involved in controlling both cell division and thrombopoiesis. We investigated the expression of several proteins involved in mitosis in cultured mouse MK, and tested the effect of expression on polyploidization. Western blot and immunofluorescent analyses were used to assess expression of cell cycle proteins in cultured MK. Populations of polyploidizing MK were separated on the basis of DNA content by flow cytometry. The gene encoding mouse polo-like kinase 1 (PLK-1) was introduced into MK by retroviral transduction, and its effects measured by flow cytometry. Polyploid mouse MK expressed lower levels of two proteins, p55CDC and PLK-1, whose activity is necessary for cell cycle progression and completion of mitosis. Comparison of sorted 2N/4N and polyploid MK indicated that PLK-1 expression was absent in polyploid MK, while expression of other cell cycle proteins was similar in both populations. Forced expression of PLK-1 during MK differentiation was associated with decreased polyploidization. These experiments suggest that PLK-1 is an important regulator of polyploidization in differentiating MK.

Fluorescence lifetime imaging of induced pluripotent stem cells

NASA Astrophysics Data System (ADS)

Uchugonova, Aisada; Batista, Ana; König, Karsten

2014-02-01

The multiphoton FLIM tomograph MPTflex with its flexible scan head, articulated arm, and the tunable femtosecond laser source was employed to study cell monolayers and 3D cell clusters. FLIM was performed with 250 ps temporal resolution and submicron special resolution using time-correlated single photon counting. The autofluorescence based on NAD(P)H and flavins/flavoproteins has been measured in mouse embryonic fibroblasts, induced pluripotent stem cells (iPS cells) originated from mouse embryonic fibroblasts and non-proliferative mouse embryonic fibroblasts.

Pre-crisis mouse cells show strain-specific covariation in the amount of 54-kilodalton phosphoprotein and in susceptibility to transformation by simian virus 40.

PubMed

Chen, S; Blanck, G; Pollack, R E

1983-09-01

We have used several inbred mouse strains to examine the role of the 54-kilodalton (kDa) cellular phosphoprotein in transformation by the papovavirus simian virus 40. We have measured the endogenous 54-kDa phosphoprotein in cells obtained from these inbred mouse strains. To study the effect of passage, cell cultures were measured for amount of the 54-kDa phosphoprotein at the 2nd and 12th passages. In the absence of any transforming agent, the amount of endogenous 54-kDa phosphoprotein in early pre-crisis mouse cells varied in a strain-specific way. Transformation frequency varied coordinately with endogenous 54-kDa expression. Mouse strains whose cells produced a high level of endogenous 54-kDa phosphoprotein on passage did not further increase its expression after simian virus 40 transformation.

Pre-crisis mouse cells show strain-specific covariation in the amount of 54-kilodalton phosphoprotein and in susceptibility to transformation by simian virus 40.

PubMed Central

Chen, S; Blanck, G; Pollack, R E

1983-01-01

We have used several inbred mouse strains to examine the role of the 54-kilodalton (kDa) cellular phosphoprotein in transformation by the papovavirus simian virus 40. We have measured the endogenous 54-kDa phosphoprotein in cells obtained from these inbred mouse strains. To study the effect of passage, cell cultures were measured for amount of the 54-kDa phosphoprotein at the 2nd and 12th passages. In the absence of any transforming agent, the amount of endogenous 54-kDa phosphoprotein in early pre-crisis mouse cells varied in a strain-specific way. Transformation frequency varied coordinately with endogenous 54-kDa expression. Mouse strains whose cells produced a high level of endogenous 54-kDa phosphoprotein on passage did not further increase its expression after simian virus 40 transformation. Images PMID:6310588

Practical use of advanced mouse models for lung cancer.

PubMed

Safari, Roghaiyeh; Meuwissen, Ralph

2015-01-01

To date a variety of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) mouse models have been developed that mimic human lung cancer. Chemically induced or spontaneous lung cancer in susceptible inbred strains has been widely used, but the more recent genetically engineered somatic mouse models recapitulate much better the genotype-phenotype correlations found in human lung cancer. Additionally, improved orthotopic transplantation of primary human cancer tissue fragments or cells into lungs of immune-compromised mice can be valuable tools for preclinical research such as antitumor drug tests. Here we give a short overview of most somatic mouse models for lung cancer that are currently in use. We accompany each different model with a description of its practical use and application for all major lung tumor types, as well as the intratracheal injection or direct injection of fresh or freeze-thawed tumor cells or tumor cell lines into lung parenchyma of recipient mice. All here presented somatic mouse models are based on the ability to (in) activate specific alleles at a time, and in a tissue-specific cell type, of choice. This spatial-temporal controlled induction of genetic lesions allows the selective introduction of main genetic lesions in an adult mouse lung as found in human lung cancer. The resulting conditional somatic mouse models can be used as versatile powerful tools in basic lung cancer research and preclinical translational studies alike. These distinctively advanced lung cancer models permit us to investigate initiation (cell of origin) and progression of lung cancer, along with response and resistance to drug therapy. Cre/lox or FLP/frt recombinase-mediated methods are now well-used techniques to develop tissue-restricted lung cancer in mice with tumor-suppressor gene and/or oncogene (in)activation. Intranasal or intratracheal administration of engineered adenovirus-Cre or lentivirus-Cre has been optimized for introducing Cre recombinase activity into pulmonary tissues, and we discuss here the different techniques underlying these applications. Concomitant with Cre/Flp recombinase-based models are the tetracycline (Tet)-inducible bitransgenic systems in which presence or absence of doxycycline can turn the expression of a specific oncogene on or off. The use of several Tet-inducible lung cancer models for NSCLC is presented here in which the reversal of oncogene expression led to complete tumor regression and provided us with important insight of how oncogene dependence influence lung cancer survival and growth. As alternative to Tet-inducible models, we discuss the application of reversible expressed, transgenic mutant estrogen receptor (ER) fusion proteins, which are regulated via systemic tamoxifen administration. Most of the various lung cancer models can be combined through the generation of transgenic compound mice so that the use of these somatic mouse models can be even more enhanced for the study of specific molecular pathways that facilitate growth and maintenance of lung cancer. Finally, this description of the practical application and methodology of mouse models for lung cancer should be helpful in assisting researchers to make the best choices and optimal use of (existing) somatic models that suits the specific experimental needs in their study of lung cancer.

Altered expression of IL-18 binding protein and IL-18 receptor in basophils and mast cells of asthma patients.

