Comparison of mHTT Antibodies in Huntington’s Disease Mouse Models Reveal Specific Binding Profiles and Steady-State Ubiquitin Levels with Disease Development

PubMed Central

Bayram-Weston, Zubeyde; Jones, Lesley; Dunnett, Stephen B.; Brooks, Simon P.

2016-01-01

Huntington’s disease (HD) cellular pathology is characterised by the aggregation of mutant huntingtin (mHTT) protein into inclusion bodies. The present paper compared the sensitivity of five widely used mHTT antibodies (S830; MW8; EM48; 1C2; ubiquitin) against mice from five commonly used HD mouse models (R6/1; YAC128; HdhQ92; B6 HdhQ150; B6 x129/Ola HdhQ150) at two ages to determine: the most sensitive antibodies for each model; whether mHTT antibody binding differed depending on aggregation stage (diffuse versus frank inclusion); the role of ubiquitin during aggregation as the ubiquitin proteosome system has been implicated in disease development. The models demonstrated unique profiles of antibody binding even when the models varied only by background strain (HdhQ150). MW8 was highly sensitive for detecting frank inclusions in all lines whereas EM48, ubiquitin and 1C2 demonstrated consistent staining in all models irrespective of age or form of mHTT. MW8 and S830 were the most sensitive antibodies with 1C2 the least. Ubiquitin levels were stable for each model regardless of age. Ubiquitin was particularly sensitive in young YAC128 mice that demonstrate an absence of inclusions until ~12 months of age suggesting high affinity to mHTT in its diffuse form. The data indicate that generalisations across models regarding the quantification of aggregations may not be valid and that mHTT antibody binding is unique to the mouse model and sensitive to changes in inclusion development. PMID:27196694

The embryonic mouse hindbrain as a qualitative and quantitative model for studying the molecular and cellular mechanisms of angiogenesis.

PubMed

Fantin, Alessandro; Vieira, Joaquim M; Plein, Alice; Maden, Charlotte H; Ruhrberg, Christiana

2013-02-01

The mouse embryo hindbrain is a robust and adaptable model for studying sprouting angiogenesis. It permits the spatiotemporal analysis of organ vascularization in normal mice and in mouse strains with genetic mutations that result in late embryonic or perinatal lethality. Unlike postnatal models such as retinal angiogenesis or Matrigel implants, there is no requirement for the breeding of conditional knockout mice. The unique architecture of the hindbrain vasculature allows whole-mount immunolabeling of blood vessels and high-resolution imaging, as well as easy quantification of angiogenic sprouting, network density and vessel caliber. The hindbrain model also permits the visualization of ligand binding to blood vessels in situ and the analysis of blood vessel growth within a natural multicellular microenvironment in which endothelial cells (ECs) interact with non-ECs to refine the 3D organ architecture. The entire procedure, from embryo isolation to imaging and through to results analysis, takes approximately 4 d.

Proteomic interactions in the mouse vitreous-retina complex.

PubMed

Skeie, Jessica M; Mahajan, Vinit B

2013-01-01

Human vitreoretinal diseases are due to presumed abnormal mechanical interactions between the vitreous and retina, and translational models are limited. This study determined whether nonstructural proteins and potential retinal biomarkers were expressed by the normal mouse vitreous and retina. Vitreous and retina samples from mice were collected by evisceration and analyzed by liquid chromatography-tandem mass spectrometry. Identified proteins were further analyzed for differential expression and functional interactions using bioinformatic software. We identified 1,680 unique proteins in the retina and 675 unique proteins in the vitreous. Unbiased clustering identified protein pathways that distinguish retina from vitreous including oxidative phosphorylation and neurofilament cytoskeletal remodeling, whereas the vitreous expressed oxidative stress and innate immunology pathways. Some intracellular protein pathways were found in both retina and vitreous, such as glycolysis and gluconeogenesis and neuronal signaling, suggesting proteins might be shuttled between the retina and vitreous. We also identified human disease biomarkers represented in the mouse vitreous and retina, including carbonic anhydrase-2 and 3, crystallins, macrophage inhibitory factor, glutathione peroxidase, peroxiredoxins, S100 precursors, and von Willebrand factor. Our analysis suggests the vitreous expresses nonstructural proteins that functionally interact with the retina to manage oxidative stress, immune reactions, and intracellular proteins may be exchanged between the retina and vitreous. This novel proteomic dataset can be used for investigating human vitreoretinopathies in mouse models. Validation of vitreoretinal biomarkers for human ocular diseases will provide a critical tool for diagnostics and an avenue for therapeutics.

Trial-unique, delayed nonmatching-to-location (TUNL) touchscreen testing for mice: sensitivity to dorsal hippocampal dysfunction.

PubMed

Kim, Chi Hun; Romberg, Carola; Hvoslef-Eide, Martha; Oomen, Charlotte A; Mar, Adam C; Heath, Christopher J; Berthiaume, Andrée-Anne; Bussey, Timothy J; Saksida, Lisa M

2015-11-01

The hippocampus is implicated in many of the cognitive impairments observed in conditions such as Alzheimer's disease (AD) and schizophrenia (SCZ). Often, mice are the species of choice for models of these diseases and the study of the relationship between brain and behaviour more generally. Thus, automated and efficient hippocampal-sensitive cognitive tests for the mouse are important for developing therapeutic targets for these diseases, and understanding brain-behaviour relationships. One promising option is to adapt the touchscreen-based trial-unique nonmatching-to-location (TUNL) task that has been shown to be sensitive to hippocampal dysfunction in the rat. This study aims to adapt the TUNL task for use in mice and to test for hippocampus-dependency of the task. TUNL training protocols were altered such that C57BL/6 mice were able to acquire the task. Following acquisition, dysfunction of the dorsal hippocampus (dHp) was induced using a fibre-sparing excitotoxin, and the effects of manipulation of several task parameters were examined. Mice could acquire the TUNL task using training optimised for the mouse (experiments 1). TUNL was found to be sensitive to dHp dysfunction in the mouse (experiments 2, 3 and 4). In addition, we observed that performance of dHp dysfunction group was somewhat consistently lower when sample locations were presented in the centre of the screen. This study opens up the possibility of testing both mouse and rat models on this flexible and hippocampus-sensitive touchscreen task.

Histopathology reveals correlative and unique phenotypes in a high-throughput mouse phenotyping screen

PubMed Central

Adissu, Hibret A.; Estabel, Jeanne; Sunter, David; Tuck, Elizabeth; Hooks, Yvette; Carragher, Damian M.; Clarke, Kay; Karp, Natasha A.; Project, Sanger Mouse Genetics; Newbigging, Susan; Jones, Nora; Morikawa, Lily; White, Jacqueline K.; McKerlie, Colin

2014-01-01

The Mouse Genetics Project (MGP) at the Wellcome Trust Sanger Institute aims to generate and phenotype over 800 genetically modified mouse lines over the next 5 years to gain a better understanding of mammalian gene function and provide an invaluable resource to the scientific community for follow-up studies. Phenotyping includes the generation of a standardized biobank of paraffin-embedded tissues for each mouse line, but histopathology is not routinely performed. In collaboration with the Pathology Core of the Centre for Modeling Human Disease (CMHD) we report the utility of histopathology in a high-throughput primary phenotyping screen. Histopathology was assessed in an unbiased selection of 50 mouse lines with (n=30) or without (n=20) clinical phenotypes detected by the standard MGP primary phenotyping screen. Our findings revealed that histopathology added correlating morphological data in 19 of 30 lines (63.3%) in which the primary screen detected a phenotype. In addition, seven of the 50 lines (14%) presented significant histopathology findings that were not associated with or predicted by the standard primary screen. Three of these seven lines had no clinical phenotype detected by the standard primary screen. Incidental and strain-associated background lesions were present in all mutant lines with good concordance to wild-type controls. These findings demonstrate the complementary and unique contribution of histopathology to high-throughput primary phenotyping of mutant mice. PMID:24652767

Cloning and characterization of mouse extracellular-signal-regulated protein kinase 3 as a unique gene product of 100 kDa.

PubMed

Turgeon, B; Saba-El-Leil, M K; Meloche, S

2000-02-15

MAP (mitogen-activated protein) kinases are a family of serine/threonine kinases that have a pivotal role in signal transduction. Here we report the cloning and characterization of a mouse homologue of extracellular-signal-regulated protein kinase (ERK)3. The mouse Erk3 cDNA encodes a predicted protein of 720 residues, which displays 94% identity with human ERK3. Transcription and translation of this cDNA in vitro generates a 100 kDa protein similar to the human gene product ERK3. Immunoblot analysis with an antibody raised against a unique sequence of ERK3 also recognizes a 100 kDa protein in mouse tissues. A single transcript of Erk3 was detected in every adult mouse tissue examined, with the highest expression being found in the brain. Interestingly, expression of Erk3 mRNA is acutely regulated during mouse development, with a peak of expression observed at embryonic day 11. The mouse Erk3 gene was mapped to a single locus on central mouse chromosome 9, adjacent to the dilute mutation locus and in a region syntenic to human chromosome 15q21. Finally, we provide several lines of evidence to support the existence of a unique Erk3 gene product of 100 kDa in mammalian cells.

Generation of an inducible colon-specific Cre enzyme mouse line for colon cancer research.

PubMed

Tetteh, Paul W; Kretzschmar, Kai; Begthel, Harry; van den Born, Maaike; Korving, Jeroen; Morsink, Folkert; Farin, Henner; van Es, Johan H; Offerhaus, G Johan A; Clevers, Hans

2016-10-18

Current mouse models for colorectal cancer often differ significantly from human colon cancer, being largely restricted to the small intestine. Here, we aim to develop a colon-specific inducible mouse model that can faithfully recapitulate human colon cancer initiation and progression. Carbonic anhydrase I (Car1) is a gene expressed uniquely in colonic epithelial cells. We generated a colon-specific inducible Car1 CreER knock-in (KI) mouse with broad Cre activity in epithelial cells of the proximal colon and cecum. Deletion of the tumor suppressor gene Apc using the Car1 CreER KI caused tumor formation in the cecum but did not yield adenomas in the proximal colon. Mutation of both Apc and Kras yielded microadenomas in both the cecum and the proximal colon, which progressed to macroadenomas with significant morbidity. Aggressive carcinomas with some invasion into lymph nodes developed upon combined induction of oncogenic mutations of Apc, Kras, p53, and Smad4 Importantly, no adenomas were observed in the small intestine. Additionally, we observed tumors from differentiated Car1-expressing cells with Apc/Kras mutations, suggesting that a top-down model of intestinal tumorigenesis can occur with multiple mutations. Our results establish the Car1 CreER KI as a valuable mouse model to study colon-specific tumorigenesis and metastasis as well as cancer-cell-of-origin questions.

Human vs. Mouse Eosinophils: “That which we call an eosinophil, by any other name would stain as red”

PubMed Central

Lee, James J.; Jacobsen, Elizabeth A.; Ochkur, Sergei I; McGarry, Michael P.; Condjella, Rachel M.; Doyle, Alfred D.; Luo, Huijun; Zellner, Katie R.; Protheroe, Cheryl A.; Willetts, Lian; LeSuer, William E.; Colbert, Dana C.; Helmers, Richard A.; Lacy, Paige; Moqbel, Redwan; Lee, Nancy A.

2012-01-01

The respective life histories of humans and mice are well defined and describe a unique story of evolutionary conservation extending from sequence identity within the genome to the underpinnings of biochemical, cellular, and physiological pathways. As a consequence, the hematopoietic lineages of both species are invariantly maintained, each with identifiable eosinophils. This canonical presence nonetheless does not preclude disparities between human and mouse eosinophils and/or their effector functions. Indeed, many books and reviews dogmatically highlight differences, providing a rationale to discount the use of mouse models of human eosinophilic diseases. We suggest that this perspective is parochial and ignores the wealth of available studies and the consensus of the literature that overwhelming similarities (and not differences) exist between human and mouse eosinophils. The goal of this review is to summarize this literature and in some cases provide the experimental details, comparing and contrasting eosinophils and eosinophil effector functions in humans vs. mice. In particular, our review will provide a summation and an easy to use reference guide to important studies demonstrating that while differences exist, more often than not their consequences are unknown and do not necessarily reflect inherent disparities in eosinophil function, but instead, species-specific variations. The conclusion from this overview is that despite nominal differences, the vast similarities between human and mouse eosinophils provide important insights as to their roles in health and disease and, in turn, demonstrate the unique utility of mouse-based studies with an expectation of valid extrapolation to the understanding and treatment of patients. PMID:22935586

Mutant mouse models and their contribution to our knowledge of corpus luteum development, function and regression.

PubMed

Henkes, Luiz E; Davis, John S; Rueda, Bo R

2003-11-10

The corpus luteum is a unique organ, which is transitory in nature. The development, maintenance and regression of the corpus luteum are regulated by endocrine, paracrine and autocrine signaling events. Defining the specific mediators of luteal development, maintenance and regression has been difficult and often perplexing due to the complexity that stems from the variety of cell types that make up the luteal tissue. Moreover, some regulators may serve dual functions as a luteotropic and luteolytic agent depending on the temporal and spatial environment in which they are expressed. As a result, some confusion is present in the interpretation of in vitro and in vivo studies. More recently investigators have utilized mutant mouse models to define the functional significance of specific gene products. The goal of this mini-review is to identify and discuss mutant mouse models that have luteal anomalies, which may provide some clues as to the significance of specific regulators of corpus luteum function.

nab-paclitaxel potentiates gemcitabine activity by reducing cytidine deaminase levels in a mouse model of pancreatic cancer

PubMed Central

Cook, Natalie; Bapiro, Tashinga E.; Lolkema, Martijn P.; Jodrell, Duncan I.; Tuveson, David A.

2016-01-01

nab-paclitaxel, an albumin-stabilized paclitaxel formulation, demonstrates clinical activity when administered in combination with gemcitabine in patients with metastatic pancreatic ductal adenocarcinoma (PDA). The limited availability of patient tissue and exquisite sensitivity of xenografts to chemotherapeutics have limited our ability to address the mechanistic basis of this treatment regimen. Here, we used a mouse model of PDA to show that the co-administration of nab-paclitaxel and gemcitabine uniquely demonstrates evidence of tumor regression. Combination treatment increases intratumoral gemcitabine levels due to a marked decrease in the primary gemcitabine metabolizing enzyme, cytidine deaminase (Cda). Correspondingly, paclitaxel reduced Cda protein levels in cultured cells through reactive oxygen species-mediated degradation, resulting in the increased stabilization of gemcitabine. Our findings support the concept that suboptimal intratumoral concentrations of gemcitabine represent a crucial mechanism of therapeutic resistance in PDA and highlight the advantages of genetically engineered mouse models in preclinical therapeutic trials. PMID:22585996

The Response Dynamics of Recognition Memory: Sensitivity and Bias

ERIC Educational Resources Information Center

Koop, Gregory J.; Criss, Amy H.

2016-01-01

Advances in theories of memory are hampered by insufficient metrics for measuring memory. The goal of this paper is to further the development of model-independent, sensitive empirical measures of the recognition decision process. We evaluate whether metrics from continuous mouse tracking, or response dynamics, uniquely identify response bias and…

Human immune system mouse models of Ebola virus infection.

PubMed

Spengler, Jessica R; Prescott, Joseph; Feldmann, Heinz; Spiropoulou, Christina F

2017-08-01

Human immune system (HIS) mice, immunodeficient mice engrafted with human cells (with or without donor-matched tissue), offer a unique opportunity to study pathogens that cause disease predominantly or exclusively in humans. Several HIS mouse models have recently been used to study Ebola virus (EBOV) infection and disease. The results of these studies are encouraging and support further development and use of these models in Ebola research. HIS mice provide a small animal model to study EBOV isolates, investigate early viral interactions with human immune cells, screen vaccines and therapeutics that modulate the immune system, and investigate sequelae in survivors. Here we review existing models, discuss their use in pathogenesis studies and therapeutic screening, and highlight considerations for study design and analysis. Finally, we point out caveats to current models, and recommend future efforts for modeling EBOV infection in HIS mice. Published by Elsevier B.V.

Loss of MeCP2 in the rat models regression, impaired sociability and transcriptional deficits of Rett syndrome

PubMed Central

Veeraragavan, Surabi; Wan, Ying-Wooi; Connolly, Daniel R.; Hamilton, Shannon M.; Ward, Christopher S.; Soriano, Sirena; Pitcher, Meagan R.; McGraw, Christopher M.; Huang, Sharon G.; Green, Jennie R.; Yuva, Lisa A.; Liang, Agnes J.; Neul, Jeffrey L.; Yasui, Dag H.; LaSalle, Janine M.; Liu, Zhandong; Paylor, Richard; Samaco, Rodney C.

2016-01-01

Mouse models of the transcriptional modulator Methyl-CpG-Binding Protein 2 (MeCP2) have advanced our understanding of Rett syndrome (RTT). RTT is a ‘prototypical’ neurodevelopmental disorder with many clinical features overlapping with other intellectual and developmental disabilities (IDD). Therapeutic interventions for RTT may therefore have broader applications. However, the reliance on the laboratory mouse to identify viable therapies for the human condition may present challenges in translating findings from the bench to the clinic. In addition, the need to identify outcome measures in well-chosen animal models is critical for preclinical trials. Here, we report that a novel Mecp2 rat model displays high face validity for modelling psychomotor regression of a learned skill, a deficit that has not been shown in Mecp2 mice. Juvenile play, a behavioural feature that is uniquely present in rats and not mice, is also impaired in female Mecp2 rats. Finally, we demonstrate that evaluating the molecular consequences of the loss of MeCP2 in both mouse and rat may result in higher predictive validity with respect to transcriptional changes in the human RTT brain. These data underscore the similarities and differences caused by the loss of MeCP2 among divergent rodent species which may have important implications for the treatment of individuals with disease-causing MECP2 mutations. Taken together, these findings demonstrate that the Mecp2 rat model is a complementary tool with unique features for the study of RTT and highlight the potential benefit of cross-species analyses in identifying potential disease-relevant preclinical outcome measures. PMID:27365498

Non-invasive measurement of cerebral oxygen metabolism in the mouse brain by ultra-high field 17O MR spectroscopy

PubMed Central

Cui, Weina; Zhu, Xiao-Hong; Vollmers, Manda L; Colonna, Emily T; Adriany, Gregor; Tramm, Brandon; Dubinsky, Janet M; Öz, Gülin

2013-01-01

To assess cerebral energetics in transgenic mouse models of neurologic disease, a robust, efficient, and practical method for quantification of cerebral oxygen consumption is needed. 17O magnetic resonance spectroscopy (MRS) has been validated to measure cerebral metabolic rate of oxygen (CMRO2) in the rat brain; however, mice present unique challenges because of their small size. We show that CMRO2 measurements with 17O MRS in the mouse brain are highly reproducible using 16.4 Tesla and a newly designed oxygen delivery system. The method can be utilized to measure mitochondrial function in mice quickly and repeatedly, without oral intubation, and has numerous potential applications to study cerebral energetics. PMID:24064490

Characterization of the Mouse Pancreatic Islet Proteome and Comparative Analysis with Other Mouse Tissues

PubMed Central

Petyuk, Vladislav A.; Qian, Wei-Jun; Hinault, Charlotte; Gritsenko, Marina A.; Singhal, Mudita; Monroe, Matthew E.; Camp, David G.; Kulkarni, Rohit N.; Smith, Richard D.

2009-01-01

The pancreatic islets of Langerhans, and especially the insulin-producing beta cells, play a central role in the maintenance of glucose homeostasis. Alterations in the expression of multiple proteins in the islets that contribute to the maintenance of islet function are likely to underlie the pathogenesis of type 2 diabetes. To identify proteins that constitute the islet proteome, we provide the first comprehensive proteomic characterization of pancreatic islets for mouse, the most commonly used animal model in diabetes research. Using strong cation exchange fractionation coupled with reversed phase LC-MS/MS we report the confident identification of 17,350 different tryptic peptides covering 2,612 proteins having at least two unique peptides per protein. The dataset also identified ~60 post-translationally modified peptides including oxidative modifications and phosphorylation. While many of the identified phosphorylation sites corroborate those previously known, the oxidative modifications observed on cysteinyl residues reveal potentially novel information suggesting a role for oxidative stress in islet function. Comparative analysis with 15 available proteomic datasets from other mouse tissues and cells revealed a set of 133 proteins predominantly expressed in pancreatic islets. This unique set of proteins, in addition to those with known functions such as peptide hormones secreted from the islets, contains several proteins with as yet unknown functions. The mouse islet protein and peptide database accessible at http://ncrr.pnl.gov, provides an important reference resource for the research community to facilitate research in the diabetes and metabolism fields. PMID:18570455

Identification and characterization of poorly differentiated invasive carcinomas in a mouse model of pancreatic neuroendocrine tumorigenesis.

PubMed

Hunter, Karen E; Quick, Marsha L; Sadanandam, Anguraj; Hanahan, Douglas; Joyce, Johanna A

2013-01-01

Pancreatic neuroendocrine tumors (PanNETs) are a relatively rare but clinically challenging tumor type. In particular, high grade, poorly-differentiated PanNETs have the worst patient prognosis, and the underlying mechanisms of disease are poorly understood. In this study we have identified and characterized a previously undescribed class of poorly differentiated PanNETs in the RIP1-Tag2 mouse model. We found that while the majority of tumors in the RIP1-Tag2 model are well-differentiated insulinomas, a subset of tumors had lost multiple markers of beta-cell differentiation and were highly invasive, leading us to term them poorly differentiated invasive carcinomas (PDICs). In addition, we found that these tumors exhibited a high mitotic index, resembling poorly differentiated (PD)-PanNETs in human patients. Interestingly, we identified expression of Id1, an inhibitor of DNA binding gene, and a regulator of differentiation, specifically in PDIC tumor cells by histological analysis. The identification of PDICs in this mouse model provides a unique opportunity to study the pathology and molecular characteristics of PD-PanNETs.

In vitro developmental model of the gastrointestinal tract from mouse embryonic stem cells.

PubMed

Torihashi, Shigeko; Kuwahara, Masaki; Kurahashi, Masaaki

2007-10-01

Mouse embryonic stem (ES) cells are pluripotent and retain their potential to form cells, tissues and organs originated from three embryonic germ layers. Recently, we developed in vitro organ--gut-like structures--from mouse ES cells. They had basically similar morphological features to a mouse gastrointestinal tract in vivo composed of three distinct layers (i.e., epithelium, connective tissue and musculature). Gut-like structures showed spontaneous contractions derived from pacemaker cells (interstitial cells of Cajal) in the musculature. We also examined their formation process and expression pattern of transcription factors crucial for gut organogenesis such as Id2, Sox17, HNF3beta/Foxa2 and GATA4. We found that they mimic the development of embryonic gut in vivo and showed a similar expression pattern of common transcription factors. They also maintain their developmental potential after transplantation to a renal capsule. Therefore, gut-like structures are suitable for in vitro models of gastrointestinal tracts and their development. In addition, we pointed out several unique features different from gut in vivo that provide useful and advantageous tools to investigate the developmental mechanism of the gastrointestinal tract.

Characterization of individual mouse cerebrospinal fluid proteomes

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

Smith, Jeffrey S.; Angel, Thomas E.; Chavkin, Charles

2014-03-20

Analysis of cerebrospinal fluid (CSF) offers key insight into the status of the central nervous system. Characterization of murine CSF proteomes can provide a valuable resource for studying central nervous system injury and disease in animal models. However, the small volume of CSF in mice has thus far limited individual mouse proteome characterization. Through non-terminal CSF extractions in C57Bl/6 mice and high-resolution liquid chromatography-mass spectrometry analysis of individual murine samples, we report the most comprehensive proteome characterization of individual murine CSF to date. Utilizing stringent protein inclusion criteria that required the identification of at least two unique peptides (1% falsemore » discovery rate at the peptide level) we identified a total of 566 unique proteins, including 128 proteins from three individual CSF samples that have been previously identified in brain tissue. Our methods and analysis provide a mechanism for individual murine CSF proteome analysis.« less

Mouse forward genetics in the study of the peripheral nervous system and human peripheral neuropathy

PubMed Central

Douglas, Darlene S.; Popko, Brian

2009-01-01

Forward genetics, the phenotype-driven approach to investigating gene identity and function, has a long history in mouse genetics. Random mutations in the mouse transcend bias about gene function and provide avenues towards unique discoveries. The study of the peripheral nervous system is no exception; from historical strains such as the trembler mouse, which led to the identification of PMP22 as a human disease gene causing multiple forms of peripheral neuropathy, to the more recent identification of the claw paw and sprawling mutations, forward genetics has long been a tool for probing the physiology, pathogenesis, and genetics of the PNS. Even as spontaneous and mutagenized mice continue to enable the identification of novel genes, provide allelic series for detailed functional studies, and generate models useful for clinical research, new methods, such as the piggyBac transposon, are being developed to further harness the power of forward genetics. PMID:18481175

A DNA Vaccine for Crimean Congo Hemorrhagic Fever Protects Against Disease and Death in Two Lethal Mouse Models

DTIC Science & Technology

2017-09-18

hemorrhage. 74 Humans appear to be uniquely affected by CCHFV as infection in other animals, including 75 agricultural animals, does not cause...infected 77 ticks, as well as from exposure to infected agricultural animals during butchering (5). 78 TR-17-120 Distribution Statement A: Approved

Nontransformed, GM-CSF-dependent macrophage lines are a unique model to study tissue macrophage functions.

PubMed

Fejer, György; Wegner, Mareike Dorothee; Györy, Ildiko; Cohen, Idan; Engelhard, Peggy; Voronov, Elena; Manke, Thomas; Ruzsics, Zsolt; Dölken, Lars; Prazeres da Costa, Olivia; Branzk, Nora; Huber, Michael; Prasse, Antje; Schneider, Robert; Apte, Ron N; Galanos, Chris; Freudenberg, Marina A

2013-06-11

Macrophages are diverse cell types in the first line of antimicrobial defense. Only a limited number of primary mouse models exist to study their function. Bone marrow-derived, macrophage-CSF-induced cells with a limited life span are the most common source. We report here a simple method yielding self-renewing, nontransformed, GM-CSF/signal transducer and activator of transcription 5-dependent macrophages (Max Planck Institute cells) from mouse fetal liver, which reflect the innate immune characteristics of alveolar macrophages. Max Planck Institute cells are exquisitely sensitive to selected microbial agents, including bacterial LPS, lipopeptide, Mycobacterium tuberculosis, cord factor, and adenovirus and mount highly proinflammatory but no anti-inflammatory IL-10 responses. They show a unique pattern of innate responses not yet observed in other mononuclear phagocytes. This includes differential LPS sensing and an unprecedented regulation of IL-1α production upon LPS exposure, which likely plays a key role in lung inflammation in vivo. In conclusion, Max Planck Institute cells offer an useful tool to study macrophage biology and for biomedical science.

Molecular and cellular events during blastocyst implantation in the receptive uterus: clues from mouse models

PubMed Central

MATSUMOTO, Hiromichi

2017-01-01

The success of implantation is an interactive process between the blastocyst and the uterus. Synchronized development of embryos with uterine differentiation to a receptive state is necessary to complete pregnancy. The period of uterine receptivity for implantation is limited and referred to as the “implantation window”, which is regulated by ovarian steroid hormones. Implantation process is complicated due to the many signaling molecules in the hierarchical mechanisms with the embryo-uterine dialogue. The mouse is widely used in animal research, and is uniquely suited for reproductive studies, i.e., having a large litter size and brief estrous cycles. This review first describes why the mouse is the preferred model for implantation studies, focusing on uterine morphology and physiological traits, and then highlights the knowledge on uterine receptivity and the hormonal regulation of blastocyst implantation in mice. Our recent study revealed that selective proteolysis in the activated blastocyst is associated with the completion of blastocyst implantation after embryo transfer. Furthermore, in the context of blastocyst implantation in the mouse, this review discusses the window of uterine receptivity, hormonal regulation, uterine vascular permeability and angiogenesis, the delayed-implantation mouse model, morphogens, adhesion molecules, crosslinker proteins, extracellular matrix, and matricellular proteins. A better understanding of uterine and blastocyst biology during the peri-implantation period should facilitate further development of reproductive technology. PMID:28638003

Human versus mouse eosinophils: "that which we call an eosinophil, by any other name would stain as red".

PubMed

Lee, James J; Jacobsen, Elizabeth A; Ochkur, Sergei I; McGarry, Michael P; Condjella, Rachel M; Doyle, Alfred D; Luo, Huijun; Zellner, Katie R; Protheroe, Cheryl A; Willetts, Lian; Lesuer, William E; Colbert, Dana C; Helmers, Richard A; Lacy, Paige; Moqbel, Redwan; Lee, Nancy A

2012-09-01

The respective life histories of human subjects and mice are well defined and describe a unique story of evolutionary conservation extending from sequence identity within the genome to the underpinnings of biochemical, cellular, and physiologic pathways. As a consequence, the hematopoietic lineages of both species are invariantly maintained, each with identifiable eosinophils. This canonical presence nonetheless does not preclude disparities between human and mouse eosinophils, their effector functions, or both. Indeed, many books and reviews dogmatically highlight differences, providing a rationale to discount the use of mouse models of human eosinophilic diseases. We suggest that this perspective is parochial and ignores the wealth of available studies and the consensus of the literature that overwhelming similarities (and not differences) exist between human and mouse eosinophils. The goal of this review is to summarize this literature and in some cases provide experimental details comparing and contrasting eosinophils and eosinophil effector functions in human subjects versus mice. In particular, our review will provide a summation and an easy-to-use reference guide to important studies demonstrating that although differences exist, more often than not, their consequences are unknown and do not necessarily reflect inherent disparities in eosinophil function but instead species-specific variations. The conclusion from this overview is that despite nominal differences, the vast similarities between human and mouse eosinophils provide important insights as to their roles in health and disease and, in turn, demonstrate the unique utility of mouse-based studies with an expectation of valid extrapolation to the understanding and treatment of patients. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Megabladder mouse model of congenital obstructive nephropathy: genetic etiology and renal adaptation.

PubMed

McHugh, Kirk M

2014-04-01

Congenital obstructive nephropathy remains one of the leading causes of chronic renal failure in children. The direct link between obstructed urine flow and abnormal renal development and subsequent dysfunction represents a central paradigm of urogenital pathogenesis that has far-reaching clinical implications. Even so, a number of diagnostic, prognostic, and therapeutic quandaries still exist in the management of congenital obstructive nephropathy. Studies in our laboratory have characterized a unique mutant mouse line that develops in utero megabladder, variable hydronephrosis, and progressive renal failure. Megabladder mice represent a valuable functional model for the study of congenital obstructive nephropathy. Recent studies have begun to shed light on the genetic etiology of mgb (-/-) mice as well as the molecular pathways controlling disease progression in these animals.

A novel phantom model for mouse tumor dose assessment under MV beams

PubMed Central

Gossman, Michael S.; Das, Indra J.; Sharma, Subhash C.; Lopez, Jeffrey P.; Howard, Candace M.; Claudio, Pier P.

2011-01-01

Purpose In order to determine a mouse’s dose accurately and prior to engaging in live mouse radiobiological research, a tissue-equivalent tumor-bearing phantom mouse was constructed and bored to accommodate detectors. Methods and Materials Comparisons were made between four different types of radiation detectors, each inserted into the phantom mouse for radiation measurement under a 6 MV linear accelerator beam. Dose detection response from a diode, thermoluminescent dosimeters, metal-oxide semiconductor field-effect transistors were used and compared to that of a reference pin-point ionization chamber. Likewise, a computerized treatment planning system was also directly compared. Results Each detector system demonstrated results similar to the dose computed by the therapeutic treatment planning system, although some differences were noted. The average disagreement from a accelerator calibrated output dose prescription in the range of 200–400 cGy were −0.4% ± 0.5σ for the diode, −2.4% ± 2.6σ for the TLD, −2.9% ± 5.0σ for the MOSFET and +1.3% ± 1.4σ for the treatment planning system. Conclusions This phantom mouse design is unique, simple, reproducible and therefore recommended as a standard approach to dosimetry for radiobiological mouse studies by means of any of the detectors used in this study. We fully advocate for treatment planning modeling when possible prior to linac-based dose delivery. PMID:22048493

Beyond 'knock-out' mice: new perspectives for the programmed modification of the mammalian genome.

PubMed

Cohen-Tannoudji, M; Babinet, C

1998-10-01

The emergence of gene inactivation by homologous recombination methodology in embryonic stem cells has revolutionized the field of mouse genetics. Indeed, the availability of a rapidly growing number of mouse null mutants has represented an invaluable source of knowledge on mammalian development, cellular biology and physiology and has provided many models for human inherited diseases. In recent years, improvements of the original 'knock-out' strategy, as well as the exploitation of exogenous enzymatic systems that are active in the recombination process, have considerably extended the range of genetic manipulations that can be produced. For example, it is now possible to create a mouse bearing a targeted point mutation as the unique change in its entire genome therefore allowing very fine dissection of gene function in vivo. Chromosome alterations such as large deletions, inversions or translocations can also be designed and will facilitate the global functional analysis of the mouse genome. This will extend the possibilities of creating models of human pathologies that frequently originate from various chromosomal disorders. Finally, the advent of methods allowing conditional gene targeting will open the way for the analysis of the consequence of a particular mutation in a defined organ and at a specific time during the life of a mouse.

NF-κB gene signature predicts prostate cancer progression

PubMed Central

Jin, Renjie; Yi, Yajun; Yull, Fiona E.; Blackwell, Timothy S.; Clark, Peter E.; Koyama, Tatsuki; Smith, Joseph A.; Matusik, Robert J.

2014-01-01

In many prostate cancer (PCa) patients, the cancer will be recurrent and eventually progress to lethal metastatic disease after primary treatment, such as surgery or radiation therapy. Therefore, it would be beneficial to better predict which patients with early-stage PCa would progress or recur after primary definitive treatment. In addition, many studies indicate that activation of NF-κB signaling correlates with PCa progression; however, the precise underlying mechanism is not fully understood. Our studies show that activation of NF-κB signaling via deletion of one allele of its inhibitor, IκBα, did not induce prostatic tumorigenesis in our mouse model. However, activation of NF-κB signaling did increase the rate of tumor progression in the Hi-Myc mouse PCa model when compared to Hi-Myc alone. Using the non-malignant NF-κB activated androgen depleted mouse prostate, a NF-κB Activated Recurrence Predictor 21 (NARP21) gene signature was generated. The NARP21 signature successfully predicted disease-specific survival and distant metastases-free survival in patients with PCa. This transgenic mouse model derived gene signature provides a useful and unique molecular profile for human PCa prognosis, which could be used on a prostatic biopsy to predict indolent versus aggressive behavior of the cancer after surgery. PMID:24686169

Preclinical mouse model to monitor live Muc5b-producing conjunctival goblet cell density under pharmacological treatments.

PubMed

Portal, Céline; Gouyer, Valérie; Gottrand, Frédéric; Desseyn, Jean-Luc

2017-01-01

Modification of mucous cell density and gel-forming mucin production are established hallmarks of mucosal diseases. Our aim was to develop and validate a mouse model to study live goblet cell density in pathological situations and under pharmacological treatments. We created a reporter mouse for the gel-forming mucin gene Muc5b. Muc5b-positive goblet cells were studied in the eye conjunctiva by immunohistochemistry and probe-based confocal laser endomicroscopy (pCLE) in living mice. Dry eye syndrome (DES) model was induced by topical application of benzalkonium chloride (BAK) and recombinant interleukine (rIL) 13 was administered to reverse the goblet cell loss in the DES model. Almost 50% of the total of conjunctival goblet cells are Muc5b+ in unchallenged mice. The decrease density of Muc5b+ conjunctival goblet cell population in the DES model reflects the whole conjunctival goblet cell loss. Ten days of BAK in one eye followed by 4 days without any treatment induced a -18.3% decrease in conjunctival goblet cell density. A four days of rIL13 application in the DES model restored the normal goblet cell density. Muc5b is a biological marker of DES mouse models. We bring the proof of concept that our model is unique and allows a better understanding of the mechanisms that regulate gel-forming mucin production/secretion and mucous cell differentiation in the conjunctiva of living mice and can be used to test treatment compounds in mucosal disease models.

MOUSE LIVER TUMOR DATA: ASSESSMENT OF CARCINOGENIC ACTIVITY

EPA Science Inventory

A significant number of chemicals have been shown to be carcinogenic in mouse liver while lacking carcinogenic activity in other organs or tissues of mice or rats. The review focus on the reasons for the unique susceptibility of the mouse liver to these carcinogens, and the exten...

Somatic Cell Nuclear Transfer in the Mouse

NASA Astrophysics Data System (ADS)

Kishigami, Satoshi; Wakayama, Teruhiko

Somatic cell nuclear transfer (SCNT) has become a unique and powerful tool for epigenetic reprogramming research and gene manipulation in animals since “Dolly,” the first animal cloned from an adult cell was reported in 1997. Although the success rates of somatic cloning have been inefficient and the mechanism of reprogramming is still largely unknown, this technique has been proven to work in more than 10 mammalian species. Among them, the mouse provides the best model for both basic and applied research of somatic cloning because of its abounding genetic resources, rapid sexual maturity and propagation, minimal requirements for housing, etc. This chapter describes a basic protocol for mouse cloning using cumulus cells, the most popular cell type for NT, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. In particular, we focus on a new, more efficient mouse cloning protocol using trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which increases both in vitro and in vivo developmental rates from twofold to fivefold. This new method including TSA will be helpful to establish mouse cloning in many laboratories.

Liver Transplantation in the Mouse: Insights Into Liver Immunobiology, Tissue Injury and Allograft Tolerance

PubMed Central

Yokota, Shinichiro; Yoshida, Osamu; Ono, Yoshihiro; Geller, David A.; Thomson, Angus W.

2016-01-01

The surgically-demanding mouse orthotopic liver transplant model was first described in 1991. It has proved a powerful research tool for investigation of liver biology, tissue injury, the regulation of alloimmunity and tolerance induction and the pathogenesis of specific liver diseases. Liver transplantation in mice has unique advantages over transplantation of the liver in larger species, such as the rat or pig, since the mouse genome is well-characterized and there is much greater availability of both genetically-modified animals and research reagents. Liver transplant experiments using various transgenic or gene knockout mice has provided valuable mechanistic insights into the immuno- and pathobiology of the liver and the regulation of graft rejection and tolerance over the past 25 years. The molecular pathways identified in regulation of tissue injury and promotion of liver transplant tolerance provide new potential targets for therapeutic intervention to control adverse inflammatory responses/ immune-mediated events in the hepatic environment and systemically. Conclusion: Orthotopic liver transplantation in the mouse is a valuable model for gaining improved insights into liver biology, immunopathology and allograft tolerance that may result in therapeutic innovation in liver and other diseases. PMID:26709949

A Deformable Atlas of the Laboratory Mouse

PubMed Central

Wang, Hongkai; Stout, David B.; Chatziioannou, Arion F.

2015-01-01

Purpose This paper presents a deformable mouse atlas of the laboratory mouse anatomy. This atlas is fully articulated and can be positioned into arbitrary body poses. The atlas can also adapt body weight by changing body length and fat amount. Procedures A training set of 103 micro-CT images was used to construct the atlas. A cage-based deformation method was applied to realize the articulated pose change. The weight-related body deformation was learned from the training set using a linear regression method. A conditional Gaussian model and thin-plate spline mapping were used to deform the internal organs following the changes of pose and weight. Results The atlas was deformed into different body poses and weights, and the deformation results were more realistic compared to the results achieved with other mouse atlases. The organ weights of this atlas matched well with the measurements of real mouse organ weights. This atlas can also be converted into voxelized images with labeled organs, pseudo CT images and tetrahedral mesh for phantom studies. Conclusions With the unique ability of articulated pose and weight changes, the deformable laboratory mouse atlas can become a valuable tool for preclinical image analysis. PMID:25049072

A unique mouse strain that develops spontaneous, iodine-accelerated, pathogenic antibodies to the human thyrotrophin receptor 1

PubMed Central

Rapoport, Basil; Aliesky, Holly A.; Banuelos, Bianca; Chen, Chun-Rong; McLachlan, Sandra M.

2015-01-01

Antibodies that stimulate the thyrotropin receptor (TSHR), the cause of Graves’ hyperthyroidism, only develop in humans. TSHR antibodies can be induced in mice by immunization but studying pathogenesis and therapeutic intervention requires a model without immunization. Spontaneous, iodine-accelerated, thyroid autoimmunity develops in NOD.H2h4 mice associated with thyroglobulin and thyroid-peroxidase, but not TSHR, antibodies. We hypothesized that transferring the human (h)TSHR A-subunit to NOD.H2h4 mice would result in loss of tolerance to this protein. BALB/c hTSHR A-subunit mice were bred to NOD.H2h4 mice and transgenic offspring were repeatedly backcrossed to NOD.H2h4 mice. All offspring developed antibodies to thyroglobulin and thyroid-peroxidase. However, only TSHR-transgenic NOD.H2h4 mice (TSHR/NOD.H2h4) developed pathogenic TSHR antibodies as detected using clinical Graves’ disease assays. As in humans, TSHR/NOD.H2h4 females were more prone than males to developing pathogenic TSHR antibodies. Fortunately, in view of the confounding effect of excess thyroid hormone on immune responses, spontaneously arising pathogenic (h)TSHR antibodies cross-react poorly with the mouse TSHR and do not cause thyrotoxicosis. In summary, the TSHR/NOD.H2h4 mouse strain develops spontaneous, iodine-accelerated, pathogenic TSHR antibodies in females, providing a unique model to investigate disease pathogenesis and test novel TSHR-antigen specific immunotherapies aimed at curing Graves’ disease in humans. PMID:25825442

Excessive nest building is a unique behavioural phenotype in the deer mouse model of obsessive-compulsive disorder.

PubMed

Wolmarans, De Wet; Stein, Dan J; Harvey, Brian H

2016-09-01

Obsessive-compulsive disorder (OCD) is a phenotypically heterogeneous condition characterised by time-consuming intrusive thoughts and/or compulsions. Irrespective of the symptom type diagnosed, the severity of OCD is characterised by heterogeneity in symptom presentation that complicates diagnosis and treatment. Heterogeneity of symptoms would be invaluable in an animal model. Nest building behaviour forms part of the normal behavioural repertoire of rodents and demonstrates profound between-species differences. However, it has been proposed that within-species differences in nest building behaviour (i.e. aberrant vs. normal nest building) may resemble obsessive-compulsive-like symptoms. In an attempt to investigate whether other obsessive-compulsive-like behaviours are present in an animal model of OCD, or if aberrant nest building behaviour may represent a unique obsessive-compulsive phenotype in such a model, the current study assessed nest building behaviour in high (H, viz obsessive-compulsive) and non (N, viz normal) stereotypical deer mice. Subsequently, 12 N and H animals, respectively, were provided with an excess of cotton wool daily for one week prior to and following four weeks of high-dose oral escitalopram treatment (50 mg/kg/day). Data from the current investigation demonstrate daily nesting activity to be highly variable in deer mice, with stereotypy and nest building being independent behaviours. However, we identified unique aberrant large nest building behaviour in 30% of animals from both cohorts that was attenuated by escitalopram to pre-treatment nesting scores of the larger group. In summary, behavioural and drug-treatment evidence confirms that deer mouse behaviour does indeed resemble symptom heterogeneity related to OCD, and as such expands its face and predictive validity for the disorder. © The Author(s) 2016.

RNA-seq based transcriptomic map reveals new insights into mouse salivary gland development and maturation.

PubMed

Gluck, Christian; Min, Sangwon; Oyelakin, Akinsola; Smalley, Kirsten; Sinha, Satrajit; Romano, Rose-Anne

2016-11-16

Mouse models have served a valuable role in deciphering various facets of Salivary Gland (SG) biology, from normal developmental programs to diseased states. To facilitate such studies, gene expression profiling maps have been generated for various stages of SG organogenesis. However these prior studies fall short of capturing the transcriptional complexity due to the limited scope of gene-centric microarray-based technology. Compared to microarray, RNA-sequencing (RNA-seq) offers unbiased detection of novel transcripts, broader dynamic range and high specificity and sensitivity for detection of genes, transcripts, and differential gene expression. Although RNA-seq data, particularly under the auspices of the ENCODE project, have covered a large number of biological specimens, studies on the SG have been lacking. To better appreciate the wide spectrum of gene expression profiles, we isolated RNA from mouse submandibular salivary glands at different embryonic and adult stages. In parallel, we processed RNA-seq data for 24 organs and tissues obtained from the mouse ENCODE consortium and calculated the average gene expression values. To identify molecular players and pathways likely to be relevant for SG biology, we performed functional gene enrichment analysis, network construction and hierarchal clustering of the RNA-seq datasets obtained from different stages of SG development and maturation, and other mouse organs and tissues. Our bioinformatics-based data analysis not only reaffirmed known modulators of SG morphogenesis but revealed novel transcription factors and signaling pathways unique to mouse SG biology and function. Finally we demonstrated that the unique SG gene signature obtained from our mouse studies is also well conserved and can demarcate features of the human SG transcriptome that is different from other tissues. Our RNA-seq based Atlas has revealed a high-resolution cartographic view of the dynamic transcriptomic landscape of the mouse SG at various stages. These RNA-seq datasets will complement pre-existing microarray based datasets, including the Salivary Gland Molecular Anatomy Project by offering a broader systems-biology based perspective rather than the classical gene-centric view. Ultimately such resources will be valuable in providing a useful toolkit to better understand how the diverse cell population of the SG are organized and controlled during development and differentiation.

Animal models for HIV/AIDS research

PubMed Central

Hatziioannou, Theodora; Evans, David T.

2015-01-01

The AIDS pandemic continues to present us with unique scientific and public health challenges. Although the development of effective antiretroviral therapy has been a major triumph, the emergence of drug resistance requires active management of treatment regimens and the continued development of new antiretroviral drugs. Moreover, despite nearly 30 years of intensive investigation, we still lack the basic scientific knowledge necessary to produce a safe and effective vaccine against HIV-1. Animal models offer obvious advantages in the study of HIV/AIDS, allowing for a more invasive investigation of the disease and for preclinical testing of drugs and vaccines. Advances in humanized mouse models, non-human primate immunogenetics and recombinant challenge viruses have greatly increased the number and sophistication of available mouse and simian models. Understanding the advantages and limitations of each of these models is essential for the design of animal studies to guide the development of vaccines and antiretroviral therapies for the prevention and treatment of HIV-1 infection. PMID:23154262

Genome engineering via homologous recombination in mouse embryonic stem (ES) cells: an amazingly versatile tool for the study of mammalian biology.

PubMed

Babinet, C; Cohen-Tannoudji, M

2001-09-01

The ability to introduce genetic modifications in the germ line of complex organisms has been a long-standing goal of those who study developmental biology. In this regard, the mouse, a favorite model for the study of the mammals, is unique: indeed not only is it possible since the late seventies, to add genes to the mouse genome like in several other complex organisms but also to perform gene replacement and modification. This has been made possible via two technological breakthroughs: 1) the isolation and culture of embryonic stem cells (ES), which have the unique ability to colonize all the tissues of an host embryo including its germ line; 2) the development of methods allowing homologous recombination between an incoming DNA and its cognate chromosomal sequence (gene "targeting"). As a result, it has become possible to create mice bearing null mutations in any cloned gene (knock-out mice). Such a possibility has revolutionized the genetic approach of almost all aspects of the biology of the mouse. In recent years, the scope of gene targeting has been widened even more, due to the refinement of the knock-out technology: other types of genetic modifications may now be created, including subtle mutations (point mutations, micro deletions or insertions, etc.) and chromosomal rearrangements such as large deletions, duplications and translocations. Finally, methods have been devised which permit the creation of conditional mutations, allowing the study of gene function throughout the life of an animal, when gene inactivation entails embryonic lethality. In this paper, we present an overview of the methods and scenarios used for the programmed modification of mouse genome, and we underline their enormous interest for the study of mammalian biology.

Characterization, design, and function of the mitochondrial proteome: from organs to organisms.

PubMed

Lotz, Christopher; Lin, Amanda J; Black, Caitlin M; Zhang, Jun; Lau, Edward; Deng, Ning; Wang, Yueju; Zong, Nobel C; Choi, Jeong H; Xu, Tao; Liem, David A; Korge, Paavo; Weiss, James N; Hermjakob, Henning; Yates, John R; Apweiler, Rolf; Ping, Peipei

2014-02-07

Mitochondria are a common energy source for organs and organisms; their diverse functions are specialized according to the unique phenotypes of their hosting environment. Perturbation of mitochondrial homeostasis accompanies significant pathological phenotypes. However, the connections between mitochondrial proteome properties and function remain to be experimentally established on a systematic level. This uncertainty impedes the contextualization and translation of proteomic data to the molecular derivations of mitochondrial diseases. We present a collection of mitochondrial features and functions from four model systems, including two cardiac mitochondrial proteomes from distinct genomes (human and mouse), two unique organ mitochondrial proteomes from identical genetic codons (mouse heart and mouse liver), as well as a relevant metazoan out-group (drosophila). The data, composed of mitochondrial protein abundance and their biochemical activities, capture the core functionalities of these mitochondria. This investigation allowed us to redefine the core mitochondrial proteome from organs and organisms, as well as the relevant contributions from genetic information and hosting milieu. Our study has identified significant enrichment of disease-associated genes and their products. Furthermore, correlational analyses suggest that mitochondrial proteome design is primarily driven by cellular environment. Taken together, these results connect proteome feature with mitochondrial function, providing a prospective resource for mitochondrial pathophysiology and developing novel therapeutic targets in medicine.

A missing piece: the spiny mouse and the puzzle of menstruating species.

PubMed

Bellofiore, Nadia; Cousins, Fiona; Temple-Smith, Peter; Dickinson, Hayley; Evans, Jemma

2018-07-01

We recently discovered the first known menstruating rodent. With the exception of four bats and the elephant shrew, the common spiny mouse ( Acomys cahirinus ) is the only species outside the primate order to exhibit menses. There are few widely accepted theories on why menstruation developed as the preferred reproductive strategy of these select mammals, all of which reference the evolution of spontaneous decidualisation prior to menstrual shedding. Though menstruating species share several reproductive traits, there has been no identifiable feature unique to menstruating species. Such a feature might suggest why spontaneous decidualisation, and thus menstruation, evolved in these species. We propose that a ≥3-fold increase in progesterone during the luteal phase of the reproductive cycle is a unique characteristic linking menstruating species. We discuss spontaneous decidualisation as a consequence of high progesterone, and the potential role of prolactin in screening for defective embryos in these species to aid in minimising implantation of abnormal embryos. We further explore the possible impact of nutrition in selecting species to undergo spontaneous decidualisation and subsequent menstruation. We summarise the current knowledge of menstruation, discuss current pre-clinical models of menstruation and how the spiny mouse may benefit advancing our understanding of this rare biological phenomenon. © 2018 Society for Endocrinology.

Predicting Mouse Liver Microsomal Stability with “Pruned” Machine Learning Models and Public Data

PubMed Central

Perryman, Alexander L.; Stratton, Thomas P.; Ekins, Sean; Freundlich, Joel S.

2015-01-01

Purpose Mouse efficacy studies are a critical hurdle to advance translational research of potential therapeutic compounds for many diseases. Although mouse liver microsomal (MLM) stability studies are not a perfect surrogate for in vivo studies of metabolic clearance, they are the initial model system used to assess metabolic stability. Consequently, we explored the development of machine learning models that can enhance the probability of identifying compounds possessing MLM stability. Methods Published assays on MLM half-life values were identified in PubChem, reformatted, and curated to create a training set with 894 unique small molecules. These data were used to construct machine learning models assessed with internal cross-validation, external tests with a published set of antitubercular compounds, and independent validation with an additional diverse set of 571 compounds (PubChem data on percent metabolism). Results “Pruning” out the moderately unstable/moderately stable compounds from the training set produced models with superior predictive power. Bayesian models displayed the best predictive power for identifying compounds with a half-life ≥1 hour. Conclusions Our results suggest the pruning strategy may be of general benefit to improve test set enrichment and provide machine learning models with enhanced predictive value for the MLM stability of small organic molecules. This study represents the most exhaustive study to date of using machine learning approaches with MLM data from public sources. PMID:26415647

Predicting Mouse Liver Microsomal Stability with "Pruned" Machine Learning Models and Public Data.

PubMed

Perryman, Alexander L; Stratton, Thomas P; Ekins, Sean; Freundlich, Joel S

2016-02-01

Mouse efficacy studies are a critical hurdle to advance translational research of potential therapeutic compounds for many diseases. Although mouse liver microsomal (MLM) stability studies are not a perfect surrogate for in vivo studies of metabolic clearance, they are the initial model system used to assess metabolic stability. Consequently, we explored the development of machine learning models that can enhance the probability of identifying compounds possessing MLM stability. Published assays on MLM half-life values were identified in PubChem, reformatted, and curated to create a training set with 894 unique small molecules. These data were used to construct machine learning models assessed with internal cross-validation, external tests with a published set of antitubercular compounds, and independent validation with an additional diverse set of 571 compounds (PubChem data on percent metabolism). "Pruning" out the moderately unstable / moderately stable compounds from the training set produced models with superior predictive power. Bayesian models displayed the best predictive power for identifying compounds with a half-life ≥1 h. Our results suggest the pruning strategy may be of general benefit to improve test set enrichment and provide machine learning models with enhanced predictive value for the MLM stability of small organic molecules. This study represents the most exhaustive study to date of using machine learning approaches with MLM data from public sources.

Misbehaving macrophages in the pathogenesis of psoriasis.

PubMed

Clark, Rachael A; Kupper, Thomas S

2006-08-01

Psoriasis is a chronic inflammatory skin disease unique to humans. In this issue of the JCI, 2 studies of very different mouse models of psoriasis both report that macrophages play a key role in inducing psoriasis-like skin disease. Psoriasis is clearly a polygenic, inherited disease of uncontrolled cutaneous inflammation. The debate that currently rages in the field is whether psoriasis is a disease of autoreactive T cells or whether it reflects an intrinsic defect within the skin--or both. However, these questions have proven difficult to dissect using molecular genetic tools. In the current studies, the authors have used 2 different animal models to address the role of macrophages in disease pathogenesis: Wang et al. use a mouse model in which inflammation is T cell dependent, whereas the model used by Stratis et al. is T cell independent (see the related articles beginning on pages 2105 and 2094, respectively). Strikingly, both groups report an important contribution by macrophages, implying that macrophages can contribute to both epithelial-based and T cell-mediated pathways of inflammation.

Morphology of the lumbar transversospinal muscles examined in a mouse bearing a muscle fiber-specific nuclear marker.

PubMed

Cornwall, Jon; Deries, Marianne; Duxson, Marilyn

2010-12-01

Although the morphology of human lumbar transversospinal (TSP) muscles has been studied, little is known about the structure of these muscles in the mouse (Mus musculus). Such information is relevant given mice are often used as a "normal" phenotype for studies modeling human development. This study describes the gross morphology, muscle fiber arrangement, and innervation pattern of the mouse lumbar TSP muscles. A unique feature of the study is the use of a transgenic mouse line bearing a muscle-specific nuclear marker that allows clear delineation of muscle fiber and connective tissue boundaries. The lumbar TSP muscles of five mice were examined bilaterally; at each spinal level muscles attached to the caudal edge of the spinous process and passed caudally as a single complex unit. Fibers progressively terminated over the four vertebral segments caudad, with multiple points of muscle fiber attachment on each vertebra. Motor endplates, defined with acetylcholinesterase histochemistry, were consistently located half way along each muscle fiber, regardless of length, with all muscle fibers arranged in-parallel rather than in-series. These results provide information relevant to interpretation of developmental and functional studies involving this muscle group in the mouse and show mouse lumbar TSP muscles are different in form to descriptions of equivalent muscles in humans and horses.

A mouse model for pain and neuroplastic changes associated with pancreatic ductal adenocarcinoma.

PubMed

Selvaraj, Deepitha; Hirth, Michael; Gandla, Jagadeesh; Kuner, Rohini

2017-08-01

Pancreatic ductal adenocarcinoma (PDAC) continues to be one of the deadliest human malignancies and is associated with excruciating pain, which is a serious complication and severely impacts the quality of life in patients. In human patients, poor survival prognosis is linked to remarkable remodeling of intrapancreatic nerves, which, in turn, is correlated to increased pain intensity. Understanding mechanisms underlying pain associated with PDAC has been hampered by the lack of animal models which replicate all germane aspects of the disease and importantly, enable analyses of pain associated with PDAC. In this study, we describe an immunocompetent orthotopic mouse model of PDAC involving intrapancreatic growth of K8484 mouse PDAC cells, which reliably exhibits a large number of key characteristics of human PDAC, including its unique histopathology and neuroplastic changes. We observed that tumor-bearing mice demonstrated significant abdominal mechanical hypersensitivity to von Frey stimuli as well as on-going pain in the conditioned place preference paradigm. Moreover, a myriad of other behavioral tests revealed that indicators of overall well-being were significantly reduced in tumor-bearing mice as compared to sham mice. Morphological and immunohistochemical analyses revealed structural remodeling in several different types of sensory and autonomic nerve fibers. Finally, perineural invasion of tumor cells, a cardinal manifestation in human PDAC, was also observed in our orthotopic mouse model. Thus, we describe a validated tumor model for quantitatively testing hypersensitivity and pain in PDAC, which lays a crucial basis for interrogating tumor-nerve interactions and the molecular and cellular mechanisms underlying pain in PDAC.

Cardiac function and perfusion dynamics measured on a beat-by-beat basis in the live mouse using ultra-fast 4D optoacoustic imaging

NASA Astrophysics Data System (ADS)

Ford, Steven J.; Deán-Ben, Xosé L.; Razansky, Daniel

2015-03-01

The fast heart rate (~7 Hz) of the mouse makes cardiac imaging and functional analysis difficult when studying mouse models of cardiovascular disease, and cannot be done truly in real-time and 3D using established imaging modalities. Optoacoustic imaging, on the other hand, provides ultra-fast imaging at up to 50 volumetric frames per second, allowing for acquisition of several frames per mouse cardiac cycle. In this study, we combined a recently-developed 3D optoacoustic imaging array with novel analytical techniques to assess cardiac function and perfusion dynamics of the mouse heart at high, 4D spatiotemporal resolution. In brief, the heart of an anesthetized mouse was imaged over a series of multiple volumetric frames. In another experiment, an intravenous bolus of indocyanine green (ICG) was injected and its distribution was subsequently imaged in the heart. Unique temporal features of the cardiac cycle and ICG distribution profiles were used to segment the heart from background and to assess cardiac function. The 3D nature of the experimental data allowed for determination of cardiac volumes at ~7-8 frames per mouse cardiac cycle, providing important cardiac function parameters (e.g., stroke volume, ejection fraction) on a beat-by-beat basis, which has been previously unachieved by any other cardiac imaging modality. Furthermore, ICG distribution dynamics allowed for the determination of pulmonary transit time and thus additional quantitative measures of cardiovascular function. This work demonstrates the potential for optoacoustic cardiac imaging and is expected to have a major contribution toward future preclinical studies of animal models of cardiovascular health and disease.

Spallanzani's mouse: a model of restoration and regeneration.

PubMed

Heber-Katz, E; Leferovich, J M; Bedelbaeva, K; Gourevitch, D

2004-01-01

The ability to regenerate is thought to be a lost phenotype in mammals, though there are certainly sporadic examples of mammalian regeneration. Our laboratory has identified a strain of mouse, the MRL mouse, which has a unique capacity to heal complex tissue in an epimorphic fashion, i.e., to restore a damaged limb or organ to its normal structure and function. Initial studies using through-and-through ear punches showed rapid full closure of the ear holes with cartilage growth, new hair follicles, and normal tissue architecture reminiscent of regeneration seen in amphibians as opposed to the scarring usually seen in mammals. Since the ear hole closure phenotype is a quantitative trait, this has been used to show-through extensive breeding and backcrossing--that the trait is heritable. Such analysis reveals that there is a complex genetic basis for this trait with multiple loci. One of the major phenotypes of the MRL mouse is a potent remodeling response with the absence or a reduced level of scarring. MRL healing is associated with the upregulation of the metalloproteinases MMP-2 and MMP-9 and the downregulation of their inhibitors TIMP-2 and TIMP-3, both present in inflammatory cells such as neutrophils and macrophages. This model has more recently been extended to the heart. In this case, a cryoinjury to the right ventricle leads to near complete scarless healing in the MRL mouse whereas scarring is seen in the control mouse. In the MRL heart, bromodeoxyuridine uptake by cardiomyocytes filling the wound site can be seen 60 days after injury. This does not occur in the control mouse. Function in the MRL heart, as measured by echocardiography, returns to normal.

Distinct intestinal adaptation for vitamin B12 and bile acid absorption revealed in a new mouse model of massive ileocecal resection.

PubMed

Matsumoto, Yuka; Mochizuki, Wakana; Akiyama, Shintaro; Matsumoto, Taichi; Nozaki, Kengo; Watanabe, Mamoru; Nakamura, Tetsuya

2017-09-15

Ileocecal resection (ICR), one of several types of intestinal resection that results in short bowel syndrome (SBS), causes severe clinical disease in humans. We here describe a mouse model of massive ICR in which 75% of the distal small intestine is removed. We demonstrate that mice underwent 75% ICR show severe clinical signs and high mortality, which may recapitulate severe forms of human SBS, despite an adaptive response throughout the remnant intestine. By using this model, we also investigated whether the epithelium of the remnant intestine shows enhanced expression of factors involved in region-specific functions of the ileum. Cubn mRNA and its protein product, which play an essential role in vitamin B12 absorption in the ileum, are not compensatory up-regulated in any part of the remnant intestine, demonstrating a clear contrast with post-operative up-regulation of genes involved in bile acid absorption. Our study suggests that functional adaptation by phenotypical changes in the intestinal epithelium is not a general feature for nutrient absorption systems that are confined to the ileum. We also propose that the mouse model developed in this study will become a unique system to facilitate studies on SBS with ICR in humans. © 2017. Published by The Company of Biologists Ltd.

Cyanine 5.5 Conjugated Nanobubbles as a Tumor Selective Contrast Agent for Dual Ultrasound-Fluorescence Imaging in a Mouse Model

PubMed Central

Li, Jing; Wei, Qiong; Yuchi, Ming; He, Xiaoling; Ding, Mingyue; Zhou, Qibing

2013-01-01

Nanobubbles and microbubbles are non-invasive ultrasound imaging contrast agents that may potentially enhance diagnosis of tumors. However, to date, both nanobubbles and microbubbles display poor in vivo tumor-selectivity over non-targeted organs such as liver. We report here cyanine 5.5 conjugated nanobubbles (cy5.5-nanobubbles) of a biocompatible chitosan–vitamin C lipid system as a dual ultrasound-fluorescence contrast agent that achieved tumor-selective imaging in a mouse tumor model. Cy5.5-nanobubble suspension contained single bubble spheres and clusters of bubble spheres with the size ranging between 400–800 nm. In the in vivo mouse study, enhancement of ultrasound signals at tumor site was found to persist over 2 h while tumor-selective fluorescence emission was persistently observed over 24 h with intravenous injection of cy5.5-nanobubbles. In vitro cell study indicated that cy5.5-flurescence dye was able to accumulate in cancer cells due to the unique conjugated nanobubble structure. Further in vivo fluorescence study suggested that cy5.5-nanobubbles were mainly located at tumor site and in the bladder of mice. Subsequent analysis confirmed that accumulation of high fluorescence was present at the intact subcutaneous tumor site and in isolated tumor tissue but not in liver tissue post intravenous injection of cy5.5-nanobubbles. All these results led to the conclusion that cy5.5-nanobubbles with unique crosslinked chitosan–vitamin C lipid system have achieved tumor-selective imaging in vivo. PMID:23637799

Cyanine 5.5 conjugated nanobubbles as a tumor selective contrast agent for dual ultrasound-fluorescence imaging in a mouse model.

PubMed

Mai, Liyi; Yao, Anna; Li, Jing; Wei, Qiong; Yuchi, Ming; He, Xiaoling; Ding, Mingyue; Zhou, Qibing

2013-01-01

Nanobubbles and microbubbles are non-invasive ultrasound imaging contrast agents that may potentially enhance diagnosis of tumors. However, to date, both nanobubbles and microbubbles display poor in vivo tumor-selectivity over non-targeted organs such as liver. We report here cyanine 5.5 conjugated nanobubbles (cy5.5-nanobubbles) of a biocompatible chitosan-vitamin C lipid system as a dual ultrasound-fluorescence contrast agent that achieved tumor-selective imaging in a mouse tumor model. Cy5.5-nanobubble suspension contained single bubble spheres and clusters of bubble spheres with the size ranging between 400-800 nm. In the in vivo mouse study, enhancement of ultrasound signals at tumor site was found to persist over 2 h while tumor-selective fluorescence emission was persistently observed over 24 h with intravenous injection of cy5.5-nanobubbles. In vitro cell study indicated that cy5.5-flurescence dye was able to accumulate in cancer cells due to the unique conjugated nanobubble structure. Further in vivo fluorescence study suggested that cy5.5-nanobubbles were mainly located at tumor site and in the bladder of mice. Subsequent analysis confirmed that accumulation of high fluorescence was present at the intact subcutaneous tumor site and in isolated tumor tissue but not in liver tissue post intravenous injection of cy5.5-nanobubbles. All these results led to the conclusion that cy5.5-nanobubbles with unique crosslinked chitosan-vitamin C lipid system have achieved tumor-selective imaging in vivo.

Immunological characteristics and response to lipopolysaccharide of mouse lines selectively bred with natural and acquired immunities.

PubMed

Narahara, Hiroki; Sakai, Eri; Katayama, Masafumi; Ohtomo, Yukiko; Yamamoto, Kanako; Takemoto, Miki; Aso, Hisashi; Ohwada, Shyuichi; Mohri, Yasuaki; Nishimori, Katsuhiko; Isogai, Emiko; Yamaguchi, Takahiro; Fukuda, Tomokazu

2012-05-01

Genetic improvement of resistance to infectious diseases is a challenging goal in animal breeding. Infection resistance involves multiple immunological characteristics, including natural and acquired immunity. In the present study, we developed an experimental model based on genetic selection, to improve immunological phenotypes. We selectively established three mouse lines based on phagocytic activity, antibody production and the combination of these two phenotypes. We analyzed the immunological characteristics of these lines using a lipopolysaccharide (LPS), which is one of the main components of Gram-negative bacteria. An intense immunological reaction was induced in each of the three mouse lines. Severe loss of body weight and liver damage were observed, and a high level of cytokine messenger RNA was detected in the liver tissue. The mouse line established using a combination of the two selection standards showed unique characteristics relative to the mouse lines selected on the basis of a single phenotype. Our results indicate that genetic selection and breeding is effective, even for immunological phenotypes with a relatively low heritability. Thus, it may be possible to improve resistance to infectious diseases by means of genetic selection. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

Mouse vocal communication system: are ultrasounds learned or innate?

PubMed Central

Arriaga, Gustavo; Jarvis, Erich D.

2013-01-01

Mouse ultrasonic vocalizations (USVs) are often used as behavioral readouts of internal states, to measure effects of social and pharmacological manipulations, and for behavioral phenotyping of mouse models for neuropsychiatric and neurodegenerative disorders. However, little is known about the neurobiological mechanisms of rodent USV production. Here we discuss the available data to assess whether male mouse song behavior and the supporting brain circuits resemble those of known vocal non-learning or vocal learning species. Recent neurobiology studies have demonstrated that the mouse USV brain system includes motor cortex and striatal regions, and that the vocal motor cortex sends a direct sparse projection to the brainstem vocal motor nucleus ambiguous, a projection thought be unique to humans among mammals. Recent behavioral studies have reported opposing conclusions on mouse vocal plasticity, including vocal ontogeny changes in USVs over early development that might not be explained by innate maturation processes, evidence for and against a role for auditory feedback in developing and maintaining normal mouse USVs, and evidence for and against limited vocal imitation of song pitch. To reconcile these findings, we suggest that the trait of vocal learning may not be dichotomous but encompass a broad set of behavioral and neural traits we call the continuum hypothesis, and that mice possess some of the traits associated with a capacity for limited vocal learning. PMID:23295209

Use of Humanized Mice to Study the Pathogenesis of Autoimmune and Inflammatory Diseases

PubMed Central

Koboziev, Iurii; Jones-Hall, Yava; Valentine, John F.; Webb, Cynthia Reinoso; Furr, Kathryn L.; Grisham, Matthew B.

2015-01-01

Animal models of disease have been used extensively by the research community for the past several decades to better understand the pathogenesis of different diseases as well as assess the efficacy and toxicity of different therapeutic agents. Retrospective analyses of numerous preclinical intervention studies using mouse models of acute and chronic inflammatory diseases reveal a generalized failure to translate promising interventions or therapeutics into clinically-effective treatments in patients. Although several possible reasons have been suggested to account for this generalized failure to translate therapeutic efficacy from the laboratory bench to the patient’s bedside, it is becoming increasingly apparent that the mouse immune system may not adequately recapitulate the immuno-pathological mechanisms observed in human diseases. Indeed, it is well-known that >80 major differences exist between mouse and human immunology; all of which contribute to significant differences in immune system development, activation and responses to challenges in innate and adaptive immunity. This inconvenient reality has prompted investigators to attempt to humanize the mouse immune system in order to address important, human-specific questions that are impossible to study in patients. The successful long-term engraftment of human hemato-lymphoid cells in mice would provide investigators with a relatively inexpensive, small animal model to study clinically-relevant mechanisms as well as facilitate the evaluation of human-specific therapies in vivo. The discovery that targeted mutation of the IL-2 receptor common gamma chain in lymphopenic mice allows for the long-term engraftment of functional human immune cells has advanced greatly our ability to humanize the mouse immune system. The objective of this review is to present a brief overview of the recent advances that have been made in the development and use of humanized mice with special emphasis on autoimmune and chronic inflammatory diseases. In addition, we discuss current challenges and possible solutions for utilizing these unique mouse models to define the human-specific immuno-pathological mechanisms responsible for the induction and perpetuation of chronic gut inflammation. PMID:26035036

Agglutinating mouse IgG3 compares favourably with IgMs in typing of the blood group B antigen: Functionality and stability studies

PubMed Central

Klaus, Tomasz; Bzowska, Monika; Kulesza, Małgorzata; Kabat, Agnieszka Martyna; Jemioła-Rzemińska, Małgorzata; Czaplicki, Dominik; Makuch, Krzysztof; Jucha, Jarosław; Karabasz, Alicja; Bereta, Joanna

2016-01-01

Mouse immunoglobulins M (IgMs) that recognize human blood group antigens induce haemagglutination and are used worldwide for diagnostic blood typing. Contrary to the current belief that IgGs are too small to simultaneously bind antigens on two different erythrocytes, we obtained agglutinating mouse IgG3 that recognized antigen B of the human ABO blood group system. Mouse IgG3 is an intriguing isotype that has the ability to form Fc-dependent oligomers. However, F(ab′)2 fragments of the IgG3 were sufficient to agglutinate type B red blood cells; therefore, IgG3-triggered agglutination did not require oligomerization. Molecular modelling indicated that mouse IgG3 has a larger range of Fab arms than other mouse IgG subclasses and that the unique properties of mouse IgG3 are likely due to the structure of its hinge region. With a focus on applications in diagnostics, we compared the stability of IgG3 and two IgMs in formulated blood typing reagents using an accelerated storage approach and differential scanning calorimetry. IgG3 was much more stable than IgMs. Interestingly, the rapid decrease in IgM activity was caused by aggregation of the molecules and a previously unknown posttranslational proteolytic processing of the μ heavy chain. Our data point to mouse IgG3 as a potent diagnostic tool. PMID:27484487

A viscoelastic analysis of the P56 mouse brain under large-deformation dynamic indentation.