PubMed

Wang, Zhiyun; Liu, Zhining; Wang, Ling; Wang, Junling; Chen, Liping; Xie, Hua; Zhang, Huiyun; He, Shaoheng

2018-05-01

IL-18 is likely to contribute to asthma. However, little is known regarding the role of IL-18 binding protein (BP) and IL-18 receptor (R) in asthma. Because the action of IL-18 in the body is regulated by IL-18BP and mast cells and basophils are key cell types involved in asthma, we investigated the expression of IL-18, IL-18BP and IL-18R in basophils and mast cells using flow cytometry and a mouse asthma model. We found that among basophils, approximately 53% and 51% were IL-18 + , 85% and 81% were IL-18BP + basophils, and 19.8% and 8.6% were IL-18R + in healthy control (HC) and asthmatic blood, respectively. The allergens tested had little effect on the expression of IL-18 and related factors. Only 3.5%, 14.3% and 2.4% of dispersed mast cells expressed IL-18, IL-18BP and IL-18R, respectively, in asthmatic sputum. In a mouse asthma model, OVA-sensitized mice exhibited decreased IL-18BP + but increased IL-18R + basophils in their blood. IL-18 increased the number of basophils but eliminated IL-18BP + basophils in mouse blood. IL-18 increased the number of mast cells and IL-18R + mast cells in the lung as well as increased the mast cell numbers and IL-18BP + mast cells in the bronchoalveolar lavage fluid (BALF) of OVA-sensitized mice. Thus, basophils and mast cells may be involved in asthma pathogenesis via an IL-18-associated mechanism. © 2018 The Foundation for the Scandinavian Journal of Immunology.

DACH1 regulates cell cycle progression of myeloid cells through the control of cyclin D, Cdk 4/6 and p21{sup Cip1}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jae-Woong; Kim, Hyeng-Soo; Kim, Seonggon

2012-03-30

Highlights: Black-Right-Pointing-Pointer DACH1 increases cyclin D, F and Cdk 1, 4, 6 in mouse myeloid progenitor cells. Black-Right-Pointing-Pointer The knockdown of DACH1 blocked the cell cycle progression of HL-60 cells. Black-Right-Pointing-Pointer The novel effect of DACH1 related with cell cycle regulation and leukemogenesis. -- Abstract: The cell-fate determination factor Dachshund, a component of the Retinal Determination Gene Network (RDGN), has a role in breast tumor proliferation through the repression of cyclin D1 and several key regulators of embryonic stem cell function, such as Nanog and Sox2. However, little is known about the role of DACH1 in a myeloid lineage asmore » a cell cycle regulator. Here, we identified the differential expression levels of extensive cell cycle regulators controlled by DACH1 in myeloid progenitor cells. The forced expression of DACH1 induced p27{sup Kip1} and repressed p21{sup Cip1}, which is a pivotal characteristic of the myeloid progenitor. Furthermore, DACH1 significantly increased the expression of cyclin D1, D3, F, and Cdk 1, 4, and 6 in myeloid progenitor cells. The knockdown of DACH1 blocked the cell cycle progression of HL-60 promyeloblastic cells through the decrease of cyclin D1, D3, F, and Cdk 1, 4, and 6 and increase in p21{sup Cip1}, which in turn decreased the phosphorylation of the Rb protein. The expression of Sox2, Oct4, and Klf4 was significantly up-regulated by the forced expression of DACH1 in mouse myeloid progenitor cells.« less

The VP40 protein of Marburg virus exhibits impaired budding and increased sensitivity to human tetherin following mouse adaptation.

PubMed

Feagins, Alicia R; Basler, Christopher F

2014-12-01

The Marburg virus VP40 protein is a viral matrix protein that spontaneously buds from cells. It also functions as an interferon (IFN) signaling antagonist by targeting Janus kinase 1 (JAK1). A previous study demonstrated that the VP40 protein of the Ravn strain of Marburg virus (Ravn virus [RAVV]) failed to block IFN signaling in mouse cells, whereas the mouse-adapted RAVV (maRAVV) VP40 acquired the ability to inhibit IFN responses in mouse cells. The increased IFN antagonist function of maRAVV VP40 mapped to residues 57 and 165, which were mutated during the mouse adaptation process. In the present study, we demonstrate that maRAVV VP40 lost the capacity to efficiently bud from human cell lines, despite the fact that both parental and maRAVV VP40s bud efficiently from mouse cell lines. The impaired budding in human cells corresponds with the appearance of protrusions on the surface of maRAVV VP40-expressing Huh7 cells and with an increased sensitivity of maRAVV VP40 to restriction by human tetherin but not mouse tetherin. However, transfer of the human tetherin cytoplasmic tail to mouse tetherin restored restriction of maRAVV VP40. Residues 57 and 165 were demonstrated to contribute to the failure of maRAVV VP40 to bud from human cells, and residue 57 was demonstrated to alter VP40 oligomerization, as assessed by coprecipitation assay, and to determine sensitivity to human tetherin. This suggests that RAVV VP40 acquired, during adaptation to mice, changes in its oligomerization potential that enhanced IFN antagonist function. However, this new capacity impaired RAVV VP40 budding from human cells. Filoviruses, which include Marburg viruses and Ebola viruses, are zoonotic pathogens that cause severe disease in humans and nonhuman primates but do not cause similar disease in wild-type laboratory strains of mice unless first adapted to these animals. Although mouse adaptation has been used as a method to develop small animal models of pathogenesis, the molecular determinants associated with filovirus mouse adaptation are poorly understood. Our study demonstrates how genetic changes that accrued during mouse adaptation of the Ravn strain of Marburg virus have impacted the budding function of the viral VP40 matrix protein. Strikingly, we find impairment of mouse-adapted VP40 budding function in human but not mouse cell lines, and we correlate the impairment with an increased sensitivity of VP40 to restriction by human but not mouse tetherin and with changes in VP40 oligomerization. These data suggest that there are functional costs associated with filovirus adaptation to new hosts and implicate tetherin as a filovirus host restriction factor. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Control of glioblastoma tumorigenesis by feed-forward cytokine signaling

PubMed Central

Jahani-Asl, Arezu; Yin, Hang; Soleimani, Vahab D; Haque, Takrima; Luchman, H Artee; Chang, Natasha C; Sincennes, Marie-Claude; Puram, Sidharth V; Scott, Andrew M; Lorimer, Ian A J; Perkins, Theodore J; Ligon, Keith L; Weiss, Samuel; Rudnicki, Michael A; Bonni, Azad

2016-01-01

EGFRvIII-STAT3 signaling is important in glioblastoma pathogenesis. Here, we identified the cytokine receptor OSMR as a direct target gene of the transcription factor STAT3 in mouse astrocytes and human brain tumor stem cells (BTSCs). We found that OSMR functioned as an essential co-receptor for EGFRvIII. OSMR formed a physical complex with EGFRvIII, and depletion of OSMR impaired EGFRvIII-STAT3 signaling. Conversely, pharmacological inhibition of EGFRvIII phosphorylation inhibited the EGFRvIII-OSMR interaction and activation of STAT3. EGFRvIII-OSMR signaling in tumors operated constitutively, whereas EGFR-OSMR signaling in nontumor cells was synergistically activated by the ligands EGF and OSM. Finally, knockdown of OSMR strongly suppressed cell proliferation and tumor growth of mouse glioblastoma cells and human BTSC xenografts in mice, and prolonged the lifespan of those mice. Our findings identify OSMR as a critical regulator of glioblastoma tumor growth that orchestrates a feed-forward signaling mechanism with EGFRvIII and STAT3 to drive tumorigenesis. PMID:27110918

Targeting neuronal gap junctions in mouse retina offers neuroprotection in glaucoma

PubMed Central

Kumar, Sandeep; Ramakrishnan, Hariharasubramanian; Roy, Kaushambi; Viswanathan, Suresh; Bloomfield, Stewart A.

2017-01-01

The progressive death of retinal ganglion cells and resulting visual deficits are hallmarks of glaucoma, but the underlying mechanisms remain unclear. In many neurodegenerative diseases, cell death induced by primary insult is followed by a wave of secondary loss. Gap junctions (GJs), intercellular channels composed of subunit connexins, can play a major role in secondary cell death by forming conduits through which toxic molecules from dying cells pass to and injure coupled neighbors. Here we have shown that pharmacological blockade of GJs or genetic ablation of connexin 36 (Cx36) subunits, which are highly expressed by retinal neurons, markedly reduced loss of neurons and optic nerve axons in a mouse model of glaucoma. Further, functional parameters that are negatively affected in glaucoma, including the electroretinogram, visual evoked potential, visual spatial acuity, and contrast sensitivity, were maintained at control levels when Cx36 was ablated. Neuronal GJs may thus represent potential therapeutic targets to prevent the progressive neurodegeneration and visual impairment associated with glaucoma. PMID:28604388

Molecular mechanisms and functions of pyroptosis, inflammatory caspases and inflammasomes in infectious diseases.

PubMed

Man, Si Ming; Karki, Rajendra; Kanneganti, Thirumala-Devi

2017-05-01

Cell death is a fundamental biological phenomenon that is essential for the survival and development of an organism. Emerging evidence also indicates that cell death contributes to immune defense against infectious diseases. Pyroptosis is a form of inflammatory programmed cell death pathway activated by human and mouse caspase-1, human caspase-4 and caspase-5, or mouse caspase-11. These inflammatory caspases are used by the host to control bacterial, viral, fungal, or protozoan pathogens. Pyroptosis requires cleavage and activation of the pore-forming effector protein gasdermin D by inflammatory caspases. Physical rupture of the cell causes release of the pro-inflammatory cytokines IL-1β and IL-18, alarmins and endogenous danger-associated molecular patterns, signifying the inflammatory potential of pyroptosis. Here, we describe the central role of inflammatory caspases and pyroptosis in mediating immunity to infection and clearance of pathogens. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

CBX7 gene expression plays a negative role in adipocyte cell growth and differentiation

PubMed Central

Forzati, Floriana; Federico, Antonella; Pallante, Pierlorenzo; Colamaio, Marianna; Esposito, Francesco; Sepe, Romina; Gargiulo, Sara; Luciano, Antonio; Arra, Claudio; Palma, Giuseppe; Bon, Giulia; Bucher, Stefania; Falcioni, Rita; Brunetti, Arturo; Battista, Sabrina; Fedele, Monica; Fusco, Alfredo

2014-01-01

ABSTRACT We have recently generated knockout mice for the Cbx7 gene, coding for a polycomb group protein that is downregulated in human malignant neoplasias. These mice develop liver and lung adenomas and carcinomas, which confirms a tumour suppressor role for CBX7. The CBX7 ability to downregulate CCNE1 expression likely accounts for the phenotype of the Cbx7-null mice. Unexpectedly, Cbx7-knockout mice had a higher fat tissue mass than wild-type, suggesting a role of CBX7 in adipogenesis. Consistently, we demonstrate that Cbx7-null mouse embryonic fibroblasts go towards adipocyte differentiation more efficiently than their wild-type counterparts, and this effect is Cbx7 dose-dependent. Similar results were obtained when Cbx7-null embryonic stem cells were induced to differentiate into adipocytes. Conversely, mouse embryonic fibroblasts and human adipose-derived stem cells overexpressing CBX7 show an opposite behaviour. These findings support a negative role of CBX7 in the control of adipocyte cell growth and differentiation. PMID:25190058

Cryo-imaging of fluorescently labeled single cells in a mouse

NASA Astrophysics Data System (ADS)

Steyer, Grant J.; Roy, Debashish; Salvado, Olivier; Stone, Meredith E.; Wilson, David L.

2009-02-01

We developed a cryo-imaging system to provide single-cell detection of fluorescently labeled cells in mouse, with particular applicability to stem cells and metastatic cancer. The Case cryoimaging system consists of a fluorescence microscope, robotic imaging positioner, customized cryostat, PC-based control system, and visualization/analysis software. The system alternates between sectioning (10-40 μm) and imaging, collecting color brightfield and fluorescent blockface image volumes >60GB. In mouse experiments, we imaged quantum-dot labeled stem cells, GFP-labeled cancer and stem cells, and cell-size fluorescent microspheres. To remove subsurface fluorescence, we used a simplified model of light-tissue interaction whereby the next image was scaled, blurred, and subtracted from the current image. We estimated scaling and blurring parameters by minimizing entropy of subtracted images. Tissue specific attenuation parameters were found [uT : heart (267 +/- 47.6 μm), liver (218 +/- 27.1 μm), brain (161 +/- 27.4 μm)] to be within the range of estimates in the literature. "Next image" processing removed subsurface fluorescence equally well across multiple tissues (brain, kidney, liver, adipose tissue, etc.), and analysis of 200 microsphere images in the brain gave 97+/-2% reduction of subsurface fluorescence. Fluorescent signals were determined to arise from single cells based upon geometric and integrated intensity measurements. Next image processing greatly improved axial resolution, enabled high quality 3D volume renderings, and improved enumeration of single cells with connected component analysis by up to 24%. Analysis of image volumes identified metastatic cancer sites, found homing of stem cells to injury sites, and showed microsphere distribution correlated with blood flow patterns. We developed and evaluated cryo-imaging to provide single-cell detection of fluorescently labeled cells in mouse. Our cryo-imaging system provides extreme (>60GB), micron-scale, fluorescence, and bright field image data. Here we describe our image preprocessing, analysis, and visualization techniques. Processing improves axial resolution, reduces subsurface fluorescence by 97%, and enables single cell detection and counting. High quality 3D volume renderings enable us to evaluate cell distribution patterns. Applications include the myriad of biomedical experiments using fluorescent reporter gene and exogenous fluorophore labeling of cells in applications such as stem cell regenerative medicine, cancer, tissue engineering, etc.

Gut-derived factors promote neurogenesis of CNS-neural stem cells and nudge their differentiation to an enteric-like neuronal phenotype.