PubMed

MacManus, David B; Pierrat, Baptiste; Murphy, Jeremiah G; Gilchrist, Michael D

2017-01-15

The brain is a complex organ made up of many different functional and structural regions consisting of different types of cells such as neurons and glia, as well as complex anatomical geometries. It is hypothesized that the different regions of the brain exhibit significantly different mechanical properties which may be attributed to the diversity of cells within individual brain regions. The regional viscoelastic properties of P56 mouse brain tissue, up to 70μm displacement, are presented and discussed in the context of traumatic brain injury, particularly how the different regions of the brain respond to mechanical loads. Force-relaxation data obtained from micro-indentation measurements were fit to both linear and quasi-linear viscoelastic models to determine the time and frequency domain viscoelastic response of the pons, cortex, medulla oblongata, cerebellum, and thalamus. The damping ratio of each region was also determined. Each region was found to have a unique mechanical response to the applied displacement, with the pons and thalamus exhibiting the largest and smallest force-response, respectively. All brain regions appear to have an optimal frequency for the dissipation of energies which lies between 1 and 10Hz. We present the first mechanical characterization of the viscoelastic response for different regions of mouse brain. Force-relaxation tests are performed under large strain dynamic micro-indentation, and viscoelastic models are used subsequently, providing time-dependent mechanical properties of brain tissue under loading conditions comparable to what is experienced in TBI. The unique mechanical properties of different brain regions are highlighted, with substantial variations in the viscoelastic properties and damping ratio of each region. Cortex and pons were the stiffest regions, while the thalamus and medulla were most compliant. The cerebellum and thalamus had highest damping ratio values and those of the medulla were lowest. The reported material parameters can be implemented into finite element computer models of the mouse to investigate the effects of trauma on individual brain regions. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Cortical Spreading Depression Causes Unique Dysregulation of Inflammatory Pathways in a Transgenic Mouse Model of Migraine.

PubMed

Eising, Else; Shyti, Reinald; 't Hoen, Peter A C; Vijfhuizen, Lisanne S; Huisman, Sjoerd M H; Broos, Ludo A M; Mahfouz, Ahmed; Reinders, Marcel J T; Ferrari, Michel D; Tolner, Else A; de Vries, Boukje; van den Maagdenberg, Arn M J M

2017-05-01

Familial hemiplegic migraine type 1 (FHM1) is a rare monogenic subtype of migraine with aura caused by mutations in CACNA1A that encodes the α 1A subunit of voltage-gated Ca V 2.1 calcium channels. Transgenic knock-in mice that carry the human FHM1 R192Q missense mutation ('FHM1 R192Q mice') exhibit an increased susceptibility to cortical spreading depression (CSD), the mechanism underlying migraine aura. Here, we analysed gene expression profiles from isolated cortical tissue of FHM1 R192Q mice 24 h after experimentally induced CSD in order to identify molecular pathways affected by CSD. Gene expression profiles were generated using deep serial analysis of gene expression sequencing. Our data reveal a signature of inflammatory signalling upon CSD in the cortex of both mutant and wild-type mice. However, only in the brains of FHM1 R192Q mice specific genes are up-regulated in response to CSD that are implicated in interferon-related inflammatory signalling. Our findings show that CSD modulates inflammatory processes in both wild-type and mutant brains, but that an additional unique inflammatory signature becomes expressed after CSD in a relevant mouse model of migraine.

A Novel Small Molecule Modulator of Amyloid Pathology.

PubMed

Lovell, Mark A; Lynn, Bert C; Fister, Shuling; Bradley-Whitman, Melissa; Murphy, M Paul; Beckett, Tina L; Norris, Christopher M

2016-05-04

Because traditional approaches to drug development for Alzheimer's disease are becoming increasingly expensive and in many cases disappointingly unsuccessful, alternative approaches are required to shift the paradigm. Following leads from investigations of dihydropyridine calcium channel blockers, we observed unique properties from a class of functionalized naphthyridines and sought to develop these as novel therapeutics that minimize amyloid pathology without the adverse effects associated with current therapeutics. Our data show methyl 2,4-dimethyl-5-oxo-5,6-dihydrobenzo[c][2,7]naphthyridine-1-carboxylate (BNC-1) significantly decreases amyloid burden in a well-established mouse model of amyloid pathology through a unique mechanism mediated by Elk-1, a transcriptional repressor of presenilin-1. Additionally, BNC-1 treatment leads to increased levels of synaptophysin and synapsin, markers of synaptic integrity, but does not adversely impact presenilin-2 or processing of Notch-1, thus avoiding negative off target effects associated with pan-gamma secretase inhibition. Overall, our data show BNC-1 significantly decreases amyloid burden and improves markers of synaptic integrity in a well-established mouse model of amyloid deposition by promoting phosphorylation and activation of Elk-1, a transcriptional repressor of presenilin-1 but not presenilin-2. These data suggest BNC-1 might be a novel, disease-modifying therapeutic that will alter the pathogenesis of Alzheimer's disease.

Tissue phosphoproteomics with PolyMAC identifies potential therapeutic targets in a transgenic mouse model of HER2 positive breast cancer

PubMed Central

Searleman, Adam C.; Iliuk, Anton B.; Collier, Timothy S.; Chodosh, Lewis A.; Tao, W. Andy; Bose, Ron

2014-01-01

Altered protein phosphorylation is a feature of many human cancers that can be targeted therapeutically. Phosphopeptide enrichment is a critical step for maximizing the depth of phosphoproteome coverage by MS, but remains challenging for tissue specimens because of their high complexity. We describe the first analysis of a tissue phosphoproteome using polymer-based metal ion affinity capture (PolyMAC), a nanopolymer that has excellent yield and specificity for phosphopeptide enrichment, on a transgenic mouse model of HER2-driven breast cancer. By combining phosphotyrosine immunoprecipitation with PolyMAC, 411 unique peptides with 139 phosphotyrosine, 45 phosphoserine, and 29 phosphothreonine sites were identified from five LC-MS/MS runs. Combining reverse phase liquid chromatography fractionation at pH 8.0 with PolyMAC identified 1571 unique peptides with 1279 phosphoserine, 213 phosphothreonine, and 21 phosphotyrosine sites from eight LC-MS/MS runs. Linear motif analysis indicated that many of the phosphosites correspond to well-known phosphorylation motifs. Analysis of the tyrosine phosphoproteome with the Drug Gene Interaction database uncovered a network of potential therapeutic targets centered on Src family kinases with inhibitors that are either FDA-approved or in clinical development. These results demonstrate that PolyMAC is well suited for phosphoproteomic analysis of tissue specimens. PMID:24723360

Monogenic Mouse Models of Autism Spectrum Disorders: Common Mechanisms and Missing Links

PubMed Central

Hulbert, Samuel W.; Jiang, Yong-hui

2016-01-01

Autism Spectrum Disorders (ASDs) present unique challenges in the fields of genetics and neurobiology because of the clinical and molecular heterogeneity underlying these disorders. Genetic mutations found in ASD patients provide opportunities to dissect the molecular and circuit mechanisms underlying autistic behaviors using animal models. Ongoing studies of genetically modified models have offered critical insight into possible common mechanisms arising from different mutations, but links between molecular abnormalities and behavioral phenotypes remain elusive. The challenges encountered in modeling autism in mice demand a new analytic paradigm that integrates behavioral analysis with circuit-level analysis in genetically modified models with strong construct validity. PMID:26733386

Multi-shot PROPELLER for high-field preclinical MRI

PubMed Central

Pandit, Prachi; Qi, Yi; Story, Jennifer; King, Kevin F.; Johnson, G. Allan

2012-01-01

With the development of numerous mouse models of cancer, there is a tremendous need for an appropriate imaging technique to study the disease evolution. High-field T2-weighted imaging using PROPELLER MRI meets this need. The 2-shot PROPELLER technique presented here, provides (a) high spatial resolution, (b) high contrast resolution, and (c) rapid and non-invasive imaging, which enables high-throughput, longitudinal studies in free-breathing mice. Unique data collection and reconstruction makes this method robust against motion artifacts. The 2-shot modification introduced here, retains more high-frequency information and provides higher SNR than conventional single-shot PROPELLER, making this sequence feasible at high-fields, where signal loss is rapid. Results are shown in a liver metastases model to demonstrate the utility of this technique in one of the more challenging regions of the mouse, which is the abdomen. PMID:20572138

Multishot PROPELLER for high-field preclinical MRI.

PubMed

Pandit, Prachi; Qi, Yi; Story, Jennifer; King, Kevin F; Johnson, G Allan

2010-07-01

With the development of numerous mouse models of cancer, there is a tremendous need for an appropriate imaging technique to study the disease evolution. High-field T(2)-weighted imaging using PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) MRI meets this need. The two-shot PROPELLER technique presented here provides (a) high spatial resolution, (b) high contrast resolution, and (c) rapid and noninvasive imaging, which enables high-throughput, longitudinal studies in free-breathing mice. Unique data collection and reconstruction makes this method robust against motion artifacts. The two-shot modification introduced here retains more high-frequency information and provides higher signal-to-noise ratio than conventional single-shot PROPELLER, making this sequence feasible at high fields, where signal loss is rapid. Results are shown in a liver metastases model to demonstrate the utility of this technique in one of the more challenging regions of the mouse, which is the abdomen. (c) 2010 Wiley-Liss, Inc.

Establishment of neurovascular congruency in the mouse whisker system by an independent patterning mechanism.

PubMed

Oh, Won-Jong; Gu, Chenghua

2013-10-16

Nerves and vessels often run parallel to one another, a phenomenon that reflects their functional interdependency. Previous studies have suggested that neurovascular congruency in planar tissues such as skin is established through a "one-patterns-the-other" model, in which either the nervous system or the vascular system precedes developmentally and then instructs the other system to form using its established architecture as a template. Here, we find that, in tissues with complex three-dimensional structures such as the mouse whisker system, neurovascular congruency does not follow the previous model but rather is established via a mechanism in which nerves and vessels are patterned independently. Given the diversity of neurovascular structures in different tissues, guidance signals emanating from a central organizer in the specific target tissue may act as an important mechanism to establish neurovascular congruency patterns that facilitate unique target tissue function. Copyright © 2013 Elsevier Inc. All rights reserved.

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.

Phenotypic screening of hepatocyte nuclear factor (HNF) 4-{gamma} receptor knockout mice

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

Gerdin, Anna Karin; Surve, Vikas V.; Joensson, Marie

2006-10-20

Using the mouse as a model organism in pharmaceutical research presents unique advantages as its physiology in many ways resembles the human physiology, it also has a relatively short generation time, low breeding and maintenance costs, and is available in a wide variety of inbred strains. The ability to genetically modify mouse embryonic stem cells to generate mouse models that better mimic human disease is another advantage. In the present study, a comprehensive phenotypic screening protocol is applied to elucidate the phenotype of a novel mouse knockout model of hepatocyte nuclear factor (HNF) 4-{gamma}. HNF4-{gamma} is expressed in the kidneys,more » gut, pancreas, and testis. First level of the screen is aimed at general health, morphologic appearance, normal cage behaviour, and gross neurological functions. The second level of the screen looks at metabolic characteristics and lung function. The third level of the screen investigates behaviour more in-depth and the fourth level consists of a thorough pathological characterisation, blood chemistry, haematology, and bone marrow analysis. When compared with littermate wild-type mice (HNF4-{gamma}{sup +/+}), the HNF4-{gamma} knockout (HNF4-{gamma}{sup -/-}) mice had lowered energy expenditure and locomotor activity during night time that resulted in a higher body weight despite having reduced intake of food and water. HNF4-{gamma}{sup -/-} mice were less inclined to build nest and were found to spend more time in a passive state during the forced swim test.« less

Recommended nomenclature for five mammalian carboxylesterase gene families: human, mouse, and rat genes and proteins.

PubMed

Holmes, Roger S; Wright, Matthew W; Laulederkind, Stanley J F; Cox, Laura A; Hosokawa, Masakiyo; Imai, Teruko; Ishibashi, Shun; Lehner, Richard; Miyazaki, Masao; Perkins, Everett J; Potter, Phillip M; Redinbo, Matthew R; Robert, Jacques; Satoh, Tetsuo; Yamashita, Tetsuro; Yan, Bingfan; Yokoi, Tsuyoshi; Zechner, Rudolf; Maltais, Lois J

2010-10-01

Mammalian carboxylesterase (CES or Ces) genes encode enzymes that participate in xenobiotic, drug, and lipid metabolism in the body and are members of at least five gene families. Tandem duplications have added more genes for some families, particularly for mouse and rat genomes, which has caused confusion in naming rodent Ces genes. This article describes a new nomenclature system for human, mouse, and rat carboxylesterase genes that identifies homolog gene families and allocates a unique name for each gene. The guidelines of human, mouse, and rat gene nomenclature committees were followed and "CES" (human) and "Ces" (mouse and rat) root symbols were used followed by the family number (e.g., human CES1). Where multiple genes were identified for a family or where a clash occurred with an existing gene name, a letter was added (e.g., human CES4A; mouse and rat Ces1a) that reflected gene relatedness among rodent species (e.g., mouse and rat Ces1a). Pseudogenes were named by adding "P" and a number to the human gene name (e.g., human CES1P1) or by using a new letter followed by ps for mouse and rat Ces pseudogenes (e.g., Ces2d-ps). Gene transcript isoforms were named by adding the GenBank accession ID to the gene symbol (e.g., human CES1_AB119995 or mouse Ces1e_BC019208). This nomenclature improves our understanding of human, mouse, and rat CES/Ces gene families and facilitates research into the structure, function, and evolution of these gene families. It also serves as a model for naming CES genes from other mammalian species.

Functional characterization of mouse spinal cord infiltrating CD8+ lymphocytes

PubMed Central

Deb, Chandra; Howe, Charles L

2011-01-01

Understanding the immunopathogenesis of neuroimmunological diseases of the CNS requires a robust method for isolating and characterizing the immune effector cells that infiltrate the spinal cord in animal models. We have developed a simple and rapid isolation method that produces high yields of spinal cord infiltrating leukocytes from a single demyelinated spinal cord and which maintains high surface expression of key immunophenotyping antigens. Using this method and the Theiler’s virus model of chronic demyelination, we report the presence of spinal cord infiltrating acute effector CD8+ lymphocytes that are CD45hiCD44loCD62L− and a population of spinal cord infiltrating target effector memory CD8+ lymphocytes that are CD45hiCD44hiCD62L−. These cells respond robustly to ex vivo stimulation by producing interferon γ but do not exhibit specificity for Theiler’s virus in a cytotoxicity assay. We conclude that target-derived lymphocytes in a mouse model of chronic spinal cord demyelination may have unique functional specificities. PMID:19596449

Unique quadruple immunofluorescence assay demonstrates mitochondrial respiratory chain dysfunction in osteoblasts of aged and PolgA(-/-) mice.

PubMed

Dobson, Philip F; Rocha, Mariana C; Grady, John P; Chrysostomou, Alexia; Hipps, Daniel; Watson, Sharon; Greaves, Laura C; Deehan, David J; Turnbull, Doug M

2016-08-24

Fragility fractures caused by osteoporosis affect millions of people worldwide every year with significant levels of associated morbidity, mortality and costs to the healthcare economy. The pathogenesis of declining bone mineral density is poorly understood but it is inherently related to increasing age. Growing evidence in recent years, especially that provided by mouse models, suggest that accumulating somatic mitochondrial DNA mutations may cause the phenotypic changes associated with the ageing process including osteoporosis. Methods to study mitochondrial abnormalities in individual osteoblasts, osteoclasts and osteocytes are limited and impair our ability to assess the changes seen with age and in animal models of ageing. To enable the assessment of mitochondrial protein levels, we have developed a quadruple immunofluorescence method to accurately quantify the presence of mitochondrial respiratory chain components within individual bone cells. We have applied this technique to a well-established mouse model of ageing and osteoporosis and show respiratory chain deficiency.

Assessing Autism-like Behavior in Mice: Variations in Social Interactions Among Inbred Strains.

PubMed Central

Bolivar, Valerie J.; Walters, Samantha R.; Phoenix, Jennifer L.

2007-01-01

Autism is a pervasive developmental disorder, with characteristics including impairments in reciprocal social interaction, impaired communication, and repetitive/stereotyped behaviors. Despite decades of research, the etiology of autism remains elusive. Thus, it is important that we pursue all avenues, in attempting to understand this complicated disorder. One such avenue is the development of animal models. While autism may be uniquely human, there are behavioral characteristics of the disorder that can be established in animal models. Evidence supports a genetic component for this disorder, and over the past few decades the mouse has been a highly valuable tool for the elucidation of pathways involved in many human disorders (e.g., Huntington’s disease). As a first step toward establishing a mouse model of autism, we studied same-sex social behavior in a number of inbred mouse strains. In Study 1, we examined intra-strain social behavior of male pairs after one mouse had 15 minutes prior exposure to the testing chamber. In Study 2, we evaluated intra-strain and inter-strain social behavior when both mice were naive to the testing chamber. The amount and type of social behavior seen differed between these studies, but overall there were general inbred strain differences in social behavior. Some strains were highly social (e.g., FVB/NJ, while others displayed low levels of social behavior (e.g., A/J, BTBR T+ tf/J). These strains may be useful in future genetic studies to determine specific genes involved in mouse social behavior, the findings of which should in turn help us to determine some of the genes involved in human social behavior and its disorders (e.g., autism). PMID:17097158

Comparison of MeHg-induced toxicogenomic responses across in vivo and in vitro models used in developmental toxicology.

PubMed

Robinson, Joshua F; Theunissen, Peter T; van Dartel, Dorien A M; Pennings, Jeroen L; Faustman, Elaine M; Piersma, Aldert H

2011-09-01

Toxicogenomic evaluations may improve toxicity prediction of in vitro-based developmental models, such as whole embryo culture (WEC) and embryonic stem cells (ESC), by providing a robust mechanistic marker which can be linked with responses associated with developmental toxicity in vivo. While promising in theory, toxicogenomic comparisons between in vivo and in vitro models are complex due to inherent differences in model characteristics and experimental design. Determining factors which influence these global comparisons are critical in the identification of reliable mechanistic-based markers of developmental toxicity. In this study, we compared available toxicogenomic data assessing the impact of the known teratogen, methylmercury (MeHg) across a diverse set of in vitro and in vivo models to investigate the impact of experimental variables (i.e. model, dose, time) on our comparative assessments. We evaluated common and unique aspects at both the functional (Gene Ontology) and gene level of MeHg-induced response. At the functional level, we observed stronger similarity in MeHg-response between mouse embryos exposed in utero (2 studies), ESC, and WEC as compared to liver, brain and mouse embryonic fibroblast MeHg studies. These findings were strongly correlated to the presence of a MeHg-induced developmentally related gene signature. In addition, we identified specific MeHg-induced gene expression alterations associated with developmental signaling and heart development across WEC, ESC and in vivo systems. However, the significance of overlap between studies was highly dependent on traditional experimental variables (i.e. dose, time). In summary, we identify promising examples of unique gene expression responses which show in vitro-in vivo similarities supporting the relevance of in vitro developmental models for predicting in vivo developmental toxicity. Copyright © 2011 Elsevier Inc. All rights reserved.

β oscillation during slow wave sleep and rapid eye movement sleep in the electroencephalogram of a transgenic mouse model of Huntington's disease.

PubMed

Jeantet, Yannick; Cayzac, Sebastien; Cho, Yoon H

2013-01-01

To search for early abnormalities in electroencephalogram (EEG) during sleep which may precede motor symptoms in a transgenic mouse model of hereditary neurodegenerative Huntington's disease (HD). In the R6/1 transgenic mouse model of HD, rhythmic brain activity in EEG recordings was monitored longitudinally and across vigilance states through the onset and progression of disease. Mice with chronic electrode implants were recorded monthly over wake-sleep cycles (4 hours), beginning at 9-11 weeks (presymptomatic period) through 6-7 months (symptomatic period). Recording data revealed a unique β rhythm (20-35 Hz), present only in R6/1 transgenic mice, which evolves in close parallel with the disease. In addition, there was an unusual relationship between this β oscillation and vigilance states: while nearly absent during the active waking state, the β oscillation appeared with drowsiness and during slow wave sleep (SWS) and, interestingly, strengthened rather than dissipating when the brain returned to an activated state during rapid eye movement (REM) sleep. In addition to providing a new in vivo biomarker and insight into Huntington's disease pathophysiology, this serendipitous observation opens a window onto the rarely explored neurophysiology of the cortico-basal ganglia circuit during SWS and REM sleep.

A CTRP5 gene S163R mutation knock-in mouse model for late-onset retinal degeneration.

PubMed

Chavali, Venkata R M; Khan, Naheed W; Cukras, Catherine A; Bartsch, Dirk-Uwe; Jablonski, Monica M; Ayyagari, Radha

2011-05-15

Late-onset retinal macular degeneration (L-ORD) is an autosomal dominant inherited disorder caused by a single missense mutation (S163R) in the CTRP5/C1QTNF5 protein. Early phenotypic features of L-ORD include: dark adaptation abnormalities, nyctalopia, and drusen deposits in the peripheral macular region. Apart from posterior segment abnormalities, these patients also develop abnormally long anterior lens zonules. In the sixth decade of life the rod and cone function declines, accompanied by electroretinogram (ERG) abnormalities. Some patients also develop choroidal neovascularization and glaucoma. In order to understand the disease pathology and mechanisms involved in retinal dystrophy, we generated a knock-in (Ctrp5(+/-)) mouse model carrying the disease-associated mutation in the mouse Ctrp5/C1QTNF5 gene. These mice develop slower rod-b wave recovery consistent with early dark adaptation abnormalities, accumulation of hyperautofluorescence spots, retinal pigment epithelium abnormalities, drusen, Bruch's membrane abnormalities, loss of photoreceptors, and retinal vascular leakage. The Ctrp5(+/-) mice, which have most of the pathological features of age-related macular degeneration, are unique and may serve as a valuable model both to understand the molecular pathology of late-onset retinal degeneration and to evaluate therapies.

A CTRP5 gene S163R mutation knock-in mouse model for late-onset retinal degeneration

PubMed Central

Chavali, Venkata R.M.; Khan, Naheed W.; Cukras, Catherine A.; Bartsch, Dirk-Uwe; Jablonski, Monica M.; Ayyagari, Radha

2011-01-01

Late-onset retinal macular degeneration (L-ORD) is an autosomal dominant inherited disorder caused by a single missense mutation (S163R) in the CTRP5/C1QTNF5 protein. Early phenotypic features of L-ORD include: dark adaptation abnormalities, nyctalopia, and drusen deposits in the peripheral macular region. Apart from posterior segment abnormalities, these patients also develop abnormally long anterior lens zonules. In the sixth decade of life the rod and cone function declines, accompanied by electroretinogram (ERG) abnormalities. Some patients also develop choroidal neovascularization and glaucoma. In order to understand the disease pathology and mechanisms involved in retinal dystrophy, we generated a knock-in (Ctrp5+/−) mouse model carrying the disease-associated mutation in the mouse Ctrp5/C1QTNF5 gene. These mice develop slower rod-b wave recovery consistent with early dark adaptation abnormalities, accumulation of hyperautofluorescence spots, retinal pigment epithelium abnormalities, drusen, Bruch's membrane abnormalities, loss of photoreceptors, and retinal vascular leakage. The Ctrp5+/−mice, which have most of the pathological features of age-related macular degeneration, are unique and may serve as a valuable model both to understand the molecular pathology of late-onset retinal degeneration and to evaluate therapies. PMID:21349921

Cerebellar Directed Optogenetic Intervention Inhibits Spontaneous Hippocampal Seizures in a Mouse Model of Temporal Lobe Epilepsy1 2

PubMed Central

Szabo, Gergely G.; Armstrong, Caren; Oijala, Mikko; Soltesz, Ivan

2014-01-01

Abstract Cover Figure Krook-Magnuson et al. report a bidirectional functional connectivity between the hippocampus and the cerebellum in a mouse model of temporal lobe epilepsy, and demonstrate that cerebellar directed on-demand optogenetic intervention can stop seizures recorded from the hippocampus. Temporal lobe epilepsy is often medically refractory and new targets for intervention are needed. We used a mouse model of temporal lobe epilepsy, on-line seizure detection, and responsive optogenetic intervention to investigate the potential for cerebellar control of spontaneous temporal lobe seizures. Cerebellar targeted intervention inhibited spontaneous temporal lobe seizures during the chronic phase of the disorder. We further report that the direction of modulation as well as the location of intervention within the cerebellum can affect the outcome of intervention. Specifically, on-demand optogenetic excitation or inhibition of parvalbumin-expressing neurons, including Purkinje cells, in the lateral or midline cerebellum results in a decrease in seizure duration. In contrast, a consistent reduction in spontaneous seizure frequency occurs uniquely with on-demand optogenetic excitation of the midline cerebellum, and was not seen with intervention directly targeting the hippocampal formation. These findings demonstrate that the cerebellum is a powerful modulator of temporal lobe epilepsy, and that intervention targeting the cerebellum as a potential therapy for epilepsy should be revisited. PMID:25599088

Cloning and characterization of the mouse XPAC gene.

PubMed Central

van Oostrom, C T; de Vries, A; Verbeek, S J; van Kreijl, C F; van Steeg, H

1994-01-01

Xeroderma Pigmentosum is a human disease, which is, among others, characterized by a high incidence of (sunlight induced) skin cancer, due to a defect in nucleotide excision repair (NER). The human DNA repair gene XPAC corrects this defect in cells isolated from Xeroderma Pigmentosum complementation group A (XP-A) patients. To enable the development of a transgenic mouse model for XP-A by gene targeting in embryonic stem cells, we cloned and characterized the mouse homologue of the XPAC gene. The mouse XPAC gene was found to consist of 6 exons, spanning approximately 21 kb. The nucleotide sequence of the exons is identical to that of the also cloned the mouse XPAC cDNA. Furthermore, the deduced amino acid sequence of the XPAC protein is the same as the one published previously by Tanaka et al. From CAT assay analysis, the promoter of the XPAC gene appeared to be located within 313 bp upstream of the assumed transcriptional start site. Like the promoters of other eukaryotic DNA repair genes (i.e. ERCC-1 and XPBC/ERCC-3), the mouse XPAC promoter region lacks classical promoter elements like TATA-, GC- and CAAT boxes. However, it contains an unique polypyrimidine-rich box, which is so far only found in genes encoding DNA repair enzymes. The function of this box in the regulation of transcription is still unclear. PMID:8127648

A Naturally Fluorescent Mgp Transgenic Mouse for Angiogenesis and Glaucoma Longitudinal Studies

PubMed Central

Asokan, Priyadarsini; Mitra, Rajendra N.; Periasamy, Ramesh; Han, Zongchao

2018-01-01

Purpose Our goal was to generate and characterize a new mouse model in which only angiogenesis- and glaucoma-relevant tissues would be naturally fluorescent. The Matrix Gla (MGP) gene is highly expressed in vascular smooth muscle cells (VSMC) and trabecular meshwork (TM). We sought to direct our Mgp-Cre.KI mouse recombinase to VSMC/TM cells to produce their longitudinal fluorescent profiles. Methods Homozygous Mgp-Cre.KI mice were crossed with Ai9 homozygous reporter mice harboring a loxP-flanked STOP cassette preventing transcription of a DsRed fluorescent protein (tdTomato). The F1 double-heterozygous (Mgp-tdTomato) was examined by direct fluorescence, whole mount, histology, and fundus photography. Custom-made filters had 554/23 emission and 609/54 exciter nanometer wavelengths. Proof of concept of the model's usefulness was conducted by inducing guided imaging laser burns. Evaluation of a vessel's leakage and proliferation was followed by noninvasive angiography. Results The Mgp-tdTomato mouse was viable, fertile, with normal IOP and ERG. Its phenotype exhibited red paws and snout (cartilage expression), which precluded genotyping. A fluorescent red ring was seen at the limbus and confirmed to be TM expression by histology. The entire retinal vasculature was red fluorescent (VSMC) and directly visualized by fundus photography. Laser burns on the Mgp-tdTomato allowed separation of leakiness and neovascularization evaluation parameters. Conclusions The availability of a transgenic mouse naturally fluorescent in glaucoma-relevant tissues and retinal vasculature brings the unique opportunity to study a wide spectrum of single and combined glaucomatous conditions in vivo. Moreover, the Mgp-tdTomato mouse provides a new tool to study mechanisms and therapeutics of retinal angiogenesis longitudinally. PMID:29392320

A Naturally Fluorescent Mgp Transgenic Mouse for Angiogenesis and Glaucoma Longitudinal Studies.

PubMed

Asokan, Priyadarsini; Mitra, Rajendra N; Periasamy, Ramesh; Han, Zongchao; Borrás, Teresa

2018-02-01

Our goal was to generate and characterize a new mouse model in which only angiogenesis- and glaucoma-relevant tissues would be naturally fluorescent. The Matrix Gla (MGP) gene is highly expressed in vascular smooth muscle cells (VSMC) and trabecular meshwork (TM). We sought to direct our Mgp-Cre.KI mouse recombinase to VSMC/TM cells to produce their longitudinal fluorescent profiles. Homozygous Mgp-Cre.KI mice were crossed with Ai9 homozygous reporter mice harboring a loxP-flanked STOP cassette preventing transcription of a DsRed fluorescent protein (tdTomato). The F1 double-heterozygous (Mgp-tdTomato) was examined by direct fluorescence, whole mount, histology, and fundus photography. Custom-made filters had 554/23 emission and 609/54 exciter nanometer wavelengths. Proof of concept of the model's usefulness was conducted by inducing guided imaging laser burns. Evaluation of a vessel's leakage and proliferation was followed by noninvasive angiography. The Mgp-tdTomato mouse was viable, fertile, with normal IOP and ERG. Its phenotype exhibited red paws and snout (cartilage expression), which precluded genotyping. A fluorescent red ring was seen at the limbus and confirmed to be TM expression by histology. The entire retinal vasculature was red fluorescent (VSMC) and directly visualized by fundus photography. Laser burns on the Mgp-tdTomato allowed separation of leakiness and neovascularization evaluation parameters. The availability of a transgenic mouse naturally fluorescent in glaucoma-relevant tissues and retinal vasculature brings the unique opportunity to study a wide spectrum of single and combined glaucomatous conditions in vivo. Moreover, the Mgp-tdTomato mouse provides a new tool to study mechanisms and therapeutics of retinal angiogenesis longitudinally.

Permeabilization of brain tissue in situ enables multiregion analysis of mitochondrial function in a single mouse brain.

PubMed

Herbst, Eric A F; Holloway, Graham P

2015-02-15

Mitochondrial function in the brain is traditionally assessed through analysing respiration in isolated mitochondria, a technique that possesses significant tissue and time requirements while also disrupting the cooperative mitochondrial reticulum. We permeabilized brain tissue in situ to permit analysis of mitochondrial respiration with the native mitochondrial morphology intact, removing the need for isolation time and minimizing tissue requirements to ∼2 mg wet weight. The permeabilized brain technique was validated against the traditional method of isolated mitochondria and was then further applied to assess regional variation in the mouse brain with ischaemia-reperfusion injuries. A transgenic mouse model overexpressing catalase within mitochondria was applied to show the contribution of mitochondrial reactive oxygen species to ischaemia-reperfusion injuries in different brain regions. This technique enhances the accessibility of addressing physiological questions in small brain regions and in applying transgenic mouse models to assess mechanisms regulating mitochondrial function in health and disease. Mitochondria function as the core energy providers in the brain and symptoms of neurodegenerative diseases are often attributed to their dysregulation. Assessing mitochondrial function is classically performed in isolated mitochondria; however, this process requires significant isolation time, demand for abundant tissue and disruption of the cooperative mitochondrial reticulum, all of which reduce reliability when attempting to assess in vivo mitochondrial bioenergetics. Here we introduce a method that advances the assessment of mitochondrial respiration in the brain by permeabilizing existing brain tissue to grant direct access to the mitochondrial reticulum in situ. The permeabilized brain preparation allows for instant analysis of mitochondrial function with unaltered mitochondrial morphology using significantly small sample sizes (∼2 mg), which permits the analysis of mitochondrial function in multiple subregions within a single mouse brain. Here this technique was applied to assess regional variation in brain mitochondrial function with acute ischaemia-reperfusion injuries and to determine the role of reactive oxygen species in exacerbating dysfunction through the application of a transgenic mouse model overexpressing catalase within mitochondria. Through creating accessibility to small regions for the investigation of mitochondrial function, the permeabilized brain preparation enhances the capacity for examining regional differences in mitochondrial regulation within the brain, as the majority of genetic models used for unique approaches exist in the mouse model. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

In Vivo Imaging of Immuno-Spin Trapped Radicals With Molecular Magnetic Resonance Imaging in a Diabetic Mouse Model

PubMed Central

Towner, Rheal A.; Smith, Nataliya; Saunders, Debra; Henderson, Michael; Downum, Kristen; Lupu, Florea; Silasi-Mansat, Robert; Ramirez, Dario C.; Gomez-Mejiba, Sandra E.; Bonini, Marcelo G.; Ehrenshaft, Marilyn; Mason, Ronald P.

2012-01-01

Oxidative stress plays a major role in diabetes. In vivo levels of membrane-bound radicals (MBRs) in a streptozotocin-induced diabetic mouse model were uniquely detected by combining molecular magnetic resonance imaging (mMRI) and immunotrapping techniques. An anti-DMPO (5,5-dimethyl-1-pyrroline N-oxide) antibody (Ab) covalently bound to an albumin (BSA)-Gd (gadolinium)-DTPA (diethylene triamine penta acetic acid)-biotin MRI contrast agent (anti-DMPO probe), and mMRI, were used to detect in vivo levels of DMPO-MBR adducts in kidneys, livers, and lungs of diabetic mice, after DMPO administration. Magnetic resonance signal intensities, which increase in the presence of a Gd-based molecular probe, were significantly higher within the livers, kidneys, and lungs of diabetic animals administered the anti-DMPO probe compared with controls. Fluorescence images validated the location of the anti-DMPO probe in excised tissues via conjugation of streptavidin-Cy3, which targeted the probe biotin moiety, and immunohistochemistry was used to validate the presence of DMPO adducts in diabetic mouse livers. This is the first report of noninvasively imaging in vivo levels of MBRs within any disease model. This method can be specifically applied toward diabetes models for in vivo assessment of free radical levels, providing an avenue to more fully understand the role of free radicals in diabetes. PMID:22698922

Female Presence and Estrous State Influence Mouse Ultrasonic Courtship Vocalizations

PubMed Central

Hanson, Jessica L.; Hurley, Laura M.

2012-01-01

The laboratory mouse is an emerging model for context-dependent vocal signaling and reception. Mouse ultrasonic vocalizations are robustly produced in social contexts. In adults, male vocalization during courtship has become a model of interest for signal-receiver interactions. These vocalizations can be grouped into syllable types that are consistently produced by different subspecies and strains of mice. Vocalizations are unique to individuals, vary across development, and depend on social housing conditions. The behavioral significance of different syllable types, including the contexts in which different vocalizations are made and the responses listeners have to different types of vocalizations, is not well understood. We examined the effect of female presence and estrous state on male vocalizations by exploring the use of syllable types and the parameters of syllables during courtship. We also explored correlations between vocalizations and other behaviors. These experimental manipulations produced four main findings: 1) vocalizations varied among males, 2) the production of USVs and an increase in the use of a specific syllable type were temporally related to mounting behavior, 3) the frequency (kHz), bandwidth, and duration of syllables produced by males were influenced by the estrous phase of female partners, and 4) syllable types changed when females were removed. These findings show that mouse ultrasonic courtship vocalizations are sensitive to changes in female phase and presence, further demonstrating the context-sensitivity of these calls. PMID:22815817

Homozygous KSR1 deletion attenuates morbidity but does not prevent tumor development in a mouse model of RAS-driven pancreatic cancer

PubMed Central

Germino, Elizabeth A.; Miller, Joseph P.; Diehl, Lauri; Durinck, Steffen; Modrusan, Zora; Miner, Jeffrey H.

2018-01-01

Given the frequency with which MAP kinase signaling is dysregulated in cancer, much effort has been focused on inhibiting RAS signaling for therapeutic benefit. KSR1, a pseudokinase that interacts with RAF, is a potential target; it was originally cloned in screens for suppressors of constitutively active RAS, and its deletion prevents RAS-mediated transformation of mouse embryonic fibroblasts. In this work, we used a genetically engineered mouse model of pancreatic cancer to assess whether KSR1 deletion would influence tumor development in the setting of oncogenic RAS. We found that Ksr1-/- mice on this background had a modest but significant improvement in all-cause morbidity compared to Ksr1+/+ and Ksr1+/- cohorts. Ksr1-/- mice, however, still developed tumors, and precursor pancreatic intraepithelial neoplastic (PanIN) lesions were detected within a similar timeframe compared to Ksr1+/+ mice. No significant differences in pERK expression or in proliferation were noted. RNA sequencing also did not reveal any unique genetic signature in Ksr1-/- tumors. Further studies will be needed to determine whether and in what settings KSR inhibition may be clinically useful. PMID:29596465

A locus on mouse Ch10 influences susceptibility to limbic seizure severity: fine mapping and in silico candidate gene analysis

PubMed Central

Winawer, Melodie R.; Klassen, Tara L.; Teed, Sarah; Shipman, Marissa; Leung, Emily H.; Palmer, Abraham A.

2014-01-01

Identification of genes contributing to mouse seizure susceptibility can reveal novel genes or pathways that provide insight into human epilepsy. Using mouse chromosome substitution strains and interval-specific congenic strains (ISCS), we previously identified an interval conferring pilocarpine-induced limbic seizure susceptibility on distal mouse Chromosome 10 (Ch10). We narrowed the region by generating subcongenics with smaller A/J Ch10 segments on a C57BL/6J (B6) background and tested them with pilocarpine. We also tested pilocarpine susceptible congenics for 6Hz ECT, another model of limbic seizure susceptibility, to determine whether the susceptibility locus might have a broad effect on neuronal hyperexcitability across more than one mode of limbic seizure induction. ISCS Line 1, which contained the distal 2.7 Mb segment from A/J (starting at rs29382217), was more susceptible to both pilocarpine and ECT. Line 2, which was a subcongenic of Line1 (starting at rs13480828), was not susceptible; thus defining a 1.0 Mb critical region that was unique to Line1. Bioinformatic approaches identified 52 human orthologues within the unique Line 1 susceptibility region, the majority syntenic to human Ch12. Applying an epilepsy network analysis of known and suspected excitability genes and examination of interstrain genomic and brain expression differences revealed novel candidates within the region. These include Stat2, which plays a role in hippocampal GABA receptor expression after status epilepticus, and novel candidates Pan2, Cdk2, Gls2, and Cs, which are involved in neural cell differentiation, cellular remodeling, and embryonic development. Our strategy may facilitate discovery of novel human epilepsy genes. PMID:24373497

Systems Biology-Based Identification of Mycobacterium tuberculosis Persistence Genes in Mouse Lungs

PubMed Central

Dutta, Noton K.; Bandyopadhyay, Nirmalya; Veeramani, Balaji; Lamichhane, Gyanu; Karakousis, Petros C.; Bader, Joel S.

2014-01-01

ABSTRACT Identifying Mycobacterium tuberculosis persistence genes is important for developing novel drugs to shorten the duration of tuberculosis (TB) treatment. We developed computational algorithms that predict M. tuberculosis genes required for long-term survival in mouse lungs. As the input, we used high-throughput M. tuberculosis mutant library screen data, mycobacterial global transcriptional profiles in mice and macrophages, and functional interaction networks. We selected 57 unique, genetically defined mutants (18 previously tested and 39 untested) to assess the predictive power of this approach in the murine model of TB infection. We observed a 6-fold enrichment in the predicted set of M. tuberculosis genes required for persistence in mouse lungs relative to randomly selected mutant pools. Our results also allowed us to reclassify several genes as required for M. tuberculosis persistence in vivo. Finally, the new results implicated additional high-priority candidate genes for testing. Experimental validation of computational predictions demonstrates the power of this systems biology approach for elucidating M. tuberculosis persistence genes. PMID:24549847

CGDSNPdb: a database resource for error-checked and imputed mouse SNPs.

PubMed

Hutchins, Lucie N; Ding, Yueming; Szatkiewicz, Jin P; Von Smith, Randy; Yang, Hyuna; de Villena, Fernando Pardo-Manuel; Churchill, Gary A; Graber, Joel H

2010-07-06

The Center for Genome Dynamics Single Nucleotide Polymorphism Database (CGDSNPdb) is an open-source value-added database with more than nine million mouse single nucleotide polymorphisms (SNPs), drawn from multiple sources, with genotypes assigned to multiple inbred strains of laboratory mice. All SNPs are checked for accuracy and annotated for properties specific to the SNP as well as those implied by changes to overlapping protein-coding genes. CGDSNPdb serves as the primary interface to two unique data sets, the 'imputed genotype resource' in which a Hidden Markov Model was used to assess local haplotypes and the most probable base assignment at several million genomic loci in tens of strains of mice, and the Affymetrix Mouse Diversity Genotyping Array, a high density microarray with over 600,000 SNPs and over 900,000 invariant genomic probes. CGDSNPdb is accessible online through either a web-based query tool or a MySQL public login. Database URL: http://cgd.jax.org/cgdsnpdb/

Glial pannexin1 contributes to tactile hypersensitivity in a mouse model of orofacial pain

PubMed Central

Hanstein, Regina; Hanani, Menachem; Scemes, Eliana; Spray, David C.

2016-01-01

Drug studies in animal models have implicated pannexin1 (Panx1) in various types of pain, including trigeminal hypersensitivity, neuropathic pain and migraine. However, the tested drugs have limited specificity and efficacy so that direct evidence for Panx1 contribution to pain has been lacking. We here show that tactile hypersensitivity is markedly attenuated by deletion of Panx1 in a mouse model of chronic orofacial pain; in this model, trigeminal ganglion Panx1 expression and function are markedly enhanced. Targeted deletion of Panx1 in GFAP-positive glia or in neurons revealed distinct effects. Panx1 deletion in GFAP-positive glia cells prevented hypersensitivity completely, whereas deletion of neuronal Panx1 reduced baseline sensitivity and the duration of hypersensitivity. In trigeminal ganglia with genetically encoded Ca2+ indicator in GFAP-positive glia or in neurons, both cell populations were found to be hyperactive and hyper-responsive to ATP. These novel findings reveal unique roles for GFAP-positive glial and neuronal Panx1 and describe new chronic pain targets for cell-type specific intervention in this often intractable disease. PMID:27910899

Misbehaving macrophages in the pathogenesis of psoriasis

PubMed Central

Clark, Rachael A.; Kupper, Thomas S.

2006-01-01

Psoriasis is a chronic inflammatory skin disease unique to humans. In this issue of the JCI, 2 studies of very different mouse models of psoriasis both report that macrophages play a key role in inducing psoriasis-like skin disease. Psoriasis is clearly a polygenic, inherited disease of uncontrolled cutaneous inflammation. The debate that currently rages in the field is whether psoriasis is a disease of autoreactive T cells or whether it reflects an intrinsic defect within the skin — or both. However, these questions have proven difficult to dissect using molecular genetic tools. In the current studies, the authors have used 2 different animal models to address the role of macrophages in disease pathogenesis: Wang et al. use a mouse model in which inflammation is T cell dependent, whereas the model used by Stratis et al. is T cell independent (see the related articles beginning on pages 2105 and 2094, respectively). Strikingly, both groups report an important contribution by macrophages, implying that macrophages can contribute to both epithelial-based and T cell–mediated pathways of inflammation. PMID:16886055

Model of pediatric pituitary hormone deficiency separates the endocrine and neural functions of the LHX3 transcription factor in vivo.

PubMed

Colvin, Stephanie C; Malik, Raleigh E; Showalter, Aaron D; Sloop, Kyle W; Rhodes, Simon J

2011-01-04

The etiology of most pediatric hormone deficiency diseases is poorly understood. Children with combined pituitary hormone deficiency (CPHD) have insufficient levels of multiple anterior pituitary hormones causing short stature, metabolic disease, pubertal failure, and often have associated nervous system symptoms. Mutations in developmental regulatory genes required for the specification of the hormone-secreting cell types of the pituitary gland underlie severe forms of CPHD. To better understand these diseases, we have created a unique mouse model of CPHD with a targeted knockin mutation (Lhx3 W227ter), which is a model for the human LHX3 W224ter disease. The LHX3 gene encodes a LIM-homeodomain transcription factor, which has essential roles in pituitary and nervous system development in mammals. The introduced premature termination codon results in deletion of the carboxyl terminal region of the LHX3 protein, which is critical for pituitary gene activation. Mice that lack all LHX3 function do not survive beyond birth. By contrast, the homozygous Lhx3 W227ter mice survive, but display marked dwarfism, thyroid disease, and female infertility. Importantly, the Lhx3 W227ter mice have no apparent nervous system deficits. The Lhx3 W227ter mouse model provides a unique array of hormone deficits and facilitates experimental approaches that are not feasible with human patients. These experiments demonstrate that the carboxyl terminus of the LHX3 transcription factor is not required for viability. More broadly, this study reveals that the in vivo actions of a transcription factor in different tissues are molecularly separable.

Axial elongation in mouse embryos involves mediolateral cell intercalation behavior in the paraxial mesoderm

NASA Astrophysics Data System (ADS)

Yen, WeiWei; Burdsal, Carol; Periasamy, Ammasi; Sutherland, Ann E.

2006-02-01

The cell mechanical and signaling pathways involved in gastrulation have been studied extensively in invertebrates and amphibians, such as Xenopus, and more recently in non-mammalian vertebrates such as zebrafish and chick. However, because culturing mouse embryos extra-utero is very difficult, this fundamental process has been least characterized in the mouse. As the primary mammalian model for genetics, biochemistry, and the study of human disease and birth defects, it is important to investigate how gastrulation proceeds in murine embryos. We have developed a method of using 4D multiphoton excitation microscopy and extra-utero culture to visualize and characterize the morphogenetic movements in mouse embryos dissected at 8.5 days of gestation. Cells are labeled by expression of an X chromosome-linked enhanced green fluorescent protein (EGFP) transgene. This method has provided a unique approach, where, for the first time, patterns of cell behavior in the notochord and surrounding paraxial mesoderm can be visualized and traced quantitatively. Our observations of mouse embryos reveal both distinct differences as well as striking similarities in patterned cell motility relative to other vertebrate models such as Xenopus, where axial extension is driven primarily by mediolateral oriented cell behaviors in the notochord and paraxial somitic mesoderm. Unlike Xenopus, the width of the mouse notochord remains the same between 4-somite stage and 8-somite stage embryos. This implies the mouse notochord plays a lesser role in driving axial extension compared to Xenopus, although intercalation may occur where the anterior region of the node becomes notochordal plate. In contrast, the width of mouse paraxial mesoderm narrows significantly during this period and cells within the paraxial mesoderm are both elongated and aligned perpendicular to the midline. In addition, these cells are observed to intercalate, consistent with a role for paraxial mesoderm in driving convergence and extension. These cell behaviors are similar to those characterized in the axial mesoderm of frog embryos during convergence and extension[1], and suggests that tissues may play different roles in axial elongation between the frog and the mouse.

Inverted light-sheet microscope for imaging mouse pre-implantation development.

PubMed

Strnad, Petr; Gunther, Stefan; Reichmann, Judith; Krzic, Uros; Balazs, Balint; de Medeiros, Gustavo; Norlin, Nils; Hiiragi, Takashi; Hufnagel, Lars; Ellenberg, Jan

2016-02-01

Despite its importance for understanding human infertility and congenital diseases, early mammalian development has remained inaccessible to in toto imaging. We developed an inverted light-sheet microscope that enabled us to image mouse embryos from zygote to blastocyst, computationally track all cells and reconstruct a complete lineage tree of mouse pre-implantation development. We used this unique data set to show that the first cell fate specification occurs at the 16-cell stage.

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.

Development of a novel pink-eyed dilution mouse model showing progressive darkening of the eyes and coat hair with aging

PubMed Central

ISHIKAWA, Akira; SUGIYAMA, Makoto; HONDO, Eiichi; KINOSHITA, Keiji; YAMAGISHI, Yuki

2015-01-01

Oca2p-cas (oculocutaneous albinism II; pink-eyed dilution castaneus) is a coat color mutant gene on mouse chromosome 7 that arose spontaneously in wild Mus musculus castaneus mice. Mice homozygous for Oca2p-cas usually exhibit pink eyes and gray coat hair on the non-agouti genetic background, and this ordinary phenotype remains unchanged throughout life. During breeding of a mixed strain carrying this gene on the C57BL/6J background, we discovered a novel spontaneous mutation that causes darkening of the eyes and coat hair with aging. In this study, we developed a novel mouse model showing this unique phenotype. Gross observations revealed that the pink eyes and gray coat hair of the novel mutant young mice became progressively darker in color by approximately 3 months after birth. Light and transmission-electron microscopic observations revealed a marked increase in melanin pigmentation of coat hair shafts and choroid of the eye in the novel mice compared to that in the ordinary mice. Sequence analysis of Oca2p-cas revealed a 4.1-kb deletion involving exons 15 and 16 of its wild-type gene. However, there was no sequence difference between the two types of mutant mice. Mating experiments suggested that the novel mutant phenotype was not inherited in a simple fashion, due to incomplete penetrance. The novel spontaneous mutant mouse is the first example of progressive hair darkening animals and is an essential animal model for understanding of the regulation mechanisms of melanin biosynthesis with aging. PMID:25739360

Development of a novel pink-eyed dilution mouse model showing progressive darkening of the eyes and coat hair with aging.

PubMed

Ishikawa, Akira; Sugiyama, Makoto; Hondo, Eiichi; Kinoshita, Keiji; Yamagishi, Yuki

2015-01-01

Oca2(p-cas) (oculocutaneous albinism II; pink-eyed dilution castaneus) is a coat color mutant gene on mouse chromosome 7 that arose spontaneously in wild Mus musculus castaneus mice. Mice homozygous for Oca2(p-cas) usually exhibit pink eyes and gray coat hair on the non-agouti genetic background, and this ordinary phenotype remains unchanged throughout life. During breeding of a mixed strain carrying this gene on the C57BL/6J background, we discovered a novel spontaneous mutation that causes darkening of the eyes and coat hair with aging. In this study, we developed a novel mouse model showing this unique phenotype. Gross observations revealed that the pink eyes and gray coat hair of the novel mutant young mice became progressively darker in color by approximately 3 months after birth. Light and transmission-electron microscopic observations revealed a marked increase in melanin pigmentation of coat hair shafts and choroid of the eye in the novel mice compared to that in the ordinary mice. Sequence analysis of Oca2(p-cas) revealed a 4.1-kb deletion involving exons 15 and 16 of its wild-type gene. However, there was no sequence difference between the two types of mutant mice. Mating experiments suggested that the novel mutant phenotype was not inherited in a simple fashion, due to incomplete penetrance. The novel spontaneous mutant mouse is the first example of progressive hair darkening animals and is an essential animal model for understanding of the regulation mechanisms of melanin biosynthesis with aging.

The nuclear import factor importin α4 can protect against oxidative stress.

PubMed

Young, Julia C; Ly-Huynh, Jennifer D; Lescesen, Helen; Miyamoto, Yoichi; Browne, Cate; Yoneda, Yoshihiro; Koopman, Peter; Loveland, Kate L; Jans, David A

2013-10-01

The importin (IMP) superfamily of nuclear transport proteins is essential to key developmental pathways, including in the murine testis where expression of the 6 distinct IMPα proteins is highly dynamic. Present predominantly from the spermatocyte stage onwards, IMPα4 is unique in showing a striking nuclear localization, a property we previously found to be linked to maintenance of pluripotency in embryonic stem cells and to the cellular stress response in cultured cells. Here we examine the role of IMPα4 in vivo for the first time using a novel transgenic mouse model in which we overexpress an IMPα4-EGFP fusion protein from the protamine 1 promoter to recapitulate endogenous testicular germ cell IMPα4 expression in spermatids. IMPα4 overexpression did not affect overall fertility, testis morphology/weight or spermatogenic progression under normal conditions, but conferred significantly (>30%) increased resistance to oxidative stress specifically in the spermatid subpopulation expressing the transgene. Consistent with a cell-specific role for IMPα4 in protecting against oxidative stress, haploid germ cells from IMPα4 null mice were significantly (c. 30%) less resistant to oxidative stress than wild type controls. These results from two unique and complementary mouse models demonstrate a novel protective role for IMPα4 in stress responses specifically within haploid male germline cells, with implications for male fertility and genetic integrity. Copyright © 2013 Elsevier B.V. All rights reserved.

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

Characterization of a transgenic short hairpin RNA-induced murine model of Tafazzin deficiency.

PubMed

Soustek, Meghan S; Falk, Darin J; Mah, Cathryn S; Toth, Matthew J; Schlame, Michael; Lewin, Alfred S; Byrne, Barry J

2011-07-01

Barth's syndrome (BTHS) is an X-linked mitochondrial disease that is due to a mutation in the Tafazzin (TAZ) gene. Based on sequence homology, TAZ has been characterized as an acyltransferase involved in the metabolism of cardiolipin (CL), a unique phospholipid almost exclusively located in the mitochondrial inner membrane. Yeast, Drosophila, and zebrafish models have been invaluable in elucidating the role of TAZ in BTHS, but until recently a mammalian model to study the disease has been lacking. Based on in vitro evidence of RNA-mediated TAZ depletion, an inducible short hairpin RNA (shRNA)-mediated TAZ knockdown (TAZKD) mouse model has been developed (TaconicArtemis GmbH, Cologne, Germany), and herein we describe the assessment of this mouse line as a model of BTHS. Upon induction of the TAZ-specific shRNA in vivo, transgenic mouse TAZ mRNA levels were reduced by >89% in cardiac and skeletal muscle. TAZ deficiency led to the absence of tetralineoyl-CL and accumulation of monolyso-CL in cardiac muscle. Furthermore, mitochondrial morphology from cardiac and skeletal muscle was altered. Skeletal muscle mitochondria demonstrated disrupted cristae, and cardiac mitochondria were significantly enlarged and displace neighboring myofibrils. Physiological measurements demonstrated a reduction in isometric contractile strength of the soleus and a reduction in cardiac left ventricular ejection fraction of TAZKD mice compared with control animals. Therefore, the inducible TAZ-deficient model exhibits some of the molecular and clinical characteristics of BTHS patients and may ultimately help to improve our understanding of BTHS-related cardioskeletal myopathy as well as serve as an important tool in developing therapeutic strategies for BTHS.

β Oscillation during Slow Wave Sleep and Rapid Eye Movement Sleep in the Electroencephalogram of a Transgenic Mouse Model of Huntington’s Disease

PubMed Central

Jeantet, Yannick; Cayzac, Sebastien; Cho, Yoon H.

2013-01-01

Study objectives To search for early abnormalities in electroencephalogram (EEG) during sleep which may precede motor symptoms in a transgenic mouse model of hereditary neurodegenerative Huntington’s disease (HD). Design In the R6/1 transgenic mouse model of HD, rhythmic brain activity in EEG recordings was monitored longitudinally and across vigilance states through the onset and progression of disease. Measurements and results Mice with chronic electrode implants were recorded monthly over wake-sleep cycles (4 hours), beginning at 9–11 weeks (presymptomatic period) through 6–7 months (symptomatic period). Recording data revealed a unique β rhythm (20–35 Hz), present only in R6/1 transgenic mice, which evolves in close parallel with the disease. In addition, there was an unusual relationship between this β oscillation and vigilance states: while nearly absent during the active waking state, the β oscillation appeared with drowsiness and during slow wave sleep (SWS) and, interestingly, strengthened rather than dissipating when the brain returned to an activated state during rapid eye movement (REM) sleep. Conclusions In addition to providing a new in vivo biomarker and insight into Huntington's disease pathophysiology, this serendipitous observation opens a window onto the rarely explored neurophysiology of the cortico-basal ganglia circuit during SWS and REM sleep. PMID:24244517

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.

Centella asiatica Extract Improves Behavioral Deficits in a Mouse Model of Alzheimer's Disease: Investigation of a Possible Mechanism of Action

PubMed Central

Soumyanath, Amala; Zhong, Yong-Ping; Henson, Edward; Wadsworth, Teri; Bishop, James; Gold, Bruce G.; Quinn, Joseph F.

2012-01-01

Centella asiatica (CA), commonly named gotu kola, is an Ayurvedic herb used to enhance memory and nerve function. To investigate the potential use of CA in Alzheimer's disease (AD), we examined the effects of a water extract of CA (GKW) in the Tg2576 mouse, a murine model of AD with high β-amyloid burden. Orally administered GKW attenuated β-amyloid-associated behavioral abnormalities in these mice. In vitro, GKW protected SH-SY5Y cells and MC65 human neuroblastoma cells from toxicity induced by exogenously added and endogenously generated β-amyloid, respectively. GKW prevented intracellular β-amyloid aggregate formation in MC65 cells. GKW did not show anticholinesterase activity or protect neurons from oxidative damage and glutamate toxicity, mechanisms of current AD therapies. GKW is rich in phenolic compounds and does not contain asiatic acid, a known CA neuroprotective triterpene. CA thus offers a unique therapeutic mechanism and novel active compounds of potential relevance to the treatment of AD. PMID:22506133

Centella asiatica Extract Improves Behavioral Deficits in a Mouse Model of Alzheimer's Disease: Investigation of a Possible Mechanism of Action.

PubMed

Soumyanath, Amala; Zhong, Yong-Ping; Henson, Edward; Wadsworth, Teri; Bishop, James; Gold, Bruce G; Quinn, Joseph F

2012-01-01

Centella asiatica (CA), commonly named gotu kola, is an Ayurvedic herb used to enhance memory and nerve function. To investigate the potential use of CA in Alzheimer's disease (AD), we examined the effects of a water extract of CA (GKW) in the Tg2576 mouse, a murine model of AD with high β-amyloid burden. Orally administered GKW attenuated β-amyloid-associated behavioral abnormalities in these mice. In vitro, GKW protected SH-SY5Y cells and MC65 human neuroblastoma cells from toxicity induced by exogenously added and endogenously generated β-amyloid, respectively. GKW prevented intracellular β-amyloid aggregate formation in MC65 cells. GKW did not show anticholinesterase activity or protect neurons from oxidative damage and glutamate toxicity, mechanisms of current AD therapies. GKW is rich in phenolic compounds and does not contain asiatic acid, a known CA neuroprotective triterpene. CA thus offers a unique therapeutic mechanism and novel active compounds of potential relevance to the treatment of AD.

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

Oncogenic RAS pathway activation promotes resistance to anti-VEGF therapy through G-CSF–induced neutrophil recruitment

PubMed Central

Phan, Vernon T.; Wu, Xiumin; Cheng, Jason H.; Sheng, Rebecca X.; Chung, Alicia S.; Zhuang, Guanglei; Tran, Christopher; Song, Qinghua; Kowanetz, Marcin; Sambrone, Amy; Tan, Martha; Meng, Y. Gloria; Jackson, Erica L.; Peale, Franklin V.; Junttila, Melissa R.; Ferrara, Napoleone

2013-01-01

Granulocyte-colony stimulating factor (G-CSF) promotes mobilization of CD11b+Gr1+ myeloid cells and has been implicated in resistance to anti-VEGF therapy in mouse models. High G-CSF production has been associated with a poor prognosis in cancer patients. Here we show that activation of the RAS/MEK/ERK pathway regulates G-CSF expression through the Ets transcription factor. Several growth factors induced G-CSF expression by a MEK-dependent mechanism. Inhibition of G-CSF release with a MEK inhibitor markedly reduced G-CSF production in vitro and synergized with anti-VEGF antibodies to reduce CD11b+Ly6G+ neutrophil mobilization and tumor growth and led to increased survival in animal models of cancer, including a genetically engineered mouse model of pancreatic adenocarcinoma. Analysis of biopsies from pancreatic cancer patients revealed increased phospho-MEK, G-CSF, and Ets expression and enhanced neutrophil recruitment compared with normal pancreata. These results provide insights into G-CSF regulation and on the mechanism of action of MEK inhibitors and point to unique anticancer strategies. PMID:23530240

Mesothelioma: Identification of the Key Molecular Events Triggered by BAP1

DTIC Science & Technology

2014-09-01

amounts of asbestos that would normally not cause MM in the population at large. In order to study the mechanism(s), we assembled a unique cohort and...BAP1 status regulate NF-kB activity and HMGB1 release, and we also found that monoallelic BAP1 loss increases susceptibility to low doses of asbestos ...by using a mouse model. 15. SUBJECT TERMS mesothelioma, BAP1, asbestos , mechanisms 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18

Integration of Brain and Skull in Prenatal Mouse Models of Apert and Crouzon Syndromes

PubMed Central

Motch Perrine, Susan M.; Stecko, Tim; Neuberger, Thomas; Jabs, Ethylin W.; Ryan, Timothy M.; Richtsmeier, Joan T.

2017-01-01

The brain and skull represent a complex arrangement of integrated anatomical structures composed of various cell and tissue types that maintain structural and functional association throughout development. Morphological integration, a concept developed in vertebrate morphology and evolutionary biology, describes the coordinated variation of functionally and developmentally related traits of organisms. Syndromic craniosynostosis is characterized by distinctive changes in skull morphology and perceptible, though less well studied, changes in brain structure and morphology. Using mouse models for craniosynostosis conditions, our group has precisely defined how unique craniosynostosis causing mutations in fibroblast growth factor receptors affect brain and skull morphology and dysgenesis involving coordinated tissue-specific effects of these mutations. Here we examine integration of brain and skull in two mouse models for craniosynostosis: one carrying the FGFR2c C342Y mutation associated with Pfeiffer and Crouzon syndromes and a mouse model carrying the FGFR2 S252W mutation, one of two mutations responsible for two-thirds of Apert syndrome cases. Using linear distances estimated from three-dimensional coordinates of landmarks acquired from dual modality imaging of skull (high resolution micro-computed tomography and magnetic resonance microscopy) of mice at embryonic day 17.5, we confirm variation in brain and skull morphology in Fgfr2cC342Y/+ mice, Fgfr2+/S252W mice, and their unaffected littermates. Mutation-specific variation in neural and cranial tissue notwithstanding, patterns of integration of brain and skull differed only subtly between mice carrying either the FGFR2c C342Y or the FGFR2 S252W mutation and their unaffected littermates. However, statistically significant and substantial differences in morphological integration of brain and skull were revealed between the two mutant mouse models, each maintained on a different strain. Relative to the effects of disease-associated mutations, our results reveal a stronger influence of the background genome on patterns of brain-skull integration and suggest robust genetic, developmental, and evolutionary relationships between neural and skeletal tissues of the head. PMID:28790902

Murine but not human basophil undergoes cell-specific proteolysis of a major endoplasmic reticulum chaperone.

PubMed

Liu, Bei; Staron, Matthew; Li, Zihai

2012-01-01

Basophil has been implicated in anti-parasite defense, allergy and in polarizing T(H)2 response. Mouse model has been commonly used to study basophil function although the difference between human and mouse basophils is underappreciated. As an essential chaperone for multiple Toll-like receptors and integrins in the endoplasmic reticulum, gp96 also participates in general protein homeostasis and in the ER unfolded protein response to ensure cell survival during stress. The roles of gp96 in basophil development are unknown. We genetically delete gp96 in mice and examined the expression of gp96 in basophils by Western blot and flow cytometry. We compared the expression pattern of gp96 between human and mouse basophils. We found that gp96 was dispensable for murine basophil development. Moreover, gp96 was cleaved by serine protease(s) in murine but not human basophils leading to accumulation of a nun-functional N-terminal ∼50 kDa fragment and striking induction of the unfolded protein response. The alteration of gp96 was unique to basophils and was not observed in any other cell types including mast cells. We also demonstrated that the ectopic expression of a mouse-specific tryptase mMCP11 does not lead to gp96 cleavage in human basophils. Our study revealed a remarkable biochemical event of gp96 silencing in murine but not human basophils, highlighting the need for caution in using mouse models to infer the function of basophils in human immune response. Our study also reveals a novel mechanism of shutting down gp96 post-translationally in regulating its function.

A preclinical mouse model of invasive lobular breast cancer metastasis.

PubMed

Doornebal, Chris W; Klarenbeek, Sjoerd; Braumuller, Tanya M; Klijn, Christiaan N; Ciampricotti, Metamia; Hau, Cheei-Sing; Hollmann, Markus W; Jonkers, Jos; de Visser, Karin E

2013-01-01

Metastatic disease accounts for more than 90% of cancer-related deaths, but the development of effective antimetastatic agents has been hampered by the paucity of clinically relevant preclinical models of human metastatic disease. Here, we report the development of a mouse model of spontaneous breast cancer metastasis, which recapitulates key events in its formation and clinical course. Specifically, using the conditional K14cre;Cdh1(F/F);Trp53(F/F) model of de novo mammary tumor formation, we orthotopically transplanted invasive lobular carcinoma (mILC) fragments into mammary glands of wild-type syngeneic hosts. Once primary tumors were established in recipient mice, we mimicked the clinical course of treatment by conducting a mastectomy. After surgery, recipient mice succumbed to widespread overt metastatic disease in lymph nodes, lungs, and gastrointestinal tract. Genomic profiling of paired mammary tumors and distant metastases showed that our model provides a unique tool to further explore the biology of metastatic disease. Neoadjuvant and adjuvant intervention studies using standard-of-care chemotherapeutics showed the value of this model in determining therapeutic agents that can target early- and late-stage metastatic disease. In obtaining a more accurate preclinical model of metastatic lobular breast cancer, our work offers advances supporting the development of more effective treatment strategies for metastatic disease.

Motor and cognitive stereotypies in the BTBR T+tf/J mouse model of autism

PubMed Central

Pearson, BL; Pobbe, RLH; Defensor, EB; Oasay, L; Bolivar, VJ; Blanchard, DC; Blanchard, RJ

2010-01-01

The BTBR T+tf/J inbred mouse strain displays a variety of persistent phenotypic alterations similar to those exhibited in autism spectrum disorders. The unique genetic background of the BTBR strain is thought to underlie its lack of reciprocal social interactions, elevated repetitive self-directed grooming and restricted exploratory behaviors. In order to clarify the existence, range and mechanisms of abnormal repetitive behaviors within BTBR mice, we performed detailed analyses of the microstructure of self-grooming patterns and noted increased overall grooming, higher percentages of interruptions in grooming bouts and a concomitant decrease in the proportion of incorrect sequence transitions compared to C57BL/6J inbred mice. Analyses of active phase home cage behavior also revealed an increase in stereotypic bar-biting behavior in the BTBR strain relative to B6 mice. Finally, in a novel object investigation task, BTBR mice exhibited greater baseline preference for specific unfamiliar objects as well as more patterned sequences of sequential investigations of those items. These results suggest that the repetitive, stereotyped behavior patterns of BTBR mice are relatively pervasive and reflect both motor and cognitive mechanisms. Furthermore, other pre-clinical mouse models of autism spectrum disorders may benefit from these more detailed analyses of stereotypic behavior. PMID:21040460

Acid-Sensitive Sheddable PEGylated PLGA Nanoparticles Increase the Delivery of TNF-α siRNA in Chronic Inflammation Sites

PubMed Central

Aldayel, Abdulaziz M; Naguib, Youssef W; O'Mary, Hannah L; Li, Xu; Niu, Mengmeng; Ruwona, Tinashe B; Cui, Zhengrong

2016-01-01

There has been growing interest in utilizing small interfering RNA (siRNA) specific to pro-inflammatory cytokines, such as tumor necrosis factor-α ( TNF-α), in chronic inflammation therapy. However, delivery systems that can increase the distribution of the siRNA in chronic inflammation sites after intravenous administration are needed. Herein we report that innovative functionalization of the surface of siRNA-incorporated poly (lactic-co-glycolic) acid (PLGA) nanoparticles significantly increases the delivery of the siRNA in the chronic inflammation sites in a mouse model. The TNF-α siRNA incorporated PLGA nanoparticles were prepared by the standard double emulsion method, but using stearoyl-hydrazone-polyethylene glycol 2000, a unique acid-sensitive surface active agent, as the emulsifying agent, which renders (i) the nanoparticles PEGylated and (ii) the PEGylation sheddable in low pH environment such as that in chronic inflammation sites. In a mouse model of lipopolysaccharide-induced chronic inflammation, the acid-sensitive sheddable PEGylated PLGA nanoparticles showed significantly higher accumulation or distribution in chronic inflammation sites than PLGA nanoparticles prepared with an acid-insensitive emulsifying agent (i.e., stearoyl-amide-polyethylene glycol 2000) and significantly increased the distribution of the TNF-α siRNA incorporated into the nanoparticles in inflamed mouse foot. PMID:27434685

Developmental fate and lineage commitment of singled mouse blastomeres.

PubMed

Lorthongpanich, Chanchao; Doris, Tham Puay Yoke; Limviphuvadh, Vachiranee; Knowles, Barbara B; Solter, Davor

2012-10-01

The inside-outside model has been invoked to explain cell-fate specification of the pre-implantation mammalian embryo. Here, we investigate whether cell-cell interaction can influence the fate specification of embryonic blastomeres by sequentially separating the blastomeres in two-cell stage mouse embryos and continuing separation after each cell division throughout pre-implantation development. This procedure eliminates information provided by cell-cell interaction and cell positioning. Gene expression profiles, polarity protein localization and functional tests of these separated blastomeres reveal that cell interactions, through cell position, influence the fate of the blastomere. Blastomeres, in the absence of cell contact and inner-outer positional information, have a unique pattern of gene expression that is characteristic of neither inner cell mass nor trophectoderm, but overall they have a tendency towards a 'trophectoderm-like' gene expression pattern and preferentially contribute to the trophectoderm lineage.

High-Throughput, Signature-Tagged Mutagenic Approach To Identify Novel Virulence Factors of Yersinia pestis CO92 in a Mouse Model of Infection

PubMed Central

Ponnusamy, Duraisamy; Fitts, Eric C.; Erova, Tatiana E.; Kozlova, Elena V.; Kirtley, Michelle L.; Tiner, Bethany L.; Andersson, Jourdan A.

2015-01-01

The identification of new virulence factors in Yersinia pestis and understanding their molecular mechanisms during an infection process are necessary in designing a better vaccine or to formulate an appropriate therapeutic intervention. By using a high-throughput, signature-tagged mutagenic approach, we created 5,088 mutants of Y. pestis strain CO92 and screened them in a mouse model of pneumonic plague at a dose equivalent to 5 50% lethal doses (LD50) of wild-type (WT) CO92. From this screen, we obtained 118 clones showing impairment in disseminating to the spleen, based on hybridization of input versus output DNA from mutant pools with 53 unique signature tags. In the subsequent screen, 20/118 mutants exhibited attenuation at 8 LD50 when tested in a mouse model of bubonic plague, with infection by 10/20 of the aforementioned mutants resulting in 40% or higher survival rates at an infectious dose of 40 LD50. Upon sequencing, six of the attenuated mutants were found to carry interruptions in genes encoding hypothetical proteins or proteins with putative functions. Mutants with in-frame deletion mutations of two of the genes identified from the screen, namely, rbsA, which codes for a putative sugar transport system ATP-binding protein, and vasK, a component of the type VI secretion system, were also found to exhibit some attenuation at 11 or 12 LD50 in a mouse model of pneumonic plague. Likewise, among the remaining 18 signature-tagged mutants, 9 were also attenuated (40 to 100%) at 12 LD50 in a pneumonic plague mouse model. Previously, we found that deleting genes encoding Braun lipoprotein (Lpp) and acyltransferase (MsbB), the latter of which modifies lipopolysaccharide function, reduced the virulence of Y. pestis CO92 in mouse models of bubonic and pneumonic plague. Deletion of rbsA and vasK genes from either the Δlpp single or the Δlpp ΔmsbB double mutant augmented the attenuation to provide 90 to 100% survivability to mice in a pneumonic plague model at 20 to 50 LD50. The mice infected with the Δlpp ΔmsbB ΔrbsA triple mutant at 50 LD50 were 90% protected upon subsequent challenge with 12 LD50 of WT CO92, suggesting that this mutant or others carrying combinational deletions of genes identified through our screen could potentially be further tested and developed into a live attenuated plague vaccine(s). PMID:25754198

High-throughput, signature-tagged mutagenic approach to identify novel virulence factors of Yersinia pestis CO92 in a mouse model of infection.