PubMed

Kulkarni, Subhash; Zou, Bende; Hanson, Jesse; Micci, Maria-Adelaide; Tiwari, Gunjan; Becker, Laren; Kaiser, Martin; Xie, Xinmin Simon; Pasricha, Pankaj Jay

2011-10-01

Recent studies have explored the potential of central nervous system-derived neural stem cells (CNS-NSC) to repopulate the enteric nervous system. However, the exact phenotypic fate of gut-transplanted CNS-NSC has not been characterized. The aim of this study was to investigate the effect of the gut microenvironment on phenotypic fate of CNS-NSC in vitro. With the use of Transwell culture, differentiation of mouse embryonic CNS-NSC was studied when cocultured without direct contact with mouse intestinal longitudinal muscle-myenteric plexus preparations (LM-MP) compared with control noncocultured cells, in a differentiating medium. Differentiated cells were analyzed by immunocytochemistry and quantitative RT-PCR to assess the expression of specific markers and by whole cell patch-clamp studies for functional characterization of their phenotype. We found that LM-MP cocultured cells had a significant increase in the numbers of cells that were immune reactive against the panneuronal marker β-tubulin, neurotransmitters neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), and neuropeptide vasoactive intestinal peptide (VIP) and showed an increase in expression of these genes, compared with control cells. Whole cell patch-clamp analysis showed that coculture with LM-MP decreases cell excitability and reduces voltage-gated Na(+) currents but significantly enhances A-current and late afterhyperpolarization (AHP) and increases the expression of the four AHP-generating Ca(2+)-dependent K(+) channel genes (KCNN), compared with control cells. In a separate experiment, differentiation of LM-MP cocultured CNS-NSC produced a significant increase in the numbers of cells that were immune reactive against the neurotransmitters nNOS, ChAT, and the neuropeptide VIP compared with CNS-NSC differentiated similarly in the presence of neonatal brain tissue. Our results show that the gut microenvironment induces CNS-NSC to produce neurons that share some of the characteristics of classical enteric neurons, further supporting the therapeutic use of these cells for gastrointestinal disorders.

Increased Expression of PcG Protein YY1 Negatively Regulates B Cell Development while Allowing Accumulation of Myeloid Cells and LT-HSC Cells

PubMed Central

Pan, Xuan; Jones, Morgan; Jiang, Jie; Zaprazna, Kristina; Yu, Duonan; Pear, Warren; Maillard, Ivan; Atchison, Michael L.

2012-01-01

Ying Yang 1 (YY1) is a multifunctional Polycomb Group (PcG) transcription factor that binds to multiple enhancer binding sites in the immunoglobulin (Ig) loci and plays vital roles in early B cell development. PcG proteins have important functions in hematopoietic stem cell renewal and YY1 is the only mammalian PcG protein with DNA binding specificity. Conditional knock-out of YY1 in the mouse B cell lineage results in arrest at the pro-B cell stage, and dosage effects have been observed at various YY1 expression levels. To investigate the impact of elevated YY1 expression on hematopoetic development, we utilized a mouse in vivo bone marrow reconstitution system. We found that mouse bone marrow cells expressing elevated levels of YY1 exhibited a selective disadvantage as they progressed from hematopoietic stem/progenitor cells to pro-B, pre-B, immature B and re-circulating B cell stages, but no disadvantage of YY1 over-expression was observed in myeloid lineage cells. Furthermore, mouse bone marrow cells expressing elevated levels of YY1 displayed enrichment for cells with surface markers characteristic of long-term hematopoietic stem cells (HSC). YY1 expression induced apoptosis in mouse B cell lines in vitro, and resulted in down-regulated expression of anti-apoptotic genes Bcl-xl and NFκB2, while no impact was observed in a mouse myeloid line. B cell apoptosis and LT-HSC enrichment induced by YY1 suggest that novel strategies to induce YY1 expression could have beneficial effects in the treatment of B lineage malignancies while preserving normal HSCs. PMID:22292011

Irinotecan metabolite SN38 results in germ cell loss in the testis but not in the ovary of prepubertal mice.

PubMed

Lopes, Federica; Smith, Rowena; Nash, Sophie; Mitchell, Rod T; Spears, Norah

2016-11-01

Does the Irinotecan metabolite 7-ethyl-10-hydroxycamptothecan (SN38) damage the gonads of male and female prepubertal mice? The Irinotecan metabolite SN38 reduces germ cell numbers within the seminiferous tubules of mouse testes at concentrations that are relevant to cancer patients, while in contrast it has little if any effect on the female germ cell population. Little is known about the role of the chemotherapeutic agent Irinotecan on female fertility, with only one article to date reporting menopausal symptoms in perimenopausal women treated with Irinotecan, while no data are available either on adult male fertility or on the impact of Irinotecan on the subsequent fertility of prepubertal cancer patients, female or male. Male and female gonads were obtained from postnatal day 5 C57BL/6 mice and exposed in vitro to a range of concentrations of the Irinotecan metabolite SN38: 0.002, 0.01, 0.05, 0.1 or 1 µg ml -1 for the testis and 0.1, 1, 2.5 or 5 µg ml -1 for the ovary, with treated gonads compared to control gonads not exposed to SN38. SN38 was dissolved in 0.5% dimethyl sulfoxide, with controls exposed to the same concentration of diluent. The number of testis fragments used for each analysis ranged between 3 and 9 per treatment group, while the number of ovaries used for each analysis ranged between 4 and 12 per treatment group. Neonatal mouse gonads were developed in vitro, with tissue analysed at the end of the 4-6 day culture period, following immunofluorescence or hematoxylin and eosin staining. Statistical analyses were performed using one-way ANOVA followed by Bonferroni post-hoc test for normally distributed data and Kruskal-Wallis test followed by Dunns post-test for non-parametric data. Abnormal testis morphology was observed when tissues were exposed to SN38, with a smaller seminiferous tubule diameter at the highest concentration of SN38 (1 µg ml -1 , p < 0.001 versus control) and increased number of Sertoli cell-only tubules at the two highest concentrations of SN38 (0.1 µg ml -1 , p < 0.001; 1 µg ml -1 , p < 0.0001, both versus control). Within seminiferous tubules, a dose response decrease was observed in both germ cell number (mouse vasa homologue (MVH)-positive cells) and in proliferating cell number (bromodeoxyuridine (BrdU)-positive cells), with significance reached at the two highest concentrations of SN38 (0.1 µg ml -1 , p < 0.01 for both; 1 µg ml -1 , p < 0.001-MVH, p < 0.01-BrdU; all versus control). No change was seen in protein expression of the apoptotic marker cleaved caspase 3. Double immunofluorescence showed that occasional proliferating germ cells were present in treated testes, even after exposure to the highest drug concentration. When prepubertal ovaries were treated with SN38, no effect was seen on germ cell number, apoptosis or cell proliferation, even after exposure to the highest drug concentrations. As with any study using in vitro experiments with an experimental animal model, caution is required when extrapolating the present findings to humans. Differences between human and mouse spermatogonial development also need to be considered when assessing the effect of chemotherapeutic exposure. However, the prepubertal testes and ovaries used in the present studies contain germ cell populations that are representative of those found in prepubertal patients, and experimental tissues were exposed to drug concentrations within the range found in patient plasma. Our findings demonstrate that the prepubertal mouse ovary is relatively insensitive to exposure to the Irinotecan metabolite SN38, while it induces a marked dose-dependent sensitivity in the testicular germ cell population. The study identifies the importance of further investigation to identify the risk of infertility in young male cancer patients treated with Irinotecan. None. Work supported by Medical Research Grant (MRC) grant G1002118 and Children with Cancer UK grant 15-198. The authors declare that there is no conflict of interest that could prejudice the impartiality of the present research. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.

Human Stem Cells Can Differentiate in Post-implantation Mouse Embryos.

PubMed

Tam, Patrick P L

2016-01-07

The potency of human pluripotent stem cells (hPSCs) to differentiate into germ layer derivatives is conventionally assessed by teratoma induction and in vitro differentiation. In this issue of Cell Stem Cell, Mascetti and Pedersen (2016) demonstrate that the human-mouse post-implantation chimera offers an efficient avenue to test the germ layer differentiation potential of hPSCs in mouse embryos ex vivo. Copyright © 2016 Elsevier Inc. All rights reserved.

Mouse Cytotoxic T Cell-derived Granzyme B Activates the Mitochondrial Cell Death Pathway in a Bim-dependent Fashion*

PubMed Central

Catalán, Elena; Jaime-Sánchez, Paula; Aguiló, Nacho; Simon, Markus M.; Froelich, Christopher J.; Pardo, Julián

2015-01-01

Cytotoxic T cells (Tc) use perforin and granzyme B (gzmB) to kill virus-infected cells and cancer cells. Recent evidence suggests that human gzmB primarily induces apoptosis via the intrinsic mitochondrial pathway by either cleaving Bid or activating Bim leading to the activation of Bak/Bax and subsequent generation of active caspase-3. In contrast, mouse gzmB is thought to predominantly induce apoptosis by directly processing pro-caspase-3. However, in certain mouse cell types gzmB-mediated apoptosis mainly occurs via the mitochondrial pathway. To investigate whether Bim is involved under the latter conditions, we have now employed ex vivo virus-immune mouse Tc that selectively kill by using perforin and gzmB (gzmB+Tc) as effector cells and wild type as well as Bim- or Bak/Bax-deficient spontaneously (3T9) or virus-(SV40) transformed mouse embryonic fibroblast cells as targets. We show that gzmB+Tc-mediated apoptosis (phosphatidylserine translocation, mitochondrial depolarization, cytochrome c release, and caspase-3 activation) was severely reduced in 3T9 cells lacking either Bim or both Bak and Bax. This outcome was related to the ability of Tc cells to induce the degradation of Mcl-1 and Bcl-XL, the anti-apoptotic counterparts of Bim. In contrast, gzmB+Tc-mediated apoptosis was not affected in SV40-transformed mouse embryonic fibroblast cells lacking Bak/Bax. The data provide evidence that Bim participates in mouse gzmB+Tc-mediated apoptosis of certain targets by activating the mitochondrial pathway and suggest that the mode of cell death depends on the target cell. Our results suggest that the various molecular events leading to transformation and/or immortalization of cells have an impact on their relative resistance to the multiple gzmB+Tc-induced death pathways. PMID:25605735

Graphene oxide promotes the differentiation of mouse embryonic stem cells to dopamine neurons.

PubMed

Yang, Dehua; Li, Ting; Xu, Minghan; Gao, Feng; Yang, Juan; Yang, Zhi; Le, Weidong

2014-11-01

Nanoparticles are easier to pass through cell membranes, and they are considered to be the ideal biocompatible and mechanically stable platforms for supporting stem cell growth and differentiation. The aim of this study is to determine the effects of carbon nanotubes (CNTs), graphene oxide (GO) and graphene (GR) on the dopamine neural differentiation of mouse embryonic stem cells (ESCs). GO was prepared according to a modified Hummers method. GR was synthesized by reduction of GO via L-ascorbic acid as a reductant in an aqueous solution at room temperature. CNTs were fabricated by chemical vapor deposition method. ESCs were differentiated by a stromal cell-derived inducing activity (SDIA) method after 10 days coculture with PA6 cells. The dopamine neural differentiation of the ESCs-GFP was examined by immunocytochemistry and real-time PCR. We found that only GO could effectively promote dopamine neuron differentiation after induction of SDIA and further enhance dopamine neuron-related gene expression compared with cells treated with no nanoparticle control, and the other two nanoparticles (CNTs and GR). These findings suggest that GO is a promising nanomaterial-based technical platform to effectively enhance dopamine neural differentiation of ESCs, which can be potentially applied for cell transplantation therapy.

Inhibition of Excessive Monoamine Oxidase A/B Activity Protects Against Stress-induced Neuronal Death in Huntington Disease.

PubMed

Ooi, Jolene; Hayden, Michael R; Pouladi, Mahmoud A

2015-12-01

Monoamine oxidases (MAO) are important components of the homeostatic machinery that maintains the levels of monoamine neurotransmitters, including dopamine, in balance. Given the imbalance in dopamine levels observed in Huntington disease (HD), the aim of this study was to examine MAO activity in a mouse striatal cell model of HD and in human neural cells differentiated from control and HD patient-derived induced pluripotent stem cell (hiPSC) lines. We show that mouse striatal neural cells expressing mutant huntingtin (HTT) exhibit increased MAO expression and activity. We demonstrate using luciferase promoter assays that the increased MAO expression reflects enhanced epigenetic activation in striatal neural cells expressing mutant HTT. Using cellular stress paradigms, we further demonstrate that the increase in MAO activity in mutant striatal neural cells is accompanied by enhanced susceptibility to oxidative stress and impaired viability. Treatment of mutant striatal neural cells with MAO inhibitors ameliorated oxidative stress and improved cellular viability. Finally, we demonstrate that human HD neural cells exhibit increased MAO-A and MAO-B expression and activity. Altogether, this study demonstrates abnormal MAO expression and activity and suggests a potential use for MAO inhibitors in HD.

Antimetastatic Efficacy of the Combination of Caffeine and Valproic Acid on an Orthotopic Human Osteosarcoma Cell Line Model in Nude Mice.