PubMed

Ponnusamy, Duraisamy; Fitts, Eric C; Sha, Jian; Erova, Tatiana E; Kozlova, Elena V; Kirtley, Michelle L; Tiner, Bethany L; Andersson, Jourdan A; Chopra, Ashok K

2015-05-01

The identification of new virulence factors in Yersinia pestis and understanding their molecular mechanisms during an infection process are necessary in designing a better vaccine or to formulate an appropriate therapeutic intervention. By using a high-throughput, signature-tagged mutagenic approach, we created 5,088 mutants of Y. pestis strain CO92 and screened them in a mouse model of pneumonic plague at a dose equivalent to 5 50% lethal doses (LD50) of wild-type (WT) CO92. From this screen, we obtained 118 clones showing impairment in disseminating to the spleen, based on hybridization of input versus output DNA from mutant pools with 53 unique signature tags. In the subsequent screen, 20/118 mutants exhibited attenuation at 8 LD50 when tested in a mouse model of bubonic plague, with infection by 10/20 of the aforementioned mutants resulting in 40% or higher survival rates at an infectious dose of 40 LD50. Upon sequencing, six of the attenuated mutants were found to carry interruptions in genes encoding hypothetical proteins or proteins with putative functions. Mutants with in-frame deletion mutations of two of the genes identified from the screen, namely, rbsA, which codes for a putative sugar transport system ATP-binding protein, and vasK, a component of the type VI secretion system, were also found to exhibit some attenuation at 11 or 12 LD50 in a mouse model of pneumonic plague. Likewise, among the remaining 18 signature-tagged mutants, 9 were also attenuated (40 to 100%) at 12 LD50 in a pneumonic plague mouse model. Previously, we found that deleting genes encoding Braun lipoprotein (Lpp) and acyltransferase (MsbB), the latter of which modifies lipopolysaccharide function, reduced the virulence of Y. pestis CO92 in mouse models of bubonic and pneumonic plague. Deletion of rbsA and vasK genes from either the Δlpp single or the Δlpp ΔmsbB double mutant augmented the attenuation to provide 90 to 100% survivability to mice in a pneumonic plague model at 20 to 50 LD50. The mice infected with the Δlpp ΔmsbB ΔrbsA triple mutant at 50 LD50 were 90% protected upon subsequent challenge with 12 LD50 of WT CO92, suggesting that this mutant or others carrying combinational deletions of genes identified through our screen could potentially be further tested and developed into a live attenuated plague vaccine(s). Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Model of pediatric pituitary hormone deficiency separates the endocrine and neural functions of the LHX3 transcription factor in vivo

PubMed Central

Colvin, Stephanie C.; Malik, Raleigh E.; Showalter, Aaron D.; Sloop, Kyle W.; Rhodes, Simon J.

2011-01-01

The etiology of most pediatric hormone deficiency diseases is poorly understood. Children with combined pituitary hormone deficiency (CPHD) have insufficient levels of multiple anterior pituitary hormones causing short stature, metabolic disease, pubertal failure, and often have associated nervous system symptoms. Mutations in developmental regulatory genes required for the specification of the hormone-secreting cell types of the pituitary gland underlie severe forms of CPHD. To better understand these diseases, we have created a unique mouse model of CPHD with a targeted knockin mutation (Lhx3 W227ter), which is a model for the human LHX3 W224ter disease. The LHX3 gene encodes a LIM-homeodomain transcription factor, which has essential roles in pituitary and nervous system development in mammals. The introduced premature termination codon results in deletion of the carboxyl terminal region of the LHX3 protein, which is critical for pituitary gene activation. Mice that lack all LHX3 function do not survive beyond birth. By contrast, the homozygous Lhx3 W227ter mice survive, but display marked dwarfism, thyroid disease, and female infertility. Importantly, the Lhx3 W227ter mice have no apparent nervous system deficits. The Lhx3 W227ter mouse model provides a unique array of hormone deficits and facilitates experimental approaches that are not feasible with human patients. These experiments demonstrate that the carboxyl terminus of the LHX3 transcription factor is not required for viability. More broadly, this study reveals that the in vivo actions of a transcription factor in different tissues are molecularly separable. PMID:21149718

SIRT1 deacetylase protects against neurodegeneration in models for Alzheimer's disease and amyotrophic lateral sclerosis.

PubMed

Kim, Dohoon; Nguyen, Minh Dang; Dobbin, Matthew M; Fischer, Andre; Sananbenesi, Farahnaz; Rodgers, Joseph T; Delalle, Ivana; Baur, Joseph A; Sui, Guangchao; Armour, Sean M; Puigserver, Pere; Sinclair, David A; Tsai, Li-Huei

2007-07-11

A progressive loss of neurons with age underlies a variety of debilitating neurological disorders, including Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), yet few effective treatments are currently available. The SIR2 gene promotes longevity in a variety of organisms and may underlie the health benefits of caloric restriction, a diet that delays aging and neurodegeneration in mammals. Here, we report that a human homologue of SIR2, SIRT1, is upregulated in mouse models for AD, ALS and in primary neurons challenged with neurotoxic insults. In cell-based models for AD/tauopathies and ALS, SIRT1 and resveratrol, a SIRT1-activating molecule, both promote neuronal survival. In the inducible p25 transgenic mouse, a model of AD and tauopathies, resveratrol reduced neurodegeneration in the hippocampus, prevented learning impairment, and decreased the acetylation of the known SIRT1 substrates PGC-1alpha and p53. Furthermore, injection of SIRT1 lentivirus in the hippocampus of p25 transgenic mice conferred significant protection against neurodegeneration. Thus, SIRT1 constitutes a unique molecular link between aging and human neurodegenerative disorders and provides a promising avenue for therapeutic intervention.

SIRT1 deacetylase protects against neurodegeneration in models for Alzheimer's disease and amyotrophic lateral sclerosis

PubMed Central

Kim, Dohoon; Nguyen, Minh Dang; Dobbin, Matthew M; Fischer, Andre; Sananbenesi, Farahnaz; Rodgers, Joseph T; Delalle, Ivana; Baur, Joseph A; Sui, Guangchao; Armour, Sean M; Puigserver, Pere; Sinclair, David A; Tsai, Li-Huei

2007-01-01

A progressive loss of neurons with age underlies a variety of debilitating neurological disorders, including Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), yet few effective treatments are currently available. The SIR2 gene promotes longevity in a variety of organisms and may underlie the health benefits of caloric restriction, a diet that delays aging and neurodegeneration in mammals. Here, we report that a human homologue of SIR2, SIRT1, is upregulated in mouse models for AD, ALS and in primary neurons challenged with neurotoxic insults. In cell-based models for AD/tauopathies and ALS, SIRT1 and resveratrol, a SIRT1-activating molecule, both promote neuronal survival. In the inducible p25 transgenic mouse, a model of AD and tauopathies, resveratrol reduced neurodegeneration in the hippocampus, prevented learning impairment, and decreased the acetylation of the known SIRT1 substrates PGC-1alpha and p53. Furthermore, injection of SIRT1 lentivirus in the hippocampus of p25 transgenic mice conferred significant protection against neurodegeneration. Thus, SIRT1 constitutes a unique molecular link between aging and human neurodegenerative disorders and provides a promising avenue for therapeutic intervention. PMID:17581637

A novel behavioral paradigm for assessing concept of nests in mice

PubMed Central

Kuang, Hui; Mei, Bing; Cui, Zhenzhong; Lin, Longnian; Tsien, Joe Z.

2013-01-01

Abstract concepts in the brain enable humans to efficiently and correctly recognize and categorize a seemingly infinite amount of objects and daily events. Such abstract generalization abilities are traditionally considered to be unique to humans and perhaps non-human primates. However, emerging neurophysiological recordings indicate the existence of neural correlates for the abstract concept of nests in the mouse brain. To facilitate the molecular and genetic analyses of concepts in the mouse model, we have developed a nest generalization test based on mice’s natural behavior. We show that inducible and forebrain-specific NMDA receptor knockout results in pronounced impairment in this test. Interestingly, this generalization deficit could be gradually compensated for over time by repeated experiences even in face of the continued deficit in object recognition memory. On the contrast, the forebrain-specific presenilin-1 knockout mice, which have subtle phenotypes, were normal in performing this test. Therefore, our study not only establishes a quantitative method for assessing the nest concept in mice, but also demonstrates its great potential in combining powerful mouse genetics for dissecting the molecular basis of concept formation in the brain. PMID:20350568

Wnt-Responsive Cancer Stem Cells Are Located Close to Distorted Blood Vessels and Not in Hypoxic Regions in a p53-Null Mouse Model of Human Breast Cancer

PubMed Central

Landua, John D.; Bu, Wen; Wei, Wei; Li, Fuhai; Wong, Stephen T.C.; Dickinson, Mary E.; Rosen, Jeffrey M.; Lewis, Michael T.

2014-01-01

Cancer stem cells (CSCs, or tumor-initiating cells) may be responsible for tumor formation in many types of cancer, including breast cancer. Using high-resolution imaging techniques, we analyzed the relationship between a Wnt-responsive, CSC-enriched population and the tumor vasculature using p53-null mouse mammary tumors transduced with a lentiviral Wnt signaling reporter. Consistent with their localization in the normal mammary gland, Wnt-responsive cells in tumors were enriched in the basal/myoepithelial population and generally located in close proximity to blood vessels. The Wnt-responsive CSCs did not colocalize with the hypoxia-inducible factor 1α-positive cells in these p53-null basal-like tumors. Average vessel diameter and vessel tortuosity were increased in p53-null mouse tumors, as well as in a human tumor xenograft as compared with the normal mammary gland. The combined strategy of monitoring the fluorescently labeled CSCs and vasculature using high-resolution imaging techniques provides a unique opportunity to study the CSC and its surrounding vasculature. PMID:24797826

Establishment of a Mouse Model with Misregulated Chromosome Condensation due to Defective Mcph1 Function

PubMed Central

Walther, Diego J.; Dopatka, Monika; Dutrannoy, Véronique; Busche, Andreas; Meyer, Franziska; Nowak, Stefanie; Nowak, Jean; Zabel, Claus; Klose, Joachim; Esquitino, Veronica; Garshasbi, Masoud; Kuss, Andreas W.; Ropers, Hans-Hilger; Mueller, Susanne; Poehlmann, Charlotte; Gavvovidis, Ioannis; Schindler, Detlev; Sperling, Karl; Neitzel, Heidemarie

2010-01-01

Mutations in the human gene MCPH1 cause primary microcephaly associated with a unique cellular phenotype with premature chromosome condensation (PCC) in early G2 phase and delayed decondensation post-mitosis (PCC syndrome). The gene encodes the BRCT-domain containing protein microcephalin/BRIT1. Apart from its role in the regulation of chromosome condensation, the protein is involved in the cellular response to DNA damage. We report here on the first mouse model of impaired Mcph1-function. The model was established based on an embryonic stem cell line from BayGenomics (RR0608) containing a gene trap in intron 12 of the Mcph1 gene deleting the C-terminal BRCT-domain of the protein. Although residual wild type allele can be detected by quantitative real-time PCR cell cultures generated from mouse tissues bearing the homozygous gene trap mutation display the cellular phenotype of misregulated chromosome condensation that is characteristic for the human disorder, confirming defective Mcph1 function due to the gene trap mutation. While surprisingly the DNA damage response (formation of repair foci, chromosomal breakage, and G2/M checkpoint function after irradiation) appears to be largely normal in cell cultures derived from Mcph1gt/gt mice, the overall survival rates of the Mcph1gt/gt animals are significantly reduced compared to wild type and heterozygous mice. However, we could not detect clear signs of premature malignant disease development due to the perturbed Mcph1 function. Moreover, the animals show no obvious physical phenotype and no reduced fertility. Body and brain size are within the range of wild type controls. Gene expression on RNA and protein level did not reveal any specific pattern of differentially regulated genes. To the best of our knowledge this represents the first mammalian transgenic model displaying a defect in mitotic chromosome condensation and is also the first mouse model for impaired Mcph1-function. PMID:20169082

Establishment of a mouse model with misregulated chromosome condensation due to defective Mcph1 function.

PubMed

Trimborn, Marc; Ghani, Mahdi; Walther, Diego J; Dopatka, Monika; Dutrannoy, Véronique; Busche, Andreas; Meyer, Franziska; Nowak, Stefanie; Nowak, Jean; Zabel, Claus; Klose, Joachim; Esquitino, Veronica; Garshasbi, Masoud; Kuss, Andreas W; Ropers, Hans-Hilger; Mueller, Susanne; Poehlmann, Charlotte; Gavvovidis, Ioannis; Schindler, Detlev; Sperling, Karl; Neitzel, Heidemarie

2010-02-16

Mutations in the human gene MCPH1 cause primary microcephaly associated with a unique cellular phenotype with premature chromosome condensation (PCC) in early G2 phase and delayed decondensation post-mitosis (PCC syndrome). The gene encodes the BRCT-domain containing protein microcephalin/BRIT1. Apart from its role in the regulation of chromosome condensation, the protein is involved in the cellular response to DNA damage. We report here on the first mouse model of impaired Mcph1-function. The model was established based on an embryonic stem cell line from BayGenomics (RR0608) containing a gene trap in intron 12 of the Mcph1 gene deleting the C-terminal BRCT-domain of the protein. Although residual wild type allele can be detected by quantitative real-time PCR cell cultures generated from mouse tissues bearing the homozygous gene trap mutation display the cellular phenotype of misregulated chromosome condensation that is characteristic for the human disorder, confirming defective Mcph1 function due to the gene trap mutation. While surprisingly the DNA damage response (formation of repair foci, chromosomal breakage, and G2/M checkpoint function after irradiation) appears to be largely normal in cell cultures derived from Mcph1(gt/gt) mice, the overall survival rates of the Mcph1(gt/gt) animals are significantly reduced compared to wild type and heterozygous mice. However, we could not detect clear signs of premature malignant disease development due to the perturbed Mcph1 function. Moreover, the animals show no obvious physical phenotype and no reduced fertility. Body and brain size are within the range of wild type controls. Gene expression on RNA and protein level did not reveal any specific pattern of differentially regulated genes. To the best of our knowledge this represents the first mammalian transgenic model displaying a defect in mitotic chromosome condensation and is also the first mouse model for impaired Mcph1-function.

Use of “MGE Enhancers” for Labeling and Selection of Embryonic Stem Cell-Derived Medial Ganglionic Eminence (MGE) Progenitors and Neurons

PubMed Central

Chen, Ying-Jiun J.; Vogt, Daniel; Wang, Yanling; Visel, Axel; Silberberg, Shanni N.; Nicholas, Cory R.; Danjo, Teruko; Pollack, Joshua L.; Pennacchio, Len A.; Anderson, Stewart; Sasai, Yoshiki; Baraban, Scott C.; Kriegstein, Arnold R.; Alvarez-Buylla, Arturo; Rubenstein, John L. R.

2013-01-01

The medial ganglionic eminence (MGE) is an embryonic forebrain structure that generates the majority of cortical interneurons. MGE transplantation into specific regions of the postnatal central nervous system modifies circuit function and improves deficits in mouse models of epilepsy, Parkinson's disease, pain, and phencyclidine-induced cognitive deficits. Herein, we describe approaches to generate MGE-like progenitor cells from mouse embryonic stem (ES) cells. Using a modified embryoid body method, we provided gene expression evidence that mouse ES-derived Lhx6+ cells closely resemble immature interneurons generated from authentic MGE-derived Lhx6+ cells. We hypothesized that enhancers that are active in the mouse MGE would be useful tools in detecting when ES cells differentiate into MGE cells. Here we demonstrate the utility of enhancer elements [422 (DlxI12b), Lhx6, 692, 1056, and 1538] as tools to mark MGE-like cells in ES cell differentiation experiments. We found that enhancers DlxI12b, 692, and 1538 are active in Lhx6-GFP+ cells, while enhancer 1056 is active in Olig2+ cells. These data demonstrate unique techniques to follow and purify MGE-like derivatives from ES cells, including GABAergic cortical interneurons and oligodendrocytes, for use in stem cell-based therapeutic assays and treatments. PMID:23658702

A comprehensive proteomics and genomics analysis reveals novel transmembrane proteins in human platelets and mouse megakaryocytes including G6b-B, a novel ITIM protein

PubMed Central

Senis, Yotis A.; Tomlinson, Michael G.; García, Ángel; Dumon, Stephanie; Heath, Victoria L.; Herbert, John; Cobbold, Stephen P.; Spalton, Jennifer C.; Ayman, Sinem; Antrobus, Robin; Zitzmann, Nicole; Bicknell, Roy; Frampton, Jon; Authi, Kalwant; Martin, Ashley; Wakelam, Michael J.O.; Watson, Stephen P.

2007-01-01

Summary The platelet surface is poorly characterized due to the low abundance of many membrane proteins and the lack of specialist tools for their investigation. In this study we have identified novel human platelet and mouse megakaryocyte membrane proteins using specialist proteomic and genomic approaches. Three separate methods were used to enrich platelet surface proteins prior to identification by liquid chromatography and tandem mass spectrometry: lectin affinity chromatography; biotin/NeutrAvidin affinity chromatography; and free flow electrophoresis. Many known, abundant platelet surface transmembrane proteins and several novel proteins were identified using each receptor enrichment strategy. In total, two or more unique peptides were identified for 46, 68 and 22 surface membrane, intracellular membrane and membrane proteins of unknown sub-cellular localization, respectively. The majority of these were single transmembrane proteins. To complement the proteomic studies, we analysed the transcriptome of a highly purified preparation of mature primary mouse megakaryocytes using serial analysis of gene expression in view of the increasing importance of mutant mouse models in establishing protein function in platelets. This approach identified all of the major classes of platelet transmembrane receptors, including multi-transmembrane proteins. Strikingly, 17 of the 25 most megakaryocyte-specific genes (relative to 30 other SAGE libraries) were transmembrane proteins, illustrating the unique nature of the megakaryocyte/platelet surface. The list of novel plasma membrane proteins identified using proteomics includes the immunoglobulin superfamily member G6b, which undergoes extensive alternate splicing. Specific antibodies were used to demonstrate expression of the G6b-B isoform, which contains an immunoreceptor tyrosine-based inhibition motif. G6b-B undergoes tyrosine phosphorylation and association with the SH2-containing phosphatase, SHP-1, in stimulated platelets suggesting that it may play a novel role in limiting platelet activation. PMID:17186946

Marek's disease is a natural model for lymphomas overexpressing Hodgkin's disease antigen (CD30)

PubMed Central

Burgess, S. C.; Young, J. R.; Baaten, B. J. G.; Hunt, L.; Ross, L. N. J.; Parcells, M. S.; Kumar, P. M.; Tregaskes, C. A.; Lee, L. F.; Davison, T. F.

2004-01-01

Animal models are essential for elucidating the molecular mechanisms of carcinogenesis. Hodgkin's and many diverse non-Hodgkin's lymphomas overexpress the Hodgkin's disease antigen CD30 (CD30hi), a tumor necrosis factor receptor II family member. Here we show that chicken Marek's disease (MD) lymphoma cells are also CD30hi and are a unique natural model for CD30hi lymphoma. Chicken CD30 resembles an ancestral form, and we identify a previously undescribed potential cytoplasmic signaling domain conserved in chicken, human, and mouse CD30. Our phylogeneic analysis defines a relationship between the structures of human and mouse CD30 and confirms that mouse CD30 represents the ancestral mammalian gene structure. CD30 expression by MD virus (MDV)-transformed lymphocytes correlates with expression of the MDV Meq putative oncogene (a c-Jun homologue) in vivo. The chicken CD30 promoter has 15 predicted high-stringency Meq-binding transcription factor recognition motifs, and Meq enhances transcription from the CD30 promoter in vitro. Plasma proteomics identified a soluble form of CD30. CD30 overexpression is evolutionarily conserved and defines one class of neoplastic transformation events, regardless of etiology. We propose that CD30 is a component of a critical intracellular signaling pathway perturbed in neoplastic transformation. Specific anti-CD30 Igs occurred after infection of genetically MD-resistant chickens with oncogenic MDV, suggesting immunity to CD30 could play a role in MD lymphoma regression. PMID:15356338

The promise of copper lowering therapy with tetrathiomolybdate in the cure of cancer and in the treatment of inflammatory disease.

PubMed

Brewer, George J

2014-10-01

Tetrathiomolybdate (TM) is a unique anticopper drug developed for the treatment of the neurologic presentation of Wilson's disease, for which it is excellent. Since it was known copper was required for angiogenesis, TM was tested on mouse cancer models to see if it would inhibit tumor growth based on an antiangiogenic effect. TM was extremely effective in these models, but all the tumors in the models started small in size - micrometastatic in size. Later, TM was tested in numerous human cancer trials, where it showed only modest effects. However, the mouse lesson of efficacy against micro disease was forgotten - all the trials were against bulky, advanced cancer. Now, the mouse evidence is coming back to life. Three groups are curing, or having major efficacy of TM, against advanced human cancers, heretofore virtually incurable, particularly if the cancer has been reduced to no evidence of disease (NED) status by conventional therapy. In that situation, where the remaining disease is micrometastatic, TM therapy appears to be curative. We have designed and initiated a study of TM in canine osteosarcoma at the micrometastatic phase to help put these findings on a firm scientific basis. TM also has major anti-inflammatory properties by inhibiting copper dependent cytokines involved in inflammation. This anti-inflammatory effect may be involved in TM's anticancer effect because cancers, as they advance, attract inflammatory cells that provide a plethora of additional proangiogenic agents. Copyright © 2014 Elsevier GmbH. All rights reserved.

Several Classical Mouse Inbred Strains, Including DBA/2, NOD/Lt, FVB/N, and SJL/J, Carry a Putative Loss-of-Function Allele of Gpr84

PubMed Central

2013-01-01

G protein–coupled receptor 84 (GPR84) is a 7-transmembrane protein expressed on myeloid cells that can bind to medium-chain free fatty acids in vitro. Here, we report the discovery of a 2-bp frameshift deletion in the second exon of the Gpr84 gene in several classical mouse inbred strains. This deletion generates a premature stop codon predicted to result in a truncated protein lacking the transmembrane domains 4-7. We sequenced Gpr84 exon 2 from 58 strains representing different groups in the mouse family tree and found that 14 strains are homozygous for the deletion. Some of these strains are DBA/1J, DBA/2J, FVB/NJ, LG/J, MRL/MpJ, NOD/LtJ, and SJL/J. However, the deletion was not found in any of the wild-derived inbred strains analyzed. Haplotype analysis suggested that the deletion originates from a unique mutation event that occurred more than 100 years ago, preceding the development of the first inbred strain (DBA), from a Mus musculus domesticus source. As GPR84 ostensibly plays a role in the biology of myeloid cells, it could be relevant 1) to consider the existence of this Gpr84 nonsense mutation in several mouse strains when choosing a mouse model to study immune processes and 2) to consider reevaluating data obtained using such strains. PMID:23616478

Several classical mouse inbred strains, including DBA/2, NOD/Lt, FVB/N, and SJL/J, carry a putative loss-of-function allele of Gpr84.

PubMed

Perez, Carlos J; Dumas, Aline; Vallières, Luc; Guénet, Jean-Louis; Benavides, Fernando

2013-01-01

G protein-coupled receptor 84 (GPR84) is a 7-transmembrane protein expressed on myeloid cells that can bind to medium-chain free fatty acids in vitro. Here, we report the discovery of a 2-bp frameshift deletion in the second exon of the Gpr84 gene in several classical mouse inbred strains. This deletion generates a premature stop codon predicted to result in a truncated protein lacking the transmembrane domains 4-7. We sequenced Gpr84 exon 2 from 58 strains representing different groups in the mouse family tree and found that 14 strains are homozygous for the deletion. Some of these strains are DBA/1J, DBA/2J, FVB/NJ, LG/J, MRL/MpJ, NOD/LtJ, and SJL/J. However, the deletion was not found in any of the wild-derived inbred strains analyzed. Haplotype analysis suggested that the deletion originates from a unique mutation event that occurred more than 100 years ago, preceding the development of the first inbred strain (DBA), from a Mus musculus domesticus source. As GPR84 ostensibly plays a role in the biology of myeloid cells, it could be relevant 1) to consider the existence of this Gpr84 nonsense mutation in several mouse strains when choosing a mouse model to study immune processes and 2) to consider reevaluating data obtained using such strains.

Ex vivo optical coherence tomography and laser induced fluorescence spectroscopy imaging of murine gastrointestinal tract

NASA Astrophysics Data System (ADS)

Hariri, Lida; Tumlinson, Alexandre R.; Wade, Norman; Besselsen, David; Utzinger, Urs; Gerner, Eugene; Barton, Jennifer

2005-04-01

Optical Coherence Tomography (OCT) and Laser Induced Fluorescence Spectroscopy (LIF) have separately been found to have clinical potential in identifying human gastrointestinal (GI) pathologies, yet their diagnostic capability in mouse models of human disease is unknown. We combine the two modalities to survey the GI tract of a variety of mouse strains and sample dysplasias and inflammatory bowel disease (IBD) of the small and large intestine. Segments of duodenum and lower colon 2.5 cm in length and the entire esophagus from 10 mice each of two colon cancer models (ApcMin and AOM treated A/J) and two IBD models (Il-2 and Il-10) and 5 mice each of their respective controls were excised. OCT images and LIF spectra were obtained simultaneously from each tissue sample within 1 hour of extraction. Histology was used to classify tissue regions as normal, Peyer"s patch, dysplasia, adenoma, or IBD. Features in corresponding regions of OCT images were analyzed. Spectra from each of these categories were averaged and compared via the student's t-test. Features in OCT images correlated to histology in both normal and diseased tissue samples. In the diseased samples, OCT was able to identify early stages of mild colitis and dysplasia. In the sample of IBD, the LIF spectra displayed unique peaks at 635nm and 670nm, which were attributed to increased porphyrin production in the proliferating bacteria of the disease. These peaks have the potential to act as a diagnostic for IBD. OCT and LIF appear to be useful and complementary modalities for imaging mouse models.

Ultraperformance convergence chromatography-high resolution tandem mass spectrometry for lipid biomarker profiling and identification.

PubMed

Jones, Jace W; Carter, Claire L; Li, Fei; Yu, Jianshi; Pierzchalski, Keely; Jackson, Isabel L; Vujaskovic, Zeljko; Kane, Maureen A

2017-03-01

Lipids represent biologically ubiquitous and highly dynamic molecules in terms of abundance and structural diversity. Whereas the potential for lipids to inform on disease/injury is promising, their unique characteristics make detection and identification of lipids from biological samples analytically demanding. We report the use of ultraperformance convergence chromatography (UPC 2 ), a variant of supercritical fluid chromatography, coupled to high-resolution, data-independent tandem mass spectrometry for characterization of total lipid extracts from mouse lung tissue. The UPC 2 platform resulted in lipid class separation and when combined with orthogonal column chemistries yielded chromatographic separation of intra-class species based on acyl chain hydrophobicity. Moreover, the combined approach of using UPC 2 with orthogonal column chemistries, accurate mass measurements, time-aligned low- and high-collision energy total ion chromatograms, and positive and negative ion mode product ion spectra correlation allowed for confident lipid identification. Of great interest was the identification of differentially expressed ceramides that were elevated 24 h post whole thorax lung irradiation. The identification of lipids that were elevated 24 h post-irradiation signifies a unique opportunity to investigate early mechanisms of action prior to the onset of clinical symptoms in the whole thorax lung irradiation mouse model. Copyright © 2016 John Wiley & Sons, Ltd.

Liver-derived systemic factors drive β-cell hyperplasia in insulin resistant states

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

El Ouaamari, Abdelfattah; Kawamori, Dan; Dirice, Ercument

2013-02-21

Integrative organ cross-talk regulates key aspects of energy homeostasis and its dysregulation may underlie metabolic disorders such as obesity and diabetes. To test the hypothesis that cross-talk between the liver and pancreatic islets modulates β-cell growth in response to insulin resistance, we used the Liver-specific Insulin Receptor Knockout (LIRKO) mouse, a unique model that exhibits dramatic islet hyperplasia. Using complementary in vivo parabiosis and transplantation assays, and in vitro islet culture approaches, we demonstrate that humoral, non-neural, non-cell autonomous factor(s) induce β-cell proliferation in LIRKO mice. Furthermore, we report that a hepatocyte-derived factor(s) stimulates mouse and human β-cell proliferation inmore » ex vivo assays, independent of ambient glucose and insulin levels. These data implicate the liver as a critical source of β-cell growth factors in insulin resistant states.« less

Recurrence of 49-base decamers, nonomers, and octamers within mouse C mu gene of Ig heavy chain and its primordial building block.

PubMed Central

Yazaki, A; Ohno, S

1983-01-01

Within the published 2,168-base-long mouse C mu gene of Ig heavy chain consisting of four coding and four noncoding segments, 2 base decamers, 8 nonomers, and 39 octamers recurred. Recurring base heptamers (about 100) and hexamers (about 350) were simply too numerous to merit individual identification. In spite of extensive overlaps between these recurring base decamers to hexamers, they occupied nearly the entire length of mouse Ig C mu gene. As with other genes of the beta-sheet-forming beta 2-microglobulin family, the Ig C mu gene (flanking and intervening noncoding sequences included) is not a unique sequence but rather it is degenerate repeats of the 45-base-long primordial building-block sequence uniquely its own. This primordial building block must originally have specified the 15-amino-acid-residue-long primordial arm of beta-sheet-forming loops, the characteristics of the beta 2-microglobulin family of polypeptides. PMID:6403948

Manipulation of the mouse genome: a multiple impact resource for drug discovery and development.

PubMed

Prosser, Haydn; Rastan, Sohaila

2003-05-01

Few would deny that the pharmaceutical industry's investment in genomics throughout the 1990s has yet to deliver in terms of drugs on the market. The reasons are complex and beyond the scope of this review. The unique ability to manipulate the mouse genome, however, has already had a positive impact on all stages of the drug discovery process and, increasingly, on the drug development process too. We give an overview of some recent applications of so-called 'transgenic' mouse technology in pharmaceutical research and development. We show how genetic manipulation in the mouse can be employed at multiple points in the drug discovery and development process, providing new solutions to old problems.

Multiple autism-like behaviors in a novel transgenic mouse model

PubMed Central

Hamilton, Shannon M.; Spencer, Corinne M.; Harrison, Wilbur R.; Yuva-Paylor, Lisa A.; Graham, Deanna F.; Daza, Ray A.M.; Hevner, Robert F.; Overbeek, Paul A.; Paylor, Richard

2011-01-01

Autism spectrum disorder (ASD) diagnoses are behaviorally-based with no defined universal biomarkers, occur at a 1:110 ratio in the population, and predominantly affect males compared to females at approximately a 4:1 ratio. One approach to investigate and identify causes of ASD is to use organisms that display abnormal behavioral responses that model ASD-related impairments. This study describes a novel transgenic mouse, MALTT, which was generated using a forward genetics approach. It was determined that the transgene integrated within a noncoding region on the X chromosome. The MALTT line exhibited a complete repertoire of ASD-like behavioral deficits in all three domains required for an ASD diagnosis: reciprocal social interaction, communication, and repetitive or inflexible behaviors. Specifically, MALTT male mice showed deficits in social interaction and interest, abnormalities in pup and juvenile ultrasonic vocalization communications, and exhibited a repetitive stereotypy. Abnormalities were also observed in the domain of sensory function, a secondary phenotype prevalently associated with ASD. Mapping and expression studies suggested that the Fam46 gene family may be linked to the observed ASD-related behaviors. The MALTT line provides a unique genetic model for examining the underlying biological mechanisms involved in ASD-related behaviors. PMID:21093492

Mitochondrial dysfunction, oxidative stress and apoptosis revealed by proteomic and transcriptomic analyses of the striata in two mouse models of Parkinson’s disease

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

Chin, Mark H.; Qian, Weijun; Wang, Haixing

2008-02-10

The molecular mechanisms underlying the changes in the nigrostriatal pathway in Parkinson disease (PD) are not completely understood. Here we use mass spectrometry and microarrays to study the proteomic and transcriptomic changes in the striatum of two mouse models of PD, induced by the distinct neurotoxins 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and methamphetamine (METH). Proteomic analyses resulted in the identification and relative quantification of 912 proteins with two or more unique peptides and 85 proteins with significant abundance changes following neurotoxin treatment. Similarly, microarray analyses revealed 181 genes with significant changes in mRNA following neurotoxin treatment. The combined protein and gene list providesmore » a clearer picture of the potential mechanisms underlying neurodegeneration observed in PD. Functional analysis of this combined list revealed a number of significant categories, including mitochondrial dysfunction, oxidative stress response and apoptosis. Additionally, codon usage and miRNAs may play an important role in translational control in the striatum. These results constitute one of the largest datasets integrating protein and transcript changes for these neurotoxin models with many similar endpoint phenotypes but distinct mechanisms.« less

AHCODA-DB: a data repository with web-based mining tools for the analysis of automated high-content mouse phenomics data.

PubMed

Koopmans, Bastijn; Smit, August B; Verhage, Matthijs; Loos, Maarten

2017-04-04

Systematic, standardized and in-depth phenotyping and data analyses of rodent behaviour empowers gene-function studies, drug testing and therapy design. However, no data repositories are currently available for standardized quality control, data analysis and mining at the resolution of individual mice. Here, we present AHCODA-DB, a public data repository with standardized quality control and exclusion criteria aimed to enhance robustness of data, enabled with web-based mining tools for the analysis of individually and group-wise collected mouse phenotypic data. AHCODA-DB allows monitoring in vivo effects of compounds collected from conventional behavioural tests and from automated home-cage experiments assessing spontaneous behaviour, anxiety and cognition without human interference. AHCODA-DB includes such data from mutant mice (transgenics, knock-out, knock-in), (recombinant) inbred strains, and compound effects in wildtype mice and disease models. AHCODA-DB provides real time statistical analyses with single mouse resolution and versatile suite of data presentation tools. On March 9th, 2017 AHCODA-DB contained 650 k data points on 2419 parameters from 1563 mice. AHCODA-DB provides users with tools to systematically explore mouse behavioural data, both with positive and negative outcome, published and unpublished, across time and experiments with single mouse resolution. The standardized (automated) experimental settings and the large current dataset (1563 mice) in AHCODA-DB provide a unique framework for the interpretation of behavioural data and drug effects. The use of common ontologies allows data export to other databases such as the Mouse Phenome Database. Unbiased presentation of positive and negative data obtained under the highly standardized screening conditions increase cost efficiency of publicly funded mouse screening projects and help to reach consensus conclusions on drug responses and mouse behavioural phenotypes. The website is publicly accessible through https://public.sylics.com and can be viewed in every recent version of all commonly used browsers.

The pleiotropic transcriptional regulator COUP-TFI plays multiple roles in neural development and disease.

PubMed

Bertacchi, Michele; Parisot, Josephine; Studer, Michèle

2018-04-27

Transcription factors are expressed in a dynamic fashion both in time and space during brain development, and exert their roles by activating a cascade of multiple target genes. This implies that understanding the precise function of a transcription factor becomes a challenging task. In this review, we will focus on COUP-TFI (or NR2F1), a nuclear receptor belonging to the superfamily of the steroid/thyroid hormone receptors, and considered to be one of the major transcriptional regulators orchestrating cortical arealization, cell-type specification and maturation. Recent data have unraveled the multi-faceted functions of COUP-TFI in the development of several mouse brain structures, including the neocortex, hippocampus and ganglionic eminences. Despite NR2F1 mutations and deletions in humans have been linked to a complex neurodevelopmental disease mainly associated to optic atrophy and intellectual disability, its role during the formation of the retina and optic nerve remains unclear. In light of its major influence in cortical development, we predict that its haploinsufficiency might be the cause of other cognitive diseases, not identified so far. Mouse models offer a unique opportunity of dissecting COUP-TFI function in different regions during brain assembly; hence, the importance of comparing and discussing common points linking mouse models to human patients' symptoms. Copyright © 2018 Elsevier B.V. All rights reserved.

Mapping arealisation of the visual cortex of non-primate species: lessons for development and evolution

PubMed Central

Homman-Ludiye, Jihane; Bourne, James A.

2014-01-01

The integration of the visual stimulus takes place at the level of the neocortex, organized in anatomically distinct and functionally unique areas. Primates, including humans, are heavily dependent on vision, with approximately 50% of their neocortical surface dedicated to visual processing and possess many more visual areas than any other mammal, making them the model of choice to study visual cortical arealisation. However, in order to identify the mechanisms responsible for patterning the developing neocortex, specifying area identity as well as elucidate events that have enabled the evolution of the complex primate visual cortex, it is essential to gain access to the cortical maps of alternative species. To this end, species including the mouse have driven the identification of cellular markers, which possess an area-specific expression profile, the development of new tools to label connections and technological advance in imaging techniques enabling monitoring of cortical activity in a behaving animal. In this review we present non-primate species that have contributed to elucidating the evolution and development of the visual cortex. We describe the current understanding of the mechanisms supporting the establishment of areal borders during development, mainly gained in the mouse thanks to the availability of genetically modified lines but also the limitations of the mouse model and the need for alternate species. PMID:25071460

Motor and cognitive stereotypies in the BTBR T+tf/J mouse model of autism.

PubMed

Pearson, B L; Pobbe, R L H; Defensor, E B; Oasay, L; Bolivar, V J; Blanchard, D C; Blanchard, R J

2011-03-01

The BTBR T+tf/J inbred mouse strain displays a variety of persistent phenotypic alterations similar to those exhibited in autism spectrum disorders (ASDs). The unique genetic background of the BTBR strain is thought to underlie its lack of reciprocal social interactions, elevated repetitive self-directed grooming, and restricted exploratory behaviors. In order to clarify the existence, range, and mechanisms of abnormal repetitive behaviors within BTBR mice, we performed detailed analyses of the microstructure of self-grooming patterns and noted increased overall grooming, higher percentages of interruptions in grooming bouts and a concomitant decrease in the proportion of incorrect sequence transitions compared to C57BL/6J inbred mice. Analyses of active phase home-cage behavior also revealed an increase in stereotypic bar-biting behavior in the BTBR strain relative to B6 mice. Finally, in a novel object investigation task, the BTBR mice exhibited greater baseline preference for specific unfamiliar objects as well as more patterned sequences of sequential investigations of those items. These results suggest that the repetitive, stereotyped behavior patterns of BTBR mice are relatively pervasive and reflect both motor and cognitive mechanisms. Furthermore, other pre-clinical mouse models of ASDs may benefit from these more detailed analyses of stereotypic behavior. © 2010 The Authors. Genes, Brain and Behavior © 2010 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

A novel Phex mutation with defective glycosylation causes hypophosphatemia and rickets in mice.

PubMed

Xiong, Xiwen; Qi, Xin; Ge, Xiaomei; Gu, Pengyu; Zhao, Jing; Zhao, Qingshun; Gao, Xiang

2008-01-01

N-ethyl-N-nitrosourea (ENU) mutagenesis is a phenotype-driven approach with potential to assign function to every locus in the mouse genome. In this article, we describe a new mutation, Pug, as a mouse model for X-linked hypophosphatemic rickets (XLH) in human. Mice carrying the Pug mutation exhibit abnormal phenotypes including growth retardation, hypophosphatemia and decreased bone mineral density (BMD). The new mutation was mapped to X-chromosome between 65.4 cM and 66.6 cM, where Phex gene resides. Sequence analysis revealed a unique T-to-C transition mutation resulting in Phe-to-Ser substitution at amino acid 80 of PHEX protein. In vitro studies of Pug mutation demonstrated that PHEX(pug) was incompletely glycosylated and sequestrated in the endoplasmic reticulum region of cell, whereas wild-type PHEX could be fully glycosylated and transported to the plasma membrane to exert its function as an endopeptidase. Taken together, the Pug mutant directly confirms the role of Phex in phosphate homeostasis and normal skeletal development and may serves as a new disease model of human hypophosphatemic rickets.

Modeling and image reconstruction in spectrally resolved bioluminescence tomography

NASA Astrophysics Data System (ADS)

Dehghani, Hamid; Pogue, Brian W.; Davis, Scott C.; Patterson, Michael S.

2007-02-01

Recent interest in modeling and reconstruction algorithms for Bioluminescence Tomography (BLT) has increased and led to the general consensus that non-spectrally resolved intensity-based BLT results in a non-unique problem. However, the light emitted from, for example firefly Luciferase, is widely distributed over the band of wavelengths from 500 nm to 650 nm and above, with the dominant fraction emitted from tissue being above 550 nm. This paper demonstrates the development of an algorithm used for multi-wavelength 3D spectrally resolved BLT image reconstruction in a mouse model. It is shown that using a single view data, bioluminescence sources of up to 15 mm deep can be successfully recovered given correct information about the underlying tissue absorption and scatter.

The Bat as a New Model of Cortical Development.

PubMed

Martínez-Cerdeño, Verónica; Camacho, Jasmin; Ariza, Jeanelle; Rogers, Hailee; Horton-Sparks, Kayla; Kreutz, Anna; Behringer, Richard; Rasweiler, John J; Noctor, Stephen C

2017-11-09

The organization of the mammalian cerebral cortex shares fundamental features across species. However, while the radial thickness of grey matter varies within one order of magnitude, the tangential spread of the cortical sheet varies by orders of magnitude across species. A broader sample of model species may provide additional clues for understanding mechanisms that drive cortical expansion. Here, we introduce the bat Carollia perspicillata as a new model species. The brain of C. perspicillata is similar in size to that of mouse but has a cortical neurogenic period at least 5 times longer than mouse, and nearly as long as that of the rhesus macaque, whose brain is 100 times larger. We describe the development of laminar and regional structures, neural precursor cell identity and distribution, immune cell distribution, and a novel population of Tbr2+ cells in the caudal ganglionic eminence of the developing neocortex of C. perspicillata. Our data indicate that unique mechanisms guide bat cortical development, particularly concerning cell cycle length. The bat model provides new perspective on the evolution of developmental programs that regulate neurogenesis in mammalian cerebral cortex, and offers insight into mechanisms that contribute to tangential expansion and gyri formation in the cerebral cortex. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

A novel mouse model identifies cooperating mutations and therapeutic targets critical for chronic myeloid leukemia progression

PubMed Central

Giotopoulos, George; van der Weyden, Louise; Osaki, Hikari; Rust, Alistair G.; Gallipoli, Paolo; Meduri, Eshwar; Horton, Sarah J.; Chan, Wai-In; Foster, Donna; Prinjha, Rab K.; Pimanda, John E.; Tenen, Daniel G.; Vassiliou, George S.; Koschmieder, Steffen; Adams, David J.

2015-01-01

The introduction of highly selective ABL-tyrosine kinase inhibitors (TKIs) has revolutionized therapy for chronic myeloid leukemia (CML). However, TKIs are only efficacious in the chronic phase of the disease and effective therapies for TKI-refractory CML, or after progression to blast crisis (BC), are lacking. Whereas the chronic phase of CML is dependent on BCR-ABL, additional mutations are required for progression to BC. However, the identity of these mutations and the pathways they affect are poorly understood, hampering our ability to identify therapeutic targets and improve outcomes. Here, we describe a novel mouse model that allows identification of mechanisms of BC progression in an unbiased and tractable manner, using transposon-based insertional mutagenesis on the background of chronic phase CML. Our BC model is the first to faithfully recapitulate the phenotype, cellular and molecular biology of human CML progression. We report a heterogeneous and unique pattern of insertions identifying known and novel candidate genes and demonstrate that these pathways drive disease progression and provide potential targets for novel therapeutic strategies. Our model greatly informs the biology of CML progression and provides a potent resource for the development of candidate therapies to improve the dismal outcomes in this highly aggressive disease. PMID:26304963

Independent Neuronal Origin of Seizures and Behavioral Comorbidities in an Animal Model of a Severe Childhood Genetic Epileptic Encephalopathy

PubMed Central

Asinof, Samuel K.; Sukoff Rizzo, Stacey J.; Buckley, Alexandra R.; Beyer, Barbara J.; Letts, Verity A.; Frankel, Wayne N.; Boumil, Rebecca M.

2015-01-01

The childhood epileptic encephalopathies (EE’s) are seizure disorders that broadly impact development including cognitive, sensory and motor progress with severe consequences and comorbidities. Recently, mutations in DNM1 (dynamin 1) have been implicated in two EE syndromes, Lennox-Gastaut Syndrome and Infantile Spasms. Dnm1 encodes dynamin 1, a large multimeric GTPase necessary for activity-dependent membrane recycling in neurons, including synaptic vesicle endocytosis. Dnm1Ftfl or “fitful” mice carry a spontaneous mutation in the mouse ortholog of DNM1 and recapitulate many of the disease features associated with human DNM1 patients, providing a relevant disease model of human EE’s. In order to examine the cellular etiology of seizures and behavioral and neurological comorbidities, we engineered a conditional Dnm1Ftfl mouse model of DNM1 EE. Observations of Dnm1 Ftfl/flox mice in combination with various neuronal subpopulation specific cre strains demonstrate unique seizure phenotypes and clear separation of major neurobehavioral comorbidities from severe seizures associated with the germline model. This demonstration of pleiotropy suggests that treating seizures per se may not prevent severe comorbidity observed in EE associated with dynamin-1 mutations, and is likely to have implications for other genetic forms of EE. PMID:26125563

Laser Fusion of Mouse Embryonic Cells and Intra-Embryonic Fusion of Blastomeres without Affecting the Embryo Integrity

PubMed Central

Krivokharchenko, Alexander; Karmenyan, Artashes; Sarkisov, Oleg; Bader, Michael; Chiou, Arthur; Shakhbazyan, Avetik

2012-01-01

Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our experiments we have successfully used high repetition rate picosecond near infrared laser beam for fusion of pairs of oocytes and oocytes with blastomeres. Fused cells looked morphologically normal and keep their ability for further divisions in vitro. We also fused two or three blastomeres inside four-cell mouse embryos. The presence of one, two or three nuclei in different blastomeres of the same early preimplantation mouse embryo was confirmed under UV-light after staining of DNA with the vital dye Hoechst-33342. The most of established embryos demonstrated high viability and developed in vitro to the blastocyst stage. We demonstrated for the first time the use of laser beam for the fusion of various embryonic cells of different size and of two or three blastomeres inside of four-cell mouse embryos without affecting the embryo’s integrity and viability. These embryos with blastomeres of various ploidy maybe unique model for numerous purposes. Thus, we propose laser optical manipulation as a new tool for investigation of fundamental mechanisms of mammalian development. PMID:23227157

Laser fusion of mouse embryonic cells and intra-embryonic fusion of blastomeres without affecting the embryo integrity.

PubMed

Krivokharchenko, Alexander; Karmenyan, Artashes; Sarkisov, Oleg; Bader, Michael; Chiou, Arthur; Shakhbazyan, Avetik

2012-01-01

Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our experiments we have successfully used high repetition rate picosecond near infrared laser beam for fusion of pairs of oocytes and oocytes with blastomeres. Fused cells looked morphologically normal and keep their ability for further divisions in vitro. We also fused two or three blastomeres inside four-cell mouse embryos. The presence of one, two or three nuclei in different blastomeres of the same early preimplantation mouse embryo was confirmed under UV-light after staining of DNA with the vital dye Hoechst-33342. The most of established embryos demonstrated high viability and developed in vitro to the blastocyst stage. We demonstrated for the first time the use of laser beam for the fusion of various embryonic cells of different size and of two or three blastomeres inside of four-cell mouse embryos without affecting the embryo's integrity and viability. These embryos with blastomeres of various ploidy maybe unique model for numerous purposes. Thus, we propose laser optical manipulation as a new tool for investigation of fundamental mechanisms of mammalian development.

Epithelial estrogen receptor 1 intrinsically mediates squamous differentiation in the mouse vagina.

PubMed

Miyagawa, Shinichi; Iguchi, Taisen

2015-10-20

Estrogen-mediated actions in female reproductive organs are tightly regulated, mainly through estrogen receptor 1 (ESR1). The mouse vaginal epithelium cyclically exhibits cell proliferation and differentiation in response to estrogen and provides a unique model for analyzing the homeostasis of stratified squamous epithelia. To address the role of ESR1-mediated tissue events during homeostasis, we analyzed mice with a vaginal epithelium-specific knockout of Esr1 driven by keratin 5-Cre (K5-Esr1KO). We show here that loss of epithelial ESR1 in the vagina resulted in aberrant epithelial cell proliferation in the suprabasal cell layers and led to failure of keratinized differentiation. Gene expression analysis showed that several known estrogen target genes, including erbB growth factor ligands, were not induced by estrogen in the K5-Esr1KO mouse vagina. Organ culture experiments revealed that the addition of erbB growth factor ligands, such as amphiregulin, could activate keratinized differentiation in the absence of epithelial ESR1. Thus, epithelial ESR1 integrates estrogen and growth factor signaling to mediate regulation of cell proliferation in squamous differentiation, and our results provide new insights into estrogen-mediated homeostasis in female reproductive organs.

Epithelial estrogen receptor 1 intrinsically mediates squamous differentiation in the mouse vagina

PubMed Central

Miyagawa, Shinichi; Iguchi, Taisen

2015-01-01

Estrogen-mediated actions in female reproductive organs are tightly regulated, mainly through estrogen receptor 1 (ESR1). The mouse vaginal epithelium cyclically exhibits cell proliferation and differentiation in response to estrogen and provides a unique model for analyzing the homeostasis of stratified squamous epithelia. To address the role of ESR1-mediated tissue events during homeostasis, we analyzed mice with a vaginal epithelium-specific knockout of Esr1 driven by keratin 5-Cre (K5-Esr1KO). We show here that loss of epithelial ESR1 in the vagina resulted in aberrant epithelial cell proliferation in the suprabasal cell layers and led to failure of keratinized differentiation. Gene expression analysis showed that several known estrogen target genes, including erbB growth factor ligands, were not induced by estrogen in the K5-Esr1KO mouse vagina. Organ culture experiments revealed that the addition of erbB growth factor ligands, such as amphiregulin, could activate keratinized differentiation in the absence of epithelial ESR1. Thus, epithelial ESR1 integrates estrogen and growth factor signaling to mediate regulation of cell proliferation in squamous differentiation, and our results provide new insights into estrogen-mediated homeostasis in female reproductive organs. PMID:26438838

Lifespan analysis of brain development, gene expression and behavioral phenotypes in the Ts1Cje, Ts65Dn and Dp(16)1/Yey mouse models of Down syndrome.

PubMed

Aziz, Nadine M; Guedj, Faycal; Pennings, Jeroen L A; Olmos-Serrano, Jose Luis; Siegel, Ashley; Haydar, Tarik F; Bianchi, Diana W

2018-06-12

Down syndrome (DS) results from triplication of human chromosome 21. Neuropathological hallmarks of DS include atypical central nervous system development that manifests prenatally and extends throughout life. As a result, individuals with DS exhibit cognitive and motor deficits, and have delays in achieving developmental milestones. To determine whether different mouse models of DS recapitulate the human prenatal and postnatal phenotypes, here, we directly compared brain histogenesis, gene expression and behavior over the lifespan of three cytogenetically distinct mouse models of DS: Ts1Cje, Ts65Dn and Dp(16)1/Yey. Histological data indicated that Ts65Dn mice were the most consistently affected with respect to somatic growth, neurogenesis and brain morphogenesis. Embryonic and adult gene expression results showed that Ts1Cje and Ts65Dn brains had considerably more differentially expressed (DEX) genes compared with Dp(16)1/Yey mice, despite the larger number of triplicated genes in the latter model. In addition, DEX genes showed little overlap in identity and chromosomal distribution in the three models, leading to dissimilarities in affected functional pathways. Perinatal and adult behavioral testing also highlighted differences among the models in their abilities to achieve various developmental milestones and perform hippocampal- and motor-based tasks. Interestingly, Dp(16)1/Yey mice showed no abnormalities in prenatal brain phenotypes, yet they manifested behavioral deficits starting at postnatal day 15 that continued through adulthood. In contrast, Ts1Cje mice showed mildly abnormal embryonic brain phenotypes, but only select behavioral deficits as neonates and adults. Altogether, our data showed widespread and unexpected fundamental differences in behavioral, gene expression and brain development phenotypes between these three mouse models. Our findings illustrate unique limitations of each model when studying aspects of brain development and function in DS. This work helps to inform model selection in future studies investigating how observed neurodevelopmental abnormalities arise, how they contribute to cognitive impairment, and when testing therapeutic molecules to ameliorate the intellectual disability associated with DS.This article has an associated First Person interview with the first author of the paper. © 2018. Published by The Company of Biologists Ltd.

Genomic Organization of the Murine Miller–Dieker/Lissencephaly Region: Conservation of Linkage with the Human Region

PubMed Central

Hirotsune, Shinji; Pack, Svetlana D.; Chong, Samuel S.; Robbins, Christiane M.; Pavan, William J.; Ledbetter, David H.; Wynshaw-Boris, Anthony

1997-01-01

Several human syndromes are associated with haploinsufficiency of chromosomal regions secondary to microdeletions. Isolated lissencephaly sequence (ILS), a human developmental disease characterized by a smooth cerebral surface (classical lissencephaly) and microscopic evidence of incomplete neuronal migration, is often associated with small deletions or translocations at chromosome 17p13.3. Miller–Dieker syndrome (MDS) is associated with larger deletions of 17p13.3 and consists of classical lissencephaly with additional phenotypes including facial abnormalities. We have isolated the murine homologs of three genes located inside and outside the MDS region: Lis1, Mnt/Rox, and 14-3-3ε. These genes are all located on mouse chromosome 11B2, as determined by metaphase FISH, and the relative order and approximate gene distance was determined by interphase FISH analysis. The transcriptional orientation and intergenic distance of Lis1 and Mnt/Rox were ascertained by fragmentation analysis of a mouse yeast artificial chromosome containing both genes. To determine the distance and orientation of 14-3-3ε with respect to Lis1 and Mnt/Rox, we introduced a super-rare cutter site (VDE) that is unique in the mouse genome into 14-3-3ε by gene targeting. Using the introduced VDE site, the orientation of this gene was determined by pulsed field gel electrophoresis and Southern blot analysis. Our results demonstrate that the MDS region is conserved between human and mouse. This conservation of linkage suggests that the mouse can be used to model microdeletions that occur in ILS and MDS. PMID:9199935

Anxiety- rather than depression-like behavior is associated with adult neurogenesis in a female mouse model of higher trait anxiety- and comorbid depression-like behavior

PubMed Central

Sah, A; Schmuckermair, C; Sartori, S B; Gaburro, S; Kandasamy, M; Irschick, R; Klimaschewski, L; Landgraf, R; Aigner, L; Singewald, N

2012-01-01

Adult neurogenesis has been implicated in affective disorders and the action of antidepressants (ADs) although the functional significance of this association is still unclear. The use of animal models closely mimicking human comorbid affective and anxiety disorders seen in the majority of patients should provide relevant novel information. Here, we used a unique genetic mouse model displaying higher trait anxiety (HAB) and comorbid depression-like behavior. We demonstrate that HABs have a lower rate of hippocampal neurogenesis and impaired functional integration of newly born neurons as compared with their normal anxiety/depression-like behavior (NAB) controls. In HABs, chronic treatment with the AD fluoxetine alleviated their higher depression-like behavior and protected them from relapse for 3 but not 7 weeks after discontinuation of the treatment without affecting neurogenesis. Similar to what has been observed in depressed patients, fluoxetine treatment induced anxiogenic-like effects during the early treatment phase in NABs along with a reduction in neurogenesis. On the other hand, treatment with AD drugs with a particularly strong anxiolytic component, namely the neurokinin-1-receptor-antagonist L-822 429 or tianeptine, increased the reduced rate of neurogenesis in HABs up to NAB levels. In addition, challenge-induced hypoactivation of dentate gyrus (DG) neurons in HABs was normalized by all three drugs. Overall, these data suggest that AD-like effects in a psychopathological mouse model are commonly associated with modulation of DG hypoactivity but not neurogenesis, suggesting normalization of hippocampal hypoactivity as a neurobiological marker indicating successful remission. Finally, rather than to higher depression-related behavior, neurogenesis seems to be linked to pathological anxiety. PMID:23047242

Magnetic resonance imaging of disease progression and resolution in a transgenic mouse model of pulmonary fibrosis.

PubMed

Cleveland, Zackary I; Zhou, Yu M; Akinyi, Teckla G; Dunn, R Scott; Davidson, Cynthia R; Guo, Jinbang; Woods, Jason C; Hardie, William D

2017-04-01

Pulmonary fibrosis contributes to morbidity and mortality in a range of diseases, and there are no approved therapies for reversing its progression. To understand the mechanisms underlying pulmonary fibrosis and assess potential therapies, mouse models are central to basic and translational research. Unfortunately, metrics commonly used to assess murine pulmonary fibrosis require animals to be grouped and euthanized, increasing experimental difficulty and cost. We examined the ability of magnetic resonance imaging (MRI) to noninvasively assess lung fibrosis progression and resolution in a doxycycline (Dox) regulatable, transgenic mouse model that overexpresses transforming growth factor-α (TGF-α) under control of a lung-epithelial-specific promoter. During 7 wk of Dox treatment, fibrotic lesions were readily observed as high-signal tissue. Mean weighted signal and percent signal volume were found to be the most robust MRI-derived measures of fibrosis, and these metrics correlated significantly with pleural thickness, histology scores, and hydroxyproline content ( R  = 0.75-0.89). When applied longitudinally, percent high signal volume increased by 1.5% wk -1 ( P < 0.001) and mean weighted signal increased at a rate of 0.0065 wk -1 ( P = 0.0062). Following Dox treatment, lesions partially resolved, with percent high signal volume decreasing by -3.2% wk -1 ( P = 0.0034) and weighted mean signal decreasing at -0.015 wk -1 ( P = 0.0028). Additionally, longitudinal MRI revealed dynamic remodeling in a subset of lesions, a previously unobserved behavior in this model. These results demonstrate MRI can noninvasively assess experimental lung fibrosis progression and resolution and provide unique insights into its pathobiology. Copyright © 2017 the American Physiological Society.

The mouse cerebellar cortex in organotypic slice cultures: an in vitro model to analyze the consequences of mutations and pathologies on neuronal survival, development, and function.

PubMed

Lonchamp, Etienne; Dupont, Jean-Luc; Beekenkamp, Huguette; Poulain, Bernard; Bossu, Jean-Louis

2006-01-01

Thin acute slices and dissociated cell cultures taken from different parts of the brain have been widely used to examine the function of the nervous system, neuron-specific interactions, and neuronal development (specifically, neurobiology, neuropharmacology, and neurotoxicology studies). Here, we focus on an alternative in vitro model: brain-slice cultures in roller tubes, initially introduced by Beat Gähwiler for studies with rats, that we have recently adapted for studies of mouse cerebellum. Cultured cerebellar slices afford many of the advantages of dissociated cultures of neurons and thin acute slices. Organotypic slice cultures were established from newborn or 10-15-day-old mice. After 3-4 weeks in culture, the slices flattened to form a cell monolayer. The main types of cerebellar neurons could be identified with immunostaining techniques, while their electrophysiological properties could be easily characterized with the patch-clamp recording technique. When slices were taken from newborn mice and cultured for 3 weeks, aspects of the cerebellar development were displayed. A functional neuronal network was established despite the absence of mossy and climbing fibers, which are the two excitatory afferent projections to the cerebellum. When slices were made from 10-15-day-old mice, which are at a developmental stage when cerebellum organization is almost established, the structure and neuronal pathways were intact after 3-4 weeks in culture. These unique characteristics make organotypic slice cultures of mouse cerebellar cortex a valuable model for analyzing the consequences of gene mutations that profoundly alter neuronal function and compromise postnatal survival.

In vivo biodistribution of CNTs using a BALB/c mouse experimental model.

PubMed

Fufă, Mariana Oana Mihaela; Mihaiescu, Dan Eduard; Mogoantă, Laurenţiu; Bălşeanu, Tudor Adrian; Mogoşanu, George Dan; Grumezescu, Alexandru Mihai; Bolocan, Alexandra

2015-01-01

Due to their unique behaviors, carbon nanotubes (CNTs)-based systems meet essential requirements for modern applications, such as electronics, optics, photovoltaics, fuel cells, aerospace engineering, military and biomedical applications. CNTs biocompatibility and toxic effects were assessed both in vitro and in vivo, in terms of hemocompatibility, cytocompatibility, immunoreactions and genetic behavior. The aim of this paper is to evaluate the in vivo biodistribution and biocompatibility of carbon nanopowder synthesized by plasma processing, using a BALB/c mouse experimental model. Three months old BALB/c mice were aseptically injected with 100 μL of 1 mg/mL dispersions. The obtained carbon-based nano-systems were dispersed in saline solution and subsequently sterilized by using a 30 minutes treatment with UV irradiation. The reference mice were injected with 100 μL of saline. The mice were kept under standard conditions of light, temperature, humidity, food and water (ad libitum) before the vital organ harvest. The animal welfare was daily monitored. At two and 10 days after the inoculation, the animals were euthanized under general anesthesia, for the sampling of internal organs (brain, myocardium, pancreas, liver, lung, kidney and spleen). No animal died during the experiment. Brain, myocardium and pancreas were histologically normal, with no tissue damage, inflammatory infiltrate or inorganic deposits. CNTs were evidenced only in hepatic, renal, pulmonary and spleen tissue samples. Increased amounts of inorganic granular structures were reported after 10 days of treatment, when compared to the short-term (two days) inoculation. Our BALB/c mouse experimental model was found to be useful for the in vivo assessment of biodistribution and biocompatibility of CNTs.

What's So Special about FGF19-Unique Effects Reported on Skeletal Muscle Mass and Function.

PubMed

Glass, David J

2017-08-01

In a recent study published in Nature Medicine, Benoit et al. (2017) reported unique effects of FGF19 on mouse skeletal muscle: FGF19 induced skeletal muscle hypertrophy and blocked muscle atrophy, acting via FGF receptors and ßKlotho, while a related FGF21 hormone was ineffective. Copyright © 2017 Elsevier Inc. All rights reserved.

Deer mouse hemoglobin exhibits a lowered oxygen affinity owing to mobility of the E helix.

PubMed

Inoguchi, Noriko; Oshlo, Jake R; Natarajan, Chandrasekhar; Weber, Roy E; Fago, Angela; Storz, Jay F; Moriyama, Hideaki

2013-04-01

The deer mouse, Peromyscus maniculatus, exhibits altitude-associated variation in hemoglobin oxygen affinity. To examine the structural basis of this functional variation, the structure of the hemoglobin was solved. Recombinant hemoglobin was expressed in Escherichia coli and was purified by ion-exchange chromatography. Recombinant hemoglobin was crystallized by the hanging-drop vapor-diffusion method using polyethylene glycol as a precipitant. The obtained orthorhombic crystal contained two subunits in the asymmetric unit. The refined structure was interpreted as the aquo-met form. Structural comparisons were performed among hemoglobins from deer mouse, house mouse and human. In contrast to human hemoglobin, deer mouse hemoglobin lacks the hydrogen bond between α1Trp14 in the A helix and α1Thr67 in the E helix owing to the Thr67Ala substitution. In addition, deer mouse hemoglobin has a unique hydrogen bond at the α1β1 interface between residues α1Cys34 and β1Ser128.

Deer mouse hemoglobin exhibits a lowered oxygen affinity owing to mobility of the E helix

PubMed Central

Inoguchi, Noriko; Oshlo, Jake R.; Natarajan, Chandrasekhar; Weber, Roy E.; Fago, Angela; Storz, Jay F.; Moriyama, Hideaki

2013-01-01

The deer mouse, Peromyscus maniculatus, exhibits altitude-associated variation in hemoglobin oxygen affinity. To examine the structural basis of this functional variation, the structure of the hemoglobin was solved. Recombinant hemoglobin was expressed in Escherichia coli and was purified by ion-exchange chromatography. Recombinant hemoglobin was crystallized by the hanging-drop vapor-diffusion method using polyethylene glycol as a precipitant. The obtained orthorhombic crystal contained two subunits in the asymmetric unit. The refined structure was interpreted as the aquo-met form. Structural comparisons were performed among hemoglobins from deer mouse, house mouse and human. In contrast to human hemoglobin, deer mouse hemoglobin lacks the hydrogen bond between α1Trp14 in the A helix and α1Thr67 in the E helix owing to the Thr67Ala substitution. In addition, deer mouse hemoglobin has a unique hydrogen bond at the α1β1 interface between residues α1Cys34 and β1Ser128. PMID:23545644

Overexpression of miR-9 in mast cells is associated with invasive behavior and spontaneous metastasis

PubMed Central

2014-01-01

Background While microRNA (miRNA) expression is known to be altered in a variety of human malignancies contributing to cancer development and progression, the potential role of miRNA dysregulation in malignant mast cell disease has not been previously explored. The purpose of this study was to investigate the potential contribution of miRNA dysregulation to the biology of canine mast cell tumors (MCTs), a well-established spontaneous model of malignant mast cell disease. Methods We evaluated the miRNA expression profiles from biologically low-grade and biologically high-grade primary canine MCTs using real-time PCR-based TaqMan Low Density miRNA Arrays and performed real-time PCR to evaluate miR-9 expression in primary canine MCTs, malignant mast cell lines, and normal bone marrow-derived mast cells (BMMCs). Mouse mast cell lines and BMMCs were transduced with empty or pre-miR-9 expressing lentiviral constructs and cell proliferation, caspase 3/7 activity, and invasion were assessed. Transcriptional profiling of cells overexpressing miR-9 was performed using Affymetrix GeneChip Mouse Gene 2.0 ST arrays and real-time PCR was performed to validate changes in mRNA expression. Results Our data demonstrate that unique miRNA expression profiles correlate with the biological behavior of primary canine MCTs and that miR-9 expression is increased in biologically high grade canine MCTs and malignant cell lines compared to biologically low grade tumors and normal canine BMMCs. In transformed mouse malignant mast cell lines expressing either wild-type (C57) or activating (P815) KIT mutations and mouse BMMCs, miR-9 overexpression significantly enhanced invasion but had no effect on cell proliferation or apoptosis. Transcriptional profiling of normal mouse BMMCs and P815 cells possessing enforced miR-9 expression demonstrated dysregulation of several genes, including upregulation of CMA1, a protease involved in activation of matrix metalloproteases and extracellular matrix remodeling. Conclusions Our findings demonstrate that unique miRNA expression profiles correlate with the biological behavior of canine MCTs. Furthermore, dysregulation of miR-9 is associated with MCT metastasis potentially through the induction of an invasive phenotype, identifying a potentially novel pathway for therapeutic intervention. PMID:24517413

Submegabase Clusters of Unstable Tandem Repeats Unique to the Tla Region of Mouse T Haplotypes

PubMed Central

Uehara, H.; Ebersole, T.; Bennett, D.; Artzt, K.

1990-01-01

We describe here the identification and genomic organization of mouse t haplotype-specific elements (TSEs) 7.8 and 5.8 kb in length. The TSEs exist as submegabase-long clusters of tandem repeats localized in the Tla region of the major histocompatibility complex of all t haplotype chromosomes examined. In contrast, no such clusters were detected among 12 inbred strains of Mus musculus and other Mus species; thus, clusters of TSEs represent the first absolutely qualitative difference between t haplotypes and wild-type chromosomes. Pulsed field gel electrophoresis shows that the number of clusters, and the number of repeats in each cluster are extremely variable. Dramatic quantitative differences of TSEs uniquely distinguish every independent t haplotype from any other. The complete nucleotide sequence of one 7.8-kb TSE reveals significant homology to the ETn (a major transcript in the early embryo of the mouse), and some homologies to intracisternal A-particles and the mammary tumor virus env gene. Apart from the diagnostic relevance to t haplotypes, evolutionary and functional significances are discussed with respect to chromosome structure and genetic recombination. PMID:2076812

Abeta targets of the biosimilar antibodies of Bapineuzumab, Crenezumab, Solanezumab in comparison to an antibody against N‑truncated Abeta in sporadic Alzheimer disease cases and mouse models.

PubMed

Bouter, Yvonne; Lopez Noguerola, Jose Socrates; Tucholla, Petra; Crespi, Gabriela A N; Parker, Michael W; Wiltfang, Jens; Miles, Luke A; Bayer, Thomas A

2015-11-01

Solanezumab and Crenezumab are two humanized antibodies targeting Amyloid-β (Aβ) which are currently tested in multiple clinical trials for the prevention of Alzheimer's disease. However, there is a scientific discussion ongoing about the target engagement of these antibodies. Here, we report the immunohistochemical staining profiles of biosimilar antibodies of Solanezumab, Crenezumab and Bapineuzumab in human formalin-fixed, paraffin-embedded tissue and human fresh frozen tissue. Furthermore, we performed a direct comparative immunohistochemistry analysis of the biosimilar versions of the humanized antibodies in different mouse models including 5XFAD, Tg4-42, TBA42, APP/PS1KI, 3xTg. The staining pattern with these humanized antibodies revealed a surprisingly similar profile. All three antibodies detected plaques, cerebral amyloid angiopathy and intraneuronal Aβ in a similar fashion. Remarkably, Solanezumab showed a strong binding affinity to plaques. We also reaffirmed that Bapineuzumab does not recognize N-truncated or modified Aβ, while Solanezumab and Crenezumab do detect N-terminally modified Aβ peptides Aβ4-42 and pyroglutamate Aβ3-42. In addition, we compared the results with the staining pattern of the mouse NT4X antibody that recognizes specifically Aβ4-42 and pyroglutamate Aβ3-42, but not full-length Aβ1-42. In contrast to the biosimilar antibodies of Solanezumab, Crenezumab and Bapineuzumab, the murine NT4X antibody shows a unique target engagement. NT4X does barely cross-react with amyloid plaques in human tissue. It does, however, detect cerebral amyloid angiopathy in human tissue. In Alzheimer mouse models, NT4X detects intraneuronal Aβ and plaques comparable to the humanized antibodies. In conclusion, the biosimilar antibodies Solanezumab, Crenezumab and Bapineuzumab strongly react with amyloid plaques, which are in contrast to the NT4X antibody that hardly recognizes plaques in human tissue. Therefore, NT4X is the first of a new class of therapeutic antibodies.

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.

A Recombinant Adenovirus Expressing Ovine Interferon Tau Prevents Influenza Virus-Induced Lethality in Mice.

PubMed

Martín, V; Pascual, E; Avia, M; Rangel, G; de Molina, A; Alejo, A; Sevilla, N

2016-01-06

Ovine interferon tau (IFN-τ) is a unique type I interferon with low toxicity and a broad host range in vivo. We report the generation of a nonreplicative recombinant adenovirus expressing biologically active IFN-τ. Using the B6.A2G-Mx1 mouse model, we showed that single-dose intranasal administration of recombinant Ad5-IFN-τ can effectively prevent lethality and disease induced by highly virulent hv-PR8 influenza virus by activating the interferon response and preventing viral replication. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Mechanisms of Graft Rejection and Immune Regulation after Lung Transplant.

PubMed

Gauthier, Jason M; Li, Wenjun; Hsiao, Hsi-Min; Takahashi, Tsuyoshi; Arefanian, Saeed; Krupnick, Alexander S; Gelman, Andrew E; Kreisel, Daniel

2017-09-01

Outcomes after lung transplant lag behind those of other solid-organ transplants. A better understanding of the pathways that contribute to rejection and tolerance after lung transplant will be required to develop new therapeutic strategies that take into account the unique immunological features of lungs. Mechanistic immunological investigations in an orthotopic transplant model in the mouse have shed new light on immune responses after lung transplant. Here, we highlight that interactions between immune cells within pulmonary grafts shape their fate. These observations set lungs apart from other organs and help provide the conceptual framework for the development of lung-specific immunosuppression.

A dual-modality optical coherence tomography and selective plane illumination microscopy system for mouse embryonic imaging

NASA Astrophysics Data System (ADS)

Wu, Chen; Ran, Shihao; Le, Henry; Singh, Manmohan; Larina, Irina V.; Mayerich, David; Dickinson, Mary E.; Larin, Kirill V.

2017-02-01

Both optical coherence tomography (OCT) and selective plane illumination microscopy (SPIM) are frequently used in mouse embryonic research for high-resolution three-dimensional imaging. However, each of these imaging methods provide a unique and independent advantage: SPIM provides morpho-functional information through immunofluorescence and OCT provides a method for whole-embryo 3D imaging. In this study, we have combined rotational imaging OCT and SPIM into a single, dual-modality device to image E9.5 mouse embryos. The results demonstrate that the dual-modality setup is able to provide both anatomical and functional information simultaneously for more comprehensive tissue characterization.

Finding mouse models of human lymphomas and leukemia's using the Jackson laboratory mouse tumor biology database.

PubMed

Begley, Dale A; Sundberg, John P; Krupke, Debra M; Neuhauser, Steven B; Bult, Carol J; Eppig, Janan T; Morse, Herbert C; Ward, Jerrold M

2015-12-01

Many mouse models have been created to study hematopoietic cancer types. There are over thirty hematopoietic tumor types and subtypes, both human and mouse, with various origins, characteristics and clinical prognoses. Determining the specific type of hematopoietic lesion produced in a mouse model and identifying mouse models that correspond to the human subtypes of these lesions has been a continuing challenge for the scientific community. The Mouse Tumor Biology Database (MTB; http://tumor.informatics.jax.org) is designed to facilitate use of mouse models of human cancer by providing detailed histopathologic and molecular information on lymphoma subtypes, including expertly annotated, on line, whole slide scans, and providing a repository for storing information on and querying these data for specific lymphoma models. Copyright © 2015 Elsevier Inc. All rights reserved.

The Application of Humanized Mouse Models for the Study of Human Exclusive Viruses.

PubMed

Vahedi, Fatemeh; Giles, Elizabeth C; Ashkar, Ali A

2017-01-01

The symbiosis between humans and viruses has allowed human tropic pathogens to evolve intricate means of modulating the human immune response to ensure its survival among the human population. In doing so, these viruses have developed profound mechanisms that mesh closely with our human biology. The establishment of this intimate relationship has created a species-specific barrier to infection, restricting the virus-associated pathologies to humans. This specificity diminishes the utility of traditional animal models. Humanized mice offer a model unique to all other means of study, providing an in vivo platform for the careful examination of human tropic viruses and their interaction with human cells and tissues. These types of animal models have provided a reliable medium for the study of human-virus interactions, a relationship that could otherwise not be investigated without questionable relevance to humans.

Mouse models rarely mimic the transcriptome of human neurodegenerative diseases: A systematic bioinformatics-based critique of preclinical models.

PubMed

Burns, Terry C; Li, Matthew D; Mehta, Swapnil; Awad, Ahmed J; Morgan, Alexander A

2015-07-15

Translational research for neurodegenerative disease depends intimately upon animal models. Unfortunately, promising therapies developed using mouse models mostly fail in clinical trials, highlighting uncertainty about how well mouse models mimic human neurodegenerative disease at the molecular level. We compared the transcriptional signature of neurodegeneration in mouse models of Alzheimer׳s disease (AD), Parkinson׳s disease (PD), Huntington׳s disease (HD) and amyotrophic lateral sclerosis (ALS) to human disease. In contrast to aging, which demonstrated a conserved transcriptome between humans and mice, only 3 of 19 animal models showed significant enrichment for gene sets comprising the most dysregulated up- and down-regulated human genes. Spearman׳s correlation analysis revealed even healthy human aging to be more closely related to human neurodegeneration than any mouse model of AD, PD, ALS or HD. Remarkably, mouse models frequently upregulated stress response genes that were consistently downregulated in human diseases. Among potential alternate models of neurodegeneration, mouse prion disease outperformed all other disease-specific models. Even among the best available animal models, conserved differences between mouse and human transcriptomes were found across multiple animal model versus human disease comparisons, surprisingly, even including aging. Relative to mouse models, mouse disease signatures demonstrated consistent trends toward preserved mitochondrial function protein catabolism, DNA repair responses, and chromatin maintenance. These findings suggest a more complex and multifactorial pathophysiology in human neurodegeneration than is captured through standard animal models, and suggest that even among conserved physiological processes such as aging, mice are less prone to exhibit neurodegeneration-like changes. This work may help explain the poor track record of mouse-based translational therapies for neurodegeneration and provides a path forward to critically evaluate and improve animal models of human disease. Copyright © 2015 Elsevier B.V. All rights reserved.

Coexisting cholinergic and parahippocampal degeneration: a key to memory loss in dementia and a challenge for transgenic models?

PubMed

Cassel, Jean-Christophe; Mathis, Chantal; Majchrzak, Monique; Moreau, Pierre-Henri; Dalrymple-Alford, John C

2008-01-01

One century after Alzheimer's initial report, a variety of animal models of Alzheimer's disease (AD) are being used to mimic one or more pathological signs viewed as critical for the evolution of cognitive decline in dementia. Among the most common are, (a) traditional lesion models aimed at reproducing the degeneration of one of two key brain regions affected in AD, namely the cholinergic basal forebrain (CBF) and the transentorhinal region, and (b) transgenic mouse models aimed at reproducing AD histopathological hallmarks, namely amyloid plaques and neurofibrillary tangles. These models have provided valuable insights into the development and consequences of the pathology, but they have not consistently reproduced the severity of memory deficits exhibited in AD. The reasons for this lack of correspondence with the severity of expected deficits may include the limited replication of multiple neuropathology in potentially key brain regions. A recent lesion model in the rat found that severe memory impairment was obtained only when the two traditional lesions were combined together (i.e. conjoint CBF and entorhinal cortex lesions), indicative of a dramatic impact on cognitive function when there is coexisting, rather than isolated, damage in these two brain regions. It is proposed that combining AD transgenic mouse models with additional experimental damage to both the CBF and entorhinal regions might provide a unique opportunity to further understand the evolution of the disease and improve treatments of severe cognitive dysfunction in neurodegenerative dementias. (c) 2008 S. Karger AG, Basel

MHC variation sculpts individualized microbial communities that control susceptibility to enteric infection

PubMed Central

Kubinak, Jason L.; Stephens, W. Zac; Soto, Ray; Petersen, Charisse; Chiaro, Tyson; Gogokhia, Lasha; Bell, Rickesha; Ajami, Nadim J.; Petrosino, Joseph F.; Morrison, Linda; Potts, Wayne K.; Jensen, Peter E.; O'Connell, Ryan M.; Round, June L.

2015-01-01

The presentation of protein antigens on the cell surface by major histocompatibility complex (MHC) molecules coordinates vertebrate adaptive immune responses, thereby mediating susceptibility to a variety of autoimmune and infectious diseases. The composition of symbiotic microbial communities (the microbiota) is influenced by host immunity and can have a profound impact on host physiology. Here we use an MHC congenic mouse model to test the hypothesis that genetic variation at MHC genes among individuals mediates susceptibility to disease by controlling microbiota composition. We find that MHC genotype significantly influences antibody responses against commensals in the gut, and that these responses are correlated with the establishment of unique microbial communities. Transplantation experiments in germfree mice indicate that MHC-mediated differences in microbiota composition are sufficient to explain susceptibility to enteric infection. Our findings indicate that MHC polymorphisms contribute to defining an individual's unique microbial fingerprint that influences health. PMID:26494419

Serum-circulating miRNAs predict neuroblastoma progression in mouse model of high-risk metastatic disease.

PubMed

Ramraj, Satish Kumar; Aravindan, Sheeja; Somasundaram, Dinesh Babu; Herman, Terence S; Natarajan, Mohan; Aravindan, Natarajan

2016-04-05

Circulating miRNAs have momentous clinical relevance as prognostic biomarkers and in the progression of solid tumors. Recognizing novel candidates of neuroblastoma-specific circulating miRNAs would allow us to identify potential prognostic biomarkers that could predict the switch from favorable to high-risk metastatic neuroblastoma (HR-NB). Utilizing mouse models of favorable and HR-NB and whole miRnome profiling, we identified high serum levels of 34 and low levels of 46 miRNAs in animals with HR-NB. Preferential sequence homology exclusion of mouse miRNAs identified 25 (11 increased; 14 decreased) human-specific prognostic marker candidates, of which, 21 were unique to HR-NB. miRNA QPCR validated miRnome profile. Target analysis defined the candidate miRNAs' signal transduction flow-through and demonstrated their converged roles in tumor progression. miRNA silencing studies verified the function of select miRNAs on the translation of at least 14 target proteins. Expressions of critical targets that correlate tumor progression in tissue of multifarious organs identify the orchestration of HR-NB. Significant (>10 fold) increase in serum levels of miR-381, miR-548h, and miR-580 identify them as potential prognostic markers for neuroblastoma progression. For the first time, we identified serum-circulating miRNAs that predict the switch from favorable to HR-NB and, further imply that these miRNAs could play a functional role in tumor progression.

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.

A Chimera Analysis of Prestin Knockout Mice

PubMed Central

Cheatham, Mary Ann; Low-Zeddies, Sharon; Naik, Khurram; Edge, Roxanne; Zheng, Jing; Anderson, Charles T.; Dallos, Peter

2009-01-01

A chimera is a genetic composite containing a unique mix of cells derived from more than one zygote. This mouse model allows one to learn how cells of contrasting genotype functionally interact in vivo. Here we investigate the effect that different proportions of prestin-containing outer hair cells (OHC) have on cochlear amplification. In order to address this issue, we developed a prestin chimeric mouse in which both ROSA26 wildtype (WT) and prestin knockout (KO) genotypes are present in a single cochlea. The WT ROSA26 mice express a cell marker, allowing one to identify cells originating from the WT genome. Examination of cochlear tissue indicated that prestin chimeric mice demonstrate a mosaic in which mutant and normal OHCs interleave along the cochlear partition, similar to all other chimeric mouse models. The anatomical distribution of prestin-containing OHCs was compared with physiological data including thresholds and tuning curves for the compound action potential (CAP) recorded in anesthetized mice. Analysis of these measures did not reveal mixed phenotypes in which the distribution of prestin-containing OHCs impacted sensitivity and frequency selectivity to different degrees. However, by reducing the number of prestin-containing OHCs, phenotypes intermediate between WT and KO response patterns were obtained. Accordingly, we demonstrate a proportional reduction in sensitivity and in the tip length of CAP tuning curves as the number of OHCs derived from the KO genome increases, i.e., genotype ratio and phenotype are closely related. PMID:19776286

Selenium for the Prevention of Cutaneous Melanoma

PubMed Central

Cassidy, Pamela B.; Fain, Heidi D.; Cassidy, James P.; Tran, Sally M.; Moos, Philip J.; Boucher, Kenneth M.; Gerads, Russell; Florell, Scott R.; Grossman, Douglas; Leachman, Sancy A.

2013-01-01

The role of selenium (Se) supplementation in cancer prevention is controversial; effects often depend on the nutritional status of the subject and on the chemical form in which Se is provided. We used a combination of in vitro and in vivo models to study two unique therapeutic windows for intervention in the process of cutaneous melanomagenisis, and to examine the utility of two different chemical forms of Se for prevention and treatment of melanoma. We studied the effects of Se in vitro on UV-induced oxidative stress in melanocytes, and on apoptosis and cell cycle progression in melanoma cells. In vivo, we used the HGF transgenic mouse model of UV-induced melanoma to demonstrate that topical treatment with l-selenomethionine results in a significant delay in the time required for UV-induced melanoma development, but also increases the rate of growth of those tumors once they appear. In a second mouse model, we found that oral administration of high dose methylseleninic acid significantly decreases the size of human melanoma xenografts. Our findings suggest that modestly elevation of selenium levels in the skin might risk acceleration of growth of incipient tumors. Additionally, certain Se compounds administered at very high doses could have utility for the treatment of fully-malignant tumors or prevention of recurrence. PMID:23470450

Novel mouse model of colitis characterized by hapten-protein visualization.

PubMed

Ishiguro, Kazuhiro; Ando, Takafumi; Maeda, Osamu; Watanabe, Osamu; Goto, Hidemi

2010-09-01

Trinitrobenzene sulfonic acid (TNBS) and oxazolone are used to induce colitis for the investigation of inflammatory reactions in the colon. Although these chemicals are presumed to bind proteins in the colonic mucosa and then induce colitis as haptens, hapten-protein formation has not yet been confirmed in the colonic mucosa. We developed a mouse model of colitis characterized by hapten-protein visualization, using 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl), which emits fluorescence after binding to proteins. The enema of 1 mg/mL NBD-Cl induced severe diarrhea, rectal bleeding, and body weight reductions in BALB/c mice. Mucosal signs indicative of colitis, such as redness and swelling observed under stereomicroscopy or inflammatory cell infiltration and crypt-epithelium destruction under microscopy, were manifested around NBD-proteins visualized with fluorescence. Fluorescence microscopy showed the infiltration of F4/80+ cells around areas of NBD-proteins, and flow cytometry indicated the uptake of NBD-proteins by CD11b+ cells. We also found critical roles for T cells and interleukin-6 in colitis induction with NBD-proteins. NBD-Cl-induced colitis presents a unique model to study the relevance between hapten-protein formation and inflammatory reactions and offers a method to assess experimental interventions on colitis induction in the mucosa, where hapten-protein formation is confirmed.

Variable Behavior and Repeated Learning in Two Mouse Strains: Developmental and Genetic Contributions.

PubMed

Arnold, Megan A; Newland, M Christopher

2018-06-16

Behavioral inflexibility is often assessed using reversal learning tasks, which require a relatively low degree of response variability. No studies have assessed sensitivity to reinforcement contingencies that specifically select highly variable response patterns in mice, let alone in models of neurodevelopmental disorders involving limited response variation. Operant variability and incremental repeated acquisition (IRA) were used to assess unique aspects of behavioral variability of two mouse strains: BALB/c, a model of some deficits in ASD, and C57Bl/6. On the operant variability task, BALB/c mice responded more repetitively during adolescence than C57Bl/6 mice when reinforcement did not require variability but responded more variably when reinforcement required variability. During IRA testing in adulthood, both strains acquired an unchanging, performance sequence equally well. Strain differences emerged, however, after novel learning sequences began alternating with the performance sequence: BALB/c mice substantially outperformed C57Bl/6 mice. Using litter-mate controls, it was found that adolescent experience with variability did not affect either learning or performance on the IRA task in adulthood. These findings constrain the use of BALB/c mice as a model of ASD, but once again reveal this strain is highly sensitive to reinforcement contingencies and they are fast and robust learners. Copyright © 2018. Published by Elsevier B.V.

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

Early structural and functional plasticity alterations in a susceptibility period of DYT1 dystonia mouse striatum

PubMed Central

Maltese, Marta; Stanic, Jennifer; Tassone, Annalisa; Sciamanna, Giuseppe; Ponterio, Giulia; Vanni, Valentina; Martella, Giuseppina; Imbriani, Paola; Bonsi, Paola; Mercuri, Nicola Biagio

2018-01-01

The onset of abnormal movements in DYT1 dystonia is between childhood and adolescence, although it is unclear why clinical manifestations appear during this developmental period. Plasticity at corticostriatal synapses is critically involved in motor memory. In the Tor1a+/Δgag DYT1 dystonia mouse model, long-term potentiation (LTP) appeared prematurely in a critical developmental window in striatal spiny neurons (SPNs), while long-term depression (LTD) was never recorded. Analysis of dendritic spines showed an increase of both spine width and mature mushroom spines in Tor1a+/Δgag neurons, paralleled by an enhanced AMPA receptor (AMPAR) accumulation. BDNF regulates AMPAR expression during development. Accordingly, both proBDNF and BDNF levels were significantly higher in Tor1a+/Δgag mice. Consistently, antagonism of BDNF rescued synaptic plasticity deficits and AMPA currents. Our findings demonstrate that early loss of functional and structural synaptic homeostasis represents a unique endophenotypic trait during striatal maturation, promoting the appearance of clinical manifestations in mutation carriers. PMID:29504938

Large Polyglutamine Repeats Cause Muscle Degeneration in SCA17 Mice

PubMed Central

Huang, Shanshan; Yang, Su; Guo, Jifeng; Yan, Sen; Gaertig, Marta A.; Li, Shihua; Li, Xiao-Jiang

2015-01-01

SUMMARY In polyglutamine (polyQ) diseases, large polyQ repeats cause juvenile cases with different symptoms than adult-onset patients, who carry smaller expanded polyQ repeats. The mechanisms behind the differential pathology mediated by different polyQ repeat lengths remain unknown. By studying knock-in mouse models of spinal cerebellar ataxia-17 (SCA17), we found that a large polyQ (105 glutamines) in the TATA box-binding protein (TBP) preferentially causes muscle degeneration and reduces the expression of muscle-specific genes. Direct expression of TBP with different polyQ repeats in mouse muscle revealed that muscle degeneration is mediated only by the large polyQ repeats. Different polyQ repeats differentially alter TBP’s interaction with neuronal and muscle-specific transcription factors. As a result, the large polyQ repeat decreases the association of MyoD with TBP and DNA promoters. Our findings suggest that specific alterations in protein interactions by large polyQ repeats may account for the unique pathology in juvenile polyQ diseases. PMID:26387956

Models for preclinical studies in aging-related disorders: One is not for all

PubMed Central

Santulli, Gaetano; Borras, Consuelo; Bousquet, Jean; Calzà, Laura; Cano, Antonio; Illario, Maddalena; Franceschi, Claudio; Liotta, Giuseppe; Maggio, Marcello; Molloy, William D.; Montuori, Nunzia; O’Caoimh, Rónán; Orfila, Francesc; Rauter, Amelia P.; Santoro, Aurelia; Iaccarino, Guido

2015-01-01

Preclinical studies are essentially based on animal models of a particular disease. The primary purpose of preclinical efficacy studies is to support generalization of treatment–effect relationships to human subjects. Researchers aim to demonstrate a causal relationship between an investigational agent and a disease-related phenotype in such models. Numerous factors can muddle reliable inferences about such cause-effect relationships, including biased outcome assessment due to experimenter expectations. For instance, responses in a particular inbred mouse might be specific to the strain, limiting generalizability. Selecting well-justified and widely acknowledged model systems represents the best start in designing preclinical studies, especially to overcome any potential bias related to the model itself. This is particularly true in the research that focuses on aging, which carries unique challenges, mainly attributable to the fact that our already long lifespan makes designing experiments that use people as subjects extremely difficult and largely impractical. PMID:27042427

Massively parallel nanowell-based single-cell gene expression profiling.

PubMed

Goldstein, Leonard D; Chen, Ying-Jiun Jasmine; Dunne, Jude; Mir, Alain; Hubschle, Hermann; Guillory, Joseph; Yuan, Wenlin; Zhang, Jingli; Stinson, Jeremy; Jaiswal, Bijay; Pahuja, Kanika Bajaj; Mann, Ishminder; Schaal, Thomas; Chan, Leo; Anandakrishnan, Sangeetha; Lin, Chun-Wah; Espinoza, Patricio; Husain, Syed; Shapiro, Harris; Swaminathan, Karthikeyan; Wei, Sherry; Srinivasan, Maithreyan; Seshagiri, Somasekar; Modrusan, Zora

2017-07-07

Technological advances have enabled transcriptome characterization of cell types at the single-cell level providing new biological insights. New methods that enable simple yet high-throughput single-cell expression profiling are highly desirable. Here we report a novel nanowell-based single-cell RNA sequencing system, ICELL8, which enables processing of thousands of cells per sample. The system employs a 5,184-nanowell-containing microchip to capture ~1,300 single cells and process them. Each nanowell contains preprinted oligonucleotides encoding poly-d(T), a unique well barcode, and a unique molecular identifier. The ICELL8 system uses imaging software to identify nanowells containing viable single cells and only wells with single cells are processed into sequencing libraries. Here, we report the performance and utility of ICELL8 using samples of increasing complexity from cultured cells to mouse solid tissue samples. Our assessment of the system to discriminate between mixed human and mouse cells showed that ICELL8 has a low cell multiplet rate (< 3%) and low cross-cell contamination. We characterized single-cell transcriptomes of more than a thousand cultured human and mouse cells as well as 468 mouse pancreatic islets cells. We were able to identify distinct cell types in pancreatic islets, including alpha, beta, delta and gamma cells. Overall, ICELL8 provides efficient and cost-effective single-cell expression profiling of thousands of cells, allowing researchers to decipher single-cell transcriptomes within complex biological samples.

Simultaneous PET and Multispectral 3-Dimensional Fluorescence Optical Tomography Imaging System

PubMed Central

Li, Changqing; Yang, Yongfeng; Mitchell, Gregory S.; Cherry, Simon R.

2015-01-01

Integrated PET and 3-dimensional (3D) fluorescence optical tomography (FOT) imaging has unique and attractive features for in vivo molecular imaging applications. We have designed, built, and evaluated a simultaneous PET and 3D FOT system. The design of the FOT system is compatible with many existing small-animal PET scanners. Methods The 3D FOT system comprises a novel conical mirror that is used to view the whole-body surface of a mouse with an electron-multiplying charge-coupled device camera when a collimated laser beam is projected on the mouse to stimulate fluorescence. The diffusion equation was used to model the propagation of optical photons inside the mouse body, and 3D fluorescence images were reconstructed iteratively from the fluorescence intensity measurements measured from the surface of the mouse. Insertion of the conical mirror into the gantry of a small-animal PET scanner allowed simultaneous PET and 3D FOT imaging. Results The mutual interactions between PET and 3D FOT were evaluated experimentally. PET has negligible effects on 3D FOT performance. The inserted conical mirror introduces a reduction in the sensitivity and noise-equivalent count rate of the PET system and increases the scatter fraction. PET–FOT phantom experiments were performed. An in vivo experiment using both PET and FOT was also performed. Conclusion Phantom and in vivo experiments demonstrate the feasibility of simultaneous PET and 3D FOT imaging. The first in vivo simultaneous PET–FOT results are reported. PMID:21810591

Live imaging reveals a conserved role of fatty acid β-oxidation in early lymphatic development in zebrafish.

PubMed

Zecchin, Annalisa; Wong, Brian W; Tembuyser, Bieke; Souffreau, Joris; Van Nuffelen, An; Wyns, Sabine; Vinckier, Stefan; Carmeliet, Peter; Dewerchin, Mieke

2018-06-18

During embryonic development, lymphatic endothelial cells (LECs) differentiate from venous endothelial cells (VECs), a process that is tightly regulated by several genetic signals. While the aquatic zebrafish model is regularly used for studying lymphangiogenesis and offers the unique advantage of time-lapse video-imaging of lymphatic development, some aspects of lymphatic development in this model differ from those in the mouse. It therefore remained to be determined whether fatty acid β-oxidation (FAO), which we showed to regulate lymphatic formation in the mouse, also co-determines lymphatic development in this aquatic model. Here, we took advantage of the power of the zebrafish embryo model to visualize the earliest steps of lymphatic development through time-lapse video-imaging. By targeting zebrafish isoforms of carnitine palmitoyltransferase 1a (cpt1a), a rate controlling enzyme of FAO, with multiple morpholinos, we demonstrate that reducing CPT1A levels and FAO flux during zebrafish development impairs lymphangiogenic secondary sprouting, the initiation of lymphatic development in the zebrafish trunk, and the formation of the first lymphatic structures. These findings not only show evolutionary conservation of the importance of FAO for lymphatic development, but also suggest a role for FAO in co-regulating the process of VEC-to-LEC differentiation in zebrafish in vivo. Copyright © 2018 Elsevier Inc. All rights reserved.

System parameters for erythropoiesis control model: Comparison of normal values in human and mouse model

NASA Technical Reports Server (NTRS)

1979-01-01

The computer model for erythropoietic control was adapted to the mouse system by altering system parameters originally given for the human to those which more realistically represent the mouse. Parameter values were obtained from a variety of literature sources. Using the mouse model, the mouse was studied as a potential experimental model for spaceflight. Simulation studies of dehydration and hypoxia were performed. A comparison of system parameters for the mouse and human models is presented. Aside from the obvious differences expected in fluid volumes, blood flows and metabolic rates, larger differences were observed in the following: erythrocyte life span, erythropoietin half-life, and normal arterial pO2.

Antidiabetic screening of commercial botanical products in 3T3-L1 adipocytes and db/db mice.

PubMed

Babish, John G; Pacioretty, Linda M; Bland, Jeffrey S; Minich, Deanna M; Hu, Jeffrey; Tripp, Matthew L

2010-06-01

Numerous botanicals are purported to improve glucose metabolism and diabetic risk factors with varying degrees of supportive evidence. We investigated 203 commercially available botanical products representing 90 unique botanical species for effects on lipogenic activity in differentiating 3T3-L1 adipocytes. Anti-inflammatory activity of 21 of these products was further assessed in tumor necrosis factor alpha (TNFalpha)-stimulated, mature 3T3-L1 adipocytes. From these results, rho-isoalpha acids, Acacia nilotica bark, fennel, and wasabi were tested in the db/db mouse model. Fifty-nine percent of the 90 unique botanicals increased adipogenesis as did the standard troglitazone relative to the solvent controls. Botanical species with the greatest percentage of positive products were Centella asiatica, Panax quinquefolius, and Phyllanthus amarus at 100%, Vitis vinifera at 80%, Humulus lupulus at 71%, Aloe barbadensis at 66%, and Momordica charantia, Phaseolus vulgaris, and Punica granatum at 60%. All 21 subset samples inhibited TNFalpha-stimulated free fatty acid release and attenuated TNFalpha inhibition of adiponectin secretion. Both rho-isoalpha acids and A. nilotica reduced nonfasting glucose in the db/db mouse model, whereas A. nilotica also decreased nonfasting insulin levels. A post hoc analysis of the screening results indicated that the positive predictive value of the lipogenesis assay alone was 72%, while adding the criterion of a positive response in the anti-inflammatory assays increased this figure to 82%. Moreover, this large-scale evaluation demonstrates that antidiabetic, in vitro efficacy of botanicals is more a function of manufacturing or quality control differences than the presence of marker compounds and further underscores the need to develop functional as well as analytical bases for standardization of dietary supplements.

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

Li, Guodong; Department of Abdominal Surgery, Cancer treatment center, Fourth Affiliated Hospital of Harbin Medical University, Harbin; Lin, Wenwei

Farnesoid X receptor (FXR) is a ligand-activated nuclear receptor and serves as a key regulator to maintain health of the liver and intestine. Bile acids are endogenous ligands of FXR, and there are increasing efforts to identify FXR modulators to serve as biological probes and/or pharmaceutical agents. Natural FXR ligands isolated from plants may serve as models to synthesize novel FXR modulators. In this study, we demonstrated that epigallocatechin-3-gallate (EGCG), a major tea catechin, specifically and dose-dependently activates FXR. In addition, EGCG induced FXR target gene expression in vitro. Surprisingly, in a co-activator (SRC2) recruitment assay, we found that EGCGmore » does not recruit SRC2 to FXR, but it dose-dependently inhibits recruitment of SRC2 to FXR (IC{sub 50}, 1 μM) by GW6064, which is a potent FXR synthetic ligand. In addition, EGCG suppressed FXR target gene expression induced by either GW4064 or chenodeoxycholic acid in vitro. Furthermore, wild-type and FXR knockout mice treated with an acute dose of EGCG had induced mRNA expression in a subset of FXR target genes in the intestine but not in the liver. In conclusion, EGCG is a unique modulator of FXR in the intestine and may serve as an important model for future development of FXR modulators. -- Highlights: ► Epigallocatechin-3-gallate (EGCG) is a unique farnesoid X receptor (FXR) modulator. ► EGCG activates FXR by itself, but inhibits FXR transactivation by other agonists. ► Low concentration of EGCG activates FXR in mouse intestine but not liver. ► EGCG activates FXR to induce a subset of FXR target genes in mouse intestine.« less

Reverse-translational biomarker validation of Abnormal Repetitive Behaviors in mice: an illustration of the 4P's modeling approach

PubMed Central

Garner, Joseph P.; Thogerson, Collette M.; Dufour, Brett D.; Würbel, Hanno; Murray, James D.; Mench, Joy A.

2011-01-01

The NIMH's new strategic plan, with its emphasis on the “4P's” (Prediction, Preemption, Personalization, & Populations) and biomarker-based medicine requires a radical shift in animal modeling methodology. In particular 4P's models will be non-determinant (i.e. disease severity will depend on secondary environmental and genetic factors); and validated by reverse-translation of animal homologues to human biomarkers. A powerful consequence of the biomarker approach is that different closely-related disorders have a unique fingerprint of biomarkers. Animals can be validated as a highly-specific model of a single disorder by matching this `fingerprint'; or as a model of a symptom seen in multiple disorders by matching common biomarkers. Here we illustrate this approach with two Abnormal Repetitive Behaviors (ARBs) in mice: stereotypies; and barbering (hair pulling). We developed animal versions of the neuropsychological biomarkers that distinguish human ARBs, and tested the fingerprint of the different mouse ARBs. As predicted, the two mouse ARBs were associated with different biomarkers. Both barbering and stereotypy could be discounted as models of OCD (even though they are widely used as such), due to the absence of limbic biomarkers which are characteristic of OCD and hence are necessary for a valid model. Conversely barbering matched the fingerprint of trichotillomania (i.e. selective deficits in set-shifting), suggesting it may be a highly specific model of this disorder. In contrast stereotypies were correlated only with a biomarker (deficits in response shifting) correlated with stereotypies in multiple disorders, suggesting that animal stereotypies model stereotypies in multiple disorders. PMID:21219937

MD-2-mediated Ionic Interactions between Lipid A and TLR4 Are Essential for Receptor Activation*

PubMed Central

Meng, Jianmin; Lien, Egil; Golenbock, Douglas T.

2010-01-01

Lipopolysaccharide (LPS) activates innate immune responses through TLR4·MD-2. LPS binds to the MD-2 hydrophobic pocket and bridges the dimerization of two TLR4·MD-2 complexes to activate intracellular signaling. However, exactly how lipid A, the endotoxic moiety of LPS, activates myeloid lineage cells remains unknown. Lipid IVA, a tetra-acylated lipid A precursor, has been used widely as a model for lipid A activation. For unknown reasons, lipid IVA activates proinflammatory responses in rodent cells but inhibits the activity of LPS in human cells. Using stable TLR4-expressing cell lines and purified monomeric MD-2, as well as MD-2-deficient bone marrow-derived macrophages, we found that both mouse TLR4 and mouse MD-2 are required for lipid IVA activation. Computational studies suggested that unique ionic interactions exist between lipid IVA and TLR4 at the dimerization interface in the mouse complex only. The negatively charged 4′-phosphate on lipid IVA interacts with two positively charged residues on the opposing mouse, but not human, TLR4 (Lys367 and Arg434) at the dimerization interface. When replaced with their negatively charged human counterparts Glu369 and Gln436, mouse TLR4 was no longer responsive to lipid IVA. In contrast, human TLR4 gained lipid IVA responsiveness when ionic interactions were enabled by charge reversal at the dimerization interface, defining the basis of lipid IVA species specificity. Thus, using lipid IVA as a selective lipid A agonist, we successfully decoupled and coupled two sequential events required for intracellular signaling: receptor engagement and dimerization, underscoring the functional role of ionic interactions in receptor activation. PMID:20018893

Scanning Thin-Sheet Laser Imaging Microscopy Elucidates Details on Mouse Ear Development

PubMed Central

Kopecky, Benjamin; Johnson, Shane; Schmitz, Heather; Santi, Peter; Fritzsch, Bernd

2016-01-01

Background The mammalian inner ear is transformed from a flat placode into a three-dimensional (3D) structure with six sensory epithelia that allow for the perception of sound and both linear and angular acceleration. While hearing and balance problems are typically considered to be adult onset diseases, they may arise as a developmental perturbation to the developing ear. Future prevention of hearing or balance loss requires an understanding of how closely genetic mutations in model organisms reflect the human case, necessitating an objective multidimensional comparison of mouse ears with human ears that have comparable mutations in the same gene. Results Here, we present improved 3D analyses of normal murine ears during embryonic development using optical sections obtained through Thin-Sheet Laser Imaging Microscopy. We chronicle the transformation of an undifferentiated otic vesicle between mouse embryonic day 11.5 to a fully differentiated inner ear at postnatal day 15. Conclusions Our analysis of ear development provides new insights into ear development, enables unique perspectives into the complex development of the ear, and allows for the first full quantification of volumetric and linear aspects of ear growth. Our data provide the framework for future analysis of mutant phenotypes that are currently under-appreciated using only two dimensional renderings. PMID:22271591

Scanning thin-sheet laser imaging microscopy elucidates details on mouse ear development.

PubMed

Kopecky, Benjamin; Johnson, Shane; Schmitz, Heather; Santi, Peter; Fritzsch, Bernd

2012-03-01

The mammalian inner ear is transformed from a flat placode into a three-dimensional (3D) structure with six sensory epithelia that allow for the perception of sound and both linear and angular acceleration. While hearing and balance problems are typically considered to be adult onset diseases, they may arise as a developmental perturbation to the developing ear. Future prevention of hearing or balance loss requires an understanding of how closely genetic mutations in model organisms reflect the human case, necessitating an objective multidimensional comparison of mouse ears with human ears that have comparable mutations in the same gene. Here, we present improved 3D analyses of normal murine ears during embryonic development using optical sections obtained through Thin-Sheet Laser Imaging Microscopy. We chronicle the transformation of an undifferentiated otic vesicle between mouse embryonic day 11.5 to a fully differentiated inner ear at postnatal day 15. Our analysis of ear development provides new insights into ear development, enables unique perspectives into the complex development of the ear, and allows for the first full quantification of volumetric and linear aspects of ear growth. Our data provide the framework for future analysis of mutant phenotypes that are currently under-appreciated using only two dimensional renderings. Copyright © 2012 Wiley Periodicals, Inc.

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.

B-Cell Epitopes in GroEL of Francisella tularensis

PubMed Central

Lu, Zhaohua; Rynkiewicz, Michael J.; Madico, Guillermo; Li, Sheng; Yang, Chiou-Ying; Perkins, Hillary M.; Sompuram, Seshi R.; Kodela, Vani; Liu, Tong; Morris, Timothy; Wang, Daphne; Roche, Marly I.; Seaton, Barbara A.; Sharon, Jacqueline

2014-01-01

The chaperonin protein GroEL, also known as heat shock protein 60 (Hsp60), is a prominent antigen in the human and mouse antibody response to the facultative intracellular bacterium Francisella tularensis (Ft), the causative agent of tularemia. In addition to its presumed cytoplasmic location, FtGroEL has been reported to be a potential component of the bacterial surface and to be released from the bacteria. In the current study, 13 IgG2a and one IgG3 mouse monoclonal antibodies (mAbs) specific for FtGroEL were classified into eleven unique groups based on shared VH-VL germline genes, and seven crossblocking profiles revealing at least three non-overlapping epitope areas in competition ELISA. In a mouse model of respiratory tularemia with the highly pathogenic Ft type A strain SchuS4, the Ab64 and N200 IgG2a mAbs, which block each other’s binding to and are sensitive to the same two point mutations in FtGroEL, reduced bacterial burden indicating that they target protective GroEL B-cell epitopes. The Ab64 and N200 epitopes, as well as those of three other mAbs with different crossblocking profiles, Ab53, N3, and N30, were mapped by hydrogen/deuterium exchange–mass spectrometry (DXMS) and visualized on a homology model of FtGroEL. This model was further supported by its experimentally-validated computational docking to the X-ray crystal structures of Ab64 and Ab53 Fabs. The structural analysis and DXMS profiles of the Ab64 and N200 mAbs suggest that their protective effects may be due to induction or stabilization of a conformational change in FtGroEL. PMID:24968190

Nanocidals therapy for osteomyelitis

NASA Astrophysics Data System (ADS)

Qadri, Shahnaz Majid

Infection is a major medical problem that causes serious complications including patient death. The mortality rate of invasive infection has reduced significantly since the introduction of antibiotherapy. However, the resistance to antibiotic is becoming a serious medical problem that resulted in high medical cost. The overall aim of this study is to evaluate a potential inorganic route (metalo-antibiotic) to treat localized infections that require long-term antibiotic treatment combined with medical and surgical intervention. In this study osteomyelitis (bone infection) was selected as a model to evaluate the inorganic route to treat infection. Osteomyelitis is a progressive infection that could result in amputation and patient death. The metalo-antibiotics are faster to develop than antibiotics and have shown great efficacy against a wide range of bacterial infection. A unique composition of particles with ability to extend their residual efficacy on bacteria for an extended time compared to conventional antibiotics was synthesized and evaluated in this study. The in vitro experiments demonstrated the metalo-antibiotics to treat cellular internal infections without damaging the home cell. The in vivo toxicity experiments demonstrated a tolerance of the particles for doses that are 20 times higher than the anticipated treatment dose. A murine mouse model for osteomyelitis was developed. The efficacy of the metalo-antibiotics on the induced osteomyelitis was evaluated. A significant decrease in infection in the bones treated with nanoparticles was observed. By delivering optimal concentration of nanoparticles in mouse models there was no sign of pathology seen in mouse. Overall, this study has two main impacts: a) creation of inorganic routes to fight against bacterial infection particularly those requiring long-term antibiotic or surgical treatment b) reduction of critical technical risk through generation of pre-clinical data of the employment of inorganic antibacterial complexes.

A novel Phex mutation in a new mouse model of hypophosphatemic rickets.

PubMed

Owen, Celeste; Chen, Frieda; Flenniken, Ann M; Osborne, Lucy R; Ichikawa, Shoji; Adamson, S Lee; Rossant, Janet; Aubin, Jane E

2012-07-01

X-linked hypophosphatemic rickets (XLH) is a dominantly inherited disease characterized by renal phosphate wasting, aberrant vitamin D metabolism, and defective bone mineralization. It is known that XLH in humans and in certain mouse models is caused by inactivating mutations in PHEX/Phex (phosphate-regulating gene with homologies to endopeptidases on the X chromosome). By a genome-wide N-ethyl-N-nitrosourea (ENU)-induced mutagenesis screen in mice, we identified a dominant mouse mutation that exhibits the classic clinical manifestations of XLH, including growth retardation, skeletal abnormalities (rickets/osteomalacia), hypophosphatemia, and increased serum alkaline phosphatase (ALP) levels. Mapping and sequencing revealed that these mice carry a point mutation in exon 14 of the Phex gene that introduces a stop codon at amino acid 496 of the coding sequence (Phex(Jrt) also published as Phex(K496X) [Ichikawa et al., 2012]). Fgf23 mRNA expression as well as that of osteocalcin, bone sialoprotein, and matrix extracellular phosphoglycoprotein was upregulated in male mutant long bone, but that of sclerostin was unaffected. Although Phex mRNA is expressed in bone from mutant hemizygous male mice (Phex(Jrt)/Y mice), no Phex protein was detected in immunoblots of femoral bone protein. Stromal cultures from mutant bone marrow were indistinguishable from those of wild-type mice with respect to differentiation and mineralization. The ability of Phex(Jrt)/Y osteoblasts to mineralize and the altered expression levels of matrix proteins compared with the well-studied Hyp mice makes it a unique model with which to further explore the clinical manifestations of XLH and its link to FGF23 as well as to evaluate potential new therapeutic strategies. Copyright © 2012 Wiley Periodicals, Inc.

Distraction induced enterogenesis: a unique mouse model using polyethylene glycol.

PubMed

Okawada, Manabu; Maria, Haytham Mustafa; Teitelbaum, Daniel H

2011-09-01

Recent studies have demonstrated that the small intestine can be lengthened by applying mechanical forces to the bowel lumen-distraction-induced enterogenesis. However, the mechanisms which account for this growth are unknown, and might be best examined using a mouse model. The purpose of this study is to establish the feasibility of developing distractive-induced small bowel growth in mouse. Twelve-week old C57BL/6J mice had a jejunal segment taken out of continuity, and distended with polyethylene glycol (PEG: 3350 KDa); this group was compared with a control group without stretching. Segment length and diameter were measured intra-operatively and after 5 d. Villus height, crypt depth, and muscle thickness in the isolated segment were assessed. Rate of epithelial cell proliferation (5-bromo-2-deoxyuridine: BrdU incorporation) in crypts were also examined. The mucosal mRNA expression of targeted factors was performed to investigate potential mechanisms which might lead to distraction-induced enterogenesis. At harvest, the PEG-stretched group showed a significant increase in length and diameter versus controls. Villus height, crypt depth, and muscular layer thickness increased in the PEG group. The PEG group also showed significantly increased rates of epithelial cell proliferation versus controls. Real-time PCR showed a trend toward higher β-catenin and c-myc mRNA expression in the PEG-stretched group; however, this difference was not statistically significant. Radial distraction-induced enterogenesis with PEG is a viable method for increasing small intestinal length and diameter. This model may provide a new method for studying the mechanisms leading to distraction-induced enterogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Histology and ultrastructure of transitional changes in skin morphology in the juvenile and adult four-striped mouse (Rhabdomys pumilio).

PubMed

Stewart, Eranée; Ajao, Moyosore Salihu; Ihunwo, Amadi Ogonda

2013-01-01

The four-striped mouse has a grey to brown coloured coat with four characteristic dark stripes interspersed with three lighter stripes running along its back. The histological differences in the skin of the juvenile and adult mouse were investigated by Haematoxylin and Eosin and Masson Trichrome staining, while melanocytes in the skin were studied through melanin-specific Ferro-ferricyanide staining. The ultrastructure of the juvenile skin, hair follicles, and melanocytes was also explored. In both the juvenile and adult four-striped mouse, pigment-containing cells were observed in the dermis and were homogeneously dispersed throughout this layer. Apart from these cells, the histology of the skin of the adult four-striped mouse was similar to normal mammalian skin. In the juvenile four-striped mouse, abundant hair follicles of varying sizes were observed in the dermis and hypodermis, while hair follicles of similar size were only present in the dermis of adult four-striped mouse. Ultrastructural analysis of juvenile hair follicles revealed that the arrangement and differentiation of cellular layers were typical of a mammal. This study therefore provides unique transition pattern in the four-striped mouse skin morphology different from the textbook description of the normal mammalian skin.

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

The Mouse Tumor Biology Database: A Comprehensive Resource for Mouse Models of Human Cancer.

PubMed

Krupke, Debra M; Begley, Dale A; Sundberg, John P; Richardson, Joel E; Neuhauser, Steven B; Bult, Carol J

2017-11-01

Research using laboratory mice has led to fundamental insights into the molecular genetic processes that govern cancer initiation, progression, and treatment response. Although thousands of scientific articles have been published about mouse models of human cancer, collating information and data for a specific model is hampered by the fact that many authors do not adhere to existing annotation standards when describing models. The interpretation of experimental results in mouse models can also be confounded when researchers do not factor in the effect of genetic background on tumor biology. The Mouse Tumor Biology (MTB) database is an expertly curated, comprehensive compendium of mouse models of human cancer. Through the enforcement of nomenclature and related annotation standards, MTB supports aggregation of data about a cancer model from diverse sources and assessment of how genetic background of a mouse strain influences the biological properties of a specific tumor type and model utility. Cancer Res; 77(21); e67-70. ©2017 AACR . ©2017 American Association for Cancer Research.

Ferret and pig models of cystic fibrosis: prospects and promise for gene therapy.

PubMed

Yan, Ziying; Stewart, Zoe A; Sinn, Patrick L; Olsen, John C; Hu, Jim; McCray, Paul B; Engelhardt, John F

2015-03-01

Large animal models of genetic diseases are rapidly becoming integral to biomedical research as technologies to manipulate the mammalian genome improve. The creation of cystic fibrosis (CF) ferrets and pigs is an example of such progress in animal modeling, with the disease phenotypes in the ferret and pig models more reflective of human CF disease than mouse models. The ferret and pig CF models also provide unique opportunities to develop and assess the effectiveness of gene and cell therapies to treat affected organs. In this review, we examine the organ disease phenotypes in these new CF models and the opportunities to test gene therapies at various stages of disease progression in affected organs. We then discuss the progress in developing recombinant replication-defective adenoviral, adeno-associated viral, and lentiviral vectors to target genes to the lung and pancreas in ferrets and pigs, the two most affected organs in CF. Through this review, we hope to convey the potential of these new animal models for developing CF gene and cell therapies.

Principles and application of LIMS in mouse clinics.

PubMed

Maier, Holger; Schütt, Christine; Steinkamp, Ralph; Hurt, Anja; Schneltzer, Elida; Gormanns, Philipp; Lengger, Christoph; Griffiths, Mark; Melvin, David; Agrawal, Neha; Alcantara, Rafael; Evans, Arthur; Gannon, David; Holroyd, Simon; Kipp, Christian; Raj, Navis Pretheeba; Richardson, David; LeBlanc, Sophie; Vasseur, Laurent; Masuya, Hiroshi; Kobayashi, Kimio; Suzuki, Tomohiro; Tanaka, Nobuhiko; Wakana, Shigeharu; Walling, Alison; Clary, David; Gallegos, Juan; Fuchs, Helmut; de Angelis, Martin Hrabě; Gailus-Durner, Valerie

2015-10-01

Large-scale systemic mouse phenotyping, as performed by mouse clinics for more than a decade, requires thousands of mice from a multitude of different mutant lines to be bred, individually tracked and subjected to phenotyping procedures according to a standardised schedule. All these efforts are typically organised in overlapping projects, running in parallel. In terms of logistics, data capture, data analysis, result visualisation and reporting, new challenges have emerged from such projects. These challenges could hardly be met with traditional methods such as pen & paper colony management, spreadsheet-based data management and manual data analysis. Hence, different Laboratory Information Management Systems (LIMS) have been developed in mouse clinics to facilitate or even enable mouse and data management in the described order of magnitude. This review shows that general principles of LIMS can be empirically deduced from LIMS used by different mouse clinics, although these have evolved differently. Supported by LIMS descriptions and lessons learned from seven mouse clinics, this review also shows that the unique LIMS environment in a particular facility strongly influences strategic LIMS decisions and LIMS development. As a major conclusion, this review states that there is no universal LIMS for the mouse research domain that fits all requirements. Still, empirically deduced general LIMS principles can serve as a master decision support template, which is provided as a hands-on tool for mouse research facilities looking for a LIMS.

Roles of steroid receptor coactivator (SRC)-1 and transcriptional intermediary factor (TIF) 2 in androgen receptor activity in mice

PubMed Central

Ye, Xiangcang; Han, Sang Jun; Tsai, Sophia Y.; DeMayo, Francesco J.; Xu, Jianming; Tsai, Ming-Jer; O'Malley, Bert W.

2005-01-01

Genetic disruption of the steroid receptor coactivator (SRC)-1 and transcriptional intermediary factor (TIF)2/SRC-2 in mouse resulted in distinctive mutant phenotypes. To quantify their roles in the function of androgen receptor (AR) transcriptional activity in vivo, we generated a unique transgenic AR-reporter mouse and analyzed the cell-specific contributions of SRC-1 and TIF2 to the activity of AR in mouse testis. Transgenic AR-luciferase and transgenic AR-lacZ mice harbor a recombinant mouse AR gene, ARGAL4DBD, which is functionally coupled with a upstream activation sequence-mediated reporter gene (AR activity indicator). After characterization of these mice in terms of AR function, we further derived bigenic mice by crossing AR activity indicator mice with the SRC-1-/- or TIF2+/- mutant mice. Analyses of the resultant bigenic mice by in vivo imaging and luciferase assays showed that testicular AR activity was decreased significantly in those with the TIF2+/- mutation but not in the SRC-1+/- background, suggesting that TIF2 serves as the preferential coactivator for AR in testis. Immunohistological analysis confirmed that AR and TIF2 coexist in mouse testicular Sertoli cell nuclei under normal conditions. Although SRC-1 concentrates in Sertoli cell nuclei in the absence of TIF2, nuclear SRC-1 is not able to rescue AR activity in the TIF2 mutant background. Interestingly, SRC-1 appears to negatively influence AR activity, thereby counterbalancing the TIF2-stimulated AR activity. Our results provide unique in vivo insights to the multidimensional cell-type-specific interactions between AR and coregulators. PMID:15983373

Roles of steroid receptor coactivator (SRC)-1 and transcriptional intermediary factor (TIF) 2 in androgen receptor activity in mice.

PubMed

Ye, Xiangcang; Han, Sang Jun; Tsai, Sophia Y; DeMayo, Francesco J; Xu, Jianming; Tsai, Ming-Jer; O'Malley, Bert W

2005-07-05

Genetic disruption of the steroid receptor coactivator (SRC)-1 and transcriptional intermediary factor (TIF)2/SRC-2 in mouse resulted in distinctive mutant phenotypes. To quantify their roles in the function of androgen receptor (AR) transcriptional activity in vivo, we generated a unique transgenic AR-reporter mouse and analyzed the cell-specific contributions of SRC-1 and TIF2 to the activity of AR in mouse testis. Transgenic AR-luciferase and transgenic AR-lacZ mice harbor a recombinant mouse AR gene, AR(GAL4DBD), which is functionally coupled with a upstream activation sequence-mediated reporter gene (AR activity indicator). After characterization of these mice in terms of AR function, we further derived bigenic mice by crossing AR activity indicator mice with the SRC-1-/- or TIF2+/- mutant mice. Analyses of the resultant bigenic mice by in vivo imaging and luciferase assays showed that testicular AR activity was decreased significantly in those with the TIF2+/- mutation but not in the SRC-1+/- background, suggesting that TIF2 serves as the preferential coactivator for AR in testis. Immunohistological analysis confirmed that AR and TIF2 coexist in mouse testicular Sertoli cell nuclei under normal conditions. Although SRC-1 concentrates in Sertoli cell nuclei in the absence of TIF2, nuclear SRC-1 is not able to rescue AR activity in the TIF2 mutant background. Interestingly, SRC-1 appears to negatively influence AR activity, thereby counterbalancing the TIF2-stimulated AR activity. Our results provide unique in vivo insights to the multidimensional cell-type-specific interactions between AR and coregulators.

Somatic cell nuclear transfer: infinite reproduction of a unique diploid genome.

PubMed

Kishigami, Satoshi; Wakayama, Sayaka; Hosoi, Yoshihiko; Iritani, Akira; Wakayama, Teruhiko

2008-06-10

In mammals, a diploid genome of an individual following fertilization of an egg and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual ending. Even as cultured cells from the individual, they cannot normally proliferate in perpetuity because of the "Hayflick limit". However, Dolly, the sheep cloned from an adult mammary gland cell, changes this scenario. Somatic cell nuclear transfer (SCNT) enables us to produce offspring without germ cells, that is, to "passage" a unique diploid genome. Animal cloning has also proven to be a powerful research tool for reprogramming in many mammals, notably mouse and cow. The mechanism underlying reprogramming, however, remains largely unknown and, animal cloning has been inefficient as a result. More momentously, in addition to abortion and fetal mortality, some cloned animals display possible premature aging phenotypes including early death and short telomere lengths. Under these inauspicious conditions, is it really possible for SCNT to preserve a diploid genome? Delightfully, in mouse and recently in primate, using SCNT we can produce nuclear transfer ES cells (ntES) more efficiently, which can preserve the eternal lifespan for the "passage" of a unique diploid genome. Further, new somatic cloning technique using histone-deacetylase inhibitors has been developed which can significantly increase the previous cloning rates two to six times. Here, we introduce SCNT and its value as a preservation tool for a diploid genome while reviewing aging of cloned animals on cellular and individual levels.

Discovery of LY2457546: a multi-targeted anti-angiogenic kinase inhibitor with a novel spectrum of activity and exquisite potency in the acute myelogenous leukemia-Flt-3-internal tandem duplication mutant human tumor xenograft model.

PubMed

Burkholder, Timothy P; Clayton, Joshua R; Rempala, Mark E; Henry, James R; Knobeloch, John M; Mendel, David; McLean, Johnathan A; Hao, Yan; Barda, David A; Considine, Eileen L; Uhlik, Mark T; Chen, Yuefeng; Ma, Liandong; Bloem, Laura J; Akunda, Jacqueline K; McCann, Denis J; Sanchez-Felix, Manuel; Clawson, David K; Lahn, Michael M; Starling, James J

2012-06-01

LY2457546 is a potent and orally bioavailable inhibitor of multiple receptor tyrosine kinases involved in angiogenic and tumorigenic signalling. In biochemical and cellular assays, LY2457546 demonstrates potent activity against targets that include VEGFR2 (KDR), PDGFRβ, FLT-3, Tie-2 and members of the Eph family of receptors. With activities against both Tie2 and Eph receptors, LY2457546 possesses an activity profile that distinguishes it from multikinase inhibitors. When compared head to head with sunitinib, LY2457546 was more potent for inhibition of endothelial tube formation in an in vitro angiogenesis co-culture model with an intermittent treatment design. In vivo, LY2457546 inhibited VEGF-driven autophosphorylation of lung KDR in the mouse and rat in a dose and concentration dependent manner. LY2457546 was well tolerated and exhibited efficacy in a 13762 syngeneic rat mammary tumor model in both once and twice daily continuous dosing schedules and in mouse human tumor xenograft models of lung, colon, and prostate origin. Additionally, LY2457546 caused complete regression of well-established tumors in an acute myelogenous leukemia (AML) FLT3-ITD mutant xenograft tumor model. The observed efficacy that was displayed by LY2457546 in the AML FLT3-ITD mutant tumor model was superior to sunitinib when both were evaluated using equivalent doses normalized to in vivo inhibition of pKDR in mouse lung. LY2457546 was well tolerated in non-clinical toxicology studies conducted in rats and dogs. The majority of the toxicities observed were similar to those observed with other multi-targeted anti-angiogenic kinase inhibitors (MAKs) and included bone marrow hypocellularity, hair and skin depigmentation, cartilage dysplasia and lymphoid organ degeneration and necrosis. Thus, the unique spectrum of target activity, potent in vivo anti-tumor efficacy in a variety of rodent and human solid tumor models, exquisite potency against a clinically relevant model of AML, and non-clinical safety profile justify the advancement of LY2457546 into clinical testing.

Drug discovery in prostate cancer mouse models.

PubMed

Valkenburg, Kenneth C; Pienta, Kenneth J

2015-01-01

The mouse is an important, though imperfect, organism with which to model human disease and to discover and test novel drugs in a preclinical setting. Many experimental strategies have been used to discover new biological and molecular targets in the mouse, with the hopes of translating these discoveries into novel drugs to treat prostate cancer in humans. Modeling prostate cancer in the mouse, however, has been challenging, and often drugs that work in mice have failed in human trials. The authors discuss the similarities and differences between mice and men; the types of mouse models that exist to model prostate cancer; practical questions one must ask when using a mouse as a model; and potential reasons that drugs do not often translate to humans. They also discuss the current value in using mouse models for drug discovery to treat prostate cancer and what needs are still unmet in field. With proper planning and following practical guidelines by the researcher, the mouse is a powerful experimental tool. The field lacks genetically engineered metastatic models, and xenograft models do not allow for the study of the immune system during the metastatic process. There remain several important limitations to discovering and testing novel drugs in mice for eventual human use, but these can often be overcome. Overall, mouse modeling is an essential part of prostate cancer research and drug discovery. Emerging technologies and better and ever-increasing forms of communication are moving the field in a hopeful direction.

eGFP expression under the Uchl1 promoter labels corticospinal motor neurons and a subpopulation of degeneration resistant spinal motor neurons in ALS mouse models

NASA Astrophysics Data System (ADS)

Yasvoina, Marina V.

Current understanding of basic cellular and molecular mechanisms for motor neuron vulnerability during motor neuron disease initiation and progression is incomplete. The complex cytoarchitecture and cellular heterogeneity of the cortex and spinal cord greatly impedes our ability to visualize, isolate, and study specific neuron populations in both healthy and diseased states. We generated a novel reporter line, the Uchl1-eGFP mouse, in which cortical and spinal components of motor neuron circuitry are genetically labeled with eGFP under the Uchl1 promoter. A series of cellular and anatomical analyses combined with retrograde labeling, molecular marker expression, and electrophysiology were employed to determine identity of eGFP expressing cells in the motor cortex and the spinal cord of novel Uchl1-eGFP reporter mice. We conclude that eGFP is expressed in corticospinal motor neurons (CSMN) in the motor cortex and a subset of S-type alpha and gamma spinal motor neurons (SMN) in the spinal cord. hSOD1G93A and Alsin-/- mice, mouse models for amyotrophic lateral sclerosis (ALS), were bred to Uchl1-eGFP reporter mouse line to investigate the pathophysiology and underlying mechanisms of CSMN degeneration in vivo. Evidence suggests early and progressive degeneration of CSMN and SMN in the hSOD1G93A transgenic mice. We show an early increase of autophagosome formation in the apical dendrites of vulnerable CSMN in hSOD1G93A-UeGFP mice, which is localized to the apical dendrites. In addition, labeling S-type alpha and gamma SMN in the hSOD1G93A-UeGFP mice provide a unique opportunity to study basis of their resistance to degeneration. Mice lacking alsin show moderate clinical phenotype and mild CSMN axon degeneration in the spinal cord, which suggests vulnerability of CSMN. Therefore, we investigated the CSMN cellular and axon defects in aged Alsin-/- mice bred to Uchl1-eGFP reporter mouse line. We show that while CSMN are preserved and lack signs of degeneration, CSMN axons are vulnerable and show significant loss.

Fusimonas intestini gen. nov., sp. nov., a novel intestinal bacterium of the family Lachnospiraceae associated with diabetes in mice.

PubMed

Kusada, Hiroyuki; Kameyama, Keishi; Meng, Xian-Ying; Kamagata, Yoichi; Tamaki, Hideyuki

2017-12-22

Our previous study shows that an anaerobic intestinal bacterium strain AJ110941 P contributes to type 2 diabetes development in mice. Here we phylogenetically and physiologically characterized this unique mouse gut bacterium. The 16S rRNA gene analysis revealed that the strain belongs to the family Lachnospiraceae but shows low sequence similarities ( < 92.5%) to valid species, and rather formed a distinct cluster with uncultured mouse gut bacteria clones. In metagenomic database survey, the 16S sequence of AJ110941 P also matched with mouse gut-derived datasets (56% of total datasets) with > 99% similarity, suggesting that AJ110941 P -related bacteria mainly reside in mouse digestive tracts. Strain AJ110941 P shared common physiological traits (e.g., Gram-positive, anaerobic, mesophilic, and fermentative growth with carbohydrates) with relative species of the Lachnospiraceae. Notably, the biofilm-forming capacity was found in both AJ110941 P and relative species. However, AJ110941 P possessed far more strong ability to produce biofilm than relative species and formed unique structure of extracellular polymeric substances. Furthermore, AJ110941 P cells are markedly long fusiform-shaped rods (9.0-62.5 µm) with multiple flagella that have never been observed in any other Lachnospiraceae members. Based on the phenotypic and phylogenetic features, we propose a new genus and species, Fusimonas intestini gen. nov., sp. nov. for strain AJ110941 P (FERM BP-11443).

Nanoparticle targeted therapy against childhood acute lymphoblastic leukemia

NASA Astrophysics Data System (ADS)

Satake, Noriko; Lee, Joyce; Xiao, Kai; Luo, Juntao; Sarangi, Susmita; Chang, Astra; McLaughlin, Bridget; Zhou, Ping; Kenney, Elaina; Kraynov, Liliya; Arnott, Sarah; McGee, Jeannine; Nolta, Jan; Lam, Kit

2011-06-01

The goal of our project is to develop a unique ligand-conjugated nanoparticle (NP) therapy against childhood acute lymphoblastic leukemia (ALL). LLP2A, discovered by Dr. Kit Lam, is a high-affinity and high-specificity peptidomimetic ligand against an activated α4β1 integrin. Our study using 11 fresh primary ALL samples (10 precursor B ALL and 1 T ALL) showed that childhood ALL cells expressed activated α4β1 integrin and bound to LLP2A. Normal hematopoietic cells such as activated lymphocytes and monocytes expressed activated α4β1 integrin; however, normal hematopoietic stem cells showed low expression of α4β1 integrin. Therefore, we believe that LLP2A can be used as a targeted therapy for childhood ALL. The Lam lab has developed novel telodendrimer-based nanoparticles (NPs) which can carry drugs efficiently. We have also developed a human leukemia mouse model using immunodeficient NOD/SCID/IL2Rγ null mice engrafted with primary childhood ALL cells from our patients. LLP2A-conjugated NPs will be evaluated both in vitro and in vivo using primary leukemia cells and this mouse model. NPs will be loaded first with DiD near infra-red dye, and then with the chemotherapeutic agents daunorubicin or vincristine. Both drugs are mainstays of current chemotherapy for childhood ALL. Targeting properties of LLP2A-conjugated NPs will be evaluated by fluorescent microscopy, flow cytometry, MTS assay, and mouse survival after treatment. We expect that LLP2A-conjugated NPs will be preferentially delivered and endocytosed to leukemia cells as an effective targeted therapy.

An Acvr1 R206H knock-in mouse has fibrodysplasia ossificans progressiva

PubMed Central

Chakkalakal, Salin A.; Zhang, Deyu; Culbert, Andria L.; Convente, Michael R.; Caron, Robert J.; Wright, Alexander C.; Maidment, Andrew D.A.; Kaplan, Frederick S.; Shore, Eileen M.

2013-01-01

Fibrodysplasia ossificans progressiva (FOP; MIM #135100) is a debilitating genetic disorder of dysregulated cellular differentiation characterized by malformation of the great toes during embryonic skeletal development and by progressive heterotopic endochondral ossification post-natally. Patients with these classic clinical features of FOP have the identical heterozygous single nucleotide substitution (c.617G>A; R206H) in the gene encoding ACVR1/ALK2, a bone morphogenetic protein (BMP) type I receptor. Gene targeting was used to develop a knock-in mouse model for FOP (Acvr1R206H/+). Radiographic analysis of Acvr1R206H/+ chimeric mice revealed that this mutation induced malformed first digits in the hind limbs and post-natal extra-skeletal bone formation, recapitulating the human disease. Histological analysis of murine lesions showed inflammatory infiltration and apoptosis of skeletal muscle followed by robust formation of heterotopic bone through an endochondral pathway, identical to that seen in patients. Progenitor cells of a Tie2+ lineage participated in each stage of endochondral osteogenesis. We further determined that both wild-type and mutant cells are present within the ectopic bone tissue, an unexpected finding that indicates that although the mutation is necessary to induce the bone formation process, the mutation is not required for progenitor cell contribution to bone and cartilage. This unique knock-in mouse model provides novel insight into the genetic regulation of heterotopic ossification and establishes the first direct in vivo evidence that the R206H mutation in ACVR1 causes FOP. PMID:22508565

Increased stress reactivity is associated with cognitive deficits and decreased hippocampal brain-derived neurotrophic factor in a mouse model of affective disorders.

PubMed

Knapman, A; Heinzmann, J-M; Hellweg, R; Holsboer, F; Landgraf, R; Touma, C

2010-07-01

Cognitive deficits are a common feature of major depression (MD), with largely unknown biological underpinnings. In addition to the affective and cognitive symptoms of MD, a dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is commonly observed in these patients. Increased plasma glucocorticoid levels are known to render the hippocampus susceptible to neuronal damage. This structure is important for learning and memory, creating a potential link between HPA axis dysregulation and cognitive deficits in depression. In order to further elucidate how altered stress responsiveness may contribute to the etiology of MD, three mouse lines with high (HR), intermediate (IR), or low (LR) stress reactivity were generated by selective breeding. The aim of the present study was to investigate whether increased stress reactivity is associated with deficits in hippocampus-dependent memory tests. To this end, we subjected mice from the HR, IR, and LR breeding lines to tests of recognition memory, spatial memory, and depression-like behavior. In addition, measurements of brain-derived neurotrophic factor (BDNF) in the hippocampus and plasma of these animals were conducted. Our results demonstrate that HR mice exhibit hippocampus-dependent memory deficits along with decreased hippocampal, but not plasma, BDNF levels. Thus, the stress reactivity mouse lines are a promising animal model of the cognitive deficits in MD with the unique feature of a genetic predisposition for an altered HPA axis reactivity, which provides the opportunity to explore the progression of the symptoms of MD, predisposing genetic factors as well as new treatment strategies. Copyright 2009 Elsevier Ltd. All rights reserved.

Orthology for comparative genomics in the mouse genome database.

PubMed

Dolan, Mary E; Baldarelli, Richard M; Bello, Susan M; Ni, Li; McAndrews, Monica S; Bult, Carol J; Kadin, James A; Richardson, Joel E; Ringwald, Martin; Eppig, Janan T; Blake, Judith A

2015-08-01

The mouse genome database (MGD) is the model organism database component of the mouse genome informatics system at The Jackson Laboratory. MGD is the international data resource for the laboratory mouse and facilitates the use of mice in the study of human health and disease. Since its beginnings, MGD has included comparative genomics data with a particular focus on human-mouse orthology, an essential component of the use of mouse as a model organism. Over the past 25 years, novel algorithms and addition of orthologs from other model organisms have enriched comparative genomics in MGD data, extending the use of orthology data to support the laboratory mouse as a model of human biology. Here, we describe current comparative data in MGD and review the history and refinement of orthology representation in this resource.

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

Hair and skin sterols in normal mice and those with deficient dehydrosterol reductase (DHCR7), the enzyme associated with Smith-Lemli-Opitz syndrome.

PubMed

Serra, Montserrat; Matabosch, Xavier; Ying, Lee; Watson, Gordon; Shackleton, Cedric

2010-11-01

Our recent studies have focused on cholesterol synthesis in mouse models for 7-dehydrosterolreductase (DHCR7) deficiency, also known as Smith-Lemli-Opitz syndrome. Investigations of such mutants have relied on tissue and blood levels of the cholesterol precursor 7-dehydrocholesterol (7DHC) and its 8-dehydro isomer. In this investigation by gas chromatography/mass spectrometry (GC/MS) we have identified and quantified cholesterol and its precursors (7DHC, desmosterol, lathosterol, lanosterol and cholest-7,24-dien-3β-ol) in mouse hair. The components were characterized and their concentrations were compared to those found in mouse skin and serum. Hair appeared unique in that desmosterol was a major sterol component, almost matching in concentration cholesterol itself. In DHCR7 deficient mice, dehydrodesmosterol (DHD) was the dominant hair Δ(7) sterol. Mutant mouse hair had much higher concentrations of 7-dehydrosterols relative to cholesterol than did serum or tissue at all ages studied. The 7DHC/C ratio in hair was typically about sevenfold the value in serum or skin and the DHD/D ratio was 100× that of the serum 7DHC/C ratio. Mutant mice compensate for their DHCR7 deficiency with maturity, and the tissue and blood 7DHC/C become close to normal. That hair retains high relative concentrations of the dehydro precursors suggests that the apparent up-regulation of Dhcr7 seen in liver is slower to develop at the site of hair cholesterol synthesis. Copyright © 2010 Elsevier Ltd. All rights reserved.

Cyclophosphamide augments antitumor immunity: studies in an autochthonous prostate cancer model.

PubMed

Wada, Satoshi; Yoshimura, Kiyoshi; Hipkiss, Edward L; Harris, Tim J; Yen, Hung-Rong; Goldberg, Monica V; Grosso, Joseph F; Getnet, Derese; Demarzo, Angelo M; Netto, George J; Anders, Robert; Pardoll, Drew M; Drake, Charles G

2009-05-15

To study the immune response to prostate cancer, we developed an autochthonous animal model based on the transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse in which spontaneously developing tumors express influenza hemagglutinin as a unique, tumor-associated antigen. Our prior studies in these animals showed immunologic tolerance to hemagglutinin, mirroring the clinical situation in patients with cancer who are generally nonresponsive to their disease. We used this physiologically relevant animal model to assess the immunomodulatory effects of cyclophosphamide when administered in combination with an allogeneic, cell-based granulocyte-macrophage colony-stimulating factor-secreting cancer immunotherapy. Through adoptive transfer of prostate/prostate cancer-specific CD8 T cells as well as through studies of the endogenous T-cell repertoire, we found that cyclophosphamide induced a marked augmentation of the antitumor immune response. This effect was strongly dependent on both the dose and the timing of cyclophosphamide administration. Mechanistic studies showed that immune augmentation by cyclophosphamide was associated with a transient depletion of regulatory T cells in the tumor draining lymph nodes but not in the peripheral circulation. Interestingly, we also noted effects on dendritic cell phenotype; low-dose cyclophosphamide was associated with increased expression of dendritic cell maturation markers. Taken together, these data clarify the dose, timing, and mechanism of action by which immunomodulatory cyclophosphamide can be translated to a clinical setting in a combinatorial cancer treatment strategy.

Small constrained SP1-7 analogs bind to a unique site and promote anti-allodynic effects following systemic injection in mice.

PubMed

Jonsson, A; Fransson, R; Haramaki, Y; Skogh, A; Brolin, E; Watanabe, H; Nordvall, G; Hallberg, M; Sandström, A; Nyberg, F

2015-07-09

Previous results have shown that the substance P (SP) N-terminal fragment SP1-7 may attenuate hyperalgesia and produce anti-allodynia in animals using various experimental models for neuropathic pain. The heptapeptide was found to induce its effects through binding to and activating specific sites apart from any known neurokinin or opioid receptor. Furthermore, we have applied a medicinal chemistry program to develop lead compounds mimicking the effect of SP1-7. The present study was designed to evaluate the pharmacological effect of these compounds using the mouse spared nerve injury (SNI) model of chronic neuropathic pain. Also, as no comprehensive screen with the aim to identify the SP1-7 target has yet been performed we screened our lead compound H-Phe-Phe-NH2 toward a panel of drug targets. The extensive target screen, including 111 targets, did not reveal any hit for the binding site among a number of known receptors or enzymes involved in pain modulation. Our animal studies confirmed that SP1-7, but also synthetic analogs thereof, possesses anti-allodynic effects in the mouse SNI model of neuropathic pain. One of the lead compounds, a constrained H-Phe-Phe-NH2 analog, was shown to exhibit a significant anti-allodynic effect. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Regulation of the Embryonic Cell Cycle During Mammalian Preimplantation Development.

PubMed

Palmer, N; Kaldis, P

2016-01-01

The preimplantation development stage of mammalian embryogenesis consists of a series of highly conserved, regulated, and predictable cell divisions. This process is essential to allow the rapid expansion and differentiation of a single-cell zygote into a multicellular blastocyst containing cells of multiple developmental lineages. This period of development, also known as the germinal stage, encompasses several important developmental transitions, which are accompanied by dramatic changes in cell cycle profiles and dynamics. These changes are driven primarily by differences in the establishment and enforcement of cell cycle checkpoints, which must be bypassed to facilitate the completion of essential cell cycle events. Much of the current knowledge in this area has been amassed through the study of knockout models in mice. These mouse models are powerful experimental tools, which have allowed us to dissect the relative dependence of the early embryonic cell cycles on various aspects of the cell cycle machinery and highlight the extent of functional redundancy between members of the same gene family. This chapter will explore the ways in which the cell cycle machinery, their accessory proteins, and their stimuli operate during mammalian preimplantation using mouse models as a reference and how this allows for the usually well-defined stages of the cell cycle to be shaped and transformed during this unique and critical stage of development. © 2016 Elsevier Inc. All rights reserved.

Microbead-induced ocular hypertensive mouse model for screening and testing of aqueous production suppressants for glaucoma.

PubMed

Yang, Qiang; Cho, Kin-Sang; Chen, Huihui; Yu, Dekuang; Wang, Wan-Heng; Luo, Gang; Pang, Iok-Hou; Guo, Wenyi; Chen, Dong Feng

2012-06-20

To characterize the microbead-induced ocular hypertension (OHT) mouse model and investigate its potential use for preclinical screening and evaluation of ocular hypotensive agents, we tested the model's responses to major antiglaucoma drugs. Adult C57BL/6J mice were induced to develop OHT unilaterally by intracameral injection of microbeads. The effects of the most commonly used ocular hypotensive drugs, including timolol, brimonidine, brinzolamide, pilocarpine, and latanoprost, on IOP and glaucomatous neural damage were evaluated. Degeneration of retinal ganglion cells (RGCs) and optic nerve axons were quantitatively assessed using immunofluorescence labeling and histochemistry. Thickness of the ganglion cell complex (GCC) was also assessed with spectral-domain optical coherence tomography (SD-OCT). A microbead-induced OHT model promptly responded to drugs, such as timolol, brimonidine, and brinzolamide, that lower IOP through suppressing aqueous humor production and showed improved RGC and axon survival as compared to vehicle controls. Accordingly, SD-OCT detected significantly less reduction of GCC thickness in mice treated with all three aqueous production suppressants as compared to the vehicle contol-treated group. In contrast, drugs that increase aqueous outflow, such as pilocarpine and latanoprost, failed to decrease IOP in the microbead-induced OHT mice. Microbead-induced OHT mice carry dysfunctional aqueous outflow facility and therefore offer a unique model that allows selective screening of aqueous production suppressant antiglaucoma drugs or for studying the mechanisms regulating aqueous humor production. Our data set the stage for using GCC thickness assessed by SD-OCT as an imaging biomarker for noninvasive tracking of neuronal benefits of glaucoma therapy in this model.