PubMed

Igarashi, Kentaro; Kawaguchi, Kei; Kiyuna, Tasuku; Murakami, Takashi; Yamamoto, Norio; Hayashi, Katsuhiro; Kimura, Hiroaki; Miwa, Shinji; Tsuchiya, Hiroyuki; Hoffman, Robert M

2017-03-01

We have previously reported that caffeine can enhance chemotherapy efficacy of bone and soft tissue sarcoma via cell-cycle perturbation. Valproic acid has histone deacetylase (HDAC) inhibitory activity. We have also reported the anti-tumor efficacy of combination treatment with caffeine and valproic acid against osteosarcoma primary tumors in a cell-line orthotopic mouse model. In this study, we performed combination treatment of caffeine and valproic acid on osteosarcoma cell lines in vitro and in spontaneous and experimental lung metastasis mouse models of osteosarcoma. Survival of 143B-RFP human osteosarcoma cells after exposure to caffeine and valproic acid for 72 hours was determined using the WST-8 assay. IC 50 values and combination indices were calculated. Mouse models of primary osteosarcoma and spontaneous lung metastasis were obtained by orthotopic intra-tibial injection of 143B-RFP cells. Valproic acid, caffeine, and combination of both drugs were administered from day 7, five times a week, for four weeks. Six weeks after orthotopic injection, lung samples were excised and observed with a fluorescence imaging system. A mouse model of experimental lung metastasis was obtained by tail vein injection of 143B-RFP cells. The mice were treated with these agents from day 0, five times a week for four weeks. Both caffeine and valproic acid caused concentration-dependent cell kill in vitro. Synergistic efficacy of the combination treatment was observed. In the spontaneous lung-metastasis model, the number of lung metastasis was 9.0±2.6 in the untreated group (G1); 10.8±2.9 in the caffeine group (G2); 10.0±3.1 in the valproic-acid group (G3); and 3.0±1.1 in the combination group (G4); (p=6.78E-5 control vs. combination; p=0.006 valproic acid vs. combination; p=0.003 caffeine vs. combination). In the experimental lung-metastasis model, the combination group significantly reduced lung metastases and improved overall survival (p=0.0005). Efficacy of the combination of caffeine and valproic acid was observed in vitro and in spontaneous and experimental lung-metastasis mouse models of osteosarcoma. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Lentivirus-mediated bifunctional cell labeling for in vivo melanoma study

PubMed Central

Day, Chi-Ping; Carter, John; Bonomi, Carrie; Esposito, Dominic; Crise, Bruce; Ortiz-Conde, Betty; Hollingshead, Melinda; Merlino, Glenn

2009-01-01

SUMMARY Lentiviral vectors (LVs) are capable of labeling a broad spectrum of cell types, achieving stable expression of transgenes. However, for in vivo studies, the duration of marker gene expression has been highly variable. We have developed a series of LVs harboring different promoters for expressing reporter gene in mouse cells. Long-term culture and colony formation of several LV-labeled mouse melanoma cells showed that promoters derived from mammalian house-keeping genes, especially those encoding RNA polymerase II (Pol2) and ferritin (FerH), provided the highest consistency for reporter expression. For in vivo studies, primary B16BL6 mouse melanoma were infected with LVs whose luciferase-GFP fusion gene (Luc/GFP) was driven by either Pol2 or FerH promoters. When transplanted into syngeneic C57BL/6 mice, Luc/GFP-labeled B16BL6 mouse melanoma cells can be monitored by bioluminescence imaging in vivo, and GFP-positive cells can be isolated from the tumors by FACS. Pol2-Luc/GFP labeling, while lower in activity, was more sustainable than FerH-Luc/GFP labeling in B16BL6 over consecutive passages into mice. We conclude that Pol-2-Luc/GFP labeling allows long-term in vivo monitoring and tumor cell isolation in immunocompetent mouse melanoma models. SIGNIFICANCE In this study we have developed and identified lentiviral vectors that allow labeled mouse melanoma cells to maintain long-term and consistent expression of a bifunctional luciferase-GFP marker gene, even in syngeneic mice with an intact immune function. This cell-labeling system can be used to build immunocompetent mouse melanoma models that permit both tumor monitoring and FACS-based tumor cell isolation from tissues, greatly facilitating the in vivo study of melanoma. PMID:19175523

A transcription factor collective defines the HSN serotonergic neuron regulatory landscape.

PubMed

Lloret-Fernández, Carla; Maicas, Miren; Mora-Martínez, Carlos; Artacho, Alejandro; Jimeno-Martín, Ángela; Chirivella, Laura; Weinberg, Peter; Flames, Nuria

2018-03-22

Cell differentiation is controlled by individual transcription factors (TFs) that together activate a selection of enhancers in specific cell types. How these combinations of TFs identify and activate their target sequences remains poorly understood. Here, we identify the cis -regulatory transcriptional code that controls the differentiation of serotonergic HSN neurons in Caenorhabditis elegans . Activation of the HSN transcriptome is directly orchestrated by a collective of six TFs. Binding site clusters for this TF collective form a regulatory signature that is sufficient for de novo identification of HSN neuron functional enhancers. Among C. elegans neurons, the HSN transcriptome most closely resembles that of mouse serotonergic neurons. Mouse orthologs of the HSN TF collective also regulate serotonergic differentiation and can functionally substitute for their worm counterparts which suggests deep homology. Our results identify rules governing the regulatory landscape of a critically important neuronal type in two species separated by over 700 million years. © 2018, Lloret-Fernández et al.

4-aminopyridine reverses ataxia and cerebellar firing deficiency in a mouse model of spinocerebellar ataxia type 6

PubMed Central

Jayabal, Sriram; Chang, Hui Ho Vanessa; Cullen, Kathleen E.; Watt, Alanna J.

2016-01-01

Spinocerebellar ataxia type 6 (SCA6) is a devastating midlife-onset autosomal dominant motor control disease with no known treatment. Using a hyper-expanded polyglutamine (84Q) knock-in mouse, we found that cerebellar Purkinje cell firing precision was degraded in heterozygous (SCA684Q/+) mice at 19 months when motor deficits are observed. Similar alterations in firing precision and motor control were observed at disease onset at 7 months in homozygous (SCA684Q/84Q) mice, as well as a reduction in firing rate. We further found that chronic administration of the FDA-approved drug 4-aminopyridine (4-AP), which targets potassium channels, alleviated motor coordination deficits and restored cerebellar Purkinje cell firing precision to wildtype (WT) levels in SCA684Q/84Q mice both in acute slices and in vivo. These results provide a novel therapeutic approach for treating ataxic symptoms associated with SCA6. PMID:27381005

4-aminopyridine reverses ataxia and cerebellar firing deficiency in a mouse model of spinocerebellar ataxia type 6.

PubMed

Jayabal, Sriram; Chang, Hui Ho Vanessa; Cullen, Kathleen E; Watt, Alanna J

2016-07-06

Spinocerebellar ataxia type 6 (SCA6) is a devastating midlife-onset autosomal dominant motor control disease with no known treatment. Using a hyper-expanded polyglutamine (84Q) knock-in mouse, we found that cerebellar Purkinje cell firing precision was degraded in heterozygous (SCA6(84Q/+)) mice at 19 months when motor deficits are observed. Similar alterations in firing precision and motor control were observed at disease onset at 7 months in homozygous (SCA6(84Q/84Q)) mice, as well as a reduction in firing rate. We further found that chronic administration of the FDA-approved drug 4-aminopyridine (4-AP), which targets potassium channels, alleviated motor coordination deficits and restored cerebellar Purkinje cell firing precision to wildtype (WT) levels in SCA6(84Q/84Q) mice both in acute slices and in vivo. These results provide a novel therapeutic approach for treating ataxic symptoms associated with SCA6.

The cell-stretcher: A novel device for the mechanical stimulation of cell populations

NASA Astrophysics Data System (ADS)

Seriani, S.; Del Favero, G.; Mahaffey, J.; Marko, D.; Gallina, P.; Long, C. S.; Mestroni, L.; Sbaizero, O.