Identification of a set of genes showing regionally enriched expression in the mouse brain

PubMed Central

D'Souza, Cletus A; Chopra, Vikramjit; Varhol, Richard; Xie, Yuan-Yun; Bohacec, Slavita; Zhao, Yongjun; Lee, Lisa LC; Bilenky, Mikhail; Portales-Casamar, Elodie; He, An; Wasserman, Wyeth W; Goldowitz, Daniel; Marra, Marco A; Holt, Robert A; Simpson, Elizabeth M; Jones, Steven JM

2008-01-01

Background The Pleiades Promoter Project aims to improve gene therapy by designing human mini-promoters (< 4 kb) that drive gene expression in specific brain regions or cell-types of therapeutic interest. Our goal was to first identify genes displaying regionally enriched expression in the mouse brain so that promoters designed from orthologous human genes can then be tested to drive reporter expression in a similar pattern in the mouse brain. Results We have utilized LongSAGE to identify regionally enriched transcripts in the adult mouse brain. As supplemental strategies, we also performed a meta-analysis of published literature and inspected the Allen Brain Atlas in situ hybridization data. From a set of approximately 30,000 mouse genes, 237 were identified as showing specific or enriched expression in 30 target regions of the mouse brain. GO term over-representation among these genes revealed co-involvement in various aspects of central nervous system development and physiology. Conclusion Using a multi-faceted expression validation approach, we have identified mouse genes whose human orthologs are good candidates for design of mini-promoters. These mouse genes represent molecular markers in several discrete brain regions/cell-types, which could potentially provide a mechanistic explanation of unique functions performed by each region. This set of markers may also serve as a resource for further studies of gene regulatory elements influencing brain expression. PMID:18625066

Identification of a set of genes showing regionally enriched expression in the mouse brain.

PubMed

D'Souza, Cletus A; Chopra, Vikramjit; Varhol, Richard; Xie, Yuan-Yun; Bohacec, Slavita; Zhao, Yongjun; Lee, Lisa L C; Bilenky, Mikhail; Portales-Casamar, Elodie; He, An; Wasserman, Wyeth W; Goldowitz, Daniel; Marra, Marco A; Holt, Robert A; Simpson, Elizabeth M; Jones, Steven J M

2008-07-14

The Pleiades Promoter Project aims to improve gene therapy by designing human mini-promoters (< 4 kb) that drive gene expression in specific brain regions or cell-types of therapeutic interest. Our goal was to first identify genes displaying regionally enriched expression in the mouse brain so that promoters designed from orthologous human genes can then be tested to drive reporter expression in a similar pattern in the mouse brain. We have utilized LongSAGE to identify regionally enriched transcripts in the adult mouse brain. As supplemental strategies, we also performed a meta-analysis of published literature and inspected the Allen Brain Atlas in situ hybridization data. From a set of approximately 30,000 mouse genes, 237 were identified as showing specific or enriched expression in 30 target regions of the mouse brain. GO term over-representation among these genes revealed co-involvement in various aspects of central nervous system development and physiology. Using a multi-faceted expression validation approach, we have identified mouse genes whose human orthologs are good candidates for design of mini-promoters. These mouse genes represent molecular markers in several discrete brain regions/cell-types, which could potentially provide a mechanistic explanation of unique functions performed by each region. This set of markers may also serve as a resource for further studies of gene regulatory elements influencing brain expression.

Modeling correction of severe urea cycle defects in the growing murine liver using a hybrid recombinant adeno-associated virus/piggyBac transposase gene delivery system.

PubMed

Cunningham, Sharon C; Siew, Susan M; Hallwirth, Claus V; Bolitho, Christine; Sasaki, Natsuki; Garg, Gagan; Michael, Iacovos P; Hetherington, Nicola A; Carpenter, Kevin; de Alencastro, Gustavo; Nagy, Andras; Alexander, Ian E

2015-08-01

Liver-targeted gene therapy based on recombinant adeno-associated viral vectors (rAAV) shows promising therapeutic efficacy in animal models and adult-focused clinical trials. This promise, however, is not directly translatable to the growing liver, where high rates of hepatocellular proliferation are accompanied by loss of episomal rAAV genomes and subsequently a loss in therapeutic efficacy. We have developed a hybrid rAAV/piggyBac transposon vector system combining the highly efficient liver-targeting properties of rAAV with stable piggyBac-mediated transposition of the transgene into the hepatocyte genome. Transposition efficiency was first tested using an enhanced green fluorescent protein expression cassette following delivery to newborn wild-type mice, with a 20-fold increase in stably gene-modified hepatocytes observed 4 weeks posttreatment compared to traditional rAAV gene delivery. We next modeled the therapeutic potential of the system in the context of severe urea cycle defects. A single treatment in the perinatal period was sufficient to confer robust and stable phenotype correction in the ornithine transcarbamylase-deficient Spf(ash) mouse and the neonatal lethal argininosuccinate synthetase knockout mouse. Finally, transposon integration patterns were analyzed, revealing 127,386 unique integration sites which conformed to previously published piggyBac data. Using a hybrid rAAV/piggyBac transposon vector system, we achieved stable therapeutic protection in two urea cycle defect mouse models; a clinically conceivable early application of this technology in the management of severe urea cycle defects could be as a bridging therapy while awaiting liver transplantation; further improvement of the system will result from the development of highly human liver-tropic capsids, the use of alternative strategies to achieve transient transposase expression, and engineered refinements in the safety profile of piggyBac transposase-mediated integration. © 2015 by the American Association for the Study of Liver Diseases.

Reverse-translational biomarker validation of Abnormal Repetitive Behaviors in mice: an illustration of the 4P's modeling approach.

PubMed

Garner, Joseph P; Thogerson, Collette M; Dufour, Brett D; Würbel, Hanno; Murray, James D; Mench, Joy A

2011-06-01

The NIMH's new strategic plan, with its emphasis on the "4P's" (Prediction, Pre-emption, Personalization, and Populations) and biomarker-based medicine requires a radical shift in animal modeling methodology. In particular 4P's models will be non-determinant (i.e. disease severity will depend on secondary environmental and genetic factors); and validated by reverse-translation of animal homologues to human biomarkers. A powerful consequence of the biomarker approach is that different closely related disorders have a unique fingerprint of biomarkers. Animals can be validated as a highly specific model of a single disorder by matching this 'fingerprint'; or as a model of a symptom seen in multiple disorders by matching common biomarkers. Here we illustrate this approach with two Abnormal Repetitive Behaviors (ARBs) in mice: stereotypies and barbering (hair pulling). We developed animal versions of the neuropsychological biomarkers that distinguish human ARBs, and tested the fingerprint of the different mouse ARBs. As predicted, the two mouse ARBs were associated with different biomarkers. Both barbering and stereotypy could be discounted as models of OCD (even though they are widely used as such), due to the absence of limbic biomarkers which are characteristic of OCD and hence are necessary for a valid model. Conversely barbering matched the fingerprint of trichotillomania (i.e. selective deficits in set-shifting), suggesting it may be a highly specific model of this disorder. In contrast stereotypies were correlated only with a biomarker (deficits in response shifting) correlated with stereotypies in multiple disorders, suggesting that animal stereotypies model stereotypies in multiple disorders. Copyright © 2011 Elsevier B.V. All rights reserved.

Engineering Biomaterial Properties for Central Nervous System Applications

NASA Astrophysics Data System (ADS)

Rivet, Christopher John

Biomaterials offer unique properties that are intrinsic to the chemistry of the material itself or occur as a result of the fabrication process; iron oxide nanoparticles are superparamagnetic, which enables controlled heating in the presence of an alternating magnetic field, and a hydrogel and electrospun fiber hybrid material provides minimally invasive placement of a fibrous, artificial extracellular matrix for tissue regeneration. Utilization of these unique properties towards central nervous system disease and dysfunction requires a thorough definition of the properties in concert with full biological assessment. This enables development of material-specific features to elicit unique cellular responses. Iron oxide nanoparticles are first investigated for material-dependent, cortical neuron cytotoxicity in vitro and subsequently evaluated for alternating magnetic field stimulation induced hyperthermia, emulating the clinical application for enhanced chemotherapy efficacy in glioblastoma treatment. A hydrogel and electrospun fiber hybrid material is first applied to a rat brain to evaluate biomaterial interface astrocyte accumulation as a function of hybrid material composition. The hybrid material is then utilized towards increasing functional engraftment of dopaminergic progenitor neural stem cells in a mouse model of Parkinson's disease. Taken together, these two scenarios display the role of material property characterization in development of biomaterial strategies for central nervous system repair and regeneration.

Genome-wide expression profiling of five mouse models identifies similarities and differences with human psoriasis.

PubMed

Swindell, William R; Johnston, Andrew; Carbajal, Steve; Han, Gangwen; Wohn, Christian; Lu, Jun; Xing, Xianying; Nair, Rajan P; Voorhees, John J; Elder, James T; Wang, Xiao-Jing; Sano, Shigetoshi; Prens, Errol P; DiGiovanni, John; Pittelkow, Mark R; Ward, Nicole L; Gudjonsson, Johann E

2011-04-04

Development of a suitable mouse model would facilitate the investigation of pathomechanisms underlying human psoriasis and would also assist in development of therapeutic treatments. However, while many psoriasis mouse models have been proposed, no single model recapitulates all features of the human disease, and standardized validation criteria for psoriasis mouse models have not been widely applied. In this study, whole-genome transcriptional profiling is used to compare gene expression patterns manifested by human psoriatic skin lesions with those that occur in five psoriasis mouse models (K5-Tie2, imiquimod, K14-AREG, K5-Stat3C and K5-TGFbeta1). While the cutaneous gene expression profiles associated with each mouse phenotype exhibited statistically significant similarity to the expression profile of psoriasis in humans, each model displayed distinctive sets of similarities and differences in comparison to human psoriasis. For all five models, correspondence to the human disease was strong with respect to genes involved in epidermal development and keratinization. Immune and inflammation-associated gene expression, in contrast, was more variable between models as compared to the human disease. These findings support the value of all five models as research tools, each with identifiable areas of convergence to and divergence from the human disease. Additionally, the approach used in this paper provides an objective and quantitative method for evaluation of proposed mouse models of psoriasis, which can be strategically applied in future studies to score strengths of mouse phenotypes relative to specific aspects of human psoriasis.

A quantitative method for defining high-arched palate using the Tcof1(+/-) mutant mouse as a model.

PubMed

Conley, Zachary R; Hague, Molly; Kurosaka, Hiroshi; Dixon, Jill; Dixon, Michael J; Trainor, Paul A

2016-07-15

The palate functions as the roof of the mouth in mammals, separating the oral and nasal cavities. Its complex embryonic development and assembly poses unique susceptibilities to intrinsic and extrinsic disruptions. Such disruptions may cause failure of the developing palatal shelves to fuse along the midline resulting in a cleft. In other cases the palate may fuse at an arch, resulting in a vaulted oral cavity, termed high-arched palate. There are many models available for studying the pathogenesis of cleft palate but a relative paucity for high-arched palate. One condition exhibiting either cleft palate or high-arched palate is Treacher Collins syndrome, a congenital disorder characterized by numerous craniofacial anomalies. We quantitatively analyzed palatal perturbations in the Tcof1(+/-) mouse model of Treacher Collins syndrome, which phenocopies the condition in humans. We discovered that 46% of Tcof1(+/-) mutant embryos and new born pups exhibit either soft clefts or full clefts. In addition, 17% of Tcof1(+/-) mutants were found to exhibit high-arched palate, defined as two sigma above the corresponding wild-type population mean for height and angular based arch measurements. Furthermore, palatal shelf length and shelf width were decreased in all Tcof1(+/-) mutant embryos and pups compared to controls. Interestingly, these phenotypes were subsequently ameliorated through genetic inhibition of p53. The results of our study therefore provide a simple, reproducible and quantitative method for investigating models of high-arched palate. Copyright © 2015 Elsevier Inc. All rights reserved.

A quantitative method for defining high-arched palate using the Tcof1+/− mutant mouse as a model

PubMed Central

Conley, Zachary R.; Hague, Molly; Kurosaka, Hiroshi; Dixon, Jill; Dixon, Michael J.; Trainor, Paul A.

2016-01-01

The palate functions as the roof of the mouth in mammals, separating the oral and nasal cavities. Its complex embryonic development and assembly poses unique susceptibilities to intrinsic and extrinsic disruptions. Such disruptions may cause failure of the developing palatal shelves to fuse along the midline resulting in a cleft. In other cases the palate may fuse at an arch, resulting in a vaulted oral cavity, termed high-arched palate. There are many models available for studying the pathogenesis of cleft palate but a relative paucity for high-arched palate. One condition exhibiting either cleft palate or high-arched palate is Treacher Collins syndrome, a congenital disorder characterized by numerous craniofacial anomalies. We quantitatively analyzed palatal perturbations in the Tcof1+/− mouse model of Treacher Collins syndrome, which phenocopies the condition in humans. We discovered that 46% of Tcof1+/− mutant embryos and new born pups exhibit either soft clefts or full clefts. In addition, 17% of Tcof1+/− mutants were found to exhibit high-arched palate, defined as two sigma above the corresponding wild-type population mean for height and angular based arch measurements. Furthermore, palatal shelf length and shelf width were decreased in all Tcof1+/− mutant embryos and pups compared to controls. Interestingly, these phenotypes were subsequently ameliorated through genetic inhibition of p53. The results of our study therefore provide a simple, reproducible and quantitative method for investigating models of high-arched palate. PMID:26772999

The caveolin-cavin system plays a conserved and critical role in mechanoprotection of skeletal muscle.

PubMed

Lo, Harriet P; Nixon, Susan J; Hall, Thomas E; Cowling, Belinda S; Ferguson, Charles; Morgan, Garry P; Schieber, Nicole L; Fernandez-Rojo, Manuel A; Bastiani, Michele; Floetenmeyer, Matthias; Martel, Nick; Laporte, Jocelyn; Pilch, Paul F; Parton, Robert G

2015-08-31

Dysfunction of caveolae is involved in human muscle disease, although the underlying molecular mechanisms remain unclear. In this paper, we have functionally characterized mouse and zebrafish models of caveolae-associated muscle disease. Using electron tomography, we quantitatively defined the unique three-dimensional membrane architecture of the mature muscle surface. Caveolae occupied around 50% of the sarcolemmal area predominantly assembled into multilobed rosettes. These rosettes were preferentially disassembled in response to increased membrane tension. Caveola-deficient cavin-1(-/-) muscle fibers showed a striking loss of sarcolemmal organization, aberrant T-tubule structures, and increased sensitivity to membrane tension, which was rescued by muscle-specific Cavin-1 reexpression. In vivo imaging of live zebrafish embryos revealed that loss of muscle-specific Cavin-1 or expression of a dystrophy-associated Caveolin-3 mutant both led to sarcolemmal damage but only in response to vigorous muscle activity. Our findings define a conserved and critical role in mechanoprotection for the unique membrane architecture generated by the caveolin-cavin system. © 2015 Lo et al.

The caveolin–cavin system plays a conserved and critical role in mechanoprotection of skeletal muscle

PubMed Central

Lo, Harriet P.; Nixon, Susan J.; Hall, Thomas E.; Cowling, Belinda S.; Ferguson, Charles; Morgan, Garry P.; Schieber, Nicole L.; Fernandez-Rojo, Manuel A.; Bastiani, Michele; Floetenmeyer, Matthias; Martel, Nick; Laporte, Jocelyn; Pilch, Paul F.

2015-01-01

Dysfunction of caveolae is involved in human muscle disease, although the underlying molecular mechanisms remain unclear. In this paper, we have functionally characterized mouse and zebrafish models of caveolae-associated muscle disease. Using electron tomography, we quantitatively defined the unique three-dimensional membrane architecture of the mature muscle surface. Caveolae occupied around 50% of the sarcolemmal area predominantly assembled into multilobed rosettes. These rosettes were preferentially disassembled in response to increased membrane tension. Caveola-deficient cavin-1−/− muscle fibers showed a striking loss of sarcolemmal organization, aberrant T-tubule structures, and increased sensitivity to membrane tension, which was rescued by muscle-specific Cavin-1 reexpression. In vivo imaging of live zebrafish embryos revealed that loss of muscle-specific Cavin-1 or expression of a dystrophy-associated Caveolin-3 mutant both led to sarcolemmal damage but only in response to vigorous muscle activity. Our findings define a conserved and critical role in mechanoprotection for the unique membrane architecture generated by the caveolin–cavin system. PMID:26323694

Cerebral vascular amyloid seeds drive amyloid β-protein fibril assembly with a distinct anti-parallel structure

PubMed Central

Xu, Feng; Fu, Ziao; Dass, Sharmila; Kotarba, AnnMarie E.; Davis, Judianne; Smith, Steven O.; Van Nostrand, William E.

2016-01-01

Cerebrovascular accumulation of amyloid β-protein (Aβ), a condition known as cerebral amyloid angiopathy (CAA), is a common pathological feature of patients with Alzheimer's disease. Familial Aβ mutations, such as Dutch-E22Q and Iowa-D23N, can cause severe cerebrovascular accumulation of amyloid that serves as a potent driver of vascular cognitive impairment and dementia. The distinctive features of vascular amyloid that underlie its unique pathological properties remain unknown. Here, we use transgenic mouse models producing CAA mutants (Tg-SwDI) or overproducing human wild-type Aβ (Tg2576) to demonstrate that CAA-mutant vascular amyloid influences wild-type Aβ deposition in brain. We also show isolated microvascular amyloid seeds from Tg-SwDI mice drive assembly of human wild-type Aβ into distinct anti-parallel β-sheet fibrils. These findings indicate that cerebrovascular amyloid can serve as an effective scaffold to promote rapid assembly and strong deposition of Aβ into a unique structure that likely contributes to its distinctive pathology. PMID:27869115

Unraveling the key to the resistance of canids to prion diseases

PubMed Central

Fernández-Borges, Natalia; Sánchez-Martín, Manuel A.; Pumarola, Martí

2017-01-01

One of the characteristics of prions is their ability to infect some species but not others and prion resistant species have been of special interest because of their potential in deciphering the determinants for susceptibility. Previously, we developed different in vitro and in vivo models to assess the susceptibility of species that were erroneously considered resistant to prion infection, such as members of the Leporidae and Equidae families. Here we undertake in vitro and in vivo approaches to understand the unresolved low prion susceptibility of canids. Studies based on the amino acid sequence of the canine prion protein (PrP), together with a structural analysis in silico, identified unique key amino acids whose characteristics could orchestrate its high resistance to prion disease. Cell- and brain-based PMCA studies were performed highlighting the relevance of the D163 amino acid in proneness to protein misfolding. This was also investigated by the generation of a novel transgenic mouse model carrying this substitution and these mice showed complete resistance to disease despite intracerebral challenge with three different mouse prion strains (RML, 22L and 301C) known to cause disease in wild-type mice. These findings suggest that dog D163 amino acid is primarily, if not totally, responsible for the prion resistance of canids. PMID:29131852

Imaging colon cancer development in mice: IL-6 deficiency prevents adenoma in azoxymethane-treated Smad3 knockouts

NASA Astrophysics Data System (ADS)

Harpel, Kaitlin; Leung, Sarah; Faith Rice, Photini; Jones, Mykella; Barton, Jennifer K.; Bommireddy, Ramireddy

2016-02-01

The development of colorectal cancer in the azoxymethane-induced mouse model can be observed by using a miniaturized optical coherence tomography (OCT) imaging system. This system is uniquely capable of tracking disease development over time, allowing for the monitoring of morphological changes in the distal colon due to tumor development and the presence of lymphoid aggregates. By using genetically engineered mouse models deficient in Interleukin 6 (IL-6) and Smad family member 3 (Smad3), the role of inflammation on tumor development and the immune system can be elucidated. Smad3 knockout mice develop inflammatory response, wasting, and colitis associated cancer while deficiency of proinflammatory cytokine IL-6 confers resistance to tumorigenesis. We present pilot data showing that the Smad3 knockout group had the highest tumor burden, highest spleen weight, and lowest thymus weight. The IL-6 deficiency in Smad3 knockout mice prevented tumor development, splenomegaly, and thymic atrophy. This finding suggests that agents that inhibit IL-6 (e.g. anti-IL-6 antibody, non-steroidal anti-inflammatory drugs [NSAIDs], etc.) could be used as novel therapeutic agents to prevent disease progression and increase the efficacy of anti-cancer agents. OCT can also be useful for initiating early therapy and assessing the benefit of combination therapy targeting inflammation.

Increased airway reactivity in a neonatal mouse model of Continuous Positive Airway Pressure (CPAP)

PubMed Central

Mayer, Catherine A.; Martin, Richard J.; MacFarlane, Peter M.

2015-01-01

Background Continuous positive airway pressure (CPAP) is a primary form of respiratory support used in the intensive care of preterm infants, but its long-term effects on airway (AW) function are unknown. Methods We developed a neonatal mouse model of CPAP treatment to determine whether it modifies later AW reactivity. Un-anesthetized spontaneously breathing mice were fitted with a mask to deliver CPAP (6cmH2O, 3hrs/day) for 7 consecutive days starting at postnatal day 1. Airway reactivity to methacholine was assessed using the in vitro living lung slice preparation. Results One week of CPAP increased AW responsiveness to methacholine in male, but not female mice, compared to untreated control animals. The AW hyper-reactivity of male mice persisted for 2 weeks (at P21) after CPAP treatment ended. 4 days of CPAP, however, did not significantly increase AW reactivity. Females also exhibited AW hyper-reactivity at P21, suggesting a delayed response to early (7 days) CPAP treatment. The effects of 7 days of CPAP on hyper-reactivity to methacholine were unique to smaller AWs whereas larger ones were relatively unaffected. Conclusion These data may be important to our understanding of the potential long-term consequences of neonatal CPAP therapy used in the intensive care of preterm infants. PMID:25950451

Signaling hierarchy regulating human endothelial cell development

USDA-ARS?s Scientific Manuscript database

Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these stud...

Optimizing mouse models of neurodegenerative disorders: are therapeutics in sight?

PubMed

Lutz, Cathleen M; Osborne, Melissa A

2013-01-01

The genomic and biologic conservation between mice and humans, along with our increasing ability to manipulate the mouse genome, places the mouse as a premier model for deciphering disease mechanisms and testing potential new therapies. Despite these advantages, mouse models of neurodegenerative disease are sometimes difficult to generate and can present challenges that must be carefully addressed when used for preclinical studies. For those models that do exist, the standardization and optimization of the models is a critical step in ensuring success in both basic research and preclinical use. This review looks back on the history of model development for neurodegenerative diseases and highlights the key strategies that have been learned in order to improve the design, development and use of mouse models in the study of neurodegenerative disease.

Habituation, discrimination and anxiety in transgenic mice overexpressing acetylcholinesterase splice variants.

PubMed

Kofman, Ora; Shavit, Yehoshua; Ashkenazi, Sarit; Gabay, Shai

2007-12-14

TgS and TgR transgenic mice overexpress different splice variants of acetylcholinesterase and serve as models for genetic disruption of the cholinergic system. Whereas the TgS mouse overexpresses synaptic AChE, the TgR mouse overexpresses the rare readthrough variant whose C-terminal lacks the cysteine residue which permits adherence to the membrane. The two genotypes were compared to the parent strain, FVB/N mice on locomotion, discrimination learning and anxiety behavior following two exposures to the elevated plus maze. Male TgS mice were slower to acquire a simple odor discrimination, failed to habituate to a novel environment but were not impaired on reversal or set shifting compared to the FVB/N or TgR mice. In addition, TgS mice showed less avoidance behavior on the first exposure and but less exploration on the second exposure to the EPM. TgR mice were not impaired on discrimination learning; however, the females showed excessive running in circles in the activity meter. The findings suggest that the effects of overexpression of AChE are unique to different splice variants and may be sex-dependent.

Chromosome-wise dissection of the genome of the extremely big mouse line DU6i.

PubMed

Bevova, Marianna R; Aulchenko, Yurii S; Aksu, Soner; Renne, Ulla; Brockmann, Gudrun A

2006-01-01

The extreme high-body-weight-selected mouse line DU6i is a polygenic model for growth research, harboring many small-effect QTL. We dissected the genome of this line into 19 autosomes and the Y chromosome by the construction of a new panel of chromosome substitution strains (CSS). The DU6i chromosomes were transferred to a DBA/2 mice genetic background by marker-assisted recurrent backcrossing. Mitochondria and the X chromosome were of DBA/2 origin in the backcross. During the construction of these novel strains, >4000 animals were generated, phenotyped, and genotyped. Using these data, we studied the genetic control of variation in body weight and weight gain at 21, 42, and 63 days. The unique data set facilitated the analysis of chromosomal interaction with sex and parent-of-origin effects. All analyzed chromosomes affected body weight and weight gain either directly or in interaction with sex or parent of origin. The effects were age specific, with some chromosomes showing opposite effects at different stages of development.

Early structural and functional plasticity alterations in a susceptibility period of DYT1 dystonia mouse striatum.

PubMed

Maltese, Marta; Stanic, Jennifer; Tassone, Annalisa; Sciamanna, Giuseppe; Ponterio, Giulia; Vanni, Valentina; Martella, Giuseppina; Imbriani, Paola; Bonsi, Paola; Mercuri, Nicola Biagio; Gardoni, Fabrizio; Pisani, Antonio

2018-03-05

The onset of abnormal movements in DYT1 dystonia is between childhood and adolescence, although it is unclear why clinical manifestations appear during this developmental period. Plasticity at corticostriatal synapses is critically involved in motor memory. In the Tor1a +/Δgag DYT1 dystonia mouse model, long-term potentiation (LTP) appeared prematurely in a critical developmental window in striatal spiny neurons (SPNs), while long-term depression (LTD) was never recorded. Analysis of dendritic spines showed an increase of both spine width and mature mushroom spines in Tor1a +/Δgag neurons, paralleled by an enhanced AMPA receptor (AMPAR) accumulation. BDNF regulates AMPAR expression during development. Accordingly, both proBDNF and BDNF levels were significantly higher in Tor1a +/Δgag mice. Consistently, antagonism of BDNF rescued synaptic plasticity deficits and AMPA currents. Our findings demonstrate that early loss of functional and structural synaptic homeostasis represents a unique endophenotypic trait during striatal maturation, promoting the appearance of clinical manifestations in mutation carriers. © 2018, Maltese et al.

The structure of mouse cytomegalovirus m04 protein obtained from sparse NMR data reveals a conserved fold of the m02-m06 viral immune modulator family.

PubMed

Sgourakis, Nikolaos G; Natarajan, Kannan; Ying, Jinfa; Vogeli, Beat; Boyd, Lisa F; Margulies, David H; Bax, Ad

2014-09-02

Immunoevasins are key proteins used by viruses to subvert host immune responses. Determining their high-resolution structures is key to understanding virus-host interactions toward the design of vaccines and other antiviral therapies. Mouse cytomegalovirus encodes a unique set of immunoevasins, the m02-m06 family, that modulates major histocompatibility complex class I (MHC-I) antigen presentation to CD8+ T cells and natural killer cells. Notwithstanding the large number of genetic and functional studies, the structural biology of immunoevasins remains incompletely understood, largely because of crystallization bottlenecks. Here we implement a technology using sparse nuclear magnetic resonance data and integrative Rosetta modeling to determine the structure of the m04/gp34 immunoevasin extracellular domain. The structure reveals a β fold that is representative of the m02-m06 family of viral proteins, several of which are known to bind MHC-I molecules and interfere with antigen presentation, suggesting its role as a diversified immune regulation module. Copyright © 2014 Elsevier Ltd. All rights reserved.

Applications and Limitations of Mouse Models for Understanding Human Atherosclerosis

PubMed Central

von Scheidt, Moritz; Zhao, Yuqi; Kurt, Zeyneb; Pan, Calvin; Zeng, Lingyao; Yang, Xia; Schunkert, Heribert; Lusis, Aldons J.

2017-01-01

Most of the biological understanding of mechanisms underlying coronary artery disease (CAD) derives from studies of mouse models. The identification of multiple CAD loci and strong candidate genes in large human genome-wide association studies (GWAS) presented an opportunity to examine the relevance of mouse models for the human disease. We comprehensively reviewed the mouse literature, including 827 literature-derived genes, and compared it to human data. First, we observed striking concordance of risk factors for atherosclerosis in mice and humans. Second, there was highly significant overlap of mouse genes with human genes identified by GWAS. In particular, of the 46 genes with strong association signals in CAD-GWAS that were studied in mouse models all but one exhibited consistent effects on atherosclerosis-related phenotypes. Third, we compared 178 CAD-associated pathways derived from human GWAS with 263 from mouse studies and observed that over 50% were consistent between both species. PMID:27916529

A single nucleotide mutation in Nppc is associated with a long bone abnormality in lbab mice.

PubMed

Jiao, Yan; Yan, Jian; Jiao, Feng; Yang, Hongbin; Donahue, Leah Rae; Li, Xinmin; Roe, Bruce A; Stuart, John; Gu, Weikuan

2007-04-17

The long bone abnormality (lbab) mouse is a new autosomal recessive mutant characterized by overall smaller body size with proportionate dwarfing of all organs and shorter long bones. Previous linkage analysis has located the lbab mutation on chromosome 1 between the markers D1Mit9 and D1Mit488. A genome-based positional approach was used to identify a mutation associated with lbab disease. A total of 122 genes and expressed sequence tags at the lbab region were screened for possible mutation by using genomic DNA from lbabl/lbab, lbab/+, and +/+ B6 mice and high throughput temperature gradient capillary electrophoresis. A sequence difference was identified in one of the amplicons of gene Nppc between lbab/lbab and +/+ mice. One-step reverse transcriptase polymerase chain reaction was performed to validate the difference of Nppc in different types of mice at the mRNA level. The mutation of Nppc was unique in lbab/lbab mice among multiple mouse inbred strains. The mutation of Nppc is co-segregated with lbab disease in 200 progenies produced from heterozygous lbab/+ parents. A single nucleotide mutation of Nppc is associated with dwarfism in lbab/lbab mice. Current genome information and technology allow us to efficiently identify single nucleotide mutations from roughly mapped disease loci. The lbab mouse is a useful model for hereditary human achondroplasia.

A single nucleotide mutation in Nppc is associated with a long bone abnormality in lbab mice

PubMed Central

Jiao, Yan; Yan, Jian; Jiao, Feng; Yang, HongBin; Donahue, Leah Rae; Li, Xinmin; Roe, Bruce A; Stuart, John; Gu, Weikuan

2007-01-01

Background The long bone abnormality (lbab) mouse is a new autosomal recessive mutant characterized by overall smaller body size with proportionate dwarfing of all organs and shorter long bones. Previous linkage analysis has located the lbab mutation on chromosome 1 between the markers D1Mit9 and D1Mit488. Results A genome-based positional approach was used to identify a mutation associated with lbab disease. A total of 122 genes and expressed sequence tags at the lbab region were screened for possible mutation by using genomic DNA from lbabl/lbab, lbab/+, and +/+ B6 mice and high throughput temperature gradient capillary electrophoresis. A sequence difference was identified in one of the amplicons of gene Nppc between lbab/lbab and +/+ mice. One-step reverse transcriptase polymerase chain reaction was performed to validate the difference of Nppc in different types of mice at the mRNA level. The mutation of Nppc was unique in lbab/lbab mice among multiple mouse inbred strains. The mutation of Nppc is co-segregated with lbab disease in 200 progenies produced from heterozygous lbab/+ parents. Conclusion A single nucleotide mutation of Nppc is associated with dwarfism in lbab/lbab mice. Current genome information and technology allow us to efficiently identify single nucleotide mutations from roughly mapped disease loci. The lbab mouse is a useful model for hereditary human achondroplasia. PMID:17439653

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.

The latest animal models of ovarian cancer for novel drug discovery.

PubMed

Magnotti, Elizabeth; Marasco, Wayne A

2018-03-01

Epithelial ovarian cancer is a heterogeneous disease classified into five subtypes, each with a different molecular profile. Most cases of ovarian cancer are diagnosed after metastasis of the primary tumor and are resistant to traditional platinum-based chemotherapeutics. Mouse models of ovarian cancer have been utilized to discern ovarian cancer tumorigenesis and the tumor's response to therapeutics. Areas covered: The authors provide a review of mouse models currently employed to understand ovarian cancer. This article focuses on advances in the development of orthotopic and patient-derived tumor xenograft (PDX) mouse models of ovarian cancer and discusses current humanized mouse models of ovarian cancer. Expert opinion: The authors suggest that humanized mouse models of ovarian cancer will provide new insight into the role of the human immune system in combating and augmenting ovarian cancer and aid in the development of novel therapeutics. Development of humanized mouse models will take advantage of the NSG and NSG-SGM3 strains of mice as well as new strains that are actively being derived.

How Genetically Engineered Mouse Tumor Models Provide Insights Into Human Cancers

PubMed Central

Politi, Katerina; Pao, William

2011-01-01

Genetically engineered mouse models (GEMMs) of human cancer were first created nearly 30 years ago. These early transgenic models demonstrated that mouse cells could be transformed in vivo by expression of an oncogene. A new field emerged, dedicated to generating and using mouse models of human cancer to address a wide variety of questions in cancer biology. The aim of this review is to highlight the contributions of mouse models to the diagnosis and treatment of human cancers. Because of the breadth of the topic, we have selected representative examples of how GEMMs are clinically relevant rather than provided an exhaustive list of experiments. Today, as detailed here, sophisticated mouse models are being created to study many aspects of cancer biology, including but not limited to mechanisms of sensitivity and resistance to drug treatment, oncogene cooperation, early detection, and metastasis. Alternatives to GEMMs, such as chemically induced or spontaneous tumor models, are not discussed in this review. PMID:21263096

Integrating model behavior, optimization, and sensitivity/uncertainty analysis: overview and application of the MOUSE software toolbox

USDA-ARS?s Scientific Manuscript database

This paper provides an overview of the Model Optimization, Uncertainty, and SEnsitivity Analysis (MOUSE) software application, an open-source, Java-based toolbox of visual and numerical analysis components for the evaluation of environmental models. MOUSE is based on the OPTAS model calibration syst...

Disrupting the male germ line to find infertility and contraception targets.

PubMed

Archambeault, Denise R; Matzuk, Martin M

2014-05-01

Genetically-manipulated mouse models have become indispensible for broadening our understanding of genes and pathways related to male germ cell development. Until suitable in vitro systems for studying spermatogenesis are perfected, in vivo models will remain the gold standard for inquiry into testicular function. Here, we discuss exciting advances that are allowing researchers faster, easier, and more customizable access to their mouse models of interest. Specifically, the trans-NIH Knockout Mouse Project (KOMP) is working to generate knockout mouse models of every gene in the mouse genome. The related Knockout Mouse Phenotyping Program (KOMP2) is performing systematic phenotypic analysis of this genome-wide collection of knockout mice, including fertility screening. Together, these programs will not only uncover new genes involved in male germ cell development but also provide the research community with the mouse models necessary for further investigations. In addition to KOMP/KOMP2, another promising development in the field of mouse models is the advent of CRISPR (clustered regularly interspaced short palindromic repeat)-Cas technology. Utilizing 20 nucleotide guide sequences, CRISPR/Cas has the potential to introduce sequence-specific insertions, deletions, and point mutations to produce null, conditional, activated, or reporter-tagged alleles. CRISPR/Cas can also successfully target multiple genes in a single experimental step, forgoing the multiple generations of breeding traditionally required to produce mouse models with deletions, insertions, or mutations in multiple genes. In addition, CRISPR/Cas can be used to create mouse models carrying variants identical to those identified in infertile human patients, providing the opportunity to explore the effects of such mutations in an in vivo system. Both the KOMP/KOMP2 projects and the CRISPR/Cas system provide powerful, accessible genetic approaches to the study of male germ cell development in the mouse. A more complete understanding of male germ cell biology is critical for the identification of novel targets for potential non-hormonal contraceptive intervention. Copyright © 2014. Published by Elsevier Masson SAS.

A novel combinational approach of microstimulation and bioluminescence imaging to study the mechanisms of action of cerebral electrical stimulation in mice

PubMed Central

Arsenault, Dany; Drouin-Ouellet, Janelle; Saint-Pierre, Martine; Petrou, Petros; Dubois, Marilyn; Kriz, Jasna; Barker, Roger A; Cicchetti, Antonio; Cicchetti, Francesca

2015-01-01

Key points We have developed a unique prototype to perform brain stimulation in mice. This system presents a number of advantages and new developments: 1) all stimulation parameters can be adjusted, 2) both positive and negative current pulses can be generated, guaranteeing electrically balanced stimulation regimen, 3) which can be produced with both low and high impedance electrodes, 4) the developed electrodes ensure localized stimulation and 5) can be used to stimulate and/or record brain potential and 6) in vivo recording of electric pulses allows the detection of defective electrodes (wire breakage or short circuits). This new micro-stimulator device further allows simultaneous live bioluminescence imaging of the mouse brain, enabling real time assessment of the impact of stimulation on cerebral tissue. The use of this novel tool in various transgenic mouse models of disease opens up a whole new range of possibilities in better understanding brain stimulation. Abstract Deep brain stimulation (DBS) is used to treat a number of neurological conditions and is currently being tested to intervene in neuropsychiatric conditions. However, a better understanding of how it works would ensure that side effects could be minimized and benefits optimized. We have thus developed a unique device to perform brain stimulation (BS) in mice and to address fundamental issues related to this methodology in the pre-clinical setting. This new microstimulator prototype was specifically designed to allow simultaneous live bioluminescence imaging of the mouse brain, allowing real time assessment of the impact of stimulation on cerebral tissue. We validated the authenticity of this tool in vivo by analysing the expression of toll-like receptor 2 (TLR2), corresponding to the microglial response, in the stimulated brain regions of TLR2-fluc-GFP transgenic mice, which we further corroborated with post-mortem analyses in these animals as well as in human brains of patients who underwent DBS to treat their Parkinson's disease. In the present study, we report on the development of the first BS device that allows for simultaneous live in vivo imaging in mice. This tool opens up a whole new range of possibilities that allow a better understanding of BS and how to optimize its effects through its use in murine models of disease. PMID:25653107

Genome-Wide Expression Profiling of Five Mouse Models Identifies Similarities and Differences with Human Psoriasis

PubMed Central

Swindell, William R.; Johnston, Andrew; Carbajal, Steve; Han, Gangwen; Wohn, Christian; Lu, Jun; Xing, Xianying; Nair, Rajan P.; Voorhees, John J.; Elder, James T.; Wang, Xiao-Jing; Sano, Shigetoshi; Prens, Errol P.; DiGiovanni, John; Pittelkow, Mark R.; Ward, Nicole L.; Gudjonsson, Johann E.

2011-01-01

Development of a suitable mouse model would facilitate the investigation of pathomechanisms underlying human psoriasis and would also assist in development of therapeutic treatments. However, while many psoriasis mouse models have been proposed, no single model recapitulates all features of the human disease, and standardized validation criteria for psoriasis mouse models have not been widely applied. In this study, whole-genome transcriptional profiling is used to compare gene expression patterns manifested by human psoriatic skin lesions with those that occur in five psoriasis mouse models (K5-Tie2, imiquimod, K14-AREG, K5-Stat3C and K5-TGFbeta1). While the cutaneous gene expression profiles associated with each mouse phenotype exhibited statistically significant similarity to the expression profile of psoriasis in humans, each model displayed distinctive sets of similarities and differences in comparison to human psoriasis. For all five models, correspondence to the human disease was strong with respect to genes involved in epidermal development and keratinization. Immune and inflammation-associated gene expression, in contrast, was more variable between models as compared to the human disease. These findings support the value of all five models as research tools, each with identifiable areas of convergence to and divergence from the human disease. Additionally, the approach used in this paper provides an objective and quantitative method for evaluation of proposed mouse models of psoriasis, which can be strategically applied in future studies to score strengths of mouse phenotypes relative to specific aspects of human psoriasis. PMID:21483750

Validation and implementation of a novel high-throughput behavioral phenotyping instrument for mice

PubMed Central

Brodkin, Jesse; Frank, Dana; Grippo, Ryan; Hausfater, Michal; Gulinello, Maria; Achterholt, Nils; Gutzen, Christian

2015-01-01

Background Behavioral assessment of mutant mouse models and novel candidate drugs is a slow and labor intensive process. This limitation produces a significant impediment to CNS drug discovery. New method By combining video and vibration analysis we created an automated system that provides the most detailed description of mouse behavior available. Our system (The Behavioral Spectrometer) allowed for the rapid assessment of behavioral abnormalities in the BTBR model of Autism, the restraint model of stress and the irritant model of inflammatory pain. Results We found that each model produced a unique alteration of the spectrum of behavior emitted by the mice. BTBR mice engaged in more grooming and less rearing behaviors. Prior restraint stress produced dramatic increases in grooming activity at the expense of locomotor behavior. Pain produced profound decreases in emitted behavior that were reversible with analgesic treatment. Comparison with existing method(s) We evaluated our system through a direct comparison on the same subjects with the current “gold standard” of human observation of video recordings. Using the same mice evaluated over the same range of behaviors, the Behavioral Spectrometer produced a quantitative categorization of behavior that was highly correlated with the scores produced by trained human observers (r=0.97). Conclusions Our results show that this new system is a highly valid and sensitive method to characterize behavioral effects in mice. As a fully automated and easily scalable instrument the Behavioral Spectrometer represents a high-throughput behavioral tool that reduces the time and labor involved in behavioral research. PMID:24384067

Synthesis, in vitro and in vivo antimalarial assessment of sulfide, sulfone and vinyl amide-substituted 1,2,4-trioxanes prepared via thiol-olefin co-oxygenation (TOCO) of allylic alcohols.

PubMed

Amewu, Richard; Gibbons, Peter; Mukhtar, Amira; Stachulski, Andrew V; Ward, Stephen A; Hall, Charlotte; Rimmer, Karen; Davies, Jill; Vivas, Livia; Bacsa, John; Mercer, Amy E; Nixon, Gemma; Stocks, Paul A; O'Neill, Paul M

2010-05-07

Thiol-Olefin Co-Oxygenation (TOCO) methodology has been applied to the synthesis of a small library of weak base and polar 1,2,4-trioxanes. The 1,2,4-trioxane units synthesised exhibit remarkable stability as they survive base catalysed hydrolysis and mixed anhydride/amine coupling reactions. This unique stability feature has enabled a range of novel substitution patterns to be incorporated within the spiro 1,2,4-trioxane unit. Selected analogues express potent in vitro nM antimalarial activity, low cytotoxicity and oral activity in the Plasmodium berghei mouse model of malaria.

[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.

Generation of transgenic mouse model using PTTG as an oncogene.

PubMed

Kakar, Sham S; Kakar, Cohin

2015-01-01

The close physiological similarity between the mouse and human has provided tools to understanding the biological function of particular genes in vivo by introduction or deletion of a gene of interest. Using a mouse as a model has provided a wealth of resources, knowledge, and technology, helping scientists to understand the biological functions, translocation, trafficking, and interaction of a candidate gene with other intracellular molecules, transcriptional regulation, posttranslational modification, and discovery of novel signaling pathways for a particular gene. Most importantly, the generation of the mouse model for a specific human disease has provided a powerful tool to understand the etiology of a disease and discovery of novel therapeutics. This chapter describes in detail the step-by-step generation of the transgenic mouse model, which can be helpful in guiding new investigators in developing successful models. For practical purposes, we will describe the generation of a mouse model using pituitary tumor transforming gene (PTTG) as the candidate gene of interest.

The Cysteine Dioxgenase Knockout Mouse: Altered Cysteine Metabolism in Nonhepatic Tissues Leads to Excess H2S/HS− Production and Evidence of Pancreatic and Lung Toxicity

PubMed Central

Roman, Heather B.; Hirschberger, Lawrence L.; Krijt, Jakub; Valli, Alessandro; Kožich, Viktor

2013-01-01

Abstract Aims: To define the consequences of loss of cysteine dioxygenase (CDO) on cysteine metabolism at the tissue level, we determined levels of relevant metabolites and enzymes and evidence of H2S/HS− (gaseous hydrogen sulfide and its conjugate base) toxicity in liver, pancreas, kidney, and lung of CDO−/− mice that were fed either a taurine-free or taurine-supplemented diet. Results: CDO−/− mice had low tissue and serum taurine and hypotaurine levels and high tissue levels of cysteine, consistent with the loss of CDO. CDO−/− mice had elevated urinary excretion of thiosulfate, high tissue and serum cystathionine and lanthionine levels, and evidence of inhibition and destabilization of cytochrome c oxidase, which is consistent with excess production of H2S/HS−. Accumulation of cystathionine and lanthionine appeared to result from cystathionine β-synthase (CBS)-mediated cysteine desulfhydration. Very high levels of hypotaurine in pancreas of wild-type mice and very high levels of cystathionine and lanthionine in pancreas of CDO−/− mice were observed, suggesting a unique cysteine metabolism in the pancreas. Innovation: The CDO−/− mouse model provides new insights into tissue-specific cysteine metabolism, particularly the role of pancreas in metabolism of excess cysteine by CBS-catalyzed reactions, and will be a useful model for studying the effects of excess endogenous production of H2S/HS−. Conclusion: The CDO−/− mouse clearly demonstrates that H2S/HS− production in tissues can exceed the capacity of the animal to oxidize sulfide to sulfate and demonstrates that pancreas and lung are more susceptible to toxicity from endogenous H2S/HS−production than are liver and kidney. Antioxid. Redox Signal. 19, 1321–1336. PMID:23350603

Performing label-fusion-based segmentation using multiple automatically generated templates.

PubMed

Chakravarty, M Mallar; Steadman, Patrick; van Eede, Matthijs C; Calcott, Rebecca D; Gu, Victoria; Shaw, Philip; Raznahan, Armin; Collins, D Louis; Lerch, Jason P

2013-10-01

Classically, model-based segmentation procedures match magnetic resonance imaging (MRI) volumes to an expertly labeled atlas using nonlinear registration. The accuracy of these techniques are limited due to atlas biases, misregistration, and resampling error. Multi-atlas-based approaches are used as a remedy and involve matching each subject to a number of manually labeled templates. This approach yields numerous independent segmentations that are fused using a voxel-by-voxel label-voting procedure. In this article, we demonstrate how the multi-atlas approach can be extended to work with input atlases that are unique and extremely time consuming to construct by generating a library of multiple automatically generated templates of different brains (MAGeT Brain). We demonstrate the efficacy of our method for the mouse and human using two different nonlinear registration algorithms (ANIMAL and ANTs). The input atlases consist a high-resolution mouse brain atlas and an atlas of the human basal ganglia and thalamus derived from serial histological data. MAGeT Brain segmentation improves the identification of the mouse anterior commissure (mean Dice Kappa values (κ = 0.801), but may be encountering a ceiling effect for hippocampal segmentations. Applying MAGeT Brain to human subcortical structures improves segmentation accuracy for all structures compared to regular model-based techniques (κ = 0.845, 0.752, and 0.861 for the striatum, globus pallidus, and thalamus, respectively). Experiments performed with three manually derived input templates suggest that MAGeT Brain can approach or exceed the accuracy of multi-atlas label-fusion segmentation (κ = 0.894, 0.815, and 0.895 for the striatum, globus pallidus, and thalamus, respectively). Copyright © 2012 Wiley Periodicals, Inc.

Disruption of bbe02 by Insertion of a Luciferase Gene Increases Transformation Efficiency of Borrelia burgdorferi and Allows Live Imaging in Lyme Disease Susceptible C3H Mice

PubMed Central

Chan, Kamfai; Alter, Laura; Barthold, Stephen W.; Parveen, Nikhat

2015-01-01

Lyme disease is the most prevalent tick-borne disease in North America and Europe. The causative agent, Borrelia burgdorferi persists in the white-footed mouse. Infection with B. burgdorferi can cause acute to persistent multisystemic Lyme disease in humans. Some disease manifestations are also exhibited in the mouse model of Lyme disease. Genetic manipulation of B. burgdorferi remains difficult. First, B. burgdorferi contains a large number of endogenous plasmids with unique sequences encoding unknown functions. The presence of these plasmids needs to be confirmed after each genetic manipulation. Second, the restriction modification defense systems, including that encoded by bbe02 gene lead to low transformation efficiency in B. burgdorferi. Therefore, studying the molecular basis of Lyme pathogenesis is a challenge. Furthermore, investigation of the role of a specific B. burgdorferi protein throughout infection requires a large number of mice, making it labor intensive and expensive. To overcome the problems associated with low transformation efficiency and to reduce the number of mice needed for experiments, we disrupted the bbe02 gene of a highly infectious and pathogenic B. burgdorferi strain, N40 D10/E9 through insertion of a firefly luciferase gene. The bbe02 mutant shows higher transformation efficiency and maintains luciferase activity throughout infection as detected by live imaging of mice. Infectivity and pathogenesis of this mutant were comparable to the wild-type N40 strain. This mutant will serve as an ideal parental strain to examine the roles of various B. burgdorferi proteins in Lyme pathogenesis in the mouse model in the future. PMID:26069970

The murine ufo receptor: molecular cloning, chromosomal localization and in situ expression analysis.

PubMed

Faust, M; Ebensperger, C; Schulz, A S; Schleithoff, L; Hameister, H; Bartram, C R; Janssen, J W

1992-07-01

We have cloned the mouse homologue of the ufo oncogene. It encodes a novel tyrosine kinase receptor characterized by a unique extracellular domain containing two immunoglobulin-like and two fibronectin type III repeats. Comparison of the predicted ufo amino acid sequences of mouse and man revealed an overall identity of 87.6%. The ufo locus maps to mouse chromosome 7A3-B1 and thereby extends the known conserved linkage group between mouse chromosome 7 and human chromosome 19. RNA in situ hybridization analysis established the onset of specific ufo expression in the late embryogenesis at day 12.5 post coitum (p.c.) and localized ufo transcription to distinct substructures of a broad spectrum of developing tissues (e.g. subepidermal cells of the skin, mesenchymal cells of the periosteum). In adult animals ufo is expressed in cells forming organ capsules as well as in connective tissue structures. ufo may function as a signal transducer between specific cell types of mesodermal origin.

Using the Textpresso Site-Specific Recombinases Web server to identify Cre expressing mouse strains and floxed alleles.

PubMed

Condie, Brian G; Urbanski, William M

2014-01-01

Effective tools for searching the biomedical literature are essential for identifying reagents or mouse strains as well as for effective experimental design and informed interpretation of experimental results. We have built the Textpresso Site Specific Recombinases (Textpresso SSR) Web server to enable researchers who use mice to perform in-depth searches of a rapidly growing and complex part of the mouse literature. Our Textpresso Web server provides an interface for searching the full text of most of the peer-reviewed publications that report the characterization or use of mouse strains that express Cre or Flp recombinase. The database also contains most of the publications that describe the characterization or analysis of strains carrying conditional alleles or transgenes that can be inactivated or activated by site-specific recombinases such as Cre or Flp. Textpresso SSR complements the existing online databases that catalog Cre and Flp expression patterns by providing a unique online interface for the in-depth text mining of the site specific recombinase literature.

In vitro transcription of a cloned mouse ribosomal RNA gene.

PubMed Central

Mishima, Y; Yamamoto, O; Kominami, R; Muramatsu, M

1981-01-01

An in vitro transcription system which utilizes cloned mouse ribosomal RNA gene (rDNA) fragments and a mouse cell extract has been developed. RNA polymerases I is apparently responsible for this transcription as evidenced by the complete resistance to a high concentration (200 micrograms/ml) of alpha-amanitin. Run-off products obtained with three different truncated rDNA fragments indicated that RNA was transcribed from a unique site of rDNA. The S1 nuclease protection mapping of the in vitro product and of in vivo 45S RNA confirmed this site, indicating that, in this in vitro system, transcription of rDNA started from the same site as in vivo. This site is located at several hundred nucleotides upstream from the putative initiation site reported by us (1) and by others (2). Some sequence homology surrounding this region was noted among mouse, Xenopus laevis and Drosophila melanogaster. The data also suggest that some processing of the primary transcript occurs in this in vitro system. Images PMID:6278446

Ferret and Pig Models of Cystic Fibrosis: Prospects and Promise for Gene Therapy

PubMed Central

Yan, Ziying; Stewart, Zoe A.; Sinn, Patrick L.; Olsen, John C.; Hu, Jim; McCray, Paul B.

2015-01-01

Abstract Large animal models of genetic diseases are rapidly becoming integral to biomedical research as technologies to manipulate the mammalian genome improve. The creation of cystic fibrosis (CF) ferrets and pigs is an example of such progress in animal modeling, with the disease phenotypes in the ferret and pig models more reflective of human CF disease than mouse models. The ferret and pig CF models also provide unique opportunities to develop and assess the effectiveness of gene and cell therapies to treat affected organs. In this review, we examine the organ disease phenotypes in these new CF models and the opportunities to test gene therapies at various stages of disease progression in affected organs. We then discuss the progress in developing recombinant replication-defective adenoviral, adeno-associated viral, and lentiviral vectors to target genes to the lung and pancreas in ferrets and pigs, the two most affected organs in CF. Through this review, we hope to convey the potential of these new animal models for developing CF gene and cell therapies. PMID:25675143

What Is the Predictive Value of Animal Models for Vaccine Efficacy in Humans? Reevaluating the Potential of Mouse Models for the Human Immune System.

PubMed

Jameson, Stephen C; Masopust, David

2018-04-02

Much of what we understand about immunology, including the response to vaccines, come from studies in mice because they provide many practical advantages compared with research in higher mammals and humans. Nevertheless, modalities for preventing or treating disease do not always translate from mouse to humans, which has led to increasing scrutiny of the continued merits of mouse research. Here, we summarize the pros and cons of current laboratory mouse models for immunology research and discuss whether overreliance on nonphysiological, ultra-hygienic animal husbandry approaches has limited the ultimate translation potential of mouse-derived data to humans. Alternative approaches are discussed that may extend the use of the mouse model for preclinical studies. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

Solvent effects on differentiation of mouse brain tissue using laser microdissection ‘cut and drop’ sampling with direct mass spectral analysis

DOE PAGES

Cahill, John F.; Kertesz, Vilmos; Porta, Tiffany; ...

2018-02-08

Rationale: Laser microdissection-liquid vortex capture/electrospray ionization mass spectrometry (LMD-LVC/ESI-MS) has potential for on-line classification of tissue but an investigation into what analytical conditions provide best spectral differentiation has not been conducted. The effects of solvent, ionization polarity, and spectral acquisition parameters on differentiation of mouse brain tissue regions are described.Methods: Individual 40 × 40 μm microdissections from cortex, white, grey, granular, and nucleus regions of mouse brain tissue were analyzed using different capture/ESI solvents, in positive and negative ion mode ESI, using time-of-flight (TOF)-MS and sequential window acquisitions of all theoretical spectra (SWATH)-MS (a permutation of tandem-MS), and combinations thereof.more » Principal component analysis-linear discriminant analysis (PCA-LDA), applied to each mass spectral dataset, was used to determine the accuracy of differentiation of mouse brain tissue regions. Results: Mass spectral differences associated with capture/ESI solvent composition manifested as altered relative distributions of ions rather than the presence or absence of unique ions. In negative ion mode ESI, 80/20 (v/v) methanol/water yielded spectra with low signal/noise ratios relative to other solvents. PCA-LDA models acquired using 90/10 (v/v) methanol/chloroform differentiated tissue regions with 100% accuracy while data collected using methanol misclassified some samples. The combination of SWATH-MS and TOF-MS data improved differentiation accuracy.Conclusions: Combined TOF-MS and SWATH-MS data differentiated white, grey, granular, and nucleus mouse tissue regions with greater accuracy than when solely using TOF-MS data. Using 90/10 (v/v) methanol/chloroform, tissue regions were perfectly differentiated. Lastly, these results will guide future studies looking to utilize the potential of LMD-LVC/ESI-MS for tissue and disease differentiation.« less

Solvent effects on differentiation of mouse brain tissue using laser microdissection ‘cut and drop’ sampling with direct mass spectral analysis

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

Cahill, John F.; Kertesz, Vilmos; Porta, Tiffany

Rationale: Laser microdissection-liquid vortex capture/electrospray ionization mass spectrometry (LMD-LVC/ESI-MS) has potential for on-line classification of tissue but an investigation into what analytical conditions provide best spectral differentiation has not been conducted. The effects of solvent, ionization polarity, and spectral acquisition parameters on differentiation of mouse brain tissue regions are described.Methods: Individual 40 × 40 μm microdissections from cortex, white, grey, granular, and nucleus regions of mouse brain tissue were analyzed using different capture/ESI solvents, in positive and negative ion mode ESI, using time-of-flight (TOF)-MS and sequential window acquisitions of all theoretical spectra (SWATH)-MS (a permutation of tandem-MS), and combinations thereof.more » Principal component analysis-linear discriminant analysis (PCA-LDA), applied to each mass spectral dataset, was used to determine the accuracy of differentiation of mouse brain tissue regions. Results: Mass spectral differences associated with capture/ESI solvent composition manifested as altered relative distributions of ions rather than the presence or absence of unique ions. In negative ion mode ESI, 80/20 (v/v) methanol/water yielded spectra with low signal/noise ratios relative to other solvents. PCA-LDA models acquired using 90/10 (v/v) methanol/chloroform differentiated tissue regions with 100% accuracy while data collected using methanol misclassified some samples. The combination of SWATH-MS and TOF-MS data improved differentiation accuracy.Conclusions: Combined TOF-MS and SWATH-MS data differentiated white, grey, granular, and nucleus mouse tissue regions with greater accuracy than when solely using TOF-MS data. Using 90/10 (v/v) methanol/chloroform, tissue regions were perfectly differentiated. Lastly, these results will guide future studies looking to utilize the potential of LMD-LVC/ESI-MS for tissue and disease differentiation.« less

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

Scoville, David K.; White, Collin C.; Botta, Dianne

Quantum dots (QDs) are engineered semiconductor nanoparticles with unique physicochemical properties that make them potentially useful in clinical, research and industrial settings. However, a growing body of evidence indicates that like other engineered nanomaterials, QDs have the potential to be respiratory hazards, especially in the context of the manufacture of QDs and products containing them, as well as exposures to consumers using these products. The overall goal of this study was to investigate the role of mouse strain in determining susceptibility to QD-induced pulmonary inflammation and toxicity. Male mice from 8 genetically diverse inbred strains (the Collaborative Cross founder strains)more » were exposed to CdSe–ZnS core–shell QDs stabilized with an amphiphilic polymer. QD treatment resulted in significant increases in the percentage of neutrophils and levels of cytokines present in bronchoalveolar lavage fluid (BALF) obtained from NOD/ShiLtJ and NZO/HlLtJ mice relative to their saline (Sal) treated controls. Cadmium measurements in lung tissue indicated strain-dependent differences in disposition of QDs in the lung. Total glutathione levels in lung tissue were significantly correlated with percent neutrophils in BALF as well as with lung tissue Cd levels. Our findings indicate that QD-induced acute lung inflammation is mouse strain dependent, that it is heritable, and that the choice of mouse strain is an important consideration in planning QD toxicity studies. These data also suggest that formal genetic analyses using additional strains or recombinant inbred strains from these mice could be useful for discovering potential QD-induced inflammation susceptibility loci. - Highlights: • Quantum dot acute lung inflammation was evaluated in a multi-strain mouse model. • QD disposition differed across 8 Collaborative Cross (CC) founder strains. • Neutrophil and cytokine levels in BALF were also mouse strain dependent. • NOD/ShiLtJ, NZO/HlLtJ, and A/J were more sensitive to QDs than C57BL/6J mice. • The cytokines KC and Mip1α were strongly correlated with Cd and BALF neutrophils.« less

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.

Reward-Related Behavioral Paradigms for Addiction Research in the Mouse: Performance of Common Inbred Strains

PubMed Central

Feyder, Michael; Brigman, Jonathan L.; Crombag, Hans S.; Saksida, Lisa M.; Bussey, Timothy J.; Holmes, Andrew

2011-01-01

The mouse has emerged as a uniquely valuable species for studying the molecular and genetic basis of complex behaviors and modeling neuropsychiatric disease states. While valid and reliable preclinical assays for reward-related behaviors are critical to understanding addiction-related processes, and various behavioral procedures have been developed and characterized in rats and primates, there have been relatively few studies using operant-based addiction-relevant behavioral paradigms in the mouse. Here we describe the performance of the C57BL/6J inbred mouse strain on three major reward-related paradigms, and replicate the same procedures in two other commonly used inbred strains (DBA/2J, BALB/cJ). We examined Pavlovian-instrumental transfer (PIT) by measuring the ability of an auditory cue associated with food reward to promote an instrumental (lever press) response. In a separate experiment, we assessed the acquisition and extinction of a simple stimulus-reward instrumental behavior on a touchscreen-based task. Reinstatement of this behavior was then examined following either continuous exposure to cues (conditioned reinforcers, CRs) associated with reward, brief reward and CR exposure, or brief reward exposure followed by continuous CR exposure. The third paradigm examined sensitivity of an instrumental (lever press) response to devaluation of food reward (a probe for outcome insensitive, habitual behavior) by repeated pairing with malaise. Results showed that C57BL/6J mice displayed robust PIT, as well as clear extinction and reinstatement, but were insensitive to reinforcer devaluation. DBA/2J mice showed good PIT and (rewarded) reinstatement, but were slow to extinguish and did not show reinforcer devaluation or significant CR-reinstatement. BALB/cJ mice also displayed good PIT, extinction and reinstatement, and retained instrumental responding following devaluation, but, unlike the other strains, demonstrated reduced Pavlovian approach behavior (food magazine head entries). Overall, these assays provide robust paradigms for future studies using the mouse to elucidate the neural, molecular and genetic factors underpinning reward-related behaviors relevant to addiction research. PMID:21249214

Reward-related behavioral paradigms for addiction research in the mouse: performance of common inbred strains.

PubMed

Lederle, Lauren; Weber, Susanna; Wright, Tara; Feyder, Michael; Brigman, Jonathan L; Crombag, Hans S; Saksida, Lisa M; Bussey, Timothy J; Holmes, Andrew

2011-01-10

The mouse has emerged as a uniquely valuable species for studying the molecular and genetic basis of complex behaviors and modeling neuropsychiatric disease states. While valid and reliable preclinical assays for reward-related behaviors are critical to understanding addiction-related processes, and various behavioral procedures have been developed and characterized in rats and primates, there have been relatively few studies using operant-based addiction-relevant behavioral paradigms in the mouse. Here we describe the performance of the C57BL/6J inbred mouse strain on three major reward-related paradigms, and replicate the same procedures in two other commonly used inbred strains (DBA/2J, BALB/cJ). We examined Pavlovian-instrumental transfer (PIT) by measuring the ability of an auditory cue associated with food reward to promote an instrumental (lever press) response. In a separate experiment, we assessed the acquisition and extinction of a simple stimulus-reward instrumental behavior on a touch screen based task. Reinstatement of this behavior was then examined following either continuous exposure to cues (conditioned reinforcers, CRs) associated with reward, brief reward and CR exposure, or brief reward exposure followed by continuous CR exposure. The third paradigm examined sensitivity of an instrumental (lever press) response to devaluation of food reward (a probe for outcome insensitive, habitual behavior) by repeated pairing with malaise. Results showed that C57BL/6J mice displayed robust PIT, as well as clear extinction and reinstatement, but were insensitive to reinforcer devaluation. DBA/2J mice showed good PIT and (rewarded) reinstatement, but were slow to extinguish and did not show reinforcer devaluation or significant CR-reinstatement. BALB/cJ mice also displayed good PIT, extinction and reinstatement, and retained instrumental responding following devaluation, but, unlike the other strains, demonstrated reduced Pavlovian approach behavior (food magazine head entries). Overall, these assays provide robust paradigms for future studies using the mouse to elucidate the neural, molecular and genetic factors underpinning reward-related behaviors relevant to addiction research.

Mouse Models in Bone Marrow Transplantation and Adoptive Cellular Therapy

PubMed Central

Arber, Caroline; Brenner, Malcolm K.; Reddy, Pavan

2014-01-01

Mouse models of transplantation have been indispensable to the development of bone marrow transplantation (BMT). Their role in the generation of basic science knowledge is invaluable and is subject to discussion below. However, this article focuses on the direct role and relevance of mouse models towards the clinical development and advances in BMT and adoptive T-cell therapy for human diseases. The authors aim to present a thoughtful perspective on the pros and cons of mouse models while noting that despite imperfections these models are obligatory for the development of science-based medicine. PMID:24216170

PREGNANCY LOSS ASSOCIATED WITH EXPOSURE TO PERFLUOROOCTANOIC ACID IN THE MOUSE

EPA Science Inventory

Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acids that have unique surfactant properties and are widely used in industrial and consumer products. These chemicals are stable and persistent in the environment; recent bio-monitoring studies have indicated wide-sp...

The structure and organization of lanceolate mechanosensory complexes at mouse hair follicles

PubMed Central

Li, Lishi; Ginty, David D

2014-01-01

In mouse hairy skin, lanceolate complexes associated with three types of hair follicles, guard, awl/auchene and zigzag, serve as mechanosensory end organs. These structures are formed by unique combinations of low-threshold mechanoreceptors (LTMRs), Aβ RA-LTMRs, Aδ-LTMRs, and C-LTMRs, and their associated terminal Schwann cells (TSCs). In this study, we investigated the organization, ultrastructure, and maintenance of longitudinal lanceolate complexes at each hair follicle subtype. We found that TSC processes at hair follicles are tiled and that individual TSCs host axonal endings of more than one LTMR subtype. Electron microscopic analyses revealed unique ultrastructural features of lanceolate complexes that are proposed to underlie mechanotransduction. Moreover, Schwann cell ablation leads to loss of LTMR terminals at hair follicles while, in contrast, TSCs remain associated with hair follicles following skin denervation in adult mice and, remarkably, become re-associated with newly formed axons, indicating a TSC-dependence of lanceolate complex maintenance and regeneration in adults. DOI: http://dx.doi.org/10.7554/eLife.01901.001 PMID:24569481

The structure and organization of lanceolate mechanosensory complexes at mouse hair follicles.

PubMed

Li, Lishi; Ginty, David D

2014-02-25

In mouse hairy skin, lanceolate complexes associated with three types of hair follicles, guard, awl/auchene and zigzag, serve as mechanosensory end organs. These structures are formed by unique combinations of low-threshold mechanoreceptors (LTMRs), Aβ RA-LTMRs, Aδ-LTMRs, and C-LTMRs, and their associated terminal Schwann cells (TSCs). In this study, we investigated the organization, ultrastructure, and maintenance of longitudinal lanceolate complexes at each hair follicle subtype. We found that TSC processes at hair follicles are tiled and that individual TSCs host axonal endings of more than one LTMR subtype. Electron microscopic analyses revealed unique ultrastructural features of lanceolate complexes that are proposed to underlie mechanotransduction. Moreover, Schwann cell ablation leads to loss of LTMR terminals at hair follicles while, in contrast, TSCs remain associated with hair follicles following skin denervation in adult mice and, remarkably, become re-associated with newly formed axons, indicating a TSC-dependence of lanceolate complex maintenance and regeneration in adults. DOI: http://dx.doi.org/10.7554/eLife.01901.001.

Transcriptional architecture of the primate neocortex.

PubMed

Bernard, Amy; Lubbers, Laura S; Tanis, Keith Q; Luo, Rui; Podtelezhnikov, Alexei A; Finney, Eva M; McWhorter, Mollie M E; Serikawa, Kyle; Lemon, Tracy; Morgan, Rebecca; Copeland, Catherine; Smith, Kimberly; Cullen, Vivian; Davis-Turak, Jeremy; Lee, Chang-Kyu; Sunkin, Susan M; Loboda, Andrey P; Levine, David M; Stone, David J; Hawrylycz, Michael J; Roberts, Christopher J; Jones, Allan R; Geschwind, Daniel H; Lein, Ed S

2012-03-22

Genome-wide transcriptional profiling was used to characterize the molecular underpinnings of neocortical organization in rhesus macaque, including cortical areal specialization and laminar cell-type diversity. Microarray analysis of individual cortical layers across sensorimotor and association cortices identified robust and specific molecular signatures for individual cortical layers and areas, prominently involving genes associated with specialized neuronal function. Overall, transcriptome-based relationships were related to spatial proximity, being strongest between neighboring cortical areas and between proximal layers. Primary visual cortex (V1) displayed the most distinctive gene expression compared to other cortical regions in rhesus and human, both in the specialized layer 4 as well as other layers. Laminar patterns were more similar between macaque and human compared to mouse, as was the unique V1 profile that was not observed in mouse. These data provide a unique resource detailing neocortical transcription patterns in a nonhuman primate with great similarity in gene expression to human. Copyright © 2012 Elsevier Inc. All rights reserved.

Centralized mouse repositories.

PubMed

Donahue, Leah Rae; Hrabe de Angelis, Martin; Hagn, Michael; Franklin, Craig; Lloyd, K C Kent; Magnuson, Terry; McKerlie, Colin; Nakagata, Naomi; Obata, Yuichi; Read, Stuart; Wurst, Wolfgang; Hörlein, Andreas; Davisson, Muriel T

2012-10-01

Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world.

Centralized Mouse Repositories

PubMed Central

Donahue, Leah Rae; de Angelis, Martin Hrabe; Hagn, Michael; Franklin, Craig; Lloyd, K. C. Kent; Magnuson, Terry; McKerlie, Colin; Nakagata, Naomi; Obata, Yuichi; Read, Stuart; Wurst, Wolfgang; Hörlein, Andreas; Davisson, Muriel T.

2013-01-01

Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world. PMID:22945696

Peripheral administration of antisense oligonucleotides targeting the amyloid-β protein precursor reverses AβPP and LRP-1 overexpression in the aged SAMP8 mouse brain.

PubMed

Erickson, Michelle A; Niehoff, Michael L; Farr, Susan A; Morley, John E; Dillman, Lucy A; Lynch, Kristin M; Banks, William A

2012-01-01

The senescence accelerated mouse-prone 8 (SAMP8) mouse model of Alzheimer's disease has a natural mutation leading to age-related increases in the amyloid-β protein precursor (AβPP) and amyloid-β (Aβ) in the brain, memory impairment, and deficits in Aβ removal from the brain. Previous studies show that centrally administered antisense oligonucleotide directed against AβPP can decrease AβPP expression and Aβ production in the brains of aged SAMP8 mice, and improve memory. The same antisense crosses the blood-brain barrier and reverses memory deficits when injected intravenously. Here, we give 6 μg of AβPP or control antisense 3 times over 2 week intervals to 12 month old SAMP8 mice. Object recognition test was done 48 hours later, followed by removal of whole brains for immunoblot analysis of AβPP, low-density lipoprotein-related protein-1 (LRP-1), p-glycoprotein (Pgp), receptor for advanced glycation endproducts (RAGE), or ELISA of soluble Aβ(40). Our results show that AβPP antisense completely reverses a 30% age-associated increase in AβPP signal (p < 0.05 versus untreated 4 month old SAMP8). Soluble Aβ(40) increased with age, but was not reversed by antisense. LRP-1 large and small subunits increased significantly with age (147.7%, p < 0.01 and 123.7%, p < 0.05 respectively), and AβPP antisense completely reversed these increases (p < 0.05). Pgp and RAGE were not significantly altered with age or antisense. Antisense also caused improvements in memory (p < 0.001). Together, these data support the therapeutic potential of AβPP antisense and show a unique association between AβPP and LRP-1 expression in the SAMP8 mouse.

Fundamental characteristics of the expressed immunoglobulin VH and VL repertoire in different canine breeds in comparison with those of humans and mice.

PubMed

Steiniger, Sebastian C J; Dunkle, William E; Bammert, Gary F; Wilson, Thomas L; Krishnan, Abhiram; Dunham, Steven A; Ippolito, Gregory C; Bainbridge, Graeme

2014-05-01

Complementarity determining regions (CDR) are responsible for binding antigen and provide substantial diversity to the antibody repertoire, with VH CDR3 of the immunoglobulin variable heavy (VH) domain playing a dominant role. In this study, we examined 1200 unique canine VH and 500 unique variable light (VL) sequences of large and small canine breeds derived from peripheral B cells. Unlike the human and murine repertoire, the canine repertoire is heavily dominated by the Canis lupus familiaris IGHV1 subgroup, evolutionarily closest to the human IGHV3 subgroup. Our studies clearly show that the productive canine repertoire of all analyzed breeds shows similarities to both human and mouse; however, there are distinct differences in terms of VH CDR3 length and amino acid paratope composition. In comparison with the human and murine antibody repertoire, canine VH CDR3 regions are shorter in length than the human counterparts, but longer than the murine VH CDR3. Similar to corresponding human and mouse VH CDR3, the amino acids at the base of the VH CDR3 loop are strictly conserved. For identical CDR positions, there were significant changes in chemical paratope composition. Similar to human and mouse repertoires, the neutral amino acids tyrosine, glycine and serine dominate the canine VH CDR3 interval (comprising 35%) although the interval is nonetheless relatively depleted of tyrosine when compared to human and mouse. Furthermore, canine VH CDR3 displays an overrepresentation of the neutral amino acid threonine and the negatively charged aspartic acid while proline content is similar to that in the human repertoire. In general, the canine repertoire shows a bias towards small, negatively charged amino acids. Overall, this analysis suggests that functional canine therapeutic antibodies can be obtained from human and mouse sequences by methods of speciation and affinity maturation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Molecular Indicators of Stress-Induced Neuroinflammation in a Mouse Model Simulating Features of Post-Traumatic Stress Disorder (Open Access)

DTIC Science & Technology

2017-05-23

OPEN ORIGINAL ARTICLE Molecular indicators of stress-induced neuroinflammation in a mouse model simulating features of post -traumatic stress disorder... post -traumatic stress disorder (PTSD). The model involved exposure of an intruder (male C57BL/6) mouse to a resident aggressor (male SJL) mouse for 5...revealed that neurogenesis and synaptic plasticity pathways were activated during the early responses but were inhibited after the later post -trauma

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

Kishigami, Satoshi; Kinki University, 930 Nishimitani, Kinokawa 599-5993; Wakayama, Sayaka

In mammals, a diploid genome of an individual following fertilization of an egg and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual ending. Even as cultured cells from the individual, they cannot normally proliferate in perpetuity because of the 'Hayflick limit'. However, Dolly, the sheep cloned from an adult mammary gland cell, changes this scenario. Somatic cell nuclear transfer (SCNT) enables us to produce offspring without germ cells, that is, to 'passage' a unique diploid genome. Animal cloning has also proven to be a powerful research tool for reprogrammingmore » in many mammals, notably mouse and cow. The mechanism underlying reprogramming, however, remains largely unknown and, animal cloning has been inefficient as a result. More momentously, in addition to abortion and fetal mortality, some cloned animals display possible premature aging phenotypes including early death and short telomere lengths. Under these inauspicious conditions, is it really possible for SCNT to preserve a diploid genome? Delightfully, in mouse and recently in primate, using SCNT we can produce nuclear transfer ES cells (ntES) more efficiently, which can preserve the eternal lifespan for the 'passage' of a unique diploid genome. Further, new somatic cloning technique using histone-deacetylase inhibitors has been developed which can significantly increase the previous cloning rates two to six times. Here, we introduce SCNT and its value as a preservation tool for a diploid genome while reviewing aging of cloned animals on cellular and individual levels.« less

Intracerebral Inoculation of Mouse-Passaged Saffold Virus Type 3 Affects Cerebellar Development in Neonatal Mice

PubMed Central

Kotani, Osamu; Suzuki, Tadaki; Yokoyama, Masaru; Iwata-Yoshikawa, Naoko; Nakajima, Noriko; Sato, Hironori; Hasegawa, Hideki; Taguchi, Fumihiro; Shimizu, Hiroyuki

2016-01-01

ABSTRACT Saffold virus (SAFV), a human cardiovirus, is occasionally detected in infants with neurological disorders, including meningitis and cerebellitis. We recently reported that SAFV type 3 isolates infect cerebellar glial cells, but not large neurons, in mice. However, the impact of this infection remained unclear. Here, we determined the neuropathogenesis of SAFV type 3 in the cerebella of neonatal ddY mice by using SAFV passaged in the cerebella of neonatal BALB/c mice. The virus titer in the cerebellum increased following the inoculation of each of five passaged strains. The fifth passaged strain harbored amino acid substitutions in the VP2 (H160R and Q239R) and VP3 (K62M) capsid proteins. Molecular modeling of the capsid proteins suggested that the VP2-H160R and VP3-K62M mutations alter the structural dynamics of the receptor binding surface via the formation of a novel hydrophobic interaction between the VP2 puff B and VP3 knob regions. Compared with the original strain, the passaged strain showed altered growth characteristics in human-derived astroglial cell lines and greater replication in the brains of neonatal mice. In addition, the passaged strain was more neurovirulent than the original strain, while both strains infected astroglial and neural progenitor cells in the mouse brain. Intracerebral inoculation of either the original or the passaged strain affected brain Purkinje cell dendrites, and a high titer of the passaged strain induced cerebellar hypoplasia in neonatal mice. Thus, infection by mouse-passaged SAFV affected cerebellar development in neonatal mice. This animal model contributes to the understanding of the neuropathogenicity of SAFV infections in infants. IMPORTANCE Saffold virus (SAFV) is a candidate neuropathogenic agent in infants and children, but the neuropathogenicity of the virus has not been fully elucidated. Recently, we evaluated the pathogenicity of two clinical SAFV isolates in mice. Similar to other neurotropic picornaviruses, these isolates showed mild infectivity of glial and neural progenitor cells, but not of large neurons, in the cerebellum. However, the outcome of this viral infection in the cerebellum has not been clarified. Here, we examined the tropism of SAFV in the cerebellum. We obtained an in vivo-passaged strain from the cerebella of neonatal mice and examined its genome and its neurovirulence in the neonatal mouse brain. The passaged virus showed high infectivity and neurovirulence in the brain, especially the cerebellum, and affected cerebellar development. This unique neonatal mouse model will be helpful for elucidating the neuropathogenesis of SAFV infections occurring early in life. PMID:27581974

Genetic characterization and improved genotyping of the dysferlin-deficient mouse strain Dysf (tm1Kcam).

PubMed

Wiktorowicz, Tatiana; Kinter, Jochen; Kobuke, Kazuhiro; Campbell, Kevin P; Sinnreich, Michael

2015-01-01

Mouse models of dysferlinopathies are valuable tools with which to investigate the pathomechanisms underlying these diseases and to test novel therapeutic strategies. One such mouse model is the Dysf (tm1Kcam) strain, which was generated using a targeting vector to replace a 12-kb region of the dysferlin gene and which features a progressive muscular dystrophy. A prerequisite for successful animal studies using genetic mouse models is an accurate genotyping protocol. Unfortunately, the lack of robustness of currently available genotyping protocols for the Dysf (tm1Kcam) mouse has prevented efficient colony management. Initial attempts to improve the genotyping protocol based on the published genomic structure failed. These difficulties led us to analyze the targeted locus of the dysferlin gene of the Dysf (tm1Kcam) mouse in greater detail. In this study we resequenced and analyzed the targeted locus of the Dysf (tm1Kcam) mouse and developed a novel PCR protocol for genotyping. We found that instead of a deletion, the dysferlin locus in the Dysf (tm1Kcam) mouse carries a targeted insertion. This genetic characterization enabled us to establish a reliable method for genotyping of the Dysf (tm1Kcam) mouse, and thus has made efficient colony management possible. Our work will make the Dysf (tm1Kcam) mouse model more attractive for animal studies of dysferlinopathies.

Mouse models of neurodegenerative diseases: criteria and general methodology.

PubMed

Janus, Christopher; Welzl, Hans

2010-01-01

The major symptom of Alzheimer's disease is rapidly progressing dementia, coinciding with the formation of amyloid and tau deposits in the central nervous system, and neuronal death. At present familial cases of dementias provide the most promising foundation for modelling neurodegeneration. We describe the mnemonic and other major behavioral symptoms of tauopathies, briefly outline the genetics underlying familiar cases and discuss the arising implications for modelling the disease in mostly transgenic mouse lines. We then depict to what degree the most recent mouse models replicate pathological and cognitive characteristics observed in patients.There is no universally valid behavioral test battery to evaluate mouse models. The selection of individual tests depends on the behavioral and/or memory system in focus, the type of a model and how well it replicates the pathology of a disease and the amount of control over the genetic background of the mouse model. However it is possible to provide guidelines and criteria for modelling the neurodegeneration, setting up the experiments and choosing relevant tests. One should not adopt a "one (trans)gene, one disease" interpretation, but should try to understand how the mouse genome copes with the protein expression of the transgene in question. Further, it is not possible to recommend some mouse models over others since each model is valuable within its own constraints, and the way experiments are performed often reflects the idiosyncratic reality of specific laboratories. Our purpose is to improve bridging molecular and behavioural approaches in translational research.

Direct comparison of the pharmacodynamics of four antifungal drugs in a mouse model of disseminated candidiasis using microbiological assays of serum drug concentrations.

PubMed

Maki, Katsuyuki; Holmes, Ann R; Watabe, Etsuko; Iguchi, Yumi; Matsumoto, Satoru; Ikeda, Fumiaki; Tawara, Shuichi; Mutoh, Seitaro

2007-01-01

The aim of this study was to compare the pharmacodynamics of the azole antifungal drugs fluconazole, itraconazole and ketoconazole, and the polyene antifungal amphotericin B, in a mouse model of disseminated Candida albicans infection. In order to directly compare effective serum concentrations of these antifungals, drug concentrations were assayed microbiologically by measuring inhibition of C. albicans mycelial growth (mMIC) in a mouse serum-based assay (serum antifungal titer). Efficacy in the mouse infection model was determined using an organ-based (kidney burden) endpoint. For all four drugs, the serum antifungal titers, 8 hr after administration of single doses of drugs at a range of drug concentrations, correlated closely with C. albicans kidney fungal burden in the mouse model. The results showed that determining serum antifungal titer may be used to accurately represent kidney fungal burden in a mouse model of disseminated candidiasis and allowed direct comparison of the pharmacodynamics of differing classes of antifungal drugs.

Mouse Models as Tools to Identify Genetic Pathways for Retinal Degeneration, as Exemplified by Leber's Congenital Amaurosis.

PubMed

Chang, Bo

2016-01-01

Leber's congenital amaurosis (LCA) is an inherited retinal degenerative disease characterized by severe loss of vision in the first year of life. In addition to early vision loss, a variety of other eye-related abnormalities including roving eye movements, deep-set eyes, and sensitivity to bright light also occur with this disease. Many animal models of LCA are available and the study them has led to a better understanding of the pathology of the disease, and has led to the development of therapeutic strategies aimed at curing or slowing down LCA. Mouse models, with their well-developed genetics and similarity to human physiology and anatomy, serve as powerful tools with which to investigate the etiology of human LCA. Such mice provide reproducible, experimental systems for elucidating pathways of normal development, function, designing strategies and testing compounds for translational research and gene-based therapies aimed at delaying the diseases progression. In this chapter, I describe tools used in the discovery and evaluation of mouse models of LCA including a Phoenix Image-Guided Optical Coherence Tomography (OCT) and a Diagnosys Espion Visual Electrophysiology System. Three mouse models are described, the rd3 mouse model for LCA12 and LCA1, the rd12 mouse model for LCA2, and the rd16 mouse model for LCA10.

Diffusion Kurtosis Imaging Detects Microstructural Alterations in Brain of α-Synuclein Overexpressing Transgenic Mouse Model of Parkinson's Disease: A Pilot Study.

PubMed

Khairnar, Amit; Latta, Peter; Drazanova, Eva; Ruda-Kucerova, Jana; Szabó, Nikoletta; Arab, Anas; Hutter-Paier, Birgit; Havas, Daniel; Windisch, Manfred; Sulcova, Alexandra; Starcuk, Zenon; Rektorova, Irena

2015-11-01

Evidence suggests that accumulation and aggregation of α-synuclein contribute to the pathogenesis of Parkinson's disease (PD). The aim of this study was to evaluate whether diffusion kurtosis imaging (DKI) will provide a sensitive tool for differentiating between α-synuclein-overexpressing transgenic mouse model of PD (TNWT-61) and wild-type (WT) littermates. This experiment was designed as a proof-of-concept study and forms a part of a complex protocol and ongoing translational research. Nine-month-old TNWT-61 mice and age-matched WT littermates underwent behavioral tests to monitor motor impairment and MRI scanning using 9.4 Tesla system in vivo. Tract-based spatial statistics (TBSS) and the DKI protocol were used to compare the whole brain white matter of TNWT-61 and WT mice. In addition, region of interest (ROI) analysis was performed in gray matter regions such as substantia nigra, striatum, hippocampus, sensorimotor cortex, and thalamus known to show higher accumulation of α-synuclein. For the ROI analysis, both DKI (6 b-values) protocol and conventional (2 b-values) diffusion tensor imaging (cDTI) protocol were used. TNWT-61 mice showed significant impairment of motor coordination. With the DKI protocol, mean, axial, and radial kurtosis were found to be significantly elevated, whereas mean and radial diffusivity were decreased in the TNWT-61 group compared to that in the WT controls with both TBSS and ROI analysis. With the cDTI protocol, the ROI analysis showed decrease in all diffusivity parameters in TNWT-61 mice. The current study provides evidence that DKI by providing both kurtosis and diffusivity parameters gives unique information that is complementary to cDTI for in vivo detection of pathological changes that underlie PD-like symptomatology in TNWT-61 mouse model of PD. This result is a crucial step in search for a candidate diagnostic biomarker with translational potential and relevance for human studies.

Enhanced in Vivo Efficacy of a Type I Interferon Superagonist with Extended Plasma Half-life in a Mouse Model of Multiple Sclerosis*

PubMed Central

Harari, Daniel; Kuhn, Nadine; Abramovich, Renne; Sasson, Keren; Zozulya, Alla L.; Smith, Paul; Schlapschy, Martin; Aharoni, Rina; Köster, Mario; Eilam, Raya; Skerra, Arne; Schreiber, Gideon

2014-01-01

IFNβ is a common therapeutic option to treat multiple sclerosis. It is unique among the family of type I IFNs in that it binds to the interferon receptors with high affinity, conferring exceptional biological properties. We have previously reported the generation of an interferon superagonist (dubbed YNSα8) that is built on the backbone of a low affinity IFNα but modified to exhibit higher receptor affinity than even for IFNβ. Here, YNSα8 was fused with a 600-residue hydrophilic, unstructured N-terminal polypeptide chain comprising proline, alanine, and serine (PAS) to prolong its plasma half-life via “PASylation.” PAS-YNSα8 exhibited a 10-fold increased half-life in both pharmacodynamic and pharmacokinetic assays in a transgenic mouse model harboring the human receptors, notably without any detectable loss in biological potency or bioavailability. This long-lived superagonist conferred significantly improved protection from MOG35–55-induced experimental autoimmune encephalomyelitis compared with IFNβ, despite being injected with a 4-fold less frequency and at an overall 16-fold lower dosage. These data were corroborated by FACS measurements showing a decrease of CD11b+/CD45hi myeloid lineage cells detectable in the CNS, as well as a decrease in IBA+ cells in spinal cord sections determined by immunohistochemistry for PAS-YNSα8-treated animals. Importantly, PAS-YNSα8 did not induce antibodies upon repeated administration, and its biological efficacy remained unchanged after 21 days of treatment. A striking correlation between increased levels of CD274 (PD-L1) transcripts from spleen-derived CD4+ cells and improved clinical response to autoimmune encephalomyelitis was observed, indicating that, at least in this mouse model of multiple sclerosis, CD274 may serve as a biomarker to predict the effectiveness of IFN therapy to treat this complex disease. PMID:25193661

An Inducible Transgenic Mouse Model for Immune Mediated Hepatitis Showing Clearance of Antigen Expressing Hepatocytes by CD8+ T Cells

PubMed Central

Cebula, Marcin; Ochel, Aaron; Hillebrand, Upneet; Pils, Marina C.; Schirmbeck, Reinhold; Hauser, Hansjörg; Wirth, Dagmar

2013-01-01

The liver has the ability to prime immune responses against neo antigens provided upon infections. However, T cell immunity in liver is uniquely modulated by the complex tolerogenic property of this organ that has to also cope with foreign agents such as endotoxins or food antigens. In this respect, the nature of intrahepatic T cell responses remains to be fully characterized. To gain deeper insight into the mechanisms that regulate the CD8+ T cell responses in the liver, we established a novel OVA_X_CreERT2 mouse model. Upon tamoxifen administration OVA antigen expression is observed in a fraction of hepatocytes, resulting in a mosaic expression pattern. To elucidate the cross-talk of CD8+ T cells with antigen-expressing hepatocytes, we adoptively transferred Kb/OVA257-264-specific OT-I T cells to OVA_X_CreERT2 mice or generated triple transgenic OVA_X CreERT2_X_OT-I mice. OT-I T cells become activated in OVA_X_CreERT2 mice and induce an acute and transient hepatitis accompanied by liver damage. In OVA_X_CreERT2_X_OT-I mice, OVA induction triggers an OT-I T cell mediated, fulminant hepatitis resulting in 50% mortality. Surviving mice manifest a long lasting hepatitis, and recover after 9 weeks. In these experimental settings, recovery from hepatitis correlates with a complete loss of OVA expression indicating efficient clearance of the antigen-expressing hepatocytes. Moreover, a relapse of hepatitis can be induced upon re-induction of cured OVA_X_CreERT2_X_OT-I mice indicating absence of tolerogenic mechanisms. This pathogen-free, conditional mouse model has the advantage of tamoxifen inducible tissue specific antigen expression that reflects the heterogeneity of viral antigen expression and enables the study of intrahepatic immune responses to both de novo and persistent antigen. It allows following the course of intrahepatic immune responses: initiation, the acute phase and antigen clearance. PMID:23869228

Differences in Pathogenesis for Salmonella enterica serovar Typhimurium in the Mouse Versus the Swine Model Identify Bacterial Gene Products Required for Systemic but not Gastrointestinal Disease

USDA-ARS?s Scientific Manuscript database

Over the last several decades, the mouse model of Typhoid fever has been an extremely productive model to investigate Salmonella enterica serovar Typhimurium pathogenesis. The mouse is the paradigm for investigating systemic disease due to infection by Salmonella; however, the swine model of gastro...

A Stratified Transcriptomics Analysis of Polygenic Fat and Lean Mouse Adipose Tissues Identifies Novel Candidate Obesity Genes

PubMed Central

Morton, Nicholas M.; Nelson, Yvonne B.; Michailidou, Zoi; Di Rollo, Emma M.; Ramage, Lynne; Hadoke, Patrick W. F.; Seckl, Jonathan R.; Bunger, Lutz; Horvat, Simon; Kenyon, Christopher J.; Dunbar, Donald R.

2011-01-01

Background Obesity and metabolic syndrome results from a complex interaction between genetic and environmental factors. In addition to brain-regulated processes, recent genome wide association studies have indicated that genes highly expressed in adipose tissue affect the distribution and function of fat and thus contribute to obesity. Using a stratified transcriptome gene enrichment approach we attempted to identify adipose tissue-specific obesity genes in the unique polygenic Fat (F) mouse strain generated by selective breeding over 60 generations for divergent adiposity from a comparator Lean (L) strain. Results To enrich for adipose tissue obesity genes a ‘snap-shot’ pooled-sample transcriptome comparison of key fat depots and non adipose tissues (muscle, liver, kidney) was performed. Known obesity quantitative trait loci (QTL) information for the model allowed us to further filter genes for increased likelihood of being causal or secondary for obesity. This successfully identified several genes previously linked to obesity (C1qr1, and Np3r) as positional QTL candidate genes elevated specifically in F line adipose tissue. A number of novel obesity candidate genes were also identified (Thbs1, Ppp1r3d, Tmepai, Trp53inp2, Ttc7b, Tuba1a, Fgf13, Fmr) that have inferred roles in fat cell function. Quantitative microarray analysis was then applied to the most phenotypically divergent adipose depot after exaggerating F and L strain differences with chronic high fat feeding which revealed a distinct gene expression profile of line, fat depot and diet-responsive inflammatory, angiogenic and metabolic pathways. Selected candidate genes Npr3 and Thbs1, as well as Gys2, a non-QTL gene that otherwise passed our enrichment criteria were characterised, revealing novel functional effects consistent with a contribution to obesity. Conclusions A focussed candidate gene enrichment strategy in the unique F and L model has identified novel adipose tissue-enriched genes contributing to obesity. PMID:21915269

A stratified transcriptomics analysis of polygenic fat and lean mouse adipose tissues identifies novel candidate obesity genes.

PubMed

Morton, Nicholas M; Nelson, Yvonne B; Michailidou, Zoi; Di Rollo, Emma M; Ramage, Lynne; Hadoke, Patrick W F; Seckl, Jonathan R; Bunger, Lutz; Horvat, Simon; Kenyon, Christopher J; Dunbar, Donald R

2011-01-01

Obesity and metabolic syndrome results from a complex interaction between genetic and environmental factors. In addition to brain-regulated processes, recent genome wide association studies have indicated that genes highly expressed in adipose tissue affect the distribution and function of fat and thus contribute to obesity. Using a stratified transcriptome gene enrichment approach we attempted to identify adipose tissue-specific obesity genes in the unique polygenic Fat (F) mouse strain generated by selective breeding over 60 generations for divergent adiposity from a comparator Lean (L) strain. To enrich for adipose tissue obesity genes a 'snap-shot' pooled-sample transcriptome comparison of key fat depots and non adipose tissues (muscle, liver, kidney) was performed. Known obesity quantitative trait loci (QTL) information for the model allowed us to further filter genes for increased likelihood of being causal or secondary for obesity. This successfully identified several genes previously linked to obesity (C1qr1, and Np3r) as positional QTL candidate genes elevated specifically in F line adipose tissue. A number of novel obesity candidate genes were also identified (Thbs1, Ppp1r3d, Tmepai, Trp53inp2, Ttc7b, Tuba1a, Fgf13, Fmr) that have inferred roles in fat cell function. Quantitative microarray analysis was then applied to the most phenotypically divergent adipose depot after exaggerating F and L strain differences with chronic high fat feeding which revealed a distinct gene expression profile of line, fat depot and diet-responsive inflammatory, angiogenic and metabolic pathways. Selected candidate genes Npr3 and Thbs1, as well as Gys2, a non-QTL gene that otherwise passed our enrichment criteria were characterised, revealing novel functional effects consistent with a contribution to obesity. A focussed candidate gene enrichment strategy in the unique F and L model has identified novel adipose tissue-enriched genes contributing to obesity.

The Gne M712T mouse as a model for human glomerulopathy.

PubMed

Kakani, Sravan; Yardeni, Tal; Poling, Justin; Ciccone, Carla; Niethamer, Terren; Klootwijk, Enriko D; Manoli, Irini; Darvish, Daniel; Hoogstraten-Miller, Shelley; Zerfas, Patricia; Tian, E; Ten Hagen, Kelly G; Kopp, Jeffrey B; Gahl, William A; Huizing, Marjan

2012-04-01

Pathological glomerular hyposialylation has been implicated in certain unexplained glomerulopathies, including minimal change nephrosis, membranous glomerulonephritis, and IgA nephropathy. We studied our previously established mouse model carrying a homozygous mutation in the key enzyme of sialic acid biosynthesis, N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase. Mutant mice died before postnatal day 3 (P3) from severe glomerulopathy with podocyte effacement and segmental glomerular basement membrane splitting due to hyposialylation. Administration of the sialic acid precursor N-acetylmannosamine (ManNAc) led to improved sialylation and survival of mutant pups beyond P3. We determined the onset of the glomerulopathy in the embryonic stage. A lectin panel, distinguishing normally sialylated from hyposialylated glycans, used WGA, SNA, PNA, Jacalin, HPA, and VVA, indicating glomerular hyposialylation of predominantly O-linked glycoproteins in mutant mice. The glomerular glycoproteins nephrin and podocalyxin were hyposialylated in this unique murine model. ManNAc treatment appeared to ameliorate the hyposialylation status of mutant mice, indicated by a lectin histochemistry pattern similar to that of wild-type mice, with improved sialylation of both nephrin and podocalyxin, as well as reduced albuminuria compared with untreated mutant mice. These findings suggest application of our lectin panel for categorizing human kidney specimens based on glomerular sialylation status. Moreover, the partial restoration of glomerular architecture in ManNAc-treated mice highlights ManNAc as a potential treatment for humans affected with disorders of glomerular hyposialylation. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Modulating inflammatory monocytes with a unique microRNA gene signature ameliorates murine ALS.

PubMed

Butovsky, Oleg; Siddiqui, Shafiuddin; Gabriely, Galina; Lanser, Amanda J; Dake, Ben; Murugaiyan, Gopal; Doykan, Camille E; Wu, Pauline M; Gali, Reddy R; Iyer, Lakshmanan K; Lawson, Robert; Berry, James; Krichevsky, Anna M; Cudkowicz, Merit E; Weiner, Howard L

2012-09-01

Amyotrophic lateral sclerosis (ALS) is a progressive disease associated with neuronal cell death that is thought to involve aberrant immune responses. Here we investigated the role of innate immunity in a mouse model of ALS. We found that inflammatory monocytes were activated and that their progressive recruitment to the spinal cord, but not brain, correlated with neuronal loss. We also found a decrease in resident microglia in the spinal cord with disease progression. Prior to disease onset, splenic Ly6Chi monocytes expressed a polarized macrophage phenotype (M1 signature), which included increased levels of chemokine receptor CCR2. As disease onset neared, microglia expressed increased CCL2 and other chemotaxis-associated molecules, which led to the recruitment of monocytes to the CNS by spinal cord-derived microglia. Treatment with anti-Ly6C mAb modulated the Ly6Chi monocyte cytokine profile, reduced monocyte recruitment to the spinal cord, diminished neuronal loss, and extended survival. In humans with ALS, the analogous monocytes (CD14+CD16-) exhibited an ALS-specific microRNA inflammatory signature similar to that observed in the ALS mouse model, linking the animal model and the human disease. Thus, the profile of monocytes in ALS patients may serve as a biomarker for disease stage or progression. Our results suggest that recruitment of inflammatory monocytes plays an important role in disease progression and that modulation of these cells is a potential therapeutic approach.

Targeting acetylcholine receptor M3 prevents the progression of airway hyperreactivity in a mouse model of childhood asthma.

PubMed

Patel, Kruti R; Bai, Yan; Trieu, Kenneth G; Barrios, Juliana; Ai, Xingbin

2017-10-01

Asthma often progresses into adulthood from early-life episodes of adverse environmental exposures. However, how the injury to developing lungs contributes to the pathophysiology of persistent asthma remains poorly understood. In this study, we identified an age-related mechanism along the cholinergic nerve-airway smooth muscle (ASM) axis that underlies prolonged airway hyperreactivity (AHR) in mice. We showed that ASM continued to mature until ∼3 wk after birth. Coinciding with postnatal ASM maturation, there was a critical time window for the development of ASM hypercontractility after cholinergic stimulation. We found that allergen exposure in neonatal mice, but not in adult mice, elevated the level and activity of cholinergic nerves (termed neuroplasticity). We demonstrated that cholinergic neuroplasticity is necessary for the induction of persistent AHR after neonatal exposure during rescue assays in mice deficient in neuroplasticity. In addition, early intervention with cholinergic receptor muscarinic (ChRM)-3 blocker reversed the progression of AHR in the neonatal exposure model, whereas β2-adrenoceptor agonists had no such effect. Together, our findings demonstrate a functional relationship between cholinergic neuroplasticity and ASM contractile phenotypes that operates uniquely in early life to induce persistent AHR after allergen exposure. Targeting ChRM3 may have disease-modifying benefits in childhood asthma.-Patel, K. R., Bai, Y., Trieu, K. G., Barrios, J., Ai, X. Targeting acetylcholine receptor M3 prevents the progression of airway hyperreactivity in a mouse model of childhood asthma. © FASEB.

A unified model of the excitability of mouse sensory and motor axons.

PubMed

Makker, Preet G S; Matamala, José Manuel; Park, Susanna B; Lees, Justin G; Kiernan, Matthew C; Burke, David; Moalem-Taylor, Gila; Howells, James

2018-06-19

Non-invasive nerve excitability techniques have provided valuable insight into the understanding of neurological disorders. The widespread use of mice in translational research on peripheral nerve disorders and by pharmaceutical companies during drug development requires valid and reliable models that can be compared to humans. This study established a novel experimental protocol that enables comparative assessment of the excitability properties of motor and sensory axons at the same site in mouse caudal nerve, compared the mouse data to data for motor and sensory axons in human median nerve at the wrist, and constructed a mathematical model of the excitability of mouse axons. In a separate study, ischaemia was employed as an experimental manoeuvre to test the translational utility of this preparation. The patterns of mouse sensory and motor excitability were qualitatively similar to human studies under normal and ischaemic conditions. The most conspicuous differences between mouse and human studies were observed in the recovery cycle and the response to hyperpolarization. Modelling showed that an increase in temperature in mouse axons could account for most of the differences in the recovery cycle. The modelling also suggested a larger hyperpolarization-activated conductance in mouse axons. The kinetics of this conductance appeared to be much slower raising the possibility that an additional or different hyperpolarization-activated cyclic-nucleotide gated (HCN) channel isoform underlies the accommodation to hyperpolarization in mouse axons. Given a possible difference in HCN isoforms, caution should be exercised in extrapolating from studies of mouse motor and sensory axons to human nerve disorders. This article is protected by copyright. All rights reserved.

Rapamycin improves sociability in the BTBR T(+)Itpr3(tf)/J mouse model of autism spectrum disorders.

PubMed

Burket, Jessica A; Benson, Andrew D; Tang, Amy H; Deutsch, Stephen I

2014-01-01

Overactivation of the mammalian target of rapamycin (mTOR) has been implicated in the pathogenesis of syndromic forms of autism spectrum disorders (ASDs), such as tuberous sclerosis complex, neurofibromatosis 1, and fragile X syndrome. Administration of mTORC1 (mTOR complex 1) inhibitors (e.g. rapamycin) in syndromic mouse models of ASDs improved behavior, cognition, and neuropathology. However, since only a minority of ASDs are due to the effects of single genes (∼10%), there is a need to explore inhibition of mTOR activity in mouse models that may be more relevant to the majority of nonsyndromic presentations, such as the genetically inbred BTBR T(+)Itpr3(tf)/J (BTBR) mouse model of ASDs. BTBR mice have social impairment and exhibit increased stereotypic behavior. In prior work, d-cycloserine, a partial glycineB site agonist that targets the N-methyl-d-aspartate (NMDA) receptor, was shown to improve sociability in both Balb/c and BTBR mouse models of ASDs. Importantly, NMDA receptor activation regulates mTOR signaling activity. The current study investigated the ability of rapamycin (10mg/kg, i.p.×four days), an mTORC1 inhibitor, to improve sociability and stereotypic behavior in BTBR mice. Using a standard paradigm to assess mouse social behavior, rapamycin improved several measures of sociability in the BTBR mouse, suggesting that mTOR overactivation represents a therapeutic target that mediates or contributes to impaired sociability in the BTBR mouse model of ASDs. Interestingly, there was no effect of rapamycin on stereotypic behaviors in this mouse model. Copyright © 2013 Elsevier Inc. All rights reserved.

Mediation of mouse natural cytotoxic activity by tumour necrosis factor

NASA Astrophysics Data System (ADS)

Ortaldo, John R.; Mason, Llewellyn H.; Mathieson, Bonnie J.; Liang, Shu-Mei; Flick, David A.; Herberman, Ronald B.

1986-06-01

Natural cell-mediated cytotoxic activity in the mouse has been associated with two types of effector cells, the natural killer (NK) cell and the natural cytotoxic (NC) cell, which seem to differ with regard to their patterns of target selectivity, cell surface characteristics and susceptibility to regulatory factors1. During studies on the mechanism of action of cytotoxic molecules, it became evident that WEHI-164, the prototype NC target cell, was highly susceptible to direct lysis by both human and mouse recombinant tumour necrosis factor (TNF). Here we show that NC, but not NK activity mediated by normal splenocytes, is abrogated by rabbit antibodies to recombinant and natural TNF, respectively. Thus, the cell-mediated activity defined as NC is due to release of TNF by normal spleen cells and does not represent a unique natural effector mechanism.

In Vivo Hyperthermic Stress Model: An Easy Tool to Study the Effects of Oxidative Stress on Neuronal Tau Functionality in Mouse Brain.

PubMed

Chauderlier, Alban; Delattre, Lucie; Buée, Luc; Galas, Marie-Christine

2017-01-01

Oxidative damage is an early event in neurodegenerative disorders such as Alzheimer disease. To increase oxidative stress in AD-related mouse models is essential to study early mechanisms involved in the physiopathology of these diseases. In this chapter, we describe an experimental mouse model of transient and acute hyperthermic stress to induce in vivo an increase of oxidative stress in the brain of any kind of wild-type or transgenic mouse.

Localization of PPAR isotypes in the adult mouse and human brain

PubMed Central

Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B.; Mayfield, R. Dayne; Harris, R. Adron

2016-01-01

Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain. PMID:27283430

Localization of PPAR isotypes in the adult mouse and human brain.

PubMed

Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B; Mayfield, R Dayne; Harris, R Adron

2016-06-10

Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain.

Exploring human disease using the Rat Genome Database.

PubMed

Shimoyama, Mary; Laulederkind, Stanley J F; De Pons, Jeff; Nigam, Rajni; Smith, Jennifer R; Tutaj, Marek; Petri, Victoria; Hayman, G Thomas; Wang, Shur-Jen; Ghiasvand, Omid; Thota, Jyothi; Dwinell, Melinda R

2016-10-01

Rattus norvegicus, the laboratory rat, has been a crucial model for studies of the environmental and genetic factors associated with human diseases for over 150 years. It is the primary model organism for toxicology and pharmacology studies, and has features that make it the model of choice in many complex-disease studies. Since 1999, the Rat Genome Database (RGD; http://rgd.mcw.edu) has been the premier resource for genomic, genetic, phenotype and strain data for the laboratory rat. The primary role of RGD is to curate rat data and validate orthologous relationships with human and mouse genes, and make these data available for incorporation into other major databases such as NCBI, Ensembl and UniProt. RGD also provides official nomenclature for rat genes, quantitative trait loci, strains and genetic markers, as well as unique identifiers. The RGD team adds enormous value to these basic data elements through functional and disease annotations, the analysis and visual presentation of pathways, and the integration of phenotype measurement data for strains used as disease models. Because much of the rat research community focuses on understanding human diseases, RGD provides a number of datasets and software tools that allow users to easily explore and make disease-related connections among these datasets. RGD also provides comprehensive human and mouse data for comparative purposes, illustrating the value of the rat in translational research. This article introduces RGD and its suite of tools and datasets to researchers - within and beyond the rat community - who are particularly interested in leveraging rat-based insights to understand human diseases. © 2016. Published by The Company of Biologists Ltd.

Chronic activation of wild-type epidermal growth factor receptor and loss of Cdkn2a cause mouse glioblastoma formation.

PubMed

Acquaviva, Jaime; Jun, Hyun Jung; Lessard, Julie; Ruiz, Rolando; Zhu, Haihao; Donovan, Melissa; Woolfenden, Steve; Boskovitz, Abraham; Raval, Ami; Bronson, Roderick T; Pfannl, Rolf; Whittaker, Charles A; Housman, David E; Charest, Al

2011-12-01

Glioblastoma multiforme (GBM) is characterized by overexpression of epidermal growth factor receptor (EGFR) and loss of the tumor suppressors Ink4a/Arf. Efforts at modeling GBM using wild-type EGFR in mice have proven unsuccessful. Here, we present a unique mouse model of wild-type EGFR-driven gliomagenesis. We used a combination of somatic conditional overexpression and ligand-mediated chronic activation of EGFR in cooperation with Ink4a/Arf loss in the central nervous system of adult mice to generate tumors with the histopathologic and molecular characteristics of human GBMs. Sustained, ligand-mediated activation of EGFR was necessary for gliomagenesis, functionally substantiating the clinical observation that EGFR-positive GBMs from patients express EGFR ligands. To gain a better understanding of the clinically disappointing EGFR-targeted therapies for GBM, we investigated the molecular responses to EGFR tyrosine kinase inhibitor (TKI) treatment in this model. Gefitinib treatment of primary GBM cells resulted in a robust apoptotic response, partially conveyed by mitogen-activated protein kinase (MAPK) signaling attenuation and accompanied by BIM(EL) expression. In human GBMs, loss-of-function mutations in the tumor suppressor PTEN are a common occurrence. Elimination of PTEN expression in GBM cells posttumor formation did not confer resistance to TKI treatment, showing that PTEN status in our model is not predictive. Together, these findings offer important mechanistic insights into the genetic determinants of EGFR gliomagenesis and sensitivity to TKIs and provide a robust discovery platform to better understand the molecular events that are associated with predictive markers of TKI therapy.

3D visualization and quantification of bone and teeth mineralization for the study of osteo/dentinogenesis in mice models

NASA Astrophysics Data System (ADS)

Marchadier, A.; Vidal, C.; Ordureau, S.; Lédée, R.; Léger, C.; Young, M.; Goldberg, M.

2011-03-01

Research on bone and teeth mineralization in animal models is critical for understanding human pathologies. Genetically modified mice represent highly valuable models for the study of osteo/dentinogenesis defects and osteoporosis. Current investigations on mice dental and skeletal phenotype use destructive and time consuming methods such as histology and scanning microscopy. Micro-CT imaging is quicker and provides high resolution qualitative phenotypic description. However reliable quantification of mineralization processes in mouse bone and teeth are still lacking. We have established novel CT imaging-based software for accurate qualitative and quantitative analysis of mouse mandibular bone and molars. Data were obtained from mandibles of mice lacking the Fibromodulin gene which is involved in mineralization processes. Mandibles were imaged with a micro-CT originally devoted to industrial applications (Viscom, X8060 NDT). 3D advanced visualization was performed using the VoxBox software (UsefulProgress) with ray casting algorithms. Comparison between control and defective mice mandibles was made by applying the same transfer function for each 3D data, thus allowing to detect shape, colour and density discrepencies. The 2D images of transverse slices of mandible and teeth were similar and even more accurate than those obtained with scanning electron microscopy. Image processing of the molars allowed the 3D reconstruction of the pulp chamber, providing a unique tool for the quantitative evaluation of dentinogenesis. This new method is highly powerful for the study of oro-facial mineralizations defects in mice models, complementary and even competitive to current histological and scanning microscopy appoaches.

Genomic variants in an inbred mouse model predict mania-like behaviors.

PubMed

Saul, Michael C; Stevenson, Sharon A; Zhao, Changjiu; Driessen, Terri M; Eisinger, Brian E; Gammie, Stephen C

2018-01-01

Contemporary rodent models for bipolar disorders split the bipolar spectrum into complimentary behavioral endophenotypes representing mania and depression. Widely accepted mania models typically utilize single gene transgenics or pharmacological manipulations, but inbred rodent strains show great potential as mania models. Their acceptance is often limited by the lack of genotypic data needed to establish construct validity. In this study, we used a unique strategy to inexpensively explore and confirm population allele differences in naturally occurring candidate variants in a manic rodent strain, the Madison (MSN) mouse strain. Variants were identified using whole exome resequencing on a small population of animals. Interesting candidate variants were confirmed in a larger population with genotyping. We enriched these results with observations of locomotor behavior from a previous study. Resequencing identified 447 structural variants that are mostly fixed in the MSN strain relative to control strains. After filtering and annotation, we found 11 non-synonymous MSN variants that we believe alter protein function. The allele frequencies for 6 of these variants were consistent with explanatory variants for the Madison strain's phenotype. The variants are in the Npas2, Cp, Polr3c, Smarca4, Trpv1, and Slc5a7 genes, and many of these genes' products are in pathways implicated in human bipolar disorders. Variants in Smarca4 and Polr3c together explained over 40% of the variance in locomotor behavior in the Hsd:ICR founder strain. These results enhance the MSN strain's construct validity and implicate altered nucleosome structure and transcriptional regulation as a chief molecular system underpinning behavior.

Implementation of a manual for working with wobbler mice and criteria for discontinuation of the experiment.

PubMed

Ott, Bastian; Dahlke, Carolin; Meller, Karl; Napirei, Markus; Schmitt-John, Thomas; Brand-Saberi, Beate; Theiss, Carsten; Saberi, Darius

2015-07-01

Mouse breeding is of importance to a whole range of medical and biological research. There are many known mouse models for motor neuron diseases. However, it must be kept in mind that especially mouse models for amyotrophic lateral sclerosis develop severe symptoms causing intense stress. This article is designed to summarize conscientious work with the wobbler mouse, a model for the sporadic form of amyotrophic lateral sclerosis. This mouse model is characterized by a degeneration of α-motor-neurons leading to head tremor, loss of body weight and rapidly progressive paralysis. Although this mouse model has been known since 1956, there are no guidelines for breeding wobbler mice. Due to the lack of such guidelines the present study tries to close this gap and implements a manual for further studies. It includes the whole workflow in regard to wobbler mice from breeding and animal care taking, genotyping and phenotype analysis, but also gives some examples for the use of various neuronal tissues for histological investigation. Beside the progress in research a second aim should always be the enhancement of mouse welfare and reduction of stress for the laboratory animals. Copyright © 2015 Elsevier GmbH. All rights reserved.

Rational Design of Mouse Models for Cancer Research.

PubMed

Landgraf, Marietta; McGovern, Jacqui A; Friedl, Peter; Hutmacher, Dietmar W

2018-03-01

The laboratory mouse is widely considered as a valid and affordable model organism to study human disease. Attempts to improve the relevance of murine models for the investigation of human pathologies led to the development of various genetically engineered, xenograft and humanized mouse models. Nevertheless, most preclinical studies in mice suffer from insufficient predictive value when compared with cancer biology and therapy response of human patients. We propose an innovative strategy to improve the predictive power of preclinical cancer models. Combining (i) genomic, tissue engineering and regenerative medicine approaches for rational design of mouse models with (ii) rapid prototyping and computational benchmarking against human clinical data will enable fast and nonbiased validation of newly generated models. Copyright © 2017 Elsevier Ltd. All rights reserved.

Review of DoD Malaria Research Programs,

DTIC Science & Technology

1992-05-01

the irraliated sporozoite vaccine. Work in the mouse model system and then extrapolate to human malarias. Study naturally acquired immune ...recombinant vaccines. Work simultaneously in the mouse model system and with human malarias. 3. Identify targets and mechanisms of protective immunity not...multivalent vaccines that attack these same targets. 3. Working again in the mouse model, non- human primate model, andI human systems we

α2 Integrin, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-3 act sequentially to induce differentiation of mouse embryonic stem cells into odontoblast-like cells

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

Ozeki, Nobuaki; Kawai, Rie; Hase, Naoko

We previously reported that interleukin 1β acts via matrix metalloproteinase (MMP)-3 to regulate cell proliferation and suppress apoptosis in α2 integrin-positive odontoblast-like cells differentiated from mouse embryonic stem (ES) cells. Here we characterize the signal cascade underpinning odontoblastic differentiation in mouse ES cells. The expression of α2 integrin, extracellular matrix metalloproteinase inducer (Emmprin), and MMP-3 mRNA and protein were all potently increased during odontoblastic differentiation. Small interfering RNA (siRNA) disruption of the expression of these effectors potently suppressed the expression of the odontoblastic biomarkers dentin sialophosphoprotein, dentin matrix protein-1 and alkaline phosphatase, and blocked odontoblast calcification. Our siRNA, western blotmore » and blocking antibody analyses revealed a unique sequential cascade involving α2 integrin, Emmprin and MMP-3 that drives ES cell differentiation into odontoblasts. This cascade requires the interaction between α2 integrin and Emmprin and is potentiated by exogenous MMP-3. Finally, although odontoblast-like cells potently express α2, α6, αV, β1, and β3, integrins, we confirmed that β1 integrin acts as the trigger for ES cell differentiation, apparently in complex with α2 integrin. These results demonstrate a unique and unanticipated role for an α2 integrin-, Emmprin-, and MMP-3-mediated signaling cascade in driving mouse ES cell differentiation into odontoblast-like cells. - Highlights: • Odontoblast differentiation requires activation of α2 integrin, Emmprin and MMP-3. • α2 integrin, Emmprin and MMP-3 form a sequential signaling cascade. • β1 integrin acts a specific trigger for odontoblast differentiation. • The role of these effectors is highly novel and unanticipated.« less

Animal models for prenatal gene therapy: rodent models for prenatal gene therapy.

PubMed

Roybal, Jessica L; Endo, Masayuki; Buckley, Suzanne M K; Herbert, Bronwen R; Waddington, Simon N; Flake, Alan W

2012-01-01

Fetal gene transfer has been studied in various animal models, including rabbits, guinea pigs, cats, dogs, and nonhuman primate; however, the most common model is the rodent, particularly the mouse. There are numerous advantages to mouse models, including a short gestation time of around 20 days, large litter size usually of more than six pups, ease of colony maintenance due to the small physical size, and the relatively low expense of doing so. Moreover, the mouse genome is well defined, there are many transgenic models particularly of human monogenetic disorders, and mouse-specific biological reagents are readily available. One criticism has been that it is difficult to perform procedures on the fetal mouse with suitable accuracy. Over the past decade, accumulation of technical expertise and development of technology such as high-frequency ultrasound have permitted accurate vector delivery to organs and tissues. Here, we describe our experiences of gene transfer to the fetal mouse with and without ultrasound guidance from mid to late gestation. Depending upon the vector type, the route of delivery and the age of the fetus, specific or widespread gene transfer can be achieved, making fetal mice excellent models for exploratory biodistribution studies.

Structural Insights into the Transport Mechanism of the Human Sodium-dependent Lysophosphatidylcholine Transporter MFSD2A*♦

PubMed Central

Quek, Debra Q. Y.; Nguyen, Long N.; Fan, Hao; Silver, David L.

2016-01-01

Major facilitator superfamily domain containing 2A (MFSD2A) was recently characterized as a sodium-dependent lysophosphatidylcholine transporter expressed at the blood-brain barrier endothelium. It is the primary route for importation of docosohexaenoic acid and other long-chain fatty acids into fetal and adult brain and is essential for mouse and human brain growth and function. Remarkably, MFSD2A is the first identified major facilitator superfamily member that uniquely transports lipids, implying that MFSD2A harbors unique structural features and transport mechanism. Here, we present three three-dimensional structural models of human MFSD2A derived by homology modeling using MelB- and LacY-based crystal structures and refined by biochemical analysis. All models revealed 12 transmembrane helices and connecting loops and represented the partially outward-open, outward-partially occluded, and inward-open states of the transport cycle. In addition to a conserved sodium-binding site, three unique structural features were identified as follows: a phosphate headgroup binding site, a hydrophobic cleft to accommodate a hydrophobic hydrocarbon tail, and three sets of ionic locks that stabilize the outward-open conformation. Ligand docking studies and biochemical assays identified Lys-436 as a key residue for transport. It is seen forming a salt bridge with the negative charge on the phosphate headgroup. Importantly, MFSD2A transported structurally related acylcarnitines but not a lysolipid without a negative charge, demonstrating the necessity of a negatively charged headgroup interaction with Lys-436 for transport. These findings support a novel transport mechanism by which lysophosphatidylcholines are “flipped” within the transporter cavity by pivoting about Lys-436 leading to net transport from the outer to the inner leaflet of the plasma membrane. PMID:26945070

Expression profiles of urbilaterian genes uniquely shared between honey bee and vertebrates

PubMed Central

Matsui, Toshiaki; Yamamoto, Toshiyuki; Wyder, Stefan; Zdobnov, Evgeny M; Kadowaki, Tatsuhiko

2009-01-01

Background Large-scale comparison of metazoan genomes has revealed that a significant fraction of genes of the last common ancestor of Bilateria (Urbilateria) is lost in each animal lineage. This event could be one of the underlying mechanisms involved in generating metazoan diversity. However, the present functions of these ancient genes have not been addressed extensively. To understand the functions and evolutionary mechanisms of such ancient Urbilaterian genes, we carried out comprehensive expression profile analysis of genes shared between vertebrates and honey bees but not with the other sequenced ecdysozoan genomes (honey bee-vertebrate specific, HVS genes) as a model. Results We identified 30 honey bee and 55 mouse HVS genes. Many HVS genes exhibited tissue-selective expression patterns; intriguingly, the expression of 60% of honey bee HVS genes was found to be brain enriched, and 24% of mouse HVS genes were highly expressed in either or both the brain and testis. Moreover, a minimum of 38% of mouse HVS genes demonstrated neuron-enriched expression patterns, and 62% of them exhibited expression in selective brain areas, particularly the forebrain and cerebellum. Furthermore, gene ontology (GO) analysis of HVS genes predicted that 35% of genes are associated with DNA transcription and RNA processing. Conclusion These results suggest that HVS genes include genes that are biased towards expression in the brain and gonads. They also demonstrate that at least some of Urbilaterian genes retained in the specific animal lineage may be selectively maintained to support the species-specific phenotypes. PMID:19138430

Expression profiles of urbilaterian genes uniquely shared between honey bee and vertebrates.

PubMed

Matsui, Toshiaki; Yamamoto, Toshiyuki; Wyder, Stefan; Zdobnov, Evgeny M; Kadowaki, Tatsuhiko

2009-01-12

Large-scale comparison of metazoan genomes has revealed that a significant fraction of genes of the last common ancestor of Bilateria (Urbilateria) is lost in each animal lineage. This event could be one of the underlying mechanisms involved in generating metazoan diversity. However, the present functions of these ancient genes have not been addressed extensively. To understand the functions and evolutionary mechanisms of such ancient Urbilaterian genes, we carried out comprehensive expression profile analysis of genes shared between vertebrates and honey bees but not with the other sequenced ecdysozoan genomes (honey bee-vertebrate specific, HVS genes) as a model. We identified 30 honey bee and 55 mouse HVS genes. Many HVS genes exhibited tissue-selective expression patterns; intriguingly, the expression of 60% of honey bee HVS genes was found to be brain enriched, and 24% of mouse HVS genes were highly expressed in either or both the brain and testis. Moreover, a minimum of 38% of mouse HVS genes demonstrated neuron-enriched expression patterns, and 62% of them exhibited expression in selective brain areas, particularly the forebrain and cerebellum. Furthermore, gene ontology (GO) analysis of HVS genes predicted that 35% of genes are associated with DNA transcription and RNA processing. These results suggest that HVS genes include genes that are biased towards expression in the brain and gonads. They also demonstrate that at least some of Urbilaterian genes retained in the specific animal lineage may be selectively maintained to support the species-specific phenotypes.

A novel auditory ossicles membrane and the development of conductive hearing loss in Dmp1-null mice.

PubMed

Lv, Kun; Huang, Haiyang; Yi, Xing; Chertoff, Mark E; Li, Chaoyuan; Yuan, Baozhi; Hinton, Robert J; Feng, Jian Q

2017-10-01

Genetic mouse models are widely used for understanding human diseases but we know much less about the anatomical structure of the auditory ossicles in the mouse than we do about human ossicles. Furthermore, current studies have mainly focused on disease conditions such as osteomalacia and rickets in patients with hypophosphatemia rickets, although the reason that these patients develop late-onset hearing loss is unknown. In this study, we first analyzed Dmp1 lac Z knock-in auditory ossicles (in which the blue reporter is used to trace DMP1 expression in osteocytes) using X-gal staining and discovered a novel bony membrane surrounding the mouse malleus. This finding was further confirmed by 3-D micro-CT, X-ray, and alizarin red stained images. We speculate that this unique structure amplifies and facilitates sound wave transmissions in two ways: increasing the contact surface between the eardrum and malleus and accelerating the sound transmission due to its mineral content. Next, we documented a progressive deterioration in the Dmp1-null auditory ossicle structures using multiple imaging techniques. The auditory brainstem response test demonstrated a conductive hearing loss in the adult Dmp1-null mice. This finding may help to explain in part why patients with DMP1 mutations develop late-onset hearing loss, and supports the critical role of DMP1 in maintaining the integrity of the auditory ossicles and its bony membrane. Copyright © 2017 Elsevier Inc. All rights reserved.

Voltage-sensitive rhodol with enhanced two-photon brightness.

PubMed

Kulkarni, Rishikesh U; Kramer, Daniel J; Pourmandi, Narges; Karbasi, Kaveh; Bateup, Helen S; Miller, Evan W

2017-03-14

We have designed, synthesized, and applied a rhodol-based chromophore to a molecular wire-based platform for voltage sensing to achieve fast, sensitive, and bright voltage sensing using two-photon (2P) illumination. Rhodol VoltageFluor-5 (RVF5) is a voltage-sensitive dye with improved 2P cross-section for use in thick tissue or brain samples. RVF5 features a dichlororhodol core with pyrrolidyl substitution at the nitrogen center. In mammalian cells under one-photon (1P) illumination, RVF5 demonstrates high voltage sensitivity (28% ΔF/F per 100 mV) and improved photostability relative to first-generation voltage sensors. This photostability enables multisite optical recordings from neurons lacking tuberous sclerosis complex 1, Tsc1, in a mouse model of genetic epilepsy. Using RVF5, we show that Tsc1 KO neurons exhibit increased activity relative to wild-type neurons and additionally show that the proportion of active neurons in the network increases with the loss of Tsc1. The high photostability and voltage sensitivity of RVF5 is recapitulated under 2P illumination. Finally, the ability to chemically tune the 2P absorption profile through the use of rhodol scaffolds affords the unique opportunity to image neuronal voltage changes in acutely prepared mouse brain slices using 2P illumination. Stimulation of the mouse hippocampus evoked spiking activity that was readily discerned with bath-applied RVF5, demonstrating the utility of RVF5 and molecular wire-based voltage sensors with 2P-optimized fluorophores for imaging voltage in intact brain tissue.

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.

A Decrease in Glomerular Endothelial Cells and Endothelial-mesenchymal Transition during Glomerulosclerosis in the Tensin2-deficient Mice (ICGN strain).

PubMed

Kato, Takashi; Mizuno, Shinya; Ito, Akihiko

2014-01-01

The ICR-derived glomerulonephritis (ICGN) mouse is a unique model of nephrotic syndrome, and albuminuria becomes evident in a neonatal stage, due to a genetic mutation of tensin2. We previously provided evidence that an apparent decrease in nephrin, caused by tensin2-deficiencient states, leads to podocytopathy, albuminuria and eventually, chronic renal failure. In general, glomerular endothelial cells (ECs) function as a barrier through tight attachment of glomerular basement membrane to podocytes, while decreased ECs can worsen renal failure. Nevertheless, it is still unknown whether glomerular ECs are altered under the tensin-2-deficient states during the manifestation of chronic renal failure. Herein, we examined the changes of glomerular ECs, with focus on the expression of PECAM-1 and VE-cadherin (EC-specific markers), or of α-SMA (myofibroblast marker) in this mouse model by histological methods. Compared with the non-nephrotic (+/nep) mice, the nephrotic (nep/nep) mice exhibited the reduced expression of PECAM-1, or of VE-cadherin, in glomerular area. Notably, some glomerular ECs showed the positive stainings for both PECAM-1 and α-SMA, suggesting endothelial-to-mesenchymal transition (EndoMT) during progression of glomerular sclerosis. This is the first report showing that a decrease in glomerular ECs, at least in part, via EndoMT is involved in tensin2-deficient pathological conditions.

Absence of social conditioned place preference in BTBR T+tf/J mice: relevance for social motivation testing in rodent models of autism

PubMed Central

Pearson, Brandon L.; Bettis, Jaclyn K.; Meyza, Ksenia Z.; Yamamoto, Lace Y.; Blanchard, D. Caroline; Blanchard, Robert J.

2012-01-01

A major goal of translation research in autism is to characterize the physiological and psychological processes underlying behavioral abnormalities. Since autism reflects impairments in social motivation, we modified the mouse three-chamber social approach apparatus for use as a social conditioned place preference arena. We paired one of two unique contexts with social interactions in juvenile mice for five or ten conditioning sessions in BTBR T+tf/J mice and a control strain with normal approach behaviors (C57BL/6J) since the BTBR T+tf/J inbred mouse strain displays a variety of behavioral alterations analogous to symptoms of autism spectrum disorders. While C57BL/6J mice formed a conditioned place preference to the context associated with social interactions, particularly those receiving ten days of conditioning, BTBR T+tf/J mice did not. Neither absence of social proximity nor avoidance due to high rates of autogrooming appeared to underlie the impaired positive incentive value of the unconditioned social stimulus in the BTBR T+tf/J strain. These data contribute to a growing body of evidence suggesting that the BTBR T+tf/J strain shows impairments in all diagnostic domains of autism including social motivation. Additionally, social conditioning testing might provide an important social motivation measure in other rodent models of neuropsychiatric disorders characterized by social abnormalities. PMID:22562042

Optimal parameters for near infrared fluorescence imaging of amyloid plaques in Alzheimer’s disease mouse models

PubMed Central

Raymond, S B; Kumar, A T N; Boas, D A; Bacskai, B J

2012-01-01

Amyloid-β plaques are an Alzheimer’s disease biomarker which present unique challenges for near-infrared fluorescence tomography because of size (<50 μm diameter) and distribution. We used high-resolution simulations of fluorescence in a digital Alzheimer’s disease mouse model to investigate the optimal fluorophore and imaging parameters for near-infrared fluorescence tomography of amyloid plaques. Fluorescence was simulated for amyloid-targeted probes with emission at 630 and 800 nm, plaque-to-background ratios from 1–1000, amyloid burden from 0–10%, and for transmission and reflection measurement geometries. Fluorophores with high plaque-to-background contrast ratios and 800 nm emission performed significantly better than current amyloid imaging probes. We tested idealized fluorophores in transmission and full-angle tomographic measurement schemes (900 source–detector pairs), with and without anatomical priors. Transmission reconstructions demonstrated strong linear correlation with increasing amyloid burden, but underestimated fluorescence yield and suffered from localization artifacts. Full-angle measurements did not improve upon the transmission reconstruction qualitatively or in semi-quantitative measures of accuracy; anatomical and initial-value priors did improve reconstruction localization and accuracy for both transmission and full-angle schemes. Region-based reconstructions, in which the unknowns were reduced to a few distinct anatomical regions, produced highly accurate yield estimates for cortex, hippocampus and brain regions, even with a reduced number of measurements (144 source–detector pairs). PMID:19794239

Increased placental nutrient transport in a novel mouse model of maternal obesity with fetal overgrowth.

PubMed

Rosario, Fredrick J; Kanai, Yoshikatsu; Powell, Theresa L; Jansson, Thomas

2015-08-01

To identify possible mechanisms linking obesity in pregnancy to increased fetal adiposity and growth, a unique mouse model of maternal obesity associated with fetal overgrowth was developed, and the hypothesis that maternal obesity causes up-regulation of placental nutrient transporter expression and activity was tested. C57BL/6J female mice were fed a control (C) or a high-fat/high-sugar (HF/HS) pelleted diet supplemented by ad libitum access to sucrose (20%) solution, mated, and studied at embryonic day 18.5. HF/HS diet increased maternal fat mass by 2.2-fold (P < 0.01) and resulted in glucose intolerance with normal fasting glucose. Maternal circulating insulin, leptin, and cholesterol were increased (P < 0.05) whereas total and high-molecular-weight adiponectin was decreased (P < 0.05). HF/HS diet increased fetal weight (+18%, P = 0.0005). In trophoblast plasma membranes (TPM) isolated from placentas of HF/HS-fed animals, protein expression of glucose transporter (GLUT) 1 and 3, sodium-coupled neutral amino acid transporter (SNAT) 2, and large neutral amino acid transporter 1 (LAT1) was increased. TPM System A and L amino acid transporter activity was increased in the HF/HS group. Up-regulation of specific placental nutrient transporter isoforms may constitute a mechanism underlying fetal overgrowth in maternal obesity. © 2015 The Obesity Society.

Entry of Botulinum Neurotoxin Subtypes A1 and A2 into Neurons

PubMed Central

Kroken, Abby R.; Blum, Faith C.; Zuverink, Madison

2016-01-01

ABSTRACT Botulinum neurotoxins (BoNTs) are the most toxic proteins for humans but also are common therapies for neurological diseases. BoNTs are dichain toxins, comprising an N-terminal catalytic domain (LC) disulfide bond linked to a C-terminal heavy chain (HC) which includes a translocation domain (HN) and a receptor binding domain (HC). Recently, the BoNT serotype A (BoNT/A) subtypes A1 and A2 were reported to possess similar potencies but different rates of cellular intoxication and pathology in a mouse model of botulism. The current study measured HCA1 and HCA2 entry into rat primary neurons and cultured Neuro2A cells. We found that there were two sequential steps during the association of BoNT/A with neurons. The initial step was ganglioside dependent, while the subsequent step involved association with synaptic vesicles. HCA1 and HCA2 entered the same population of synaptic vesicles and entered cells at similar rates. The primary difference was that HCA2 had a higher degree of receptor occupancy for cells and neurons than HcA1. Thus, HCA2 and HCA1 share receptors and entry pathway but differ in their affinity for receptor. The initial interaction of HCA1 and HCA2 with neurons may contribute to the unique pathologies of BoNT/A1 and BoNT/A2 in mouse models. PMID:27795365

Specific antibody for pesticide residue determination produced by antibody-pesticide complex

USDA-ARS?s Scientific Manuscript database

A new method for specific antibody production was developed using antibody (Ab)-pesticide complex as a unique immunogen. Parathion (PA) was the targeted pesticide, and rabbit polyclonal antibody (Pab) and mouse monoclonal antibody (Mab) were used as carrier proteins. The Ab-PA complexes were genera...

HUMAN GLYCERALDEHYDE 3-PHOSPHATE DEHYDROGENASE-2 (GAPD2) GENE IS EXPRESSED SPECIFICALLY IN SPERMATOGENIC CELLS

EPA Science Inventory

Although the process of glycolysis is highly conserved in eukaryotes, several glycolytic enzymes have unique structural or functional features in spermatogenic cells. We previously identified and characterized the mouse complementary DNA (cDNA) and a gene for 1 of these enzymes, ...

A novel mouse model of pediatric cardiac arrest and cardiopulmonary resuscitation reveals age-dependent neuronal sensitivities to ischemic injury

PubMed Central

Deng, G; Yonchek, JC; Quillinan, N; Strnad, FA; Exo, J; Herson, PS; Traystman, RJ

2014-01-01

Background Pediatric sudden cardiac arrest (CA) is an unfortunate and devastating condition, often leading to poor neurologic outcomes. However, little experimental data on the pathophysiology of pediatric CA is currently available due to the scarcity of animal models. New Method We developed a novel experimental model of pediatric cardiac arrest and cardiopulmonary resuscitation (CA/CPR) using postnatal day 20–25 mice. Adult (8–12 weeks) and pediatric (P20–25) mice were subjected to 6 min CA/CPR. Hippocampal CA1 and striatal neuronal injury were quantified 3 days after resuscitation by hematoxylin and eosin (H&E) and Fluoro-Jade B staining, respectively. Results Pediatric mice exhibited less neuronal injury in both CA1 hippocampal and striatal neurons compared to adult mice. Increasing ischemia time to 8 min CA/CPR resulted in an increase in hippocampal injury in pediatric mice, resulting in similar damage in adult and pediatric brains. In contrast, striatal injury in the pediatric brain following 6 or 8 min CA/CPR remained extremely low. As observed in adult mice, cardiac arrest causes delayed neuronal death in pediatric mice, with hippocampal CA1 neuronal damage maturing at 72 hours after insult. Finally, mild therapeutic hypothermia reduced hippocampal CA1 neuronal injury after pediatric CA/CPR. Comparison with Existing Method This is the first report of a cardiac arrest and CPR model of global cerebral ischemia in mice Conclusions Therefore, the mouse pediatric CA/CPR model we developed is unique and will provide an important new tool to the research community for the study of pediatric brain injury. PMID:24192226

Pluripotent cells in farm animals: state of the art and future perspectives.

PubMed

Nowak-Imialek, Monika; Niemann, Heiner

2012-01-01

Pluripotent cells, such as embryonic stem (ES) cells, embryonic germ cells and embryonic carcinoma cells are a unique type of cell because they remain undifferentiated indefinitely in in vitro culture, show self-renewal and possess the ability to differentiate into derivatives of the three germ layers. These capabilities make them a unique in vitro model for studying development, differentiation and for targeted modification of the genome. True pluripotent ESCs have only been described in the laboratory mouse and rat. However, rodent physiology and anatomy differ substantially from that of humans, detracting from the value of the rodent model for studies of human diseases and the development of cellular therapies in regenerative medicine. Recently, progress in the isolation of pluripotent cells in farm animals has been made and new technologies for reprogramming of somatic cells into a pluripotent state have been developed. Prior to clinical application of therapeutic cells differentiated from pluripotent stem cells in human patients, their survival and the absence of tumourigenic potential must be assessed in suitable preclinical large animal models. The establishment of pluripotent cell lines in farm animals may provide new opportunities for the production of transgenic animals, would facilitate development and validation of large animal models for evaluating ESC-based therapies and would thus contribute to the improvement of human and animal health. This review summarises the recent progress in the derivation of pluripotent and reprogrammed cells from farm animals. We refer to our recent review on this area, to which this article is complementary.

Mutagenicity testing with transgenic mice. Part II: Comparison with the mouse spot test

PubMed Central

Wahnschaffe, Ulrich; Bitsch, Annette; Kielhorn, Janet; Mangelsdorf, Inge

2005-01-01

The mouse spot test, an in vivo mutation assay, has been used to assess a number of chemicals. It is at present the only in vivo mammalian test system capable of detecting somatic gene mutations according to OECD guidelines (OECD guideline 484). It is however rather insensitive, animal consuming and expensive type of test. More recently several assays using transgenic animals have been developed. From data in the literature, the present study compares the results of in vivo testing of over twenty chemicals using the mouse spot test and compares them with results from the two transgenic mouse models with the best data base available, the lacI model (commercially available as the Big Blue® mouse), and the lacZ model (commercially available as the Muta™ Mouse). There was agreement in the results from the majority of substances. No differences were found in the predictability of the transgenic animal assays and the mouse spot test for carcinogenicity. However, from the limited data available, it seems that the transgenic mouse assay has several advantages over the mouse spot test and may be a suitable test system replacing the mouse spot test for detection of gene but not chromosome mutations in vivo. PMID:15676065

Metabolism and the Circadian Clock Converge

PubMed Central

Eckel-Mahan, Kristin

2013-01-01

Circadian rhythms occur in almost all species and control vital aspects of our physiology, from sleeping and waking to neurotransmitter secretion and cellular metabolism. Epidemiological studies from recent decades have supported a unique role for circadian rhythm in metabolism. As evidenced by individuals working night or rotating shifts, but also by rodent models of circadian arrhythmia, disruption of the circadian cycle is strongly associated with metabolic imbalance. Some genetically engineered mouse models of circadian rhythmicity are obese and show hallmark signs of the metabolic syndrome. Whether these phenotypes are due to the loss of distinct circadian clock genes within a specific tissue versus the disruption of rhythmic physiological activities (such as eating and sleeping) remains a cynosure within the fields of chronobiology and metabolism. Becoming more apparent is that from metabolites to transcription factors, the circadian clock interfaces with metabolism in numerous ways that are essential for maintaining metabolic homeostasis. PMID:23303907

A Mouse Model of the Cornea Pocket Assay for Angiogenesis Study

PubMed Central

Tang, Zhongshu; Zhang, Fan; Li, Yang; Arjunan, Pachiappan; Kumar, Anil; Lee, Chunsik; Li, Xuri

2011-01-01

A normal cornea is clear of vascular tissues. However, blood vessels can be induced to grow and survive in the cornea when potent angiogenic factors are administered 1. This uniqueness has made the cornea pocket assay one of the most used models for angiogenesis studies. The cornea composes multiple layers of cells. It is therefore possible to embed a pellet containing the angiogenic factor of interest in the cornea to investigate its angiogenic effect 2,3. Here, we provide a step by step demonstration of how to (I) produce the angiogenic factor-containing pellet (II) embed the pellet into the cornea (III) analyze the angiogenesis induced by the angiogenic factor of interest. Since the basic fibroblast growth factor (bFGF) is known as one of the most potent angiogenic factors 4, it is used here to induce angiogenesis in the cornea. PMID:21876523

Transgenic mice: an irreplaceable tool for the study of mammalian development and biology.

PubMed

Babinet, C

2000-11-01

Stable integration into the mouse genome of exogenous genetic information, i.e., the creation of transgenic mice, has become a privileged way of analyzing gene function in normal development and pathology. Both gene addition and gene replacement may be performed. This has allowed, in particular, the creation of mice in which precise mutations are introduced into a given gene. Furthermore, in recent years, strategies that induce the expression of a mutation in a given type of cell and/or at a given time in development have been developed. Thus, the transgenic methodology affords a unique and irreplaceable tool for the study of mammalian development and biology and for the creation of animal models for human genetic diseases.

The Mouse Genome Database (MGD): facilitating mouse as a model for human biology and disease.

PubMed

Eppig, Janan T; Blake, Judith A; Bult, Carol J; Kadin, James A; Richardson, Joel E

2015-01-01

The Mouse Genome Database (MGD, http://www.informatics.jax.org) serves the international biomedical research community as the central resource for integrated genomic, genetic and biological data on the laboratory mouse. To facilitate use of mouse as a model in translational studies, MGD maintains a core of high-quality curated data and integrates experimentally and computationally generated data sets. MGD maintains a unified catalog of genes and genome features, including functional RNAs, QTL and phenotypic loci. MGD curates and provides functional and phenotype annotations for mouse genes using the Gene Ontology and Mammalian Phenotype Ontology. MGD integrates phenotype data and associates mouse genotypes to human diseases, providing critical mouse-human relationships and access to repositories holding mouse models. MGD is the authoritative source of nomenclature for genes, genome features, alleles and strains following guidelines of the International Committee on Standardized Genetic Nomenclature for Mice. A new addition to MGD, the Human-Mouse: Disease Connection, allows users to explore gene-phenotype-disease relationships between human and mouse. MGD has also updated search paradigms for phenotypic allele attributes, incorporated incidental mutation data, added a module for display and exploration of genes and microRNA interactions and adopted the JBrowse genome browser. MGD resources are freely available to the scientific community. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Genetically engineered mouse models of craniopharyngioma: an opportunity for therapy development and understanding of tumor biology

PubMed Central

Martinez‐Barbera, Juan Pedro

2017-01-01

Abstract Adamantinomatous craniopharyngioma (ACP) is the commonest tumor of the sellar region in childhood. Two genetically engineered mouse models have been developed and are giving valuable insights into ACP biology. These models have identified novel pathways activated in tumors, revealed an important function of paracrine signalling and extended conventional theories about the role of organ‐specific stem cells in tumorigenesis. In this review, we summarize these mouse models, what has been learnt, their limitations and open questions for future research. We then discussed how these mouse models may be used to test novel therapeutics against potentially targetable pathways recently identified in human ACP. PMID:28414891

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.

Early biomarkers of doxorubicin-induced heart injury in a mouse model

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

Desai, Varsha G., E-mail: varsha.desai@fda.hhs.gov; Kwekel, Joshua C.; Vijay, Vikrant

Cardiac troponins, which are used as myocardial injury markers, are released in plasma only after tissue damage has occurred. Therefore, there is a need for identification of biomarkers of earlier events in cardiac injury to limit the extent of damage. To accomplish this, expression profiling of 1179 unique microRNAs (miRNAs) was performed in a chronic cardiotoxicity mouse model developed in our laboratory. Male B6C3F{sub 1} mice were injected intravenously with 3 mg/kg doxorubicin (DOX; an anti-cancer drug), or saline once a week for 2, 3, 4, 6, and 8 weeks, resulting in cumulative DOX doses of 6, 9, 12, 18,more » and 24 mg/kg, respectively. Mice were euthanized a week after the last dose. Cardiac injury was evidenced in mice exposed to 18 mg/kg and higher cumulative DOX dose whereas examination of hearts by light microscopy revealed cardiac lesions at 24 mg/kg DOX. Also, 24 miRNAs were differentially expressed in mouse hearts, with the expression of 1, 1, 2, 8, and 21 miRNAs altered at 6, 9, 12, 18, and 24 mg/kg DOX, respectively. A pro-apoptotic miR-34a was the only miRNA that was up-regulated at all cumulative DOX doses and showed a significant dose-related response. Up-regulation of miR-34a at 6 mg/kg DOX may suggest apoptosis as an early molecular change in the hearts of DOX-treated mice. At 12 mg/kg DOX, up-regulation of miR-34a was associated with down-regulation of hypertrophy-related miR-150; changes observed before cardiac injury. These findings may lead to the development of biomarkers of earlier events in DOX-induced cardiotoxicity that occur before the release of cardiac troponins. - Highlights: • Upregulation of miR-34a before doxorubicin-induced cardiac tissue injury • Apoptosis might be an early event in mouse heart during doxorubicin treatment. • Expression of miR-150 declined before doxorubicin-induced cardiac tissue injury.« less

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...

Unique nonstructural proteins of Pneumonia Virus of Mice (PVM) promote degradation of interferon (IFN) pathway components and IFN-stimulated gene proteins.