2016-08-01

Mechanical stimulation appears to be a critical modulator for many aspects of biology, both of living tissue and cells. The cell-stretcher, a novel device for the mechanical uniaxial stimulation of populations of cells, is described. The system is based on a variable stroke cam-lever-tappet mechanism which allows the delivery of cyclic stimuli with frequencies of up to 10 Hz and deformation between 1% and 20%. The kinematics is presented and a simulation of the dynamics of the system is shown, in order to compute the contact forces in the mechanism. The cells, following cultivation and preparation, are plated on an ad hoc polydimethylsiloxane membrane which is then loaded on the clamps of the cell-stretcher via force-adjustable magnetic couplings. In order to show the viability of the experimentation and biocompatibility of the cell-stretcher, a set of two in vitro tests were performed. Human epithelial carcinoma cell line A431 and Adult Mouse Ventricular Fibroblasts (AMVFs) from a dual reporter mouse were subject to 0.5 Hz, 24 h cyclic stretching at 15% strain, and to 48 h stimulation at 0.5 Hz and 15% strain, respectively. Visual analysis was performed on A431, showing definite morphological changes in the form of cellular extroflections in the direction of stimulation compared to an unstimulated control. A cytometric analysis was performed on the AMVF population. Results show a post-stimulation live-dead ratio deviance of less than 6% compared to control, which proves that the environment created by the cell-stretcher is suitable for in vitro experimentation.

Cloning of ES cells and mice by nuclear transfer.

PubMed

Wakayama, Sayaka; Kishigami, Satoshi; Wakayama, Teruhiko

2009-01-01

We have been able to develop a stable nuclear transfer (NT) method in the mouse, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. Although the piezo unit is a complex tool, once mastered it is of great help not only in NT experiments, but also in almost all other forms of micromanipulation. Using this technique, embryonic stem (ntES) cell lines established from somatic cell nuclei can be generated relatively easily from a variety of mouse genotypes and cell types. Such ntES cells can be used not only for experimental models of human therapeutic cloning but also as a means of preserving mouse genomes instead of preserving germ cells. Here, we describe our most recent protocols for mouse cloning.

Prohibitin 2 Regulates the Proliferation and Lineage-Specific Differentiation of Mouse Embryonic Stem Cells in Mitochondria

PubMed Central

Komazaki, Shinji; Enomoto, Kei; Seki, Yasuhiro; Wang, Ying Ying; Ishigaki, Yohei; Ninomiya, Naoto; Noguchi, Taka-aki K.; Kokubu, Yuko; Ohnishi, Keigoh; Nakajima, Yoshiro; Kato, Kaoru; Intoh, Atsushi; Takada, Hitomi; Yamakawa, Norio; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

2014-01-01

Background The pluripotent state of embryonic stem (ES) cells is controlled by a network of specific transcription factors. Recent studies also suggested the significant contribution of mitochondria on the regulation of pluripotent stem cells. However, the molecules involved in these regulations are still unknown. Methodology/Principal Findings In this study, we found that prohibitin 2 (PHB2), a pleiotrophic factor mainly localized in mitochondria, is a crucial regulatory factor for the homeostasis and differentiation of ES cells. PHB2 was highly expressed in undifferentiated mouse ES cells, and the expression was decreased during the differentiation of ES cells. Knockdown of PHB2 induced significant apoptosis in pluripotent ES cells, whereas enhanced expression of PHB2 contributed to the proliferation of ES cells. However, enhanced expression of PHB2 strongly inhibited ES cell differentiation into neuronal and endodermal cells. Interestingly, only PHB2 with intact mitochondrial targeting signal showed these specific effects on ES cells. Moreover, overexpression of PHB2 enhanced the processing of a dynamin-like GTPase (OPA1) that regulates mitochondrial fusion and cristae remodeling, which could induce partial dysfunction of mitochondria. Conclusions/Significance Our results suggest that PHB2 is a crucial mitochondrial regulator for homeostasis and lineage-specific differentiation of ES cells. PMID:24709813

Dynamics of circulating gamma delta T cell activity in an immunocompetent mouse model of high-grade glioma

USDA-ARS?s Scientific Manuscript database

Human gamma delta T cells are potent effectors against glioma cell lines in vitro and in human/mouse xenograft models of glioblastoma, however, this effect has not been investigated in an immunocompetent mouse model. In this report, we established GL261 intracranial gliomas in syngeneic WT C57BL/6 m...

Bmi1 regulates auditory hair cell survival by maintaining redox balance.

PubMed

Chen, Y; Li, L; Ni, W; Zhang, Y; Sun, S; Miao, D; Chai, R; Li, H

2015-01-22

Reactive oxygen species (ROS) accumulation are involved in noise- and ototoxic drug-induced hair cell loss, which is the major cause of hearing loss. Bmi1 is a member of the Polycomb protein family and has been reported to regulate mitochondrial function and ROS level in thymocytes and neurons. In this study, we reported the expression of Bmi1 in mouse cochlea and investigated the role of Bmi1 in hair cell survival. Bmi1 expressed in hair cells and supporting cells in mouse cochlea. Bmi1(-/-) mice displayed severe hearing loss and patched outer hair cell loss from postnatal day 22. Ototoxic drug-induced hair cells loss dramatically increased in Bmi1(-/-) mice compared with that in wild-type controls both in vivo and in vitro, indicating Bmi1(-/-) hair cells were significantly more sensitive to ototoxic drug-induced damage. Cleaved caspase-3 and TUNEL staining demonstrated that apoptosis was involved in the increased hair cell loss of Bmi1(-/-) mice. Aminophenyl fluorescein and MitoSOX Red staining showed the level of free radicals and mitochondrial ROS increased in Bmi1(-/-) hair cells due to the aggravated disequilibrium of antioxidant-prooxidant balance. Furthermore, the antioxidant N-acetylcysteine rescued Bmi1(-/-) hair cells from neomycin injury both in vitro and in vivo, suggesting that ROS accumulation was mainly responsible for the increased aminoglycosides sensitivity in Bmi1(-/-) hair cells. Our findings demonstrate that Bmi1 has an important role in hair cell survival by controlling redox balance and ROS level, thus suggesting that Bmi1 may work as a new therapeutic target for the prevention of hair cell death.

Protective role of Nrf2 against mechanical-stretch-induced apoptosis in mouse fibroblasts: a potential therapeutic target of mechanical-trauma-induced stress urinary incontinence.