PubMed

Dhar, Jayeeta; Barik, Sailen

2016-12-01

Pneumonia Virus of Mice (PVM) is the only virus that shares the Pneumovirus genus of the Paramyxoviridae family with Respiratory Syncytial Virus (RSV). A deadly mouse pathogen, PVM has the potential to serve as a robust animal model of RSV infection, since human RSV does not fully replicate the human pathology in mice. Like RSV, PVM also encodes two nonstructural proteins that have been implicated to suppress the IFN pathway, but surprisingly, they exhibit no sequence similarity with their RSV equivalents. The molecular mechanism of PVM NS function, therefore, remains unknown. Here, we show that recombinant PVM NS proteins degrade the mouse counterparts of the IFN pathway components. Proteasomal degradation appears to be mediated by ubiquitination promoted by PVM NS proteins. Interestingly, NS proteins of PVM lowered the levels of several ISG (IFN-stimulated gene) proteins as well. These results provide a molecular foundation for the mechanisms by which PVM efficiently subverts the IFN response of the murine cell. They also reveal that in spite of their high sequence dissimilarity, the two pneumoviral NS proteins are functionally and mechanistically similar.

Signaling hierarchy regulating human endothelial cell development.

PubMed

Kelly, Melissa A; Hirschi, Karen K

2009-05-01

Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these studies. Using human embryonic stem cells as a model system, we were able to reproducibly and robustly generate differentiated endothelial cells via coculture on OP9 marrow stromal cells. We found that, in contrast to studies in the mouse, bFGF and VEGF had no specific effects on the initiation of human vasculogenesis. However, exogenous Ihh promoted endothelial cell differentiation, as evidenced by increased production of cells with cobblestone morphology that coexpress multiple endothelial-specific genes and proteins, form lumens, and exhibit DiI-AcLDL uptake. Inhibition of BMP signaling using Noggin or BMP4, specifically, using neutralizing antibodies suppressed endothelial cell formation; whereas, addition of rhBMP4 to cells treated with the hedgehog inhibitor cyclopamine rescued endothelial cell development. Our studies revealed that Ihh promoted human endothelial cell differentiation from pluripotent hES cells via BMP signaling, providing novel insights applicable to modulating human endothelial cell formation and vascular regeneration for human clinical therapies.

Lack of species-specific difference in pulmonary function when using mouse versus human plasma in a mouse model of hemorrhagic shock.

PubMed

Peng, Zhanglong; Pati, Shibani; Fontaine, Magali J; Hall, Kelly; Herrera, Anthony V; Kozar, Rosemary A

2016-11-01

Clinical studies have demonstrated that the early and empiric use of plasma improves survival after hemorrhagic shock. We have demonstrated in rodent models of hemorrhagic shock that resuscitation with plasma is protective to the lungs compared with lactated Ringer's solution. As our long-term objective is to determine the molecular mechanisms that modulate plasma's protective effects in injured bleeding patients, we have used human plasma in a mouse model of hemorrhagic shock. The goal of the current experiments is to determine if there are significant adverse effects on lung injury when using human versus mouse plasma in an established murine model of hemorrhagic shock and laparotomy. Mice underwent laparotomy and 90 minutes of hemorrhagic shock to a mean arterial pressure (MAP) of 35 ± 5 mm Hg followed by resuscitation at 1× shed blood using either mouse fresh frozen plasma (FFP), human FFP, or human lyophilized plasma. Mean arterial pressure was recorded during shock and for the first 30 minutes of resuscitation. After 3 hours, animals were killed, and lungs collected for analysis. There was a significant increase in early MAP when mouse FFP was used to resuscitate animals compared with human FFP or human lyophilized plasma. However, despite these differences, analysis of the mouse lungs revealed no significant differences in pulmonary histopathology, lung permeability, or lung edema between all three plasma groups. Analysis of neutrophil infiltration in the lungs revealed that mouse FFP decreased neutrophil influx as measured by neutrophil staining; however, myeloperoxidase immunostaining revealed no significant differences in between groups. The study of human plasma in a mouse model of hemorrhagic shock is feasible but does reveal some differences compared with mouse plasma-based resuscitation in physiologic measures such as MAP postresuscitation. Measures of end organ function such as lung injury appear to be comparable in this acute model of hemorrhagic shock and resuscitation.

In vivo quantitative bioluminescence tomography using heterogeneous and homogeneous mouse models.

PubMed

Liu, Junting; Wang, Yabin; Qu, Xiaochao; Li, Xiangsi; Ma, Xiaopeng; Han, Runqiang; Hu, Zhenhua; Chen, Xueli; Sun, Dongdong; Zhang, Rongqing; Chen, Duofang; Chen, Dan; Chen, Xiaoyuan; Liang, Jimin; Cao, Feng; Tian, Jie

2010-06-07

Bioluminescence tomography (BLT) is a new optical molecular imaging modality, which can monitor both physiological and pathological processes by using bioluminescent light-emitting probes in small living animal. Especially, this technology possesses great potential in drug development, early detection, and therapy monitoring in preclinical settings. In the present study, we developed a dual modality BLT prototype system with Micro-computed tomography (MicroCT) registration approach, and improved the quantitative reconstruction algorithm based on adaptive hp finite element method (hp-FEM). Detailed comparisons of source reconstruction between the heterogeneous and homogeneous mouse models were performed. The models include mice with implanted luminescence source and tumor-bearing mice with firefly luciferase report gene. Our data suggest that the reconstruction based on heterogeneous mouse model is more accurate in localization and quantification than the homogeneous mouse model with appropriate optical parameters and that BLT allows super-early tumor detection in vivo based on tomographic reconstruction of heterogeneous mouse model signal.

Of Mice and Men: Comparative Analysis of Neuro-Inflammatory Mechanisms in Human and Mouse Using Cause-and-Effect Models.

PubMed

Kodamullil, Alpha Tom; Iyappan, Anandhi; Karki, Reagon; Madan, Sumit; Younesi, Erfan; Hofmann-Apitius, Martin

2017-01-01

Perturbance in inflammatory pathways have been identified as one of the major factors which leads to neurodegenerative diseases (NDD). Owing to the limited access of human brain tissues and the immense complexity of the brain, animal models, specifically mouse models, play a key role in advancing the NDD field. However, many of these mouse models fail to reproduce the clinical manifestations and end points of the disease. NDD drugs, which passed the efficacy test in mice, were repeatedly not successful in clinical trials. There are numerous studies which are supporting and opposing the applicability of mouse models in neuroinflammation and NDD. In this paper, we assessed to what extend a mouse can mimic the cellular and molecular interactions in humans at a mechanism level. Based on our mechanistic modeling approach, we investigate the failure of a neuroinflammation targeted drug in the late phases of clinical trials based on the comparative analyses between the two species.

NCI Mouse Repository | FNLCR Staging

Cancer.gov

The NCI Mouse Repository is an NCI-funded resource for mouse cancer models and associated strains. The repository makes strains available to all members of the scientific community (academic, non-profit, and commercial). NCI Mouse Repository strains

Evaluation of 11C-acetate and 18F-FDG PET/CT in mouse multidrug resistance gene-2 deficient mouse model of hepatocellular carcinoma.

PubMed

Territo, Paul R; Maluccio, Mary; Riley, Amanda A; McCarthy, Brian P; Fletcher, James; Tann, Mark; Saxena, Romil; Skill, Nicholas J

2015-05-16

Hepatocellular carcinoma (HCC) remains a global health problem with unique diagnostic and therapeutic challenges, including difficulties in identifying the highest risk patients. Previous work from our lab has established the murine multidrug resistance-2 mouse (MDR2) model of HCC as a reasonable preclinical model that parallels the changes seen in human inflammatory associated HCC. The purpose of this study is to evaluate modalities of PET/CT in MDR2(-/-) mice in order to facilitate therapeutic translational studies from bench to bedside. 18F-FDG and 11C-acetate PET/CT was performed on 12 m MDR2(-/-) mice (n = 3/tracer) with HCC and 12 m MDR2(-/+) control mice (n = 3/tracer) without HCC. To compare PET/CT to biological markers of HCC and cellular function, serum alpha-fetoprotein (AFP), lysophosphatidic acid (LPA), cAMP and hepatic tumor necrosis factor α (TNFα) were quantified in 3-12 m MDR2(-/-) (n = 10) mice using commercially available ELISA analysis. To translate results in mice to patients 11C-acetate PET/CT was also performed in 8 patents suspected of HCC recurrence following treatment and currently on the liver transplant wait list. Hepatic18F-FDG metabolism was not significantly increased in MDR2(-/-) mice. In contrast, hepatic 11C-acetate metabolism was significantly elevated in MDR2(-/-) mice when compared to MDR2(-/+) controls. Serum AFP and LPA levels increased in MDR2(-/-) mice contemporaneous with the emergence of HCC. This was accompanied by a significant decrease in serum cAMP levels and an increase in hepatic TNFα. In patients suspected of HCC recurrence there were 5 true positives, 2 true negatives and 1 suspected false 11C-acetate negative. Hepatic 11C-acetate PET/CT tracks well with HCC in MDR2(-/-) mice and patients with underlying liver disease. Consequently 11C-acetate PET/CT is well suited to study (1) HCC emergence/progression in patients and (2) reduce animal numbers required to study new chemotherapeutics in murine models of HCC.

Modeling recent human evolution in mice by expression of a selected EDAR variant

PubMed Central

Kamberov, Yana G.; Wang, Sijia; Tan, Jingze; Gerbault, Pascale; Wark, Abigail; Tan, Longzhi; Yang, Yajun; Li, Shilin; Tang, Kun; Chen, Hua; Powell, Adam; Itan, Yuval; Fuller, Dorian; Lohmueller, Jason; Mao, Junhao; Schachar, Asa; Paymer, Madeline; Hostetter, Elizabeth; Byrne, Elizabeth; Burnett, Melissa; McMahon, Andrew P.; Thomas, Mark G.; Lieberman, Daniel E.; Jin, Li; Tabin, Clifford J.; Morgan, Bruce A.; Sabeti, Pardis C.

2013-01-01

Summary An adaptive variant of the human Ectodysplasin receptor, EDARV370A, is one of the strongest candidates of recent positive selection from genome-wide scans. We have modeled EDAR370A in mice and characterized its phenotype and evolutionary origins in humans. Our computational analysis suggests the allele arose in Central China approximately 30,000 years ago. Although EDAR370A has been associated with increased scalp hair thickness and changed tooth morphology in humans, its direct biological significance and potential adaptive role remain unclear. We generated a knock-in mouse model and find that, as in humans, hair thickness is increased in EDAR370A mice. We identify novel biological targets affected by the mutation, including mammary and eccrine glands. Building on these results, we find that EDAR370A is associated with an increased number of active eccrine glands in the Han Chinese. This interdisciplinary approach yields unique insight into the generation of adaptive variation among modern humans. PMID:23415220

Surgical Models of Roux-en-Y Gastric Bypass Surgery and Sleeve Gastrectomy in Rats and Mice

PubMed Central

Bruinsma, Bote G.; Uygun, Korkut; Yarmush, Martin L.; Saeidi, Nima

2015-01-01

Bariatric surgery is the only definitive solution currently available for the present obesity pandemic. These operations typically involve reconfiguration of gastrointestinal tract anatomy and impose profound metabolic and physiological benefits, such as substantially reducing body weight and ameliorating type II diabetes. Therefore, animal models of these surgeries offer unique and exciting opportunities to delineate the underlying mechanisms that contribute to the resolution of obesity and diabetes. Here we describe a standardized procedure for mouse and rat models of Roux-en-Y gastric bypass (80–90 minutes operative time) and sleeve gastrectomy (30–45 minutes operative time), which, to a high degree resemble operations in human. We also provide detailed protocols for both pre- and post-operative techniques that ensure a high success rate in the operations. These protocols provide the opportunity to mechanistically investigate the systemic effects of the surgical interventions, such as regulation of body weight, glucose homeostasis, and gut microbiome. PMID:25719268

[Mice are not Men and yet… how humanized mice inform us about human infectious diseases].

PubMed

Cachat, Anne; Villaudy, Julien; Rigal, Dominique; Gazzolo, Louis; Duc Dodon, Madeleine

2012-01-01

The study of human pathologies is often limited by the absence of animal models which are robust, cost-effective and reproduce the hallmarks of human infections. While mice have been frequently employed to study human diseases, many of important pathogens display unique human tropism. These last two decades the graft of human progenitor cells or tissues into -immunodeficient mice has allowed the elaboration of so called humanized mice. Humanized mouse technology has made rapid progress, and it is now possible to achieve high levels of human chimerism in various organs and tissues, particularly the immune system and the liver. The review briefly summarizes the different models of humanized mice available for in vivo experiments. With a focus on lymphotropic, monocytotropic and hepatotropic viruses, we here discuss the current status and future prospects of these models for studying the pathogenesis of infectious diseases. Furthermore, they provide a powerful tool for the development of innovative therapies. © 2012 médecine/sciences – Inserm / SRMS.

Sensitive and quantitative detection of botulinum neurotoxin in neurons derived from mouse embryonic stem cells.

PubMed

Pellett, Sabine; Du, Zhong-wei; Pier, Christina L; Tepp, William H; Zhang, Su-chun; Johnson, Eric A

2011-01-07

Botulinum neurotoxins (BoNTs), the most poisonous protein toxins known, represent a serious bioterrorism threat but are also used as a unique and important bio-pharmaceutical to treat an increasing myriad of neurological disorders. The only currently accepted detection method by the United States Food and Drug Administration for biological activity of BoNTs and for potency determination of pharmaceutical preparations is the mouse bioassay (MBA). Recent advances have indicated that cell-based assays using primary neuronal cells can provide an equally sensitive and robust detection platform as the MBA to reliably and quantitatively detect biologically active BoNTs. This study reports for the first time a BoNT detection assay using mouse embryonic stem cells to produce a neuronal cell culture. The data presented indicate that this assay can reliably detect BoNT/A with a similar sensitivity as the MBA. Published by Elsevier Inc.

Live imaging and genetic analysis of mouse notochord formation reveals regional morphogenetic mechanisms.

PubMed

Yamanaka, Yojiro; Tamplin, Owen J; Beckers, Anja; Gossler, Achim; Rossant, Janet

2007-12-01

The node and notochord have been extensively studied as signaling centers in the vertebrate embryo. The morphogenesis of these tissues, particularly in mouse, is not well understood. Using time-lapse live imaging and cell lineage tracking, we show the notochord has distinct morphogenetic origins along the anterior-posterior axis. The anterior head process notochord arises independently of the node by condensation of dispersed cells. The trunk notochord is derived from the node and forms by convergent extension. The tail notochord forms by node-derived progenitors that actively migrate toward the posterior. We also reveal distinct genetic regulation within these different regions. We show that Foxa2 compensates for and genetically interacts with Noto in the trunk notochord, and that Noto has an evolutionarily conserved role in regulating axial versus paraxial cell fate. Therefore, we propose three distinct regions within the mouse notochord, each with unique morphogenetic origins.

High-throughput discovery of novel developmental phenotypes

PubMed Central

Dickinson, Mary E.; Flenniken, Ann M.; Ji, Xiao; Teboul, Lydia; Wong, Michael D.; White, Jacqueline K.; Meehan, Terrence F.; Weninger, Wolfgang J.; Westerberg, Henrik; Adissu, Hibret; Baker, Candice N.; Bower, Lynette; Brown, James M.; Caddle, L. Brianna; Chiani, Francesco; Clary, Dave; Cleak, James; Daly, Mark J.; Denegre, James M.; Doe, Brendan; Dolan, Mary E.; Edie, Sarah M.; Fuchs, Helmut; Gailus-Durner, Valerie; Galli, Antonella; Gambadoro, Alessia; Gallegos, Juan; Guo, Shiying; Horner, Neil R.; Hsu, Chih-wei; Johnson, Sara J.; Kalaga, Sowmya; Keith, Lance C.; Lanoue, Louise; Lawson, Thomas N.; Lek, Monkol; Mark, Manuel; Marschall, Susan; Mason, Jeremy; McElwee, Melissa L.; Newbigging, Susan; Nutter, Lauryl M.J.; Peterson, Kevin A.; Ramirez-Solis, Ramiro; Rowland, Douglas J.; Ryder, Edward; Samocha, Kaitlin E.; Seavitt, John R.; Selloum, Mohammed; Szoke-Kovacs, Zsombor; Tamura, Masaru; Trainor, Amanda G; Tudose, Ilinca; Wakana, Shigeharu; Warren, Jonathan; Wendling, Olivia; West, David B.; Wong, Leeyean; Yoshiki, Atsushi; MacArthur, Daniel G.; Tocchini-Valentini, Glauco P.; Gao, Xiang; Flicek, Paul; Bradley, Allan; Skarnes, William C.; Justice, Monica J.; Parkinson, Helen E.; Moore, Mark; Wells, Sara; Braun, Robert E.; Svenson, Karen L.; de Angelis, Martin Hrabe; Herault, Yann; Mohun, Tim; Mallon, Ann-Marie; Henkelman, R. Mark; Brown, Steve D.M.; Adams, David J.; Lloyd, K.C. Kent; McKerlie, Colin; Beaudet, Arthur L.; Bucan, Maja; Murray, Stephen A.

2016-01-01

Approximately one third of all mammalian genes are essential for life. Phenotypes resulting from mouse knockouts of these genes have provided tremendous insight into gene function and congenital disorders. As part of the International Mouse Phenotyping Consortium effort to generate and phenotypically characterize 5000 knockout mouse lines, we have identified 410 lethal genes during the production of the first 1751 unique gene knockouts. Using a standardised phenotyping platform that incorporates high-resolution 3D imaging, we identified novel phenotypes at multiple time points for previously uncharacterized genes and additional phenotypes for genes with previously reported mutant phenotypes. Unexpectedly, our analysis reveals that incomplete penetrance and variable expressivity are common even on a defined genetic background. In addition, we show that human disease genes are enriched for essential genes identified in our screen, thus providing a novel dataset that facilitates prioritization and validation of mutations identified in clinical sequencing efforts. PMID:27626380

Structure and inhibition analysis of the mouse SAD-B C-terminal fragment.

PubMed

Ma, Hui; Wu, Jing-Xiang; Wang, Jue; Wang, Zhi-Xin; Wu, Jia-Wei

2016-10-01

The SAD (synapses of amphids defective) kinases, including SAD-A and SAD-B, play important roles in the regulation of neuronal development, cell cycle, and energy metabolism. Our recent study of mouse SAD-A identified a unique autoinhibitory sequence (AIS), which binds at the junction of the kinase domain (KD) and the ubiquitin-associated (UBA) domain and exerts autoregulation in cooperation with UBA. Here, we report the crystal structure of the mouse SAD-B C-terminal fragment including the AIS and the kinase-associated domain 1 (KA1) at 2.8 Å resolution. The KA1 domain is structurally conserved, while the isolated AIS sequence is highly flexible and solvent-accessible. Our biochemical studies indicated that the SAD-B AIS exerts the same autoinhibitory role as that in SAD-A. We believe that the flexible isolated AIS sequence is readily available for interaction with KD-UBA and thus inhibits SAD-B activity.

Analysis of mammalian gene function through broad based phenotypic screens across a consortium of mouse clinics

PubMed Central

Adams, David J; Adams, Niels C; Adler, Thure; Aguilar-Pimentel, Antonio; Ali-Hadji, Dalila; Amann, Gregory; André, Philippe; Atkins, Sarah; Auburtin, Aurelie; Ayadi, Abdel; Becker, Julien; Becker, Lore; Bedu, Elodie; Bekeredjian, Raffi; Birling, Marie-Christine; Blake, Andrew; Bottomley, Joanna; Bowl, Mike; Brault, Véronique; Busch, Dirk H; Bussell, James N; Calzada-Wack, Julia; Cater, Heather; Champy, Marie-France; Charles, Philippe; Chevalier, Claire; Chiani, Francesco; Codner, Gemma F; Combe, Roy; Cox, Roger; Dalloneau, Emilie; Dierich, André; Di Fenza, Armida; Doe, Brendan; Duchon, Arnaud; Eickelberg, Oliver; Esapa, Chris T; El Fertak, Lahcen; Feigel, Tanja; Emelyanova, Irina; Estabel, Jeanne; Favor, Jack; Flenniken, Ann; Gambadoro, Alessia; Garrett, Lilian; Gates, Hilary; Gerdin, Anna-Karin; Gkoutos, George; Greenaway, Simon; Glasl, Lisa; Goetz, Patrice; Da Cruz, Isabelle Goncalves; Götz, Alexander; Graw, Jochen; Guimond, Alain; Hans, Wolfgang; Hicks, Geoff; Hölter, Sabine M; Höfler, Heinz; Hancock, John M; Hoehndorf, Robert; Hough, Tertius; Houghton, Richard; Hurt, Anja; Ivandic, Boris; Jacobs, Hughes; Jacquot, Sylvie; Jones, Nora; Karp, Natasha A; Katus, Hugo A; Kitchen, Sharon; Klein-Rodewald, Tanja; Klingenspor, Martin; Klopstock, Thomas; Lalanne, Valerie; Leblanc, Sophie; Lengger, Christoph; le Marchand, Elise; Ludwig, Tonia; Lux, Aline; McKerlie, Colin; Maier, Holger; Mandel, Jean-Louis; Marschall, Susan; Mark, Manuel; Melvin, David G; Meziane, Hamid; Micklich, Kateryna; Mittelhauser, Christophe; Monassier, Laurent; Moulaert, David; Muller, Stéphanie; Naton, Beatrix; Neff, Frauke; Nolan, Patrick M; Nutter, Lauryl MJ; Ollert, Markus; Pavlovic, Guillaume; Pellegata, Natalia S; Peter, Emilie; Petit-Demoulière, Benoit; Pickard, Amanda; Podrini, Christine; Potter, Paul; Pouilly, Laurent; Puk, Oliver; Richardson, David; Rousseau, Stephane; Quintanilla-Fend, Leticia; Quwailid, Mohamed M; Racz, Ildiko; Rathkolb, Birgit; Riet, Fabrice; Rossant, Janet; Roux, Michel; Rozman, Jan; Ryder, Ed; Salisbury, Jennifer; Santos, Luis; Schäble, Karl-Heinz; Schiller, Evelyn; Schrewe, Anja; Schulz, Holger; Steinkamp, Ralf; Simon, Michelle; Stewart, Michelle; Stöger, Claudia; Stöger, Tobias; Sun, Minxuan; Sunter, David; Teboul, Lydia; Tilly, Isabelle; Tocchini-Valentini, Glauco P; Tost, Monica; Treise, Irina; Vasseur, Laurent; Velot, Emilie; Vogt-Weisenhorn, Daniela; Wagner, Christelle; Walling, Alison; Weber, Bruno; Wendling, Olivia; Westerberg, Henrik; Willershäuser, Monja; Wolf, Eckhard; Wolter, Anne; Wood, Joe; Wurst, Wolfgang; Yildirim, Ali Önder; Zeh, Ramona; Zimmer, Andreas; Zimprich, Annemarie

2015-01-01

The function of the majority of genes in the mouse and human genomes remains unknown. The mouse ES cell knockout resource provides a basis for characterisation of relationships between gene and phenotype. The EUMODIC consortium developed and validated robust methodologies for broad-based phenotyping of knockouts through a pipeline comprising 20 disease-orientated platforms. We developed novel statistical methods for pipeline design and data analysis aimed at detecting reproducible phenotypes with high power. We acquired phenotype data from 449 mutant alleles, representing 320 unique genes, of which half had no prior functional annotation. We captured data from over 27,000 mice finding that 83% of the mutant lines are phenodeviant, with 65% demonstrating pleiotropy. Surprisingly, we found significant differences in phenotype annotation according to zygosity. Novel phenotypes were uncovered for many genes with unknown function providing a powerful basis for hypothesis generation and further investigation in diverse systems. PMID:26214591

Characterization of a new Gsx2-cre line in the developing mouse telencephalon.

PubMed

Qin, Shenyue; Madhavan, Mayur; Waclaw, Ronald R; Nakafuku, Masato; Campbell, Kenneth

2016-10-01

In this study, we generated a transgenic mouse line driving Cre and EGFP expression with two putative cis-regulatory modules (CRMs) (i.e., hs687 and hs678) upstream of the homeobox gene Gsx2 (formerly Gsh2), a critical gene for establishing lateral ganglionic eminence (LGE) identity. The combination of these two CRMs drives transgene expression within the endogenous Gsx2 expression domains along the anterior-posterior neuraxis. By crossing this transgenic line with the Rosa tdTomato (Ai14) reporter mouse line, we observed a unique recombination pattern in the lateral ventral telencephalon, namely the LGE and the dorsal half of the medial GE (MGE), but not in the septum. We found robust recombination in many cell types derived from these embryonic regions, including olfactory bulb and amygdala interneurons and striatal projection neurons from the LGE, as well as cortical interneurons from the MGE and caudal GE (CGE). In summary, this transgenic mouse line represents a new tool for genetic manipulation in the LGE/CGE and the dorsal half of MGE. © 2016 Wiley Periodicals, Inc.

The role of early development in mammalian limb diversification: a descriptive comparison of early limb development between the Natal long-fingered bat (Miniopterus natalensis) and the mouse (Mus musculus).

PubMed

Hockman, Dorit; Mason, Mandy K; Jacobs, David S; Illing, Nicola

2009-04-01

Comparative embryology expands our understanding of unique limb structures, such as that found in bats. Bat forelimb digits 2 to 5 are differentially elongated and joined by webbing, while the hindlimb digits are of similar length in many species. We compare limb development between the mouse and the Natal long-fingered bat, Miniopterus natalensis, to pinpoint the stage at which their limbs begin to differ. The bat forelimb differs from the mouse at Carollia stage (CS) 14 with the appearance of the wing membrane primordia. This difference is enhanced at CS 15 with the posterior expansion of the hand plate. The bat hindlimb begins to differ from the mouse between CS 15 and 16 when the foot plate undergoes a proximal expansion resulting in digit primordia of very similar length. Our findings support recent gene expression studies, which reveal a role for early patterning in the development of the bat limb. Copyright 2009 Wiley-Liss, Inc.

Chromatin configuration and epigenetic landscape at the sex chromosome bivalent during equine spermatogenesis

PubMed Central

Baumann, Claudia; Daly, Christopher M.; McDonnell, Sue M.; Viveiros, Maria M.; De La Fuente, Rabindranath

2011-01-01

Pairing of the sex chromosomes during mammalian meiosis is characterized by the formation of a unique heterochromatin structure at the XY body. The mechanisms underlying the formation of this nuclear domain are reportedly highly conserved from marsupials to mammals. In this study, we demonstrate that in contrast to all eutherian species studied to date, partial synapsis of the heterologous sex chromosomes during pachytene stage in the horse is not associated with the formation of a typical macrochromatin domain at the XY body. While phosphorylated histone H2AX (γH2AX) and macroH2A1.2 are present as a diffuse signal over the entire macrochromatin domain in mouse pachytene spermatocytes, γH2AX, macroH2A1.2, and the cohesin subunit SMC3 are preferentially enriched at meiotic sex chromosome cores in equine spermatocytes. Moreover, although several histone modifications associated with this nuclear domain in the mouse such as H3K4me2 and ubH2A are conspicuously absent in the equine XY body, prominent RNA polymerase II foci persist at the sex chromosomes. Thus, the localization of key marker proteins and histone modifications associated with the XY body in the horse differs significantly from all other mammalian systems described. These results demonstrate that the epigenetic landscape and heterochromatinization of the equine XY body might be regulated by alternative mechanisms and that some features of XY body formation may be evolutionary divergent in the domestic horse. We propose equine spermatogenesis as a unique model system for the study of the regulatory networks leading to the epigenetic control of gene expression during XY body formation. PMID:21274552

An extended Kalman filter for mouse tracking.

PubMed

Choi, Hongjun; Kim, Mingi; Lee, Onseok

2018-05-19

Animal tracking is an important tool for observing behavior, which is useful in various research areas. Animal specimens can be tracked using dynamic models and observation models that require several types of data. Tracking mouse has several barriers due to the physical characteristics of the mouse, their unpredictable movement, and cluttered environments. Therefore, we propose a reliable method that uses a detection stage and a tracking stage to successfully track mouse. The detection stage detects the surface area of the mouse skin, and the tracking stage implements an extended Kalman filter to estimate the state variables of a nonlinear model. The changes in the overall shape of the mouse are tracked using an oval-shaped tracking model to estimate the parameters for the ellipse. An experiment is conducted to demonstrate the performance of the proposed tracking algorithm using six video images showing various types of movement, and the ground truth values for synthetic images are compared to the values generated by the tracking algorithm. A conventional manual tracking method is also applied to compare across eight experimenters. Furthermore, the effectiveness of the proposed tracking method is also demonstrated by applying the tracking algorithm with actual images of mouse. Graphical abstract.

Mouse Models for Down Syndrome-Associated Developmental Cognitive Disabilities

PubMed Central

Liu, Chunhong; Belichenko, Pavel V.; Zhang, Li; Fu, Dawei; Kleschevnikov, Alexander M.; Baldini, Antonio; Antonarakis, Stylianos E.; Mobley, William C.; Yu, Y. Eugene

2011-01-01

Down syndrome (DS) is mainly caused by the presence of an extra copy of human chromosome 21 (Hsa21) and is a leading genetic cause for developmental cognitive disabilities in humans. The mouse is a premier model organism for DS because the regions on Hsa21 are syntenically conserved with three regions in the mouse genome, which are located on mouse chromosome 10 (Mmu10), Mmu16 and Mmu17. With the advance of chromosomal manipulation technologies, new mouse mutants have been generated to mimic DS at both the genotypic and phenotypic levels. Further mouse-based molecular genetic studies in the future may lead to the unraveling of the mechanisms underlying DS-associated developmental cognitive disabilities, which would lay the groundwork for developing effective treatments for this phenotypic manifestation. In this review, we will discuss recent progress and future challenges in modeling DS-associated developmental cognitive disability in mice with an emphasis on hippocampus-related phenotypes. PMID:21865664

Methods in Molecular Biology Mouse Genetics: Methods and Protocols | Center for Cancer Research

Cancer.gov

Mouse Genetics: Methods and Protocols provides selected mouse genetic techniques and their application in modeling varieties of human diseases. The chapters are mainly focused on the generation of different transgenic mice to accomplish the manipulation of genes of interest, tracing cell lineages, and modeling human diseases.

Use of mouse models to study the mechanisms and consequences of RBC clearance

PubMed Central

Hod, E. A.; Arinsburg, S. A.; Francis, R. O.; Hendrickson, J. E.; Zimring, J. C.; Spitalnik, S. L.

2013-01-01

Mice provide tractable animal models for studying the pathophysiology of various human disorders. This review discusses the use of mouse models for understanding red-blood-cell (RBC) clearance. These models provide important insights into the pathophysiology of various clinically relevant entities, such as autoimmune haemolytic anaemia, haemolytic transfusion reactions, other complications of RBC transfusions and immunomodulation by Rh immune globulin therapy. Mouse models of both antibody- and non-antibody-mediated RBC clearance are reviewed. Approaches for exploring unanswered questions in transfusion medicine using these models are also discussed. PMID:20345515

Generation Of A Mouse Model For Schwannomatosis

DTIC Science & Technology

2010-09-01

TITLE: Generation of a Mouse Model for Schwannomatosis PRINCIPAL INVESTIGATOR: Long-Sheng Chang, Ph.D. CONTRACTING ORGANIZATION: The...Annual 3. DATES COVERED (From - To) 1 Sep 2009 - 31 Aug 2010 4. TITLE AND SUBTITLE Generation of a Mouse Model for Schwannomatosis 5a. CONTRACT...hypothesis involving inactivation of both the INI1/SNF5 and NF2 tumor suppressor genes in the formation of schwannomatosis -associated tumors. To

Mouse Genome Database: From sequence to phenotypes and disease models

PubMed Central

Richardson, Joel E.; Kadin, James A.; Smith, Cynthia L.; Blake, Judith A.; Bult, Carol J.

2015-01-01

Summary The Mouse Genome Database (MGD, www.informatics.jax.org) is the international scientific database for genetic, genomic, and biological data on the laboratory mouse to support the research requirements of the biomedical community. To accomplish this goal, MGD provides broad data coverage, serves as the authoritative standard for mouse nomenclature for genes, mutants, and strains, and curates and integrates many types of data from literature and electronic sources. Among the key data sets MGD supports are: the complete catalog of mouse genes and genome features, comparative homology data for mouse and vertebrate genes, the authoritative set of Gene Ontology (GO) annotations for mouse gene functions, a comprehensive catalog of mouse mutations and their phenotypes, and a curated compendium of mouse models of human diseases. Here, we describe the data acquisition process, specifics about MGD's key data areas, methods to access and query MGD data, and outreach and user help facilities. genesis 53:458–473, 2015. © 2015 The Authors. Genesis Published by Wiley Periodicals, Inc. PMID:26150326

Establishing a laboratory animal model from a transgenic animal: RasH2 mice as a model for carcinogenicity studies in regulatory science.

PubMed

Urano, K; Tamaoki, N; Nomura, T

2012-01-01

Transgenic animal models have been used in small numbers in gene function studies in vivo for a period of time, but more recently, the use of a single transgenic animal model has been approved as a second species, 6-month alternative (to the routine 2-year, 2-animal model) used in short-term carcinogenicity studies for generating regulatory application data of new drugs. This article addresses many of the issues associated with the creation and use of one of these transgenic models, the rasH2 mouse, for regulatory science. The discussion includes strategies for mass producing mice with the same stable phenotype, including constructing the transgene, choosing a founder mouse, and controlling both the transgene and background genes; strategies for developing the model for regulatory science, including measurements of carcinogen susceptibility, stability of a large-scale production system, and monitoring for uniform carcinogenicity responses; and finally, efficient use of the transgenic animal model on study. Approximately 20% of mouse carcinogenicity studies for new drug applications in the United States currently use transgenic models, typically the rasH2 mouse. The rasH2 mouse could contribute to animal welfare by reducing the numbers of animals used as well as reducing the cost of carcinogenicity studies. A better understanding of the advantages and disadvantages of the transgenic rasH2 mouse will result in greater and more efficient use of this animal model in the future.

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

NCI Mouse Repository | Frederick National Laboratory for Cancer Research

Cancer.gov

The NCI Mouse Repository is an NCI-funded resource for mouse cancer models and associated strains. The repository makes strains available to all members of the scientific community (academic, non-profit, and commercial). NCI Mouse Repository strains

Cerebellar Development and Disease

PubMed Central

Gleeson, Joseph G.

2008-01-01

Recent Advances The molecular control of cell type specification within the developing cerebellum as well as the genetic causes of the most common human developmental cerebellar disorders have long remained mysterious. Recent genetic lineage and loss-of-function data from mice have revealed unique and non-overlapping anatomical origins for GABAergic neurons from ventricular zone precursors and glutamatergic cell from rhombic lip precursors, mirroring distinct origins for these neurotransmitter-specific cell types in the cerebral cortex. Mouse studies elucidating the role of Ptf1a as a cerebellar ventricular zone GABerigic fate switch were actually preceded by the recognition that PTF1A mutations in humans cause cerebellar agenesis, a birth defect of the human cerebellum. Indeed, several genes for congenital human cerebellar malformations have recently been identified, including genes causing Joubert syndrome, Dandy-Walker malformation and Ponto-cerebellar hypoplasia. These studies have pointed to surprisingly complex roles for transcriptional regulation, mitochondrial function and neuronal cilia in patterning, homeostasis and cell proliferation during cerebellar development. Together mouse and human studies are synergistically advancing our understanding of the developmental mechanisms that generate the uniquely complex mature cerebellum. PMID:18513948

Conserved and divergent functions of Pax6 underlie species-specific neurogenic patterns in the developing amniote brain.

PubMed

Yamashita, Wataru; Takahashi, Masanori; Kikkawa, Takako; Gotoh, Hitoshi; Osumi, Noriko; Ono, Katsuhiko; Nomura, Tadashi

2018-04-16

The evolution of unique organ structures is associated with changes in conserved developmental programs. However, characterizing the functional conservation and variation of homologous transcription factors (TFs) that dictate species-specific cellular dynamics has remained elusive. Here, we dissect shared and divergent functions of Pax6 during amniote brain development. Comparative functional analyses revealed that the neurogenic function of Pax6 is highly conserved in the developing mouse and chick pallium, whereas stage-specific binary functions of Pax6 in neurogenesis are unique to mouse neuronal progenitors, consistent with Pax6-dependent temporal regulation of Notch signaling. Furthermore, we identified that Pax6-dependent enhancer activity of Dbx1 is extensively conserved between mammals and chick, although Dbx1 expression in the developing pallium is highly divergent in these species. Our results suggest that spatiotemporal changes in Pax6-dependent regulatory programs contributed to species-specific neurogenic patterns in mammalian and avian lineages, which underlie the morphological divergence of the amniote pallial architectures. © 2018. Published by The Company of Biologists Ltd.

Identification of hamster inducible nitric oxide synthase (iNOS) promoter sequences that influence basal and inducible iNOS expression

PubMed Central

Saldarriaga, Omar A.; Travi, Bruno L.; Choudhury, Goutam Ghosh; Melby, Peter C.

2012-01-01

IFN-γ/LPS-activated hamster (Mesocricetus auratus) macrophages express significantly less iNOS (NOS2) than activated mouse macrophages, which contributes to the hamster's susceptibility to intracellular pathogens. We determined a mechanism responsible for differences in iNOS promoter activity in hamsters and mice. The HtPP (1.2 kb) showed low basal and inducible promoter activity when compared with the mouse, and sequences within a 100-bp region (−233 to −133) of the mouse and hamster promoters influenced this activity. Moreover, within this 100 bp, we identified a smaller region (44 bp) in the mouse promoter, which recovered basal promoter activity when swapped into the hamster promoter. The mouse homolog (100-bp region) contained a cis-element for NF-IL-6 (−153/−142), which was absent in the hamster counterpart. EMSA and supershift assays revealed that the hamster sequence did not support the binding of NF-IL-6. Introduction of a functional NF-IL-6 binding sequence into the hamster promoter or its alteration in the mouse promoter revealed the critical importance of this transcription factor for full iNOS promoter activity. Furthermore, the binding of NF-IL-6 to the iNOS promoter (−153/−142) in vivo was increased in mouse cells but was reduced in hamster cells after IFN-γ/LPS stimulation. Differences in the activity of the iNOS promoters were evident in mouse and hamster cells, so they were not merely a result of species-specific differences in transcription factors. Thus, we have identified unique DNA sequences and a critical transcription factor, NF-IL-6, which contribute to the overall basal and inducible expression of hamster iNOS. PMID:22517919

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.

Generation of a neuro-specific microarray reveals novel differentially expressed noncoding RNAs in mouse models for neurodegenerative diseases.

PubMed

Gstir, Ronald; Schafferer, Simon; Scheideler, Marcel; Misslinger, Matthias; Griehl, Matthias; Daschil, Nina; Humpel, Christian; Obermair, Gerald J; Schmuckermair, Claudia; Striessnig, Joerg; Flucher, Bernhard E; Hüttenhofer, Alexander

2014-12-01

We have generated a novel, neuro-specific ncRNA microarray, covering 1472 ncRNA species, to investigate their expression in different mouse models for central nervous system diseases. Thereby, we analyzed ncRNA expression in two mouse models with impaired calcium channel activity, implicated in Epilepsy or Parkinson's disease, respectively, as well as in a mouse model mimicking pathophysiological aspects of Alzheimer's disease. We identified well over a hundred differentially expressed ncRNAs, either from known classes of ncRNAs, such as miRNAs or snoRNAs or which represented entirely novel ncRNA species. Several differentially expressed ncRNAs in the calcium channel mouse models were assigned as miRNAs and target genes involved in calcium signaling, thus suggesting feedback regulation of miRNAs by calcium signaling. In the Alzheimer mouse model, we identified two snoRNAs, whose expression was deregulated prior to amyloid plaque formation. Interestingly, the presence of snoRNAs could be detected in cerebral spine fluid samples in humans, thus potentially serving as early diagnostic markers for Alzheimer's disease. In addition to known ncRNAs species, we also identified 63 differentially expressed, entirely novel ncRNA candidates, located in intronic or intergenic regions of the mouse genome, genomic locations, which previously have been shown to harbor the majority of functional ncRNAs. © 2014 Gstir et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

PDX-1 Is a Therapeutic Target for Pancreatic Cancer, Insulinoma and Islet Neoplasia Using a Novel RNA Interference Platform

PubMed Central

Liu, Shi-He; Rao, Donald D.; Nemunaitis, John; Senzer, Neil; Zhou, Guisheng; Dawson, David; Gingras, Marie-Claude; Wang, Zhaohui; Gibbs, Richard; Norman, Michael; Templeton, Nancy S.; DeMayo, Francesco J.; O'Malley, Bert; Sanchez, Robbi; Fisher, William E.; Brunicardi, F. Charles

2012-01-01

Pancreatic and duodenal homeobox-1 (PDX-1) is a transcription factor that regulates insulin expression and islet maintenance in the adult pancreas. Our recent studies demonstrate that PDX-1 is an oncogene for pancreatic cancer and is overexpressed in pancreatic cancer. The purpose of this study was to demonstrate that PDX-1 is a therapeutic target for both hormonal symptoms and tumor volume in mouse models of pancreatic cancer, insulinoma and islet neoplasia. Immunohistochemistry of human pancreatic and islet neoplasia specimens revealed marked PDX-1 overexpression, suggesting PDX-1 as a “drugable” target within these diseases. To do so, a novel RNA interference effector platform, bifunctional shRNAPDX-1, was developed and studied in mouse and human cell lines as well as in mouse models of pancreatic cancer, insulinoma and islet neoplasia. Systemic delivery of bi-shRNAhumanPDX-1 lipoplexes resulted in marked reduction of tumor volume and improved survival in a human pancreatic cancer xenograft mouse model. bi-shRNAmousePDX-1 lipoplexes prevented death from hyperinsulinemia and hypoglycemia in an insulinoma mouse model. shRNAmousePDX-1 lipoplexes reversed hyperinsulinemia and hypoglycemia in an immune-competent mouse model of islet neoplasia. PDX-1 was overexpressed in pancreatic neuroendocrine tumors and nesidioblastosis. These data demonstrate that PDX-1 RNAi therapy controls hormonal symptoms and tumor volume in mouse models of pancreatic cancer, insulinoma and islet neoplasia, therefore, PDX-1 is a potential therapeutic target for these pancreatic diseases. PMID:22905092

Development and Characterization of a Mouse Model for Marburg Hemorrhagic Fever

DTIC Science & Technology

2009-07-01

Microbiology. All Rights Reserved. Development and Characterization of a Mouse Model for Marburg Hemorrhagic Fever Kelly L. Warfield,* Steven B...mouse model has hampered an understanding of the pathogenesis and immunity of Marburg hemorrhagic fever (MHF), the disease caused by marburgvirus (MARV...cause severe hemorrhagic fevers in humans and non- human primates (27). The incubation time is estimated to be 3 to 21 days, with human case fatality

Producing a Mouse Model to Explore the Linkages Between Tocopherol Biology and Prostate Cancer

DTIC Science & Technology

2005-07-01

Edwards, Prostate cancer and supplementation with alpha-tocopherol and beta -carotene: incidence and mortality in a controlled trial. J Natl Cancer ...1-0153 TITLE: Producing a Mouse Model to Explore the Linkages Between Tocopherol Biology and Prostate Cancer ...TITLE AND SUBTITLE Producing a Mouse Model to Explore the Linkages Between Tocopherol 5a. CONTRACT NUMBER Biology and Prostate Cancer 5b. GRANT

Synergistic Action of FOXP3 and TSC1 Pathways During Tumor Progression

DTIC Science & Technology

2015-10-01

invasive carcinoma and, ultimately, metastatic disease [1-3]. Mouse models of PIN (mPIN) generated by a single- mutant gene in prostate do not progress...downstream target) is sufficient to significantly reduce the initiation of prostate cancer in the Pten conditional knockout mouse model [19-21...the possibility that these two genetic hits cooperate to promote tumor progression, and mouse models show that this cooperation accelerates

Designing Mouse Behavioral Tasks Relevant to Autistic-Like Behaviors

ERIC Educational Resources Information Center

Crawley, Jacqueline N.

2004-01-01

The importance of genetic factors in autism has prompted the development of mutant mouse models to advance our understanding of biological mechanisms underlying autistic behaviors. Mouse models of human neuropsychiatric diseases are designed to optimize (1) face validity, i.e., resemblance to the human symptoms; (2) construct validity, i.e.,…

Deregulation of the lysyl hydroxylase matrix cross-linking system in experimental and clinical bronchopulmonary dysplasia.

PubMed

Witsch, Thilo J; Turowski, Pawel; Sakkas, Elpidoforos; Niess, Gero; Becker, Simone; Herold, Susanne; Mayer, Konstantin; Vadász, István; Roberts, Jesse D; Seeger, Werner; Morty, Rory E

2014-02-01

Bronchopulmonary dysplasia (BPD) is a common and serious complication of premature birth, characterized by a pronounced arrest of alveolar development. The underlying pathophysiological mechanisms are poorly understood although perturbations to the maturation and remodeling of the extracellular matrix (ECM) are emerging as candidate disease pathomechanisms. In this study, the expression and regulation of three members of the lysyl hydroxylase family of ECM remodeling enzymes (Plod1, Plod2, and Plod3) in clinical BPD, as well as in an experimental animal model of BPD, were addressed. All three enzymes were localized to the septal walls in developing mouse lungs, with Plod1 also expressed in the vessel walls of the developing lung and Plod3 expressed uniquely at the base of developing septa. The expression of plod1, plod2, and plod3 was upregulated in the lungs of mouse pups exposed to 85% O2, an experimental animal model of BPD. Transforming growth factor (TGF)-β increased plod2 mRNA levels and activated the plod2 promoter in vitro in lung epithelial cells and in lung fibroblasts. Using in vivo neutralization of TGF-β signaling in the experimental animal model of BPD, TGF-β was identified as the regulator of aberrant plod2 expression. PLOD2 mRNA expression was also elevated in human neonates who died with BPD or at risk for BPD, compared with neonates matched for gestational age at birth or chronological age at death. These data point to potential roles for lysyl hydroxylases in normal lung development, as well as in perturbed late lung development associated with BPD.

Use of a leukocyte-targeted peptide probe as a potential tracer for imaging the tuberculosis granuloma.

PubMed

Locke, Landon W; Kothandaraman, Shankaran; Tweedle, Michael; Chaney, Sarah; Wozniak, Daniel J; Schlesinger, Larry S

2018-01-01

Granulomas are the histopathologic hallmark of tuberculosis (TB), both in latency and active disease. Diagnostic and therapeutic strategies that specifically target granulomas have not been developed. Our objective is to develop a probe for imaging relevant immune cell populations infiltrating the granuloma. We report the binding specificity of Cyanine 3 (Cy3)-labeled cFLFLFK-PEG 12 to human leukocytes and cellular constituents within a human in vitro granuloma model. We also report use of the probe in in vivo studies using a mouse model of lung granulomatous inflammation. We found that the probe preferentially binds human neutrophils and macrophages in human granuloma structures. Inhibition studies showed that peptide binding to human neutrophils is mediated by the receptor formyl peptide receptor 1 (FPR1). Imaging the distribution of intravenously administered cFLFLFK-PEG 12 -Cy3 in the mouse model revealed probe accumulation within granulomatous inflammatory responses in the lung. Further characterization revealed that the probe preferentially associated with neutrophils and cells of the monocyte/macrophage lineage. As there is no current clinical diagnostic imaging tool that specifically targets granulomas, the use of this probe in the context of latent and active TB may provide a unique advantage over current clinical imaging probes. We anticipate that utilizing a FPR1-targeted radiopharmaceutical analog of cFLFLFK in preclinical imaging studies may greatly contribute to our understanding of granuloma influx patterns and the biological roles and consequences of FPR1-expressing cells in contributing to disease pathogenesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

A test of current models for the mechanism of milk-lipid droplet secretion

PubMed Central

Jeong, Jaekwang; Lisinski, Ivonne; Kadegowda, Anil K.G.; Shin, Hyunsu; Wooding, F.B. Peter; Daniels, Brian R.; Schaack, Jerome; Mather, Ian H.

2013-01-01

Milk lipid is secreted by a unique process, during which triacylglycerol droplets bud from mammary cells coated with an outer bilayer of apical membrane. In all current schemes, the integral protein butyrophilin 1A1 (BTN) is postulated to serve as a transmembrane scaffold, which interacts, either with itself, or with the peripheral proteins, xanthine oxidoreductase (XOR) and possibly perilipin-2 (PLIN2), to form an immobile bridging complex between the droplet and apical surface. In one such scheme, BTN on the surface of cytoplasmic lipid droplets interacts directly with BTN in the apical membrane without binding to either XOR or PLIN2. We tested these models using both biochemical and morphological approaches. BTN was concentrated in the apical membrane in all species examined and contained mature N-linked glycans. We found no evidence for the association of unprocessed BTN with intracellular lipid droplets. BTN-enhanced-green-fluorescent-protein was highly mobile in areas of mouse milk-lipid droplets that had not undergone post-secretion changes, and endogenous mouse BTN comprised only 0.5–0.7%, (w/w) of the total protein, i.e., over fifty-fold less than in the milk-lipid droplets of cow and other species. These data are incompatible with models of milk-lipid secretion in which BTN is the major component of an immobile global adhesive complex and suggest that interactions between BTN and other proteins at the time of secretion are more transient than previously predicted. The high mobility of BTN in lipid droplets, mark it as a potential mobile signaling molecule in milk. PMID:23738536

Behavioral phenotypes of genetic mouse models of autism

PubMed Central

Kazdoba, T. M.; Leach, P. T.; Crawley, J. N.

2016-01-01

More than a hundred de novo single gene mutations and copy-number variants have been implicated in autism, each occurring in a small subset of cases. Mutant mouse models with syntenic mutations offer research tools to gain an understanding of the role of each gene in modulating biological and behavioral phenotypes relevant to autism. Knockout, knockin and transgenic mice incorporating risk gene mutations detected in autism spectrum disorder and comorbid neurodevelopmental disorders are now widely available. At present, autism spectrum disorder is diagnosed solely by behavioral criteria. We developed a constellation of mouse behavioral assays designed to maximize face validity to the types of social deficits and repetitive behaviors that are central to an autism diagnosis. Mouse behavioral assays for associated symptoms of autism, which include cognitive inflexibility, anxiety, hyperactivity, and unusual reactivity to sensory stimuli, are frequently included in the phenotypic analyses. Over the past 10 years, we and many other laboratories around the world have employed these and additional behavioral tests to phenotype a large number of mutant mouse models of autism. In this review, we highlight mouse models with mutations in genes that have been identified as risk genes for autism, which work through synaptic mechanisms and through the mTOR signaling pathway. Robust, replicated autism-relevant behavioral outcomes in a genetic mouse model lend credence to a causal role for specific gene contributions and downstream biological mechanisms in the etiology of autism. PMID:26403076

Mice with megabase humanization of their immunoglobulin genes generate antibodies as efficiently as normal mice.

PubMed

Murphy, Andrew J; Macdonald, Lynn E; Stevens, Sean; Karow, Margaret; Dore, Anthony T; Pobursky, Kevin; Huang, Tammy T; Poueymirou, William T; Esau, Lakeisha; Meola, Melissa; Mikulka, Warren; Krueger, Pamela; Fairhurst, Jeanette; Valenzuela, David M; Papadopoulos, Nicholas; Yancopoulos, George D

2014-04-08

Mice genetically engineered to be humanized for their Ig genes allow for human antibody responses within a mouse background (HumAb mice), providing a valuable platform for the generation of fully human therapeutic antibodies. Unfortunately, existing HumAb mice do not have fully functional immune systems, perhaps because of the manner in which their genetic humanization was carried out. Heretofore, HumAb mice have been generated by disrupting the endogenous mouse Ig genes and simultaneously introducing human Ig transgenes at a different and random location; KO-plus-transgenic humanization. As we describe in the companion paper, we attempted to make mice that more efficiently use human variable region segments in their humoral responses by precisely replacing 6 Mb of mouse Ig heavy and kappa light variable region germ-line gene segments with their human counterparts while leaving the mouse constant regions intact, using a unique in situ humanization approach. We reasoned the introduced human variable region gene segments would function indistinguishably in their new genetic location, whereas the retained mouse constant regions would allow for optimal interactions and selection of the resulting antibodies within the mouse environment. We show that these mice, termed VelocImmune mice because they were generated using VelociGene technology, efficiently produce human:mouse hybrid antibodies (that are rapidly convertible to fully human antibodies) and have fully functional humoral immune systems indistinguishable from those of WT mice. The efficiency of the VelocImmune approach is confirmed by the rapid progression of 10 different fully human antibodies into human clinical trials.

Human and mouse eLOX3 have distinct substrate specificities: implications for their linkage with lipoxygenases in skin

PubMed Central

Yu, Zheyong; Schneider, Claus; Boeglin, William E.; Brash, Alan R.

2008-01-01

Genetic and biochemical evidence suggests a functional link between human 12R-lipoxygenase (12R-LOX) and epidermal lipoxygenase-3 (eLOX3) in normal differentiation of the epidermis; LOX-derived fatty acid hydroperoxide is isomerized by the atypical eLOX3 into a specific epoxyalcohol that is a potential mediator in the pathway. Mouse epidermis expresses a different complement of LOX enzymes, and therefore this metabolic linkage could differ. To test this concept, we compared the substrate specificities of recombinant mouse and human eLOX3 toward sixteen hydroperoxy stereoisomers of arachidonic and linoleic acids. Both enzymes metabolized R-hydroperoxides 2–3 times faster than the corresponding S enantiomers. Whereas 12R-hydroperoxyeicosatetraenoic acid (12R-HPETE) is the best substrate for human eLOX3 (2.4 sec−1; at 30 µM substrate), mouse eLOX3 shows the highest turnover with 8R-HPETE (2.9 sec−1) followed by 8S-HPETE (1.3 sec−1). Novel product structures were characterized from reactions of mouse eLOX3 with 5S-, 8R-, and 8S-HPETEs. 8S-HPETE is converted specifically to a single epoxyalcohol, identified as 10R-hydroxy-8S,9S-epoxyeicosa-5Z,11Z,14Z-trienoic acid. The substrate preference of mouse eLOX3 and the unique occurrence of an 8S-LOX enzyme in mouse skin point to a potential LOX pathway for the production of epoxyalcohol in murine epidermal differentiation. PMID:17045234

Defining the role of polyamines in colon carcinogenesis using mouse models

PubMed Central

Ignatenko, Natalia A.; Gerner, Eugene W.; Besselsen, David G.

2011-01-01

Genetics and diet are both considered important risk determinants for colorectal cancer, a leading cause of death in the US and worldwide. Genetically engineered mouse (GEM) models have made a significant contribution to the characterization of colorectal cancer risk factors. Reliable, reproducible, and clinically relevant animal models help in the identification of the molecular events associated with disease progression and in the development of effictive treatment strategies. This review is focused on the use of mouse models for studying the role of polyamines in colon carcinogenesis. We describe how the available mouse models of colon cancer such as the multiple intestinal neoplasia (Min) mice and knockout genetic models facilitate understanding of the role of polyamines in colon carcinogenesis and help in the development of a rational strategy for colon cancer chemoprevention. PMID:21712957

Induction of a menopausal state alters the growth and histology of ovarian tumors in a mouse model of ovarian cancer.

PubMed

Laviolette, Laura A; Ethier, Jean-François; Senterman, Mary K; Devine, Patrick J; Vanderhyden, Barbara C

2011-05-01

Ovarian cancer is often diagnosed in women after menopause when the levels of the serum gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are increased because of the depletion of growing follicles within the ovary. The ability of FSH and LH to modulate the disease has not been well studied owing to a lack of physiologically relevant models of ovarian cancer. In this study, 4-vinylcyclohexene diepoxide (VCD) was used to deplete ovarian follicles and increase the levels of circulating FSH and LH in the tgCAG-LS-TAg mouse model of ovarian cancer. VCD-induced follicle depletion was performed either before or after induction of the oncogene SV40 large and small T-antigens in the ovarian surface epithelial cells of tgCAG-LS-TAg mice, which was mediated by the intrabursal delivery of an adenovirus expressing Cre recombinase (AdCre). tgCAG-LS-TAg mice injected with AdCre developed undifferentiated ovarian tumors with mixed epithelial and stromal components and some features of sex cord stromal tumors. Treatment with VCD before or after AdCre injection yielded tumors of similar histology, but with the unique appearance of Sertoli cell nests. In mice treated with VCD before the induction of tumorigenesis, the ovarian tumors tended to grow more slowly. The human ovarian cancer cell lines SKOV3 and OVCAR3 responded similarly to increased levels of gonadotropins in a second model of menopause, growing more slowly in ovariectomized mice compared with cycling controls. These results suggest that follicle depletion and increased gonadotropin levels can alter the histology and the rate of growth of ovarian tumors.

Clinically isolated enterovirus A71 subgenogroup C4 strain with lethal pathogenicity in 14-day-old mice and the application as an EV-A71 mouse infection model.

PubMed

Xu, Yi; Ma, Shuzhi; Zhu, Limeng; Huang, Zhiqiu; Chen, Liyun; Xu, Yuhua; Yin, Haibin; Peng, Tao; Wang, Yi

2017-01-01

The Enterovirus A71 (EV-A71) subgenogroup C4 is prevalent in China. EV-A71 causes hand, foot and mouth disease (HFMD) in children and may lead to severe neurological diseases. The development of antiviral and protective vaccines against EV-A71 is significantly hindered by the lack of suitable animal models to recapitulate human neurological symptoms. In this study, GZ-CII, a highly virulent EV-A71 subgenogroup C4 strain, was isolated from hospitalized children with HFMD. Intraperitoneal infections of GZ-CII resulted in progressive neurological disease in mice as old as 14 days. Administration of an inactivated EV-A71 vaccine or an anti-EV-A71 immune serum protected the mice against the GZ-CII infection. This demonstrated that a mouse model with EV-A71 GZ-CII could be used to evaluate potential vaccine candidates and therapeutics for subgenogroup C4. Comparing the genome sequence of GZ-CII with that of the avirulent EV-A71 subgenogroup C4 strain revealed unique mutations in GZ-CII. When mutation VP2-K149I was introduced into the nonpathogenic EV-A71 subgenogroup C4 strain, the variant similar to GZ-CII significantly increased viral replication and virulence in mice. These results indicated that the VP2-K149I mutation played an important role in enhancing the virulence of the EV-A71 subgenogroup C4 strain in mice, and that mice infected with the GZ-CII strain are a promising model for evaluating vaccines and therapeutics against the EV-A71 subgenogroup C4. Copyright © 2016 Elsevier B.V. All rights reserved.

Acquired MET expression confers resistance to EGFR inhibition in a mouse model of glioblastoma multiforme.

PubMed

Jun, H J; Acquaviva, J; Chi, D; Lessard, J; Zhu, H; Woolfenden, S; Bronson, R T; Pfannl, R; White, F; Housman, D E; Iyer, L; Whittaker, C A; Boskovitz, A; Raval, A; Charest, A

2012-06-21

Glioblastoma multiforme (GBM) is an aggressive brain tumor for which there is no cure. Overexpression of wild-type epidermal growth factor receptor (EGFR) and loss of the tumor suppressor genes Ink4a/Arf and PTEN are salient features of this deadly cancer. Surprisingly, targeted inhibition of EGFR has been clinically disappointing, demonstrating an innate ability for GBM to develop resistance. Efforts at modeling GBM in mice using wild-type EGFR have proven unsuccessful to date, hampering endeavors at understanding molecular mechanisms of therapeutic resistance. Here, we describe a unique genetically engineered mouse model of EGFR-driven gliomagenesis that uses a somatic conditional overexpression and chronic activation of wild-type EGFR in cooperation with deletions in the Ink4a/Arf and PTEN genes in adult brains. Using this model, we establish that chronic activation of wild-type EGFR with a ligand is necessary for generating tumors with histopathological and molecular characteristics of GBMs. We show that these GBMs are resistant to EGFR kinase inhibition and we define this resistance molecularly. Inhibition of EGFR kinase activity using tyrosine kinase inhibitors in GBM tumor cells generates a cytostatic response characterized by a cell cycle arrest, which is accompanied by a substantial change in global gene expression levels. We demonstrate that an important component of this pattern is the transcriptional activation of the MET receptor tyrosine kinase and that pharmacological inhibition of MET overcomes the resistance to EGFR inhibition in these cells. These findings provide important new insights into mechanisms of resistance to EGFR inhibition and suggest that inhibition of multiple targets will be necessary to provide therapeutic benefit for GBM patients.

High milk consumption does not affect prostate tumor progression in two mouse models of benign and neoplastic lesions.

PubMed

Bernichtein, Sophie; Pigat, Natascha; Capiod, Thierry; Boutillon, Florence; Verkarre, Virginie; Camparo, Philippe; Viltard, Mélanie; Méjean, Arnaud; Oudard, Stéphane; Souberbielle, Jean-Claude; Friedlander, Gérard; Goffin, Vincent

2015-01-01

Epidemiological studies that have investigated whether dairy (mainly milk) diets are associated with prostate cancer risk have led to controversial conclusions. In addition, no existing study clearly evaluated the effects of dairy/milk diets on prostate tumor progression, which is clinically highly relevant in view of the millions of men presenting with prostate pathologies worldwide, including benign prostate hyperplasia (BPH) or high-grade prostatic intraepithelial neoplasia (HGPIN). We report here a unique interventional animal study to address this issue. We used two mouse models of fully penetrant genetically-induced prostate tumorigenesis that were investigated at the stages of benign hyperplasia (probasin-Prl mice, Pb-Prl) or pre-cancerous PIN lesions (KIMAP mice). Mice were fed high milk diets (skim or whole) for 15 to 27 weeks of time depending on the kinetics of prostate tumor development in each model. Prostate tumor progression was assessed by tissue histopathology examination, epithelial proliferation, stromal inflammation and fibrosis, tumor invasiveness potency and expression of various tumor markers relevant for each model (c-Fes, Gprc6a, activated Stat5 and p63). Our results show that high milk consumption (either skim or whole) did not promote progression of existing prostate tumors when assessed at early stages of tumorigenesis (hyperplasia and neoplasia). For some parameters, and depending on milk type, milk regimen could even exhibit slight protective effects towards prostate tumor progression by decreasing the expression of tumor-related markers like Ki-67 and Gprc6a. In conclusion, our study suggests that regular milk consumption should not be considered detrimental for patients presenting with early-stage prostate tumors.

A Novel Strategy for Development of Recombinant Antitoxin Therapeutics Tested in a Mouse Botulism Model

PubMed Central

Leysath, Clinton E.; Ofori, Kwasi; Baldwin, Karen; Feng, Xiaochuan; Bedenice, Daniela; Webb, Robert P.; Wright, Patrick M.; Smith, Leonard A.; Tzipori, Saul; Shoemaker, Charles B.

2012-01-01

Antitoxins are needed that can be produced economically with improved safety and shelf life compared to conventional antisera-based therapeutics. Here we report a practical strategy for development of simple antitoxin therapeutics with substantial advantages over currently available treatments. The therapeutic strategy employs a single recombinant ‘targeting agent’ that binds a toxin at two unique sites and a ‘clearing Ab’ that binds two epitopes present on each targeting agent. Co-administration of the targeting agent and the clearing Ab results in decoration of the toxin with up to four Abs to promote accelerated clearance. The therapeutic strategy was applied to two Botulinum neurotoxin (BoNT) serotypes and protected mice from lethality in two different intoxication models with an efficacy equivalent to conventional antitoxin serum. Targeting agents were a single recombinant protein consisting of a heterodimer of two camelid anti-BoNT heavy-chain-only Ab VH (VHH) binding domains and two E-tag epitopes. The clearing mAb was an anti-E-tag mAb. By comparing the in vivo efficacy of treatments that employed neutralizing vs. non-neutralizing agents or the presence vs. absence of clearing Ab permitted unprecedented insight into the roles of toxin neutralization and clearance in antitoxin efficacy. Surprisingly, when a post-intoxication treatment model was used, a toxin-neutralizing heterodimer agent fully protected mice from intoxication even in the absence of clearing Ab. Thus a single, easy-to-produce recombinant protein was as efficacious as polyclonal antiserum in a clinically-relevant mouse model of botulism. This strategy should have widespread application in antitoxin development and other therapies in which neutralization and/or accelerated clearance of a serum biomolecule can offer therapeutic benefit. PMID:22238680

A novel strategy for development of recombinant antitoxin therapeutics tested in a mouse botulism model.

PubMed

Mukherjee, Jean; Tremblay, Jacqueline M; Leysath, Clinton E; Ofori, Kwasi; Baldwin, Karen; Feng, Xiaochuan; Bedenice, Daniela; Webb, Robert P; Wright, Patrick M; Smith, Leonard A; Tzipori, Saul; Shoemaker, Charles B

2012-01-01

Antitoxins are needed that can be produced economically with improved safety and shelf life compared to conventional antisera-based therapeutics. Here we report a practical strategy for development of simple antitoxin therapeutics with substantial advantages over currently available treatments. The therapeutic strategy employs a single recombinant 'targeting agent' that binds a toxin at two unique sites and a 'clearing Ab' that binds two epitopes present on each targeting agent. Co-administration of the targeting agent and the clearing Ab results in decoration of the toxin with up to four Abs to promote accelerated clearance. The therapeutic strategy was applied to two Botulinum neurotoxin (BoNT) serotypes and protected mice from lethality in two different intoxication models with an efficacy equivalent to conventional antitoxin serum. Targeting agents were a single recombinant protein consisting of a heterodimer of two camelid anti-BoNT heavy-chain-only Ab V(H) (VHH) binding domains and two E-tag epitopes. The clearing mAb was an anti-E-tag mAb. By comparing the in vivo efficacy of treatments that employed neutralizing vs. non-neutralizing agents or the presence vs. absence of clearing Ab permitted unprecedented insight into the roles of toxin neutralization and clearance in antitoxin efficacy. Surprisingly, when a post-intoxication treatment model was used, a toxin-neutralizing heterodimer agent fully protected mice from intoxication even in the absence of clearing Ab. Thus a single, easy-to-produce recombinant protein was as efficacious as polyclonal antiserum in a clinically-relevant mouse model of botulism. This strategy should have widespread application in antitoxin development and other therapies in which neutralization and/or accelerated clearance of a serum biomolecule can offer therapeutic benefit.

Targeting Cancer Protein Profiles with Split-Enzyme Reporter Fragments to Achieve Chemical Resolution for Molecular Imaging

DTIC Science & Technology

2013-08-01

We next tested the utility of the construct to accumulate in tumors expressing EGFR using an orthotopic mouse model for brain tumors. Glioma cells...filament tumor marker, identified implanted cells within the orthotopic mouse model which were of human origin, i.e. Gli36Δ5 cells, and demonstrated that...forward into in vivo animal tumor model studies. • In vivo imaging of EGFR targeted-complex in orthotopic mouse model of brain tumor. • Ex vivo validation

Genetically engineered mouse models of melanoma.

PubMed

Pérez-Guijarro, Eva; Day, Chi-Ping; Merlino, Glenn; Zaidi, M Raza

2017-06-01

Melanoma is a complex disease that exhibits highly heterogeneous etiological, histopathological, and genetic features, as well as therapeutic responses. Genetically engineered mouse (GEM) models provide powerful tools to unravel the molecular mechanisms critical for melanoma development and drug resistance. Here, we expound briefly the basis of the mouse modeling design, the available technology for genetic engineering, and the aspects influencing the use of GEMs to model melanoma. Furthermore, we describe in detail the currently available GEM models of melanoma. Cancer 2017;123:2089-103. © 2017 American Cancer Society. © 2017 American Cancer Society.

CRISPR-Mediated Knockout of Cybb in NSG Mice Establishes a Model of Chronic Granulomatous Disease for Human Stem-Cell Gene Therapy Transplants.

PubMed

Sweeney, Colin L; Choi, Uimook; Liu, Chengyu; Koontz, Sherry; Ha, Seung-Kwon; Malech, Harry L

2017-07-01

Chronic granulomatous disease (CGD) is characterized by defects in the production of microbicidal reactive oxygen species (ROS) by phagocytes. Testing of gene and cell therapies for the treatment of CGD in human hematopoietic cells requires preclinical transplant models. The use of the lymphocyte-deficient NOD.Cg-Prkdc scid Il2rg tm1Wjl/ SzJ (NSG) mouse strain for human hematopoietic cell xenografts to test CGD therapies is complicated by the presence of functional mouse granulocytes capable of producing ROS for subsequent bacterial and fungal killing. To establish a phagocyte-defective mouse model of X-linked CGD (X-CGD) in NSG mice, clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 was utilized for targeted knockout of mouse Cybb on the X-chromosome by microinjection of NSG mouse zygotes with Cas9 mRNA and CRISPR single-guide RNA targeting Cybb exon 1 or exon 3. This resulted in a high incidence of indel formation at the CRISPR target site, with all mice exhibiting deletions in at least one Cybb allele based on sequence analysis of tail snip DNA. A female mouse heterozygous for a 235-bp deletion in Cybb exon 1 was bred to an NSG male to establish the X-CGD NSG mouse strain, NSG.Cybb[KO]. Resulting male offspring with the 235 bp deletion were found to be defective for production of ROS by neutrophils and other phagocytes, and demonstrated increased susceptibility to spontaneous bacterial and fungal infections with granulomatous inflammation. The establishment of the phagocyte-defective NSG.Cybb[KO] mouse model enables the in vivo assessment of gene and cell therapy strategies for treating CGD in human hematopoietic cell transplants without obfuscation by functional mouse phagocytes, and may also be useful for modeling other phagocyte disorders in humanized NSG mouse xenografts.

Genetically engineered mouse models of craniopharyngioma: an opportunity for therapy development and understanding of tumor biology.

PubMed

Apps, John Richard; Martinez-Barbera, Juan Pedro

2017-05-01

Adamantinomatous craniopharyngioma (ACP) is the commonest tumor of the sellar region in childhood. Two genetically engineered mouse models have been developed and are giving valuable insights into ACP biology. These models have identified novel pathways activated in tumors, revealed an important function of paracrine signalling and extended conventional theories about the role of organ-specific stem cells in tumorigenesis. In this review, we summarize these mouse models, what has been learnt, their limitations and open questions for future research. We then discussed how these mouse models may be used to test novel therapeutics against potentially targetable pathways recently identified in human ACP. © 2017 The Authors. Brain Pathology published by John Wiley & Sons Ltd on behalf of International Society of Neuropathology.

Compensatory Limb Use and Behavioral Assessment of Motor Skill Learning Following Sensorimotor Cortex Injury in a Mouse Model of Ischemic Stroke

PubMed Central

Kerr, Abigail L.; Tennant, Kelly A.

2014-01-01

Mouse models have become increasingly popular in the field of behavioral neuroscience, and specifically in studies of experimental stroke. As models advance, it is important to develop sensitive behavioral measures specific to the mouse. The present protocol describes a skilled motor task for use in mouse models of stroke. The Pasta Matrix Reaching Task functions as a versatile and sensitive behavioral assay that permits experimenters to collect accurate outcome data and manipulate limb use to mimic human clinical phenomena including compensatory strategies (i.e., learned non-use) and focused rehabilitative training. When combined with neuroanatomical tools, this task also permits researchers to explore the mechanisms that support behavioral recovery of function (or lack thereof) following stroke. The task is both simple and affordable to set up and conduct, offering a variety of training and testing options for numerous research questions concerning functional outcome following injury. Though the task has been applied to mouse models of stroke, it may also be beneficial in studies of functional outcome in other upper extremity injury models. PMID:25045916

A murine model of targeted infusion for intracranial tumors.

PubMed

Kim, Minhyung; Barone, Tara A; Fedtsova, Natalia; Gleiberman, Anatoli; Wilfong, Chandler D; Alosi, Julie A; Plunkett, Robert J; Gudkov, Andrei; Skitzki, Joseph J

2016-01-01

Historically, intra-arterial (IA) drug administration for malignant brain tumors including glioblastoma multiforme (GBM) was performed as an attempt to improve drug delivery. With the advent of percutaneous neuorovascular techniques and modern microcatheters, intracranial drug delivery is readily feasible; however, the question remains whether IA administration is safe and more effective compared to other delivery modalities such as intravenous (IV) or oral administrations. Preclinical large animal models allow for comparisons between treatment routes and to test novel agents, but can be expensive and difficult to generate large numbers and rapid results. Accordingly, we developed a murine model of IA drug delivery for GBM that is reproducible with clear readouts of tumor response and neurotoxicities. Herein, we describe a novel mouse model of IA drug delivery accessing the internal carotid artery to treat ipsilateral implanted GBM tumors that is consistent and reproducible with minimal experience. The intent of establishing this unique platform is to efficiently interrogate targeted anti-tumor agents that may be designed to take advantage of a directed, regional therapy approach for brain tumors.