PubMed

Li, Qiannan; Li, Bingshu; Liu, Cheng; Wang, Linlin; Tang, Jianming; Hong, Li

2018-01-10

We investigated the protective effect and underlying molecular mechanism of nuclear factor-E2-related factor 2 (Nrf2) against mechanical-stretch-induced apoptosis in mouse fibroblasts. Normal cells, Nrf2 silencing cells, and Nrf2 overexpressing cells were respectively divided into two groups-nonintervention and cyclic mechanical strain (CMS)-subjected to CMS of 5333 μ (1.0 Hz for 4 h), six groups in total (control, CMS, shNfe212, shNfe212 + CMS, LV-shNfe212, and LV-shNfe212 + CMS). After treatment, cell apoptosis; cell-cycle distribution; expressions of Nrf2, Bax, Bcl-2, Cyt-C, caspase-3, caspase-9, cleaved-caspase-3, and cleaved-caspase-9; mitochondrial membrane potential (ΔΨm); reactive oxygen species (ROS); and malondialdehyde (MDA) levels were measured. Thirty virgin female C57BL/6 mice were divided into two groups: control (without intervention) and vaginal distension (VD) groups, which underwent VD for 1 h with an 8-mm dilator (0.3 ml saline). Leak-point pressure (LPP) was tested on day 7 after VD; Nrf2 expression, apoptosis, and MDA levels were then measured in urethra and anterior vaginal wall. Mechanical stretch decreased Nrf2 messenger RNA (mRNA) and protein expressions. Overexpression of Nrf2 alleviated mechanical-stretch-induced cell apoptosis; S-phase arrest of cell cycle; up-regulation of Bax, cytochrome C (Cyt-C), ROS, MDA, ratio of cleaved-caspase-3/caspase-3 and cleaved-caspase-9/caspase-9; and exacerbated the decrease of Bcl2 and ΔΨm in L929 cells. On the contrary, silencing of Nrf2 showed opposite effects. Besides, VD reduced LPP levels and Nrf2 expression and increased cell apoptosis and MDA generation in the urethra and anterior vaginal wall. Nrf2 exhibits a protective role against mechanical-stretch -induced apoptosis on mouse fibroblasts, which might indicate a potential therapeutic target of mechanical-trauma-induced stress urinary incontinence (SUI).

In vivo visualization and ex vivo quantification of murine breast cancer cells in the mouse brain using MRI cell tracking and electron paramagnetic resonance.

PubMed

Danhier, Pierre; Magat, Julie; Levêque, Philippe; De Preter, Géraldine; Porporato, Paolo E; Bouzin, Caroline; Jordan, Bénédicte F; Demeur, Gladys; Haufroid, Vincent; Feron, Olivier; Sonveaux, Pierre; Gallez, Bernard

2015-03-01

Cell tracking could be useful to elucidate fundamental processes of cancer biology such as metastasis. The aim of this study was to visualize, using MRI, and to quantify, using electron paramagnetic resonance (EPR), the entrapment of murine breast cancer cells labeled with superparamagnetic iron oxide particles (SPIOs) in the mouse brain after intracardiac injection. For this purpose, luciferase-expressing murine 4 T1-luc breast cancer cells were labeled with fluorescent Molday ION Rhodamine B SPIOs. Following intracardiac injection, SPIO-labeled 4 T1-luc cells were imaged using multiple gradient-echo sequences. Ex vivo iron oxide quantification in the mouse brain was performed using EPR (9 GHz). The long-term fate of 4 T1-luc cells after injection was characterized using bioluminescence imaging (BLI), brain MRI and immunofluorescence. We observed hypointense spots due to SPIO-labeled cells in the mouse brain 4 h after injection on T2 *-weighted images. Histology studies showed that SPIO-labeled cancer cells were localized within blood vessels shortly after delivery. Ex vivo quantification of SPIOs showed that less than 1% of the injected cells were taken up by the mouse brain after injection. MRI experiments did not reveal the development of macrometastases in the mouse brain several days after injection, but immunofluorescence studies demonstrated that these cells found in the brain established micrometastases. Concerning the metastatic patterns of 4 T1-luc cells, an EPR biodistribution study demonstrated that SPIO-labeled 4 T1-luc cells were also entrapped in the lungs of mice after intracardiac injection. BLI performed 6 days after injection of 4 T1-luc cells showed that this cell line formed macrometastases in the lungs and in the bones. Conclusively, EPR and MRI were found to be complementary for cell tracking applications. MRI cell tracking at 11.7 T allowed sensitive detection of isolated SPIO-labeled cells in the mouse brain, whereas EPR allowed the assessment of the number of SPIO-labeled cells in organs shortly after injection. Copyright © 2015 John Wiley & Sons, Ltd.

Derivation of novel human ground state naive pluripotent stem cells.

PubMed

Gafni, Ohad; Weinberger, Leehee; Mansour, Abed AlFatah; Manor, Yair S; Chomsky, Elad; Ben-Yosef, Dalit; Kalma, Yael; Viukov, Sergey; Maza, Itay; Zviran, Asaf; Rais, Yoach; Shipony, Zohar; Mukamel, Zohar; Krupalnik, Vladislav; Zerbib, Mirie; Geula, Shay; Caspi, Inbal; Schneir, Dan; Shwartz, Tamar; Gilad, Shlomit; Amann-Zalcenstein, Daniela; Benjamin, Sima; Amit, Ido; Tanay, Amos; Massarwa, Rada; Novershtern, Noa; Hanna, Jacob H

2013-12-12

Mouse embryonic stem (ES) cells are isolated from the inner cell mass of blastocysts, and can be preserved in vitro in a naive inner-cell-mass-like configuration by providing exogenous stimulation with leukaemia inhibitory factor (LIF) and small molecule inhibition of ERK1/ERK2 and GSK3β signalling (termed 2i/LIF conditions). Hallmarks of naive pluripotency include driving Oct4 (also known as Pou5f1) transcription by its distal enhancer, retaining a pre-inactivation X chromosome state, and global reduction in DNA methylation and in H3K27me3 repressive chromatin mark deposition on developmental regulatory gene promoters. Upon withdrawal of 2i/LIF, naive mouse ES cells can drift towards a primed pluripotent state resembling that of the post-implantation epiblast. Although human ES cells share several molecular features with naive mouse ES cells, they also share a variety of epigenetic properties with primed murine epiblast stem cells (EpiSCs). These include predominant use of the proximal enhancer element to maintain OCT4 expression, pronounced tendency for X chromosome inactivation in most female human ES cells, increase in DNA methylation and prominent deposition of H3K27me3 and bivalent domain acquisition on lineage regulatory genes. The feasibility of establishing human ground state naive pluripotency in vitro with equivalent molecular and functional features to those characterized in mouse ES cells remains to be defined. Here we establish defined conditions that facilitate the derivation of genetically unmodified human naive pluripotent stem cells from already established primed human ES cells, from somatic cells through induced pluripotent stem (iPS) cell reprogramming or directly from blastocysts. The novel naive pluripotent cells validated herein retain molecular characteristics and functional properties that are highly similar to mouse naive ES cells, and distinct from conventional primed human pluripotent cells. This includes competence in the generation of cross-species chimaeric mouse embryos that underwent organogenesis following microinjection of human naive iPS cells into mouse morulas. Collectively, our findings establish new avenues for regenerative medicine, patient-specific iPS cell disease modelling and the study of early human development in vitro and in vivo.