In vivo mouse myocardial (31)P MRS using three-dimensional image-selected in vivo spectroscopy (3D ISIS): technical considerations and biochemical validations.

PubMed

Bakermans, Adrianus J; Abdurrachim, Desiree; van Nierop, Bastiaan J; Koeman, Anneke; van der Kroon, Inge; Baartscheer, Antonius; Schumacher, Cees A; Strijkers, Gustav J; Houten, Sander M; Zuurbier, Coert J; Nicolay, Klaas; Prompers, Jeanine J

2015-10-01

(31)P MRS provides a unique non-invasive window into myocardial energy homeostasis. Mouse models of cardiac disease are widely used in preclinical studies, but the application of (31)P MRS in the in vivo mouse heart has been limited. The small-sized, fast-beating mouse heart imposes challenges regarding localized signal acquisition devoid of contamination with signal originating from surrounding tissues. Here, we report the implementation and validation of three-dimensional image-selected in vivo spectroscopy (3D ISIS) for localized (31)P MRS of the in vivo mouse heart at 9.4 T. Cardiac (31)P MR spectra were acquired in vivo in healthy mice (n = 9) and in transverse aortic constricted (TAC) mice (n = 8) using respiratory-gated, cardiac-triggered 3D ISIS. Localization and potential signal contamination were assessed with (31)P MRS experiments in the anterior myocardial wall, liver, skeletal muscle and blood. For healthy hearts, results were validated against ex vivo biochemical assays. Effects of isoflurane anesthesia were assessed by measuring in vivo hemodynamics and blood gases. The myocardial energy status, assessed via the phosphocreatine (PCr) to adenosine 5'-triphosphate (ATP) ratio, was approximately 25% lower in TAC mice compared with controls (0.76 ± 0.13 versus 1.00 ± 0.15; P < 0.01). Localization with one-dimensional (1D) ISIS resulted in two-fold higher PCr/ATP ratios than measured with 3D ISIS, because of the high PCr levels of chest skeletal muscle that contaminate the 1D ISIS measurements. Ex vivo determinations of the myocardial PCr/ATP ratio (0.94 ± 0.24; n = 8) confirmed the in vivo observations in control mice. Heart rate (497 ± 76 beats/min), mean arterial pressure (90 ± 3.3 mmHg) and blood oxygen saturation (96.2 ± 0.6%) during the experimental conditions of in vivo (31)P MRS were within the normal physiological range. Our results show that respiratory-gated, cardiac-triggered 3D ISIS allows for non-invasive assessments of in vivo mouse myocardial energy homeostasis with (31)P MRS under physiological conditions. Copyright © 2015 John Wiley & Sons, Ltd.

A comparison of some organizational characteristics of the mouse central retina and the human macula.

PubMed

Volland, Stefanie; Esteve-Rudd, Julian; Hoo, Juyea; Yee, Claudine; Williams, David S

2015-01-01

Mouse models have greatly assisted our understanding of retinal degenerations. However, the mouse retina does not have a macula, leading to the question of whether the mouse is a relevant model for macular degeneration. In the present study, a quantitative comparison between the organization of the central mouse retina and the human macula was made, focusing on some structural characteristics that have been suggested to be important in predisposing the macula to stresses leading to degeneration: photoreceptor density, phagocytic load on the RPE, and the relative thinness of Bruch's membrane. Light and electron microscopy measurements from retinas of two strains of mice, together with published data on human retinas, were used for calculations and subsequent comparisons. As in the human retina, the central region of the mouse retina possesses a higher photoreceptor cell density and a thinner Bruch's membrane than in the periphery; however, the magnitudes of these periphery to center gradients are larger in the human. Of potentially greater relevance is the actual photoreceptor cell density, which is much greater in the mouse central retina than in the human macula, underlying a higher phagocytic load for the mouse RPE. Moreover, at eccentricities that correspond to the peripheral half of the human macula, the rod to cone ratio is similar between mouse and human. Hence, with respect to photoreceptor density and phagocytic load of the RPE, the central mouse retina models at least the more peripheral part of the macula, where macular degeneration is often first evident.

A Genetically Engineered Mouse Model of Neuroblastoma Driven by Mutated ALK and MYCN

DTIC Science & Technology

2014-09-01

AWARD NUMBER: W81XWH-13-1-0220 TITLE: A Genetically Engineered Mouse Model of Neuroblastoma ...CONTRACT NUMBER A Genetically Engineered Mouse Model of Neuroblastoma Driven by Mutated ALK and MYCN 5b. GRANT NUMBER W81XWH-13-1-0220 5c...common ALK mutations in neuroblastoma , F1174L and R1275Q. We have determined that in tumors cells expressing mutated ALK, different downstream

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

Behavioural phenotyping assays for mouse models of autism

PubMed Central

Silverman, Jill L.; Yang, Mu; Lord, Catherine; Crawley, Jacqueline N.

2011-01-01

Autism is a heterogeneous neurodevelopmental disorder of unknown aetiology that affects 1 in 100–150 individuals. Diagnosis is based on three categories of behavioural criteria: abnormal social interactions, communication deficits and repetitive behaviours. Strong evidence for a genetic basis has prompted the development of mouse models with targeted mutations in candidate genes for autism. As the diagnostic criteria for autism are behavioural, phenotyping these mouse models requires behavioural assays with high relevance to each category of the diagnostic symptoms. Behavioural neuroscientists are generating a comprehensive set of assays for social interaction, communication and repetitive behaviours to test hypotheses about the causes of austism. Robust phenotypes in mouse models hold great promise as translational tools for discovering effective treatments for components of autism spectrum disorders. PMID:20559336

3D Cryo-Imaging: A Very High-Resolution View of the Whole Mouse

PubMed Central

Roy, Debashish; Steyer, Grant J.; Gargesha, Madhusudhana; Stone, Meredith E.; Wilson, David L.

2009-01-01

We developed the Case Cryo-imaging system that provides information rich, very high-resolution, color brightfield, and molecular fluorescence images of a whole mouse using a section-and-image block-face imaging technology. The system consists of a mouse-sized, motorized cryo-microtome with special features for imaging, a modified, brightfield/ fluorescence microscope, and a robotic xyz imaging system positioner, all of which is fully automated by a control system. Using the robotic system, we acquired microscopic tiled images at a pixel size of 15.6 µm over the block face of a whole mouse sectioned at 40 µm, with a total data volume of 55 GB. Viewing 2D images at multiple resolutions, we identified small structures such as cardiac vessels, muscle layers, villi of the small intestine, the optic nerve, and layers of the eye. Cryo-imaging was also suitable for imaging embryo mutants in 3D. A mouse, in which enhanced green fluorescent protein was expressed under gamma actin promoter in smooth muscle cells, gave clear 3D views of smooth muscle in the urogenital and gastrointestinal tracts. With cryo-imaging, we could obtain 3D vasculature down to 10 µm, over very large regions of mouse brain. Software is fully automated with fully programmable imaging/sectioning protocols, email notifications, and automatic volume visualization. With a unique combination of field-of-view, depth of field, contrast, and resolution, the Case Cryo-imaging system fills the gap between whole animal in vivo imaging and histology. PMID:19248166

Characterization of motor units in behaving adult mice shows a wide primary range

PubMed Central

Ritter, Laura K.; Tresch, Matthew C.; Heckman, C. J.; Manuel, Marin

2014-01-01

The mouse is essential for genetic studies of motor function in both normal and pathological states. Thus it is important to consider whether the structure of motor output from the mouse is in fact analogous to that recorded in other animals. There is a striking difference in the basic electrical properties of mouse motoneurons compared with those in rats, cats, and humans. The firing evoked by injected currents produces a unique frequency-current (F-I) function that emphasizes recruitment of motor units at their maximum force. These F-I functions, however, were measured in anesthetized preparations that lacked two key components of normal synaptic input: high levels of synaptic noise and neuromodulatory inputs. Recent studies suggest that the alterations in the F-I function due to these two components are essential for recreating firing behavior of motor units in human subjects. In this study we provide the first data on firing patterns of motor units in the awake mouse, focusing on steady output in quiet stance. The resulting firing patterns did not match the predictions from the mouse F-I behaviors but instead revealed rate modulation across a remarkably wide range (10–60 Hz). The low end of the firing range may be due to changes in the F-I relation induced by synaptic noise and neuromodulatory inputs. The high end of the range may indicate that, unlike other species, quiet standing in the mouse involves recruitment of relatively fast-twitch motor units. PMID:24805075

Characterization of motor units in behaving adult mice shows a wide primary range.

PubMed

Ritter, Laura K; Tresch, Matthew C; Heckman, C J; Manuel, Marin; Tysseling, Vicki M

2014-08-01

The mouse is essential for genetic studies of motor function in both normal and pathological states. Thus it is important to consider whether the structure of motor output from the mouse is in fact analogous to that recorded in other animals. There is a striking difference in the basic electrical properties of mouse motoneurons compared with those in rats, cats, and humans. The firing evoked by injected currents produces a unique frequency-current (F-I) function that emphasizes recruitment of motor units at their maximum force. These F-I functions, however, were measured in anesthetized preparations that lacked two key components of normal synaptic input: high levels of synaptic noise and neuromodulatory inputs. Recent studies suggest that the alterations in the F-I function due to these two components are essential for recreating firing behavior of motor units in human subjects. In this study we provide the first data on firing patterns of motor units in the awake mouse, focusing on steady output in quiet stance. The resulting firing patterns did not match the predictions from the mouse F-I behaviors but instead revealed rate modulation across a remarkably wide range (10-60 Hz). The low end of the firing range may be due to changes in the F-I relation induced by synaptic noise and neuromodulatory inputs. The high end of the range may indicate that, unlike other species, quiet standing in the mouse involves recruitment of relatively fast-twitch motor units. Copyright © 2014 the American Physiological Society.

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

Mouse phenotyping.

PubMed

Fuchs, Helmut; Gailus-Durner, Valérie; Adler, Thure; Aguilar-Pimentel, Juan Antonio; Becker, Lore; Calzada-Wack, Julia; Da Silva-Buttkus, Patricia; Neff, Frauke; Götz, Alexander; Hans, Wolfgang; Hölter, Sabine M; Horsch, Marion; Kastenmüller, Gabi; Kemter, Elisabeth; Lengger, Christoph; Maier, Holger; Matloka, Mikolaj; Möller, Gabriele; Naton, Beatrix; Prehn, Cornelia; Puk, Oliver; Rácz, Ildikó; Rathkolb, Birgit; Römisch-Margl, Werner; Rozman, Jan; Wang-Sattler, Rui; Schrewe, Anja; Stöger, Claudia; Tost, Monica; Adamski, Jerzy; Aigner, Bernhard; Beckers, Johannes; Behrendt, Heidrun; Busch, Dirk H; Esposito, Irene; Graw, Jochen; Illig, Thomas; Ivandic, Boris; Klingenspor, Martin; Klopstock, Thomas; Kremmer, Elisabeth; Mempel, Martin; Neschen, Susanne; Ollert, Markus; Schulz, Holger; Suhre, Karsten; Wolf, Eckhard; Wurst, Wolfgang; Zimmer, Andreas; Hrabě de Angelis, Martin

2011-02-01

Model organisms like the mouse are important tools to learn more about gene function in man. Within the last 20 years many mutant mouse lines have been generated by different methods such as ENU mutagenesis, constitutive and conditional knock-out approaches, knock-down, introduction of human genes, and knock-in techniques, thus creating models which mimic human conditions. Due to pleiotropic effects, one gene may have different functions in different organ systems or time points during development. Therefore mutant mouse lines have to be phenotyped comprehensively in a highly standardized manner to enable the detection of phenotypes which might otherwise remain hidden. The German Mouse Clinic (GMC) has been established at the Helmholtz Zentrum München as a phenotyping platform with open access to the scientific community (www.mousclinic.de; [1]). The GMC is a member of the EUMODIC consortium which created the European standard workflow EMPReSSslim for the systemic phenotyping of mouse models (http://www.eumodic.org/[2]). Copyright © 2010 Elsevier Inc. All rights reserved.

Practical Murine Hematopathology: A Comparative Review and Implications for Research

PubMed Central

O'Connell, Karyn E; Mikkola, Amy M; Stepanek, Aaron M; Vernet, Andyna; Hall, Christopher D; Sun, Chia C; Yildirim, Eda; Staropoli, John F; Lee, Jeannie T; Brown, Diane E

2015-01-01

Hematologic parameters are important markers of disease in human and veterinary medicine. Biomedical research has benefited from mouse models that recapitulate such disease, thus expanding knowledge of pathogenetic mechanisms and investigative therapies that translate across species. Mice in health have many notable hematologic differences from humans and other veterinary species, including smaller erythrocytes, higher percentage of circulating reticulocytes or polychromasia, lower peripheral blood neutrophil and higher peripheral blood and bone marrow lymphocyte percentages, variable leukocyte morphologies, physiologic splenic hematopoiesis and iron storage, and more numerous and shorter-lived erythrocytes and platelets. For accurate and complete hematologic analyses of disease and response to investigative therapeutic interventions, these differences and the unique features of murine hematopathology must be understood. Here we review murine hematology and hematopathology for practical application to translational investigation. PMID:25926395

Associative DNA methylation changes in children with prenatal alcohol exposure.

PubMed

Laufer, Benjamin I; Kapalanga, Joachim; Castellani, Christina A; Diehl, Eric J; Yan, Liying; Singh, Shiva M

2015-01-01

Prenatal alcohol exposure (PAE) can cause fetal alcohol spectrum disorders (FASD). Previously, we assessed PAE in brain tissue from mouse models, however whether these changes are present in humans remains unknown. In this report, we show some identical changes in DNA methylation in the buccal swabs of six children with FASD using the 450K array. The changes occur in genes related to protocadherins, glutamatergic synapses, and hippo signaling. The results were found to be similar in another heterogeneous replication group of six FASD children. The replicated results suggest that children born with FASD have unique DNA methylation defects that can be influenced by sex and medication exposure. Ultimately, with future clinical development, assessment of DNA methylation from buccal swabs can provide a novel strategy for the diagnosis of FASD.

Tip-alpha (hp0596 gene product) is a highly immunogenic Helicobacter pylori protein involved in colonization of mouse gastric mucosa.

PubMed

Godlewska, Renata; Pawlowski, Marcin; Dzwonek, Artur; Mikula, Michal; Ostrowski, Jerzy; Drela, Nadzieja; Jagusztyn-Krynicka, Elzbieta K

2008-03-01

A product of the Helicobacter pylori hp0596 gene (Tip-alpha) is a highly immunogenic homodimeric protein, unique for this bacterium. Cell fractionation experiments indicate that Tip-alpha is anchored to the inner membrane. In contrast, the three-dimensional model of the protein suggests that Tip-alpha is soluble or, at least, largely exposed to the solvent. hp0596 gene knockout resulted in a significant decrease in the level of H. pylori colonization as measured by real-time PCR assay. In addition, the Tip-alpha recombinant protein was determined to stimulate macrophage to produce IL-1alpha and TNF-alpha. Both results imply that Tip-alpha is rather loosely connected to the inner membrane and potentially released during infection.

Cellular and molecular identity of tumor-associated macrophages in glioblastoma

PubMed Central

Chen, Zhihong; Feng, Xi; Herting, Cameron J.; Garcia, Virginia Alvarez; Nie, Kai; Pong, Winnie W.; Rasmussen, Rikke; Dwivedi, Bhakti; Seby, Sandra; Wolf, Susanne A.; Gutmann, David H.; Hambardzumyan, Dolores

2017-01-01

In glioblastoma (GBM), tumor-associated macrophages (TAM) represent up to one half of the cells of the tumor mass, including both infiltrating macrophages and resident brain microglia. In an effort to delineate the temporal and spatial dynamics of TAM composition during gliomagenesis, we employed two genetically engineered mouse models where oncogenic drivers and fluorescent reporters were expressed coordinately under the control of the monocyte/microglia-selective Cx3cr1 or Ccr2 promoters, respectively. Using this approach, we demonstrated that CX3CR1LoCCR2Hi monocytes were recruited to the glioblastoma, where they transitioned to CX3CR1HiCCR2Lo macrophages and CX3CR1HiCCR2− microglia-like cells. Infiltrating macrophages/monocytes constituted ~85% of the total TAM population, with resident microglia accounting for the ~15% remaining. Bone marrow-derived infiltrating macrophages/monocytes were recruited to the tumor early during GBM initiation, where they localized preferentially to perivascular areas. In contrast, resident microglia were localized mainly to peritumoral regions. RNA-sequencing analyses revealed differential gene expression patterns unique to infiltrating and resident cells, suggesting unique functions for each TAM population. Notably, limiting monocyte infiltration via Ccl2 genetic ablation prolonged the survival of tumor-bearing mice. Our findings illuminate the unique composition and functions of infiltrating and resident myeloid cells in GBM, establishing a rationale to target infiltrating cells in this neoplasm. PMID:28235764

Unique signatures of long noncoding RNA expression in response to virus infection and altered innate immune signaling.

PubMed

Peng, Xinxia; Gralinski, Lisa; Armour, Christopher D; Ferris, Martin T; Thomas, Matthew J; Proll, Sean; Bradel-Tretheway, Birgit G; Korth, Marcus J; Castle, John C; Biery, Matthew C; Bouzek, Heather K; Haynor, David R; Frieman, Matthew B; Heise, Mark; Raymond, Christopher K; Baric, Ralph S; Katze, Michael G

2010-10-26

Studies of the host response to virus infection typically focus on protein-coding genes. However, non-protein-coding RNAs (ncRNAs) are transcribed in mammalian cells, and the roles of many of these ncRNAs remain enigmas. Using next-generation sequencing, we performed a whole-transcriptome analysis of the host response to severe acute respiratory syndrome coronavirus (SARS-CoV) infection across four founder mouse strains of the Collaborative Cross. We observed differential expression of approximately 500 annotated, long ncRNAs and 1,000 nonannotated genomic regions during infection. Moreover, studies of a subset of these ncRNAs and genomic regions showed the following. (i) Most were similarly regulated in response to influenza virus infection. (ii) They had distinctive kinetic expression profiles in type I interferon receptor and STAT1 knockout mice during SARS-CoV infection, including unique signatures of ncRNA expression associated with lethal infection. (iii) Over 40% were similarly regulated in vitro in response to both influenza virus infection and interferon treatment. These findings represent the first discovery of the widespread differential expression of long ncRNAs in response to virus infection and suggest that ncRNAs are involved in regulating the host response, including innate immunity. At the same time, virus infection models provide a unique platform for studying the biology and regulation of ncRNAs.

Unique Signatures of Long Noncoding RNA Expression in Response to Virus Infection and Altered Innate Immune Signaling

PubMed Central

Peng, Xinxia; Gralinski, Lisa; Armour, Christopher D.; Ferris, Martin T.; Thomas, Matthew J.; Proll, Sean; Bradel-Tretheway, Birgit G.; Korth, Marcus J.; Castle, John C.; Biery, Matthew C.; Bouzek, Heather K.; Haynor, David R.; Frieman, Matthew B.; Heise, Mark; Raymond, Christopher K.; Baric, Ralph S.; Katze, Michael G.

2010-01-01

Studies of the host response to virus infection typically focus on protein-coding genes. However, non-protein-coding RNAs (ncRNAs) are transcribed in mammalian cells, and the roles of many of these ncRNAs remain enigmas. Using next-generation sequencing, we performed a whole-transcriptome analysis of the host response to severe acute respiratory syndrome coronavirus (SARS-CoV) infection across four founder mouse strains of the Collaborative Cross. We observed differential expression of approximately 500 annotated, long ncRNAs and 1,000 nonannotated genomic regions during infection. Moreover, studies of a subset of these ncRNAs and genomic regions showed the following. (i) Most were similarly regulated in response to influenza virus infection. (ii) They had distinctive kinetic expression profiles in type I interferon receptor and STAT1 knockout mice during SARS-CoV infection, including unique signatures of ncRNA expression associated with lethal infection. (iii) Over 40% were similarly regulated in vitro in response to both influenza virus infection and interferon treatment. These findings represent the first discovery of the widespread differential expression of long ncRNAs in response to virus infection and suggest that ncRNAs are involved in regulating the host response, including innate immunity. At the same time, virus infection models provide a unique platform for studying the biology and regulation of ncRNAs. PMID:20978541

Arrhenius analysis of the relationship between hyperthermia and Hsp70 promoter activation: a comparison between ex vivo and in vivo data.

PubMed

Deckers, Roel; Debeissat, Christelle; Fortin, Pierre-Yves; Moonen, Chrit T W; Couillaud, Franck

2012-01-01

Tight regulation of gene expression in the region where therapy is necessary and for the duration required to achieve a therapeutic effect and to minimise systemic toxicity is very important for clinical applications of gene therapy. Hyperthermia in combination with a temperature sensitive heat shock protein (Hsp70) promoter presents a unique approach allowing non-invasive spatio-temporal control of transgene expression. In this study we investigated the in vivo and ex vivo relationship between temperature and duration of thermal stress with respect to the resulting gene expression using an Arrhenius analysis. A transgenic mouse expressing the luciferase reporter gene under the transcriptional control of a thermosensitive promoter was used to assure identical genotype for in vivo (mouse leg) and ex vivo (bone marrow mononuclear and embryonic fibroblast cells) studies. The mouse leg and cells were heated at different temperatures and different exposure times. Bioluminescence imaging and in vitro enzymatic assay were used to measure the resulting transgene expression. We showed that temperature-induced Hsp70 promoter activation was modulated by both temperature as well as duration of hyperthermia. The relationship between temperature and duration of hyperthermia and the resulting reporter gene expression can be modelled by an Arrhenius analysis for both in vivo as well as ex vivo. However, the increase in reporter gene expression after elevating the temperature of the thermal stress with 1°C is not comparable for in vivo and ex vivo situations. This information may be valuable for optimising clinical gene therapy protocols.

GRP78 plays an essential role in adipogenesis and postnatal growth in mice

PubMed Central

Zhu, Genyuan; Ye, Risheng; Jung, Dae Young; Barron, Ernesto; Friedline, Randall H.; Benoit, Vivian M.; Hinton, David R.; Kim, Jason K.; Lee, Amy S.

2013-01-01

To investigate the role of GRP78 in adipogenesis and metabolic homeostasis, we knocked down GRP78 in mouse embryonic fibroblasts and 3T3-L1 preadipocytes induced to undergo differentiation into adipocytes. We also created an adipose Grp78-knockout mouse utilizing the aP2 (fatty acid binding protein 4) promoter-driven Cre-recombinase. Adipogenesis was monitored by molecular markers and histology. Tissues were analyzed by micro-CT and electron microscopy. Glucose homeostasis and cytokine analysis were performed. Our results indicate that GRP78 is essential for adipocyte differentiation in vitro. aP2-cre-mediated GRP78 deletion leads to lipoatrophy with ∼90% reduction in gonadal and subcutaneous white adipose tissue and brown adipose tissue, severe growth retardation, and bone defects. Despite severe abnormality in adipose mass and function, adipose Grp78-knockout mice showed normal plasma triglyceride levels, and plasma glucose and insulin levels were reduced by 40-60% compared to wild-type mice, suggesting enhanced insulin sensitivity. The endoplasmic reticulum is grossly expanded in the residual mutant white adipose tissue. Thus, these studies establish that GRP78 is required for adipocyte differentiation, glucose homeostasis, and balanced secretion of adipokines. Unexpectedly, the phenotypes and metabolic parameters of the mutant mice, which showed early postnatal mortality, are uniquely distinct from previously characterized lipodystrophic mouse models.—Zhu, G., Ye, R., Jung, D. Y., Barron, E., Friedline, R. H., Benoit, V. M., Hinton, D. R., Kim, J. K., Lee, A. S. GRP78 plays an essential role in adipogenesis and postnatal growth in mice. PMID:23180827

Voltage-sensitive rhodol with enhanced two-photon brightness

PubMed Central

Kulkarni, Rishikesh U.; Kramer, Daniel J.; Pourmandi, Narges; Karbasi, Kaveh; Bateup, Helen S.

2017-01-01

We have designed, synthesized, and applied a rhodol-based chromophore to a molecular wire-based platform for voltage sensing to achieve fast, sensitive, and bright voltage sensing using two-photon (2P) illumination. Rhodol VoltageFluor-5 (RVF5) is a voltage-sensitive dye with improved 2P cross-section for use in thick tissue or brain samples. RVF5 features a dichlororhodol core with pyrrolidyl substitution at the nitrogen center. In mammalian cells under one-photon (1P) illumination, RVF5 demonstrates high voltage sensitivity (28% ΔF/F per 100 mV) and improved photostability relative to first-generation voltage sensors. This photostability enables multisite optical recordings from neurons lacking tuberous sclerosis complex 1, Tsc1, in a mouse model of genetic epilepsy. Using RVF5, we show that Tsc1 KO neurons exhibit increased activity relative to wild-type neurons and additionally show that the proportion of active neurons in the network increases with the loss of Tsc1. The high photostability and voltage sensitivity of RVF5 is recapitulated under 2P illumination. Finally, the ability to chemically tune the 2P absorption profile through the use of rhodol scaffolds affords the unique opportunity to image neuronal voltage changes in acutely prepared mouse brain slices using 2P illumination. Stimulation of the mouse hippocampus evoked spiking activity that was readily discerned with bath-applied RVF5, demonstrating the utility of RVF5 and molecular wire-based voltage sensors with 2P-optimized fluorophores for imaging voltage in intact brain tissue. PMID:28242676

Efficient analysis of mouse genome sequences reveal many nonsense variants

PubMed Central

Steeland, Sophie; Timmermans, Steven; Van Ryckeghem, Sara; Hulpiau, Paco; Saeys, Yvan; Van Montagu, Marc; Vandenbroucke, Roosmarijn E.; Libert, Claude

2016-01-01

Genetic polymorphisms in coding genes play an important role when using mouse inbred strains as research models. They have been shown to influence research results, explain phenotypical differences between inbred strains, and increase the amount of interesting gene variants present in the many available inbred lines. SPRET/Ei is an inbred strain derived from Mus spretus that has ∼1% sequence difference with the C57BL/6J reference genome. We obtained a listing of all SNPs and insertions/deletions (indels) present in SPRET/Ei from the Mouse Genomes Project (Wellcome Trust Sanger Institute) and processed these data to obtain an overview of all transcripts having nonsynonymous coding sequence variants. We identified 8,883 unique variants affecting 10,096 different transcripts from 6,328 protein-coding genes, which is about 28% of all coding genes. Because only a subset of these variants results in drastic changes in proteins, we focused on variations that are nonsense mutations that ultimately resulted in a gain of a stop codon. These genes were identified by in silico changing the C57BL/6J coding sequences to the SPRET/Ei sequences, converting them to amino acid (AA) sequences, and comparing the AA sequences. All variants and transcripts affected were also stored in a database, which can be browsed using a SPRET/Ei M. spretus variants web tool (www.spretus.org), including a manual. We validated the tool by demonstrating the loss of function of three proteins predicted to be severely truncated, namely Fas, IRAK2, and IFNγR1. PMID:27147605

Human androgen deficiency: insights gained from androgen receptor knockout mouse models

PubMed Central

Rana, Kesha; Davey, Rachel A; Zajac, Jeffrey D

2014-01-01

The mechanism of androgen action is complex. Recently, significant advances have been made into our understanding of how androgens act via the androgen receptor (AR) through the use of genetically modified mouse models. A number of global and tissue-specific AR knockout (ARKO) models have been generated using the Cre-loxP system which allows tissue- and/or cell-specific deletion. These ARKO models have examined a number of sites of androgen action including the cardiovascular system, the immune and hemopoetic system, bone, muscle, adipose tissue, the prostate and the brain. This review focuses on the insights that have been gained into human androgen deficiency through the use of ARKO mouse models at each of these sites of action, and highlights the strengths and limitations of these Cre-loxP mouse models that should be considered to ensure accurate interpretation of the phenotype. PMID:24480924

Modelling clinical systemic lupus erythematosus: similarities, differences and success stories

PubMed Central

Celhar, Teja

2017-01-01

Abstract Mouse models of SLE have been indispensable tools to study disease pathogenesis, to identify genetic susceptibility loci and targets for drug development, and for preclinical testing of novel therapeutics. Recent insights into immunological mechanisms of disease progression have boosted a revival in SLE drug development. Despite promising results in mouse studies, many novel drugs have failed to meet clinical end points. This is probably because of the complexity of the disease, which is driven by polygenic predisposition and diverse environmental factors, resulting in a heterogeneous clinical presentation. Each mouse model recapitulates limited aspects of lupus, especially in terms of the mechanism underlying disease progression. The main mouse models have been fairly successful for the evaluation of broad-acting immunosuppressants. However, the advent of targeted therapeutics calls for a selection of the most appropriate model(s) for testing and, ultimately, identification of patients who will be most likely to respond. PMID:28013204

Mouse Models of Gastric Cancer

PubMed Central

Hayakawa, Yoku; Fox, James G.; Gonda, Tamas; Worthley, Daniel L.; Muthupalani, Sureshkumar; Wang, Timothy C.

2013-01-01

Animal models have greatly enriched our understanding of the molecular mechanisms of numerous types of cancers. Gastric cancer is one of the most common cancers worldwide, with a poor prognosis and high incidence of drug-resistance. However, most inbred strains of mice have proven resistant to gastric carcinogenesis. To establish useful models which mimic human gastric cancer phenotypes, investigators have utilized animals infected with Helicobacter species and treated with carcinogens. In addition, by exploiting genetic engineering, a variety of transgenic and knockout mouse models of gastric cancer have emerged, such as INS-GAS mice and TFF1 knockout mice. Investigators have used the combination of carcinogens and gene alteration to accelerate gastric cancer development, but rarely do mouse models show an aggressive and metastatic gastric cancer phenotype that could be relevant to preclinical studies, which may require more specific targeting of gastric progenitor cells. Here, we review current gastric carcinogenesis mouse models and provide our future perspectives on this field. PMID:24216700

Phenotyping male infertility in the mouse: how to get the most out of a 'non-performer'.

PubMed

Borg, Claire L; Wolski, Katja M; Gibbs, Gerard M; O'Bryan, Moira K

2010-01-01

Functional male gametes are produced through complex processes that take place within the testis, epididymis and female reproductive tract. A breakdown at any of these phases can result in male infertility. The production of mutant mouse models often yields an unexpected male infertility phenotype. It is with this in mind that the current review has been written. The review aims to act as a guide to the 'non-reproductive biologist' to facilitate a systematic analysis of sterile or subfertile mice and to assist in extracting the maximum amount of information from each model. This is a review of the original literature on defects in the processes that take a mouse spermatogonial stem cell through to a fully functional spermatozoon, which result in male infertility. Based on literature searches and personal experience, we have outlined a step-by-step strategy for the analysis of an infertile male mouse line. A wide range of methods can be used to define the phenotype of an infertile male mouse. These methods range from histological methods such as electron microscopy and immunohistochemistry, to hormone analyses and methods to assess sperm maturation status and functional competence. With the increased rate of genetically modified mouse production, the generation of mouse models with unexpected male infertility is increasing. This manuscript will help to ensure that the maximum amount of information is obtained from each mouse model and, by extension, will facilitate the knowledge of both normal fertility processes and the causes of human infertility.

A surgical approach appropriate for targeted cochlear gene therapy in the mouse.

PubMed

Jero, J; Tseng, C J; Mhatre, A N; Lalwani, A K

2001-01-01

Therapeutic manipulations of the mammalian cochlea, including cochlear gene transfer, have been predominantly studied using the guinea pig as the experimental model. With the significant developments in mouse genomics and the availability of mutant strains of mice with well-characterized hearing loss, the mouse justifiably will be the preferred animal model for therapeutic manipulations. However, the potential advantages of the mouse model have not been fully realized due to the surgical difficulty of accessing its small cochlea. This study describes a ventral approach, instead of the routinely used postauricular approach in other rodents, for accessing the mouse middle and inner ear, and its application in cochlear gene transfer. This ventral approach enabled rapid and direct delivery of liposome-transgene complex to the mouse inner ear while avoiding blood loss, facial nerve morbidity, and mortality. Transgene expression at 3 days was detected in Reissner's membrane, spiral limbus, spiral ligament, and spiral ganglion cells, in a pattern similar to that previously described in the guinea pig. The successful access and delivery of material to the mouse cochlea and the replication of gene expression seen in the guinea pig demonstrated in this study should promote the use of the mouse in future studies investigating targeted cochlear therapy.

Muscle-specific androgen receptor deletion shows limited actions in myoblasts but not in myofibers in different muscles in vivo.

PubMed

Rana, Kesha; Chiu, Maria W S; Russell, Patricia K; Skinner, Jarrod P; Lee, Nicole K L; Fam, Barbara C; Zajac, Jeffrey D; MacLean, Helen E

2016-08-01

The aim of this study was to investigate the direct muscle cell-mediated actions of androgens by comparing two different mouse lines. The cre-loxP system was used to delete the DNA-binding activity of the androgen receptor (AR) in mature myofibers (MCK mAR(ΔZF2)) in one model and the DNA-binding activity of the AR in both proliferating myoblasts and myofibers (α-actin mAR(ΔZF2)) in another model. We found that hind-limb muscle mass was normal in MCK mAR(ΔZF2) mice and that relative mass of only some hind-limb muscles was reduced in α-actin mAR(ΔZF2) mice. This suggests that myoblasts and myofibers are not the major cellular targets mediating the anabolic actions of androgens on male muscle during growth and development. Levator ani muscle mass was decreased in both mouse lines, demonstrating that there is a myofiber-specific effect in this unique androgen-dependent muscle. We found that the pattern of expression of genes including c-myc, Fzd4 and Igf2 is associated with androgen-dependent changes in muscle mass; therefore, these genes are likely to be mediators of anabolic actions of androgens. Further research is required to identify the major targets of androgen actions in muscle, which are likely to include indirect actions via other tissues. © 2016 Society for Endocrinology.

The influence of TRP53 in the dose response of radiation-induced apoptosis, DNA repair and genomic stability in murine haematopoietic cells

DOE PAGES

Lemon, Jennifer A.; Taylor, Kristina; Verdecchia, Kyle; ...

2014-01-01

Apoptotic and DNA damage endpoints are frequently used as surrogate markers of cancer risk, and have been well-studied in the Trp53+/- mouse model. We report the effect of differing Trp53 gene status on the dose response of ionizing radiation exposures (0.01-2 Gy), with the unique perspective of determining if effects of gene status remain at extended time points. Here we report no difference in the dose response for radiation-induced DNA double-strand breaks in bone marrow and genomic instability (MN-RET levels) in peripheral blood, between wild-type ( Trp53+/+) and heterozygous ( Trp53+/-) mice. The dose response for Trp53+/+ mice showed highermore » initial levels of radiation-induced lymphocyte apoptosis relative to Trp53+/- between 0 and 1 Gy. Although this trend was observed up to 12 hours post-irradiation, both genotypes ultimately reached the same level of apoptosis at 14 hours, suggesting the importance of late-onset p53-independent apoptotic responses in this mouse model. Expected radiation-induced G1 cell cycle delay was observed in Trp53+/+ but not Trp53+/-. Although p53 has an important role in cancer risk, we have shown its influence on radiation dose response can be temporally variable. This research highlights the importance of caution when using haematopoietic endpoints as surrogates to extrapolate radiation-induced cancer risk estimation.« less

Fragile X Mental Retardation Protein (FMRP) controls diacylglycerol kinase activity in neurons.

PubMed

Tabet, Ricardos; Moutin, Enora; Becker, Jérôme A J; Heintz, Dimitri; Fouillen, Laetitia; Flatter, Eric; Krężel, Wojciech; Alunni, Violaine; Koebel, Pascale; Dembélé, Doulaye; Tassone, Flora; Bardoni, Barbara; Mandel, Jean-Louis; Vitale, Nicolas; Muller, Dominique; Le Merrer, Julie; Moine, Hervé

2016-06-28

Fragile X syndrome (FXS) is caused by the absence of the Fragile X Mental Retardation Protein (FMRP) in neurons. In the mouse, the lack of FMRP is associated with an excessive translation of hundreds of neuronal proteins, notably including postsynaptic proteins. This local protein synthesis deregulation is proposed to underlie the observed defects of glutamatergic synapse maturation and function and to affect preferentially the hundreds of mRNA species that were reported to bind to FMRP. How FMRP impacts synaptic protein translation and which mRNAs are most important for the pathology remain unclear. Here we show by cross-linking immunoprecipitation in cortical neurons that FMRP is mostly associated with one unique mRNA: diacylglycerol kinase kappa (Dgkκ), a master regulator that controls the switch between diacylglycerol and phosphatidic acid signaling pathways. The absence of FMRP in neurons abolishes group 1 metabotropic glutamate receptor-dependent DGK activity combined with a loss of Dgkκ expression. The reduction of Dgkκ in neurons is sufficient to cause dendritic spine abnormalities, synaptic plasticity alterations, and behavior disorders similar to those observed in the FXS mouse model. Overexpression of Dgkκ in neurons is able to rescue the dendritic spine defects of the Fragile X Mental Retardation 1 gene KO neurons. Together, these data suggest that Dgkκ deregulation contributes to FXS pathology and support a model where FMRP, by controlling the translation of Dgkκ, indirectly controls synaptic proteins translation and membrane properties by impacting lipid signaling in dendritic spine.

The Rachitic Tooth

PubMed Central

Nociti, Francisco H.; Somerman, Martha J.

2014-01-01

Teeth are mineralized organs composed of three unique hard tissues, enamel, dentin, and cementum, and supported by the surrounding alveolar bone. Although odontogenesis differs from osteogenesis in several respects, tooth mineralization is susceptible to similar developmental failures as bone. Here we discuss conditions fitting under the umbrella of rickets, which traditionally referred to skeletal disease associated with vitamin D deficiency but has been more recently expanded to include newly identified factors involved in endocrine regulation of vitamin D, phosphate, and calcium, including phosphate-regulating endopeptidase homolog, X-linked, fibroblast growth factor 23, and dentin matrix protein 1. Systemic mineral metabolism intersects with local regulation of mineralization, and factors including tissue nonspecific alkaline phosphatase are necessary for proper mineralization, where rickets can result from loss of activity of tissue nonspecific alkaline phosphatase. Individuals suffering from rickets often bear the additional burden of a defective dentition, and transgenic mouse models have aided in understanding the nature and mechanisms involved in tooth defects, which may or may not parallel rachitic bone defects. This report reviews dental effects of the range of rachitic disorders, including discussion of etiologies of hereditary forms of rickets, a survey of resulting bone and tooth mineralization disorders, and a discussion of mechanisms, known and hypothesized, involved in the observed dental pathologies. Descriptions of human pathology are augmented by analysis of transgenic mouse models, and new interpretations are brought to bear on questions of how teeth are affected under conditions of rickets. In short, the rachitic tooth will be revealed. PMID:23939820

Behavioral phenotypes of genetic mouse models of autism.

PubMed

Kazdoba, T M; Leach, P T; Crawley, J N

2016-01-01

More than a hundred de novo single gene mutations and copy-number variants have been implicated in autism, each occurring in a small subset of cases. Mutant mouse models with syntenic mutations offer research tools to gain an understanding of the role of each gene in modulating biological and behavioral phenotypes relevant to autism. Knockout, knockin and transgenic mice incorporating risk gene mutations detected in autism spectrum disorder and comorbid neurodevelopmental disorders are now widely available. At present, autism spectrum disorder is diagnosed solely by behavioral criteria. We developed a constellation of mouse behavioral assays designed to maximize face validity to the types of social deficits and repetitive behaviors that are central to an autism diagnosis. Mouse behavioral assays for associated symptoms of autism, which include cognitive inflexibility, anxiety, hyperactivity, and unusual reactivity to sensory stimuli, are frequently included in the phenotypic analyses. Over the past 10 years, we and many other laboratories around the world have employed these and additional behavioral tests to phenotype a large number of mutant mouse models of autism. In this review, we highlight mouse models with mutations in genes that have been identified as risk genes for autism, which work through synaptic mechanisms and through the mTOR signaling pathway. Robust, replicated autism-relevant behavioral outcomes in a genetic mouse model lend credence to a causal role for specific gene contributions and downstream biological mechanisms in the etiology of autism. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

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

Neurocognitive endophenotypes in CGG KI and Fmr1 KO mouse models of Fragile X-Associated disorders: an analysis of the state of the field

PubMed Central

Hunsaker, Michael R.

2013-01-01

It has become increasingly important that the field of behavioral genetics identifies not only the gross behavioral phenotypes associated with a given mutation, but also the behavioral endophenotypes that scale with the dosage of the particular mutation being studied. Over the past few years, studies evaluating the effects of the polymorphic CGG trinucleotide repeat on the FMR1 gene underlying Fragile X-Associated Disorders have reported preliminary evidence for a behavioral endophenotype in human Fragile X Premutation carrier populations as well as the CGG knock-in (KI) mouse model. More recently, the behavioral experiments used to test the CGG KI mouse model have been extended to the Fmr1 knock-out (KO) mouse model. When combined, these data provide compelling evidence for a clear neurocognitive endophenotype in the mouse models of Fragile X-Associated Disorders such that behavioral deficits scale predictably with genetic dosage. Similarly, it appears that the CGG KI mouse effectively models the histopathology in Fragile X-Associated Disorders across CGG repeats well into the full mutation range, resulting in a reliable histopathological endophenotype. These endophenotypes may influence future research directions into treatment strategies for not only Fragile X Syndrome, but also the Fragile X Premutation and Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS). PMID:24627796

Long non-coding RNA expression patterns in lung tissues of chronic cigarette smoke induced COPD mouse model.

PubMed

Zhang, Haiyun; Sun, Dejun; Li, Defu; Zheng, Zeguang; Xu, Jingyi; Liang, Xue; Zhang, Chenting; Wang, Sheng; Wang, Jian; Lu, Wenju

2018-05-15

Long non-coding RNAs (lncRNAs) have critical regulatory roles in protein-coding gene expression. Aberrant expression profiles of lncRNAs have been observed in various human diseases. In this study, we investigated transcriptome profiles in lung tissues of chronic cigarette smoke (CS)-induced COPD mouse model. We found that 109 lncRNAs and 260 mRNAs were significantly differential expressed in lungs of chronic CS-induced COPD mouse model compared with control animals. GO and KEGG analyses indicated that differentially expressed lncRNAs associated protein-coding genes were mainly involved in protein processing of endoplasmic reticulum pathway, and taurine and hypotaurine metabolism pathway. The combination of high throughput data analysis and the results of qRT-PCR validation in lungs of chronic CS-induced COPD mouse model, 16HBE cells with CSE treatment and PBMC from patients with COPD revealed that NR_102714 and its associated protein-coding gene UCHL1 might be involved in the development of COPD both in mouse and human. In conclusion, our study demonstrated that aberrant expression profiles of lncRNAs and mRNAs existed in lungs of chronic CS-induced COPD mouse model. From animal models perspective, these results might provide further clues to investigate biological functions of lncRNAs and their potential target protein-coding genes in the pathogenesis of COPD.

Modeling bladder cancer in mice: opportunities and challenges

PubMed Central

Kobayashi, Takashi; Owczarek, Tomasz B.; McKiernan, James M.; Abate-Shen, Cory

2015-01-01

The prognosis and treatment of bladder cancer have hardly improved in the last 20 years. Bladder cancer remains a debilitating and often fatal disease, and among the most costly cancers to treat. The generation of informative mouse models has the potential to improve our understanding of bladder cancer progression, as well as impact its diagnosis and treatment. However, relatively few mouse models of bladder cancer have been described and particularly few that develop invasive cancer phenotypes. This review focuses on opportunities for improving the landscape of mouse models of bladder cancer. PMID:25533675

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

Effect of electroacupuncture on brain-derived neurotrophic factor mRNA expression in mouse hippocampus following cerebral ischemia-reperfusion injury.

PubMed

Zhao, Jianxin; Xu, Huazhou; Tian, Yuanxiang; Hu, Manxiang; Xiao, Hongling

2013-04-01

This work aims to observe the effects of electroacupuncture on brain-derived neurotrophic factor (BDNF) mRNA expression in mouse hippocampus following cerebral ischemia-reperfusion injury. The models of mouse cerebral ischemia-reperfusion injury were established. A total of 96 healthy mice were randomly assigned into 4 groups, namely, the sham surgery, model, model + electroacupuncture, and mode + hydergine groups. Mice in the model + electroacupuncture group were treated through electroacupuncture at the Shenshu (BL 23), Geshu (BL 17), and Baihui (GV 20) acupoints. Mice in the model+hydergine group were intragastrically administered with hydergine (0.77 mg/kg(-1) x day(-1)). The levels of BDNF mRNA expressions in the hippocampus were ana lyzed through a semi-quantitative reverse transcription-polymerase chain reaction assay on days 1 and 7 after the surgeries. BDNF mRNA expressions in the mouse hippocampus of the model group on days 1 and 7 after the surgery were higher than those of the sham surgery group (both P < 0.01). On days 1 and 7 of the electroacupuncture treatment, BDNF mRNA expression in the mouse hippocampus of the model + electroacupuncture group was significantly elevated compared with the model group (both P < 0.01) or the model + hydergine group (both P < 0.01). On days 1 and 7 of the hydergine treatment, BDNF mRNA expression in the mouse hippocampus of the model + hydergine group tended to increase compared with the model group; however, statistical significance was not achieved (both P > 0.05). Electroacupuncture treatment enhances endogenous BDNF expression, which may improve the survival environment for intracerebral neurons and inhibit the apoptosis of hippocampal cells.

Intramyocardial Injection of siRNAs Can Efficiently Establish Myocardial Tissue-Specific Renalase Knockdown Mouse Model.

PubMed

Huang, Kun; Liu, Ju; Zhang, Hui; Wang, Jiliang; Li, Huili

2016-01-01

Ischaemia/reperfusion (I/R) injury will cause additional death of cardiomyocytes in ischaemic heart disease. Recent studies revealed that renalase was involved in the I/R injury. So, the myocardial tissue-specific knockdown mouse models were needed for the investigations of renalase. To establish the mouse models, intramyocardial injection of siRNAs targeting renalase was performed in mice. The wild distribution and high transfection efficiency of the siRNAs were approved. And the renalase expression was efficiently suppressed in myocardial tissue. Compared with the high cost, time consumption, and genetic compensation risk of the Cre/loxP technology, RNA interference (RNAi) technology is much cheaper and less time-consuming. Among the RNAi technologies, injection of siRNAs is safer than virus. And considering the properties of the I/R injury mouse models, the efficiency and durability of injection with siRNAs are acceptable for the studies. Altogether, intramyocardial injection of siRNAs targeting renalase is an economical, safe, and efficient method to establish myocardial tissue-specific renalase knockdown mouse models.

Improvements and Limitations of Humanized Mouse Models for HIV Research: NIH/NIAID "Meet the Experts" 2015 Workshop Summary.

PubMed

Akkina, Ramesh; Allam, Atef; Balazs, Alejandro B; Blankson, Joel N; Burnett, John C; Casares, Sofia; Garcia, J Victor; Hasenkrug, Kim J; Kashanchi, Fatah; Kitchen, Scott G; Klein, Florian; Kumar, Priti; Luster, Andrew D; Poluektova, Larisa Y; Rao, Mangala; Sanders-Beer, Brigitte E; Shultz, Leonard D; Zack, Jerome A

2016-02-01

The number of humanized mouse models for the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and other infectious diseases has expanded rapidly over the past 8 years. Highly immunodeficient mouse strains, such as NOD/SCID/gamma chain(null) (NSG, NOG), support better human hematopoietic cell engraftment. Another improvement is the derivation of highly immunodeficient mice, transgenic with human leukocyte antigens (HLAs) and cytokines that supported development of HLA-restricted human T cells and heightened human myeloid cell engraftment. Humanized mice are also used to study the HIV reservoir using new imaging techniques. Despite these advances, there are still limitations in HIV immune responses and deficits in lymphoid structures in these models in addition to xenogeneic graft-versus-host responses. To understand and disseminate the improvements and limitations of humanized mouse models to the scientific community, the NIH sponsored and convened a meeting on April 15, 2015 to discuss the state of knowledge concerning these questions and best practices for selecting a humanized mouse model for a particular scientific investigation. This report summarizes the findings of the NIH meeting.

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

Production and characterization of monoclonal antibodies against conserved epitopes of P-selectin (CD62P).

PubMed

Massaguer, A; Engel, P; Pérez-del-Pulgar, S; Bosch, J; Pizcueta, P

2000-08-01

P-selectin (CD62P) is an adhesion molecule expressed on the activated endothelium and activated platelets that is involved in the initial attachment of leukocytes to inflamed vascular endothelium. Blocking monoclonal antibodies (mAbs) and P-selectin-deficient mice have shown that P-selectin is a potential target in anti-inflammatory therapy. Most mAbs against P-selectin do not bind to conserved epitopes, including the ligand-binding region, since P-selectin from mammalian species shares high amino acid sequence homology. The aim of this study was to generate a novel panel of anti-P-selectin mAbs against the conserved epitopes present in several animal species. To produce these mAbs, P-selectin-deficient mice were immunized with a pre-B-cell line transfected with human P-selectin cDNA. Twelve mouse mAbs that recognize human P-selectin were obtained. Individual mAbs that bound to human, rat, mouse, rabbit and pig activated platelets were characterized by flow-cytometry, immunohistochemistry, adhesion assays and immunoprecipitation. Four of these mAbs (P-sel.KO.2.3, P-sel.KO.2.4, P-sel.KO.2.7 and P-sel.KO.2.12) cross-reacted with human, rat and mouse P-selectin. Another three mAbs (P-sel.KO.2.2, P-sel.KO.2.11 and P-sel.KO.2.12) blocked the attachment of HL60 cells to P-selectin-transfected COS cells, demonstrating that these mAbs inhibit P-selectin-mediated adhesion. MAb cross-blocking experiments showed that these three mAbs bind to very close and overlapping epitopes. An ELISA assay using mAbs P-sel.KO.2.3 and P-sel.KO.2.12 was designed to measure soluble rat, mouse and human P-selectin. These anti-P-selectin mAbs are unique since they recognize common epitopes conserved during mammalian evolution and they may be useful for studying P-selectin function in inflammatory models in various species.

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.

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.

High-fertility phenotypes: two outbred mouse models exhibit substantially different molecular and physiological strategies warranting improved fertility.

PubMed

Langhammer, Martina; Michaelis, Marten; Hoeflich, Andreas; Sobczak, Alexander; Schoen, Jennifer; Weitzel, Joachim M

2014-01-01

Animal models are valuable tools in fertility research. Worldwide, there are more than 400 transgenic or knockout mouse models available showing a reproductive phenotype; almost all of them exhibit an infertile or at least subfertile phenotype. By contrast, animal models revealing an improved fertility phenotype are barely described. This article summarizes data on two outbred mouse models exhibiting a 'high-fertility' phenotype. These mouse lines were generated via selection over a time period of more than 40 years and 161 generations. During this selection period, the number of offspring per litter and the total birth weight of the entire litter nearly doubled. Concomitantly with the increased fertility phenotype, several endocrine parameters (e.g. serum testosterone concentrations in male animals), physiological parameters (e.g. body weight, accelerated puberty, and life expectancy), and behavioral parameters (e.g. behavior in an open field and endurance fitness on a treadmill) were altered. We demonstrate that the two independently bred high-fertility mouse lines warranted their improved fertility phenotype using different molecular and physiological strategies. The fertility lines display female- as well as male-specific characteristics. These genetically heterogeneous mouse models provide new insights into molecular and cellular mechanisms that enhance fertility. In view of decreasing fertility in men, these models will therefore be a precious information source for human reproductive medicine. Translated abstract A German translation of abstract is freely available at http://www.reproduction-online.org/content/147/4/427/suppl/DC1.

Ultrasonic vocalizations: a tool for behavioural phenotyping of mouse models of neurodevelopmental disorders

PubMed Central

Scattoni, Maria Luisa; Crawley, Jacqueline; Ricceri, Laura

2009-01-01

In neonatal mice ultrasonic vocalizations have been studied both as an early communicative behavior of the pup-mother dyad and as a sign of an aversive affective state. Adult mice of both sexes produce complex ultrasonic vocalization patterns in different experimental/social contexts. All these vocalizations are becoming an increasingly valuable assay for behavioral phenotyping throughout the mouse life-span and alterations of the ultrasound patterns have been reported in several mouse models of neurodevelopmental disorders. Here we also show that the modulation of vocalizations by maternal cues (maternal potentiation paradigm) – originally identified and investigated in rats - can be measured in C57Bl/6 mouse pups with appropriate modifications of the rat protocol and can likely be applied to mouse behavioral phenotyping. In addition we suggest that a detailed qualitative evaluation of neonatal calls together with analysis of adult mouse vocalization patterns in both sexes in social settings, may lead to a greater understanding of the communication value of vocalizations in mice. Importantly, both neonatal and adult USV altered patterns can be determined during the behavioural phenotyping of mouse models of human neurodevelopmental and neuropsychiatric disorders, starting from those in which deficits in communication are a primary symptom. PMID:18771687

Dynamin Regulates Specific Membrane Fusion Events Necessary for Acrosomal Exocytosis in Mouse Spermatozoa

PubMed Central

Reid, Andrew T.; Lord, Tessa; Stanger, Simone J.; Roman, Shaun D.; McCluskey, Adam; Robinson, Phillip J.; Aitken, R. John; Nixon, Brett

2012-01-01

Mammalian spermatozoa must complete an acrosome reaction prior to fertilizing an oocyte. The acrosome reaction is a unique exocytotic event involving a series of prolonged membrane fusions that ultimately result in the production of membrane vesicles and release of the acrosomal contents. This event requires the concerted action of a large number of fusion-competent signaling and scaffolding proteins. Here we show that two different members of the dynamin GTPase family localize to the developing acrosome of maturing mouse germ cells. Both dynamin 1 and 2 also remain within the periacrosomal region of mature mouse spermatozoa and are thus well positioned to regulate the acrosome reaction. Two pharmacological inhibitors of dynamin, dynasore and Dyngo-4a, blocked the in vitro induction of acrosomal exocytosis by progesterone, but not by the calcium ionophore A23187, and elicited a concomitant reduction of in vitro fertilization. In vivo treatment with these inhibitors also resulted in spermatozoa displaying reduced acrosome reaction potential. Dynamin 1 and 2 phosphorylation increased on progesterone treatment, and this was also selectively blocked by dynasore. On the basis of our collective data, we propose that dynamin could regulate specific membrane fusion events necessary for acrosomal exocytosis in mouse spermatozoa. PMID:22977254

A Comparison of Some Organizational Characteristics of the Mouse Central Retina and the Human Macula

PubMed Central

Hoo, Juyea; Yee, Claudine; Williams, David S.

2015-01-01

Mouse models have greatly assisted our understanding of retinal degenerations. However, the mouse retina does not have a macula, leading to the question of whether the mouse is a relevant model for macular degeneration. In the present study, a quantitative comparison between the organization of the central mouse retina and the human macula was made, focusing on some structural characteristics that have been suggested to be important in predisposing the macula to stresses leading to degeneration: photoreceptor density, phagocytic load on the RPE, and the relative thinness of Bruch’s membrane. Light and electron microscopy measurements from retinas of two strains of mice, together with published data on human retinas, were used for calculations and subsequent comparisons. As in the human retina, the central region of the mouse retina possesses a higher photoreceptor cell density and a thinner Bruch’s membrane than in the periphery; however, the magnitudes of these periphery to center gradients are larger in the human. Of potentially greater relevance is the actual photoreceptor cell density, which is much greater in the mouse central retina than in the human macula, underlying a higher phagocytic load for the mouse RPE. Moreover, at eccentricities that correspond to the peripheral half of the human macula, the rod to cone ratio is similar between mouse and human. Hence, with respect to photoreceptor density and phagocytic load of the RPE, the central mouse retina models at least the more peripheral part of the macula, where macular degeneration is often first evident. PMID:25923208

Protective and therapeutic role of 2-carba-cyclic phosphatidic acid in demyelinating disease.

PubMed

Yamamoto, Shinji; Yamashina, Kota; Ishikawa, Masaki; Gotoh, Mari; Yagishita, Sosuke; Iwasa, Kensuke; Maruyama, Kei; Murakami-Murofushi, Kimiko; Yoshikawa, Keisuke

2017-07-21

Multiple sclerosis is a neuroinflammatory demyelinating and neurodegenerative disease of the central nervous system characterized by recurrent and progressive demyelination/remyelination cycles, neuroinflammation, oligodendrocyte loss, demyelination, and axonal degeneration. Cyclic phosphatidic acid (cPA) is a natural phospholipid mediator with a unique cyclic phosphate ring structure at the sn-2 and sn-3 positions of the glycerol backbone. We reported earlier that cPA elicits a neurotrophin-like action and protects hippocampal neurons from ischemia-induced delayed neuronal death. We designed, chemically synthesized, and metabolically stabilized derivatives of cPA: 2-carba-cPA (2ccPA), a synthesized compound in which one of the phosphate oxygen molecules is replaced with a methylene group at the sn-2 position. In the present study, we investigated whether 2ccPA exerts protective effects in oligodendrocytes and suppresses pathology in the two most common mouse models of multiple sclerosis. To evaluate whether 2ccPA has potential beneficial effects on the pathology of multiple sclerosis, we investigated the effects of 2ccPA on oligodendrocyte cell death in vitro and administrated 2ccPA to mouse models of experimental autoimmune encephalomyelitis (EAE) and cuprizone-induced demyelination. We demonstrated that 2ccPA suppressed the CoCl 2 -induced increase in the Bax/Bcl-2 protein expression ratio and phosphorylation levels of p38MAPK and JNK protein. 2ccPA treatment reduced cuprizone-induced demyelination, microglial activation, NLRP3 inflammasome, and motor dysfunction. Furthermore, 2ccPA treatment reduced autoreactive T cells and macrophages, spinal cord injury, and pathological scores in EAE, the autoimmune multiple sclerosis mouse model. We demonstrated that 2ccPA protected oligodendrocytes via suppression of the mitochondrial apoptosis pathway. Also, we found beneficial effects of 2ccPA in the multiperiod of cuprizone-induced demyelination and the pathology of EAE. These data indicate that 2ccPA may be a promising compound for the development of new drugs to treat demyelinating disease and ameliorate the symptoms of multiple sclerosis.

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

Ding, Ying; Adachi, Hiroaki, E-mail: hadachi-ns@umin.org; Department of Neurology, University of Occupational and Environmental Health School of Medicine, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555

Spinal and bulbar muscular atrophy (SBMA) is an inherited motor neuron disease caused by the expansion of a polyglutamine (polyQ)-encoding tract within the androgen receptor (AR) gene. The pathologic features of SBMA are motor neuron loss in the spinal cord and brainstem and diffuse nuclear accumulation and nuclear inclusions of mutant AR in residual motor neurons and certain visceral organs. Hepatocyte growth factor (HGF) is a polypeptide growth factor which has neuroprotective properties. To investigate whether HGF overexpression can affect disease progression in a mouse model of SBMA, we crossed SBMA transgenic model mice expressing an AR gene with anmore » expanded CAG repeat with mice overexpressing HGF. Here, we report that high expression of HGF induces Akt phosphorylation and modestly ameliorated motor symptoms in an SBMA transgenic mouse model treated with or without castration. These findings suggest that HGF overexpression can provide a potential therapeutic avenue as a combination therapy with disease-modifying therapies in SBMA. - Highlights: • HGF overexpression ameliorates the motor phenotypes of the SBMA mouse model. • HGF overexpression induces Akt phosphorylation in the SBMA mouse model. • This is the first report of combination therapy in a mouse model of polyQ diseases.« less

Defining the optimal animal model for translational research using gene set enrichment analysis.

PubMed

Weidner, Christopher; Steinfath, Matthias; Opitz, Elisa; Oelgeschläger, Michael; Schönfelder, Gilbert

2016-08-01

The mouse is the main model organism used to study the functions of human genes because most biological processes in the mouse are highly conserved in humans. Recent reports that compared identical transcriptomic datasets of human inflammatory diseases with datasets from mouse models using traditional gene-to-gene comparison techniques resulted in contradictory conclusions regarding the relevance of animal models for translational research. To reduce susceptibility to biased interpretation, all genes of interest for the biological question under investigation should be considered. Thus, standardized approaches for systematic data analysis are needed. We analyzed the same datasets using gene set enrichment analysis focusing on pathways assigned to inflammatory processes in either humans or mice. The analyses revealed a moderate overlap between all human and mouse datasets, with average positive and negative predictive values of 48 and 57% significant correlations. Subgroups of the septic mouse models (i.e., Staphylococcus aureus injection) correlated very well with most human studies. These findings support the applicability of targeted strategies to identify the optimal animal model and protocol to improve the success of translational research. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

Regulation of VEGF signaling by membrane traffic.

PubMed

Horowitz, Arie; Seerapu, Himabindu Reddy

2012-09-01

Recent findings have drawn attention to the role of membrane traffic in the signaling of vascular endothelial growth factor (VEGF). The significance of this development stems from the pivotal function of VEGF in vasculogenesis and angiogenesis. The outline of the regulation of VEGF receptor (VEGFR) signaling by membrane traffic is similar to that of the epidermal growth factor receptor (EGFR), a prototype of the intertwining between membrane traffic and signaling. There are, however, unique features in VEGFR signaling that are conferred in part by the involvement of the co-receptor neuropilin (Nrp). Nrp1 and VEGFR2 are integrated into membrane traffic through the adaptor protein synectin, which recruits myosin VI, a molecular motor that drives inward trafficking [17,21,64]. The recent detection of only mild vascular defects in a knockin mouse model that expresses Nrp1 lacking a cytoplasmic domain [104], questions the co-receptor's role in VEGF signaling and membrane traffic. The regulation of endocytosis by ephrin-B2 is another feature unique to VEGR2/3 [18,19], but it awaits a mechanistic explanation. Current models do not fully explain how membrane traffic bridges between VEGFR and the downstream effectors that produce its functional outcome, such as cell migration. VEGF-A appears to accomplish this task in part by recruiting endocytic vesicles carrying RhoA to internalized active VEGFR2 [58]. Copyright © 2012 Elsevier Inc. All rights reserved.

Transgenic and gene knockout mice in gastric cancer research

PubMed Central

Jiang, Yannan; Yu, Yingyan

2017-01-01

Mouse models are useful tool for carcinogenic study. They will greatly enrich the understanding of pathogenesis and molecular mechanisms for gastric cancer. However, only few of mice could develop gastric cancer spontaneously. With the development and improvement of gene transfer technology, investigators created a variety of transgenic and knockout/knockin mouse models of gastric cancer, such as INS-GAS mice and gastrin knockout mice. Combined with helicobacter infection and carcinogens treatment, these transgenic/knockout/knockin mice developed precancerous or cancerous lesions, which are proper for gene function study or experimental therapy. Here we review the progression of genetically engineered mouse models on gastric cancer research, and emphasize the effects of chemical carcinogens or infectious factors on carcinogenesis of genetically modified mouse. We also emphasize the histological examination on mouse stomach. We expect to provide researchers with some inspirations on this field. PMID:27713138

A Mouse Model to Investigate Postmenopausal Biology as an Etiology of Ovarian Cancer Risk

DTIC Science & Technology

2006-11-01

Wv mice and genetic alterations such as p53, pten, or p27kip1, which are found in human ovarian cancer. 2. Body: Research Progress In the first year...press (Yang et al., Am. J. Pathology 2007). To collaborate with the mouse model study, we have also examined human ovaries obtained from prophylactic...results in the coming years. Xu, Xiangxi, Ph.D. 8 3. Key Research Accomplishments (1) Further verify the relevance of the Wv mouse model to human

The Oncogenic Role of RhoGAPs in Basal-Like Breast Cancer

DTIC Science & Technology

2015-02-01

cell lines, and mouse models . c) In vivo tumorigenesis and metastasis assays. Milestones: Identify whether ArhGAP11A and RacGAP1 can promote tumor growth...also upregulated in basal (C3(I)-Tag) but not luminal (MMTV-Neu) genetically- engineered mouse models (Fig. 1B). At the protein level, RacGAP1 was...hypothesis that these RhoGAPs are indeed playing an oncogenic role in these cells. Human Tumors Mouse Model Tumors Normal Luminal A Basal-like Normal

Bloomsbury report on mouse embryo phenotyping: recommendations from the IMPC workshop on embryonic lethal screening.

PubMed

Adams, David; Baldock, Richard; Bhattacharya, Shoumo; Copp, Andrew J; Dickinson, Mary; Greene, Nicholas D E; Henkelman, Mark; Justice, Monica; Mohun, Timothy; Murray, Stephen A; Pauws, Erwin; Raess, Michael; Rossant, Janet; Weaver, Tom; West, David

2013-05-01

Identifying genes that are important for embryo development is a crucial first step towards understanding their many functions in driving the ordered growth, differentiation and organogenesis of embryos. It can also shed light on the origins of developmental disease and congenital abnormalities. Current international efforts to examine gene function in the mouse provide a unique opportunity to pinpoint genes that are involved in embryogenesis, owing to the emergence of embryonic lethal knockout mutants. Through internationally coordinated efforts, the International Knockout Mouse Consortium (IKMC) has generated a public resource of mouse knockout strains and, in April 2012, the International Mouse Phenotyping Consortium (IMPC), supported by the EU InfraCoMP programme, convened a workshop to discuss developing a phenotyping pipeline for the investigation of embryonic lethal knockout lines. This workshop brought together over 100 scientists, from 13 countries, who are working in the academic and commercial research sectors, including experts and opinion leaders in the fields of embryology, animal imaging, data capture, quality control and annotation, high-throughput mouse production, phenotyping, and reporter gene analysis. This article summarises the outcome of the workshop, including (1) the vital scientific importance of phenotyping embryonic lethal mouse strains for basic and translational research; (2) a common framework to harmonise international efforts within this context; (3) the types of phenotyping that are likely to be most appropriate for systematic use, with a focus on 3D embryo imaging; (4) the importance of centralising data in a standardised form to facilitate data mining; and (5) the development of online tools to allow open access to and dissemination of the phenotyping data.

Locations of the ets subfamily members net, elk1, and sap1 (ELK3, ELK1, and ELK4) on three homologous regions of the mouse and human genomes

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

Giovane, A.; Sobieszczuk, P.; Mignon, C.

1995-10-10

Net, Elk1, and Sap1 are related members of the Ets oncoprotein family. We show by in situ hybridization on banded chromosomes with specific cDNA probes that their map positions on mouse and human chromosomes (respectively) are net, 10C-D1 and 12q22-q23 (now called ELK3), sap1, 1E3-G and 1q32 (ELK4), and elk1, XA1-A3 and Xp11.2-p11.1 (ELK1), as well as a second locus 14q32 (ELK2) unique to the human genome. The results for the mouse net, sap1, and elk1 and human ELK3 genes are new. The human elk1 mapping confirms a previous study. The human ELK4 localization agrees with data published during themore » preparation of the manuscript. Human ELK3 colocalizes with sap2, and we confirm that they are identical. These results firmly establish for the first time that Net, Elk1, and Sap1 are distinct gene products with different chromosomal localizations in both the mouse and the human genomes. Net, Elk1, and Sap1 are conserved and map to homologous regions of the mouse and human chromosomes. 19 refs., 1 fig., 1 tab.« less

A Simplified, Langendorff-Free Method for Concomitant Isolation of Viable Cardiac Myocytes and Nonmyocytes From the Adult Mouse Heart

PubMed Central

Ackers-Johnson, Matthew; Li, Peter Yiqing; Holmes, Andrew P.; O’Brien, Sian-Marie; Pavlovic, Davor; Foo, Roger S.

2018-01-01

Rationale Cardiovascular disease represents a global pandemic. The advent of and recent advances in mouse genomics, epigenomics, and transgenics offer ever-greater potential for powerful avenues of research. However, progress is often constrained by unique complexities associated with the isolation of viable myocytes from the adult mouse heart. Current protocols rely on retrograde aortic perfusion using specialized Langendorff apparatus, which poses considerable logistical and technical barriers to researchers and demands extensive training investment. Objective To identify and optimize a convenient, alternative approach, allowing the robust isolation and culture of adult mouse cardiac myocytes using only common surgical and laboratory equipment. Methods and Results Cardiac myocytes were isolated with yields comparable to those in published Langendorff-based methods, using direct needle perfusion of the LV ex vivo and without requirement for heparin injection. Isolated myocytes can be cultured antibiotic free, with retained organized contractile and mitochondrial morphology, transcriptional signatures, calcium handling, responses to hypoxia, neurohormonal stimulation, and electric pacing, and are amenable to patch clamp and adenoviral gene transfer techniques. Furthermore, the methodology permits concurrent isolation, separation, and coculture of myocyte and nonmyocyte cardiac populations. Conclusions We present a novel, simplified method, demonstrating concomitant isolation of viable cardiac myocytes and nonmyocytes from the same adult mouse heart. We anticipate that this new approach will expand and accelerate innovative research in the field of cardiac biology. PMID:27502479

A Physiologically Based Kinetic Model of Rat and Mouse Gestation: Disposition of a Weak Acid

EPA Science Inventory

A physiologically based toxicokinetic model of gestation in the rat mouse has been developed. The model is superimposed on the normal growth curve for nonpregnant females. It describes the entire gestation period including organogenesis. The model consists of uterus, mammary tiss...

Priceless GEMMs: genetically engineered mouse models for colorectal cancer drug development.

PubMed

Roper, Jatin; Hung, Kenneth E

2012-08-01

To establish effective drug development for colorectal cancer (CRC), preclinical models that are robust surrogates for human disease are crucial. Mouse models are an attractive platform because of their relatively low cost, short life span, and ease of use. There are two main categories of mouse CRC models: xenografts derived from implantation of CRC cells or tumors in immunodeficient mice; and genetically engineered mouse models (GEMMs) derived from modification of human cancer predisposition genes, resulting in spontaneous tumor formation. Here, we review xenografts and GEMMs and focus on their potential application in translational research. Furthermore, we describe newer GEMMs for sporadic CRC that are particularly suitable for drug testing. Finally, we discuss recent advances in small-animal imaging, such as optical colonoscopy, which allow in vivo assessment of tumors. With the increasing sophistication of GEMMs, our preclinical armamentarium provides new hope for the ongoing war against CRC. Copyright © 2012. Published by Elsevier Ltd.

A Genetically Engineered Mouse Model of Sporadic Colorectal Cancer.

PubMed

Betzler, Alexander M; Kochall, Susan; Blickensdörfer, Linda; Garcia, Sebastian A; Thepkaysone, May-Linn; Nanduri, Lahiri K; Muders, Michael H; Weitz, Jürgen; Reissfelder, Christoph; Schölch, Sebastian

2017-07-06

Despite the advantages of easy applicability and cost-effectiveness, colorectal cancer mouse models based on tumor cell injection have severe limitations and do not accurately simulate tumor biology and tumor cell dissemination. Genetically engineered mouse models have been introduced to overcome these limitations; however, such models are technically demanding, especially in large organs such as the colon in which only a single tumor is desired. As a result, an immunocompetent, genetically engineered mouse model of colorectal cancer was developed which develops highly uniform tumors and can be used for tumor biology studies as well as therapeutic trials. Tumor development is initiated by surgical, segmental infection of the distal colon with adeno-cre virus in compound conditionally mutant mice. The tumors can be easily detected and monitored via colonoscopy. We here describe the surgical technique of segmental adeno-cre infection of the colon, the surveillance of the tumor via high-resolution colonoscopy and present the resulting colorectal tumors.

RP5063, an atypical antipsychotic drug with a unique pharmacologic profile, improves declarative memory and psychosis in mouse models of schizophrenia.

PubMed

Rajagopal, Lakshmi; Kwon, Sunoh; Huang, Mei; Michael, Eric; Bhat, Laxminarayan; Cantillon, Marc; Meltzer, Herbert Y

2017-08-14

Various types of atypical antipsychotic drugs (AAPDs) modestly improve the cognitive impairment associated with schizophrenia (CIAS). RP5063 is an AAPD with a diverse and unique pharmacology, including partial agonism at dopamine (DA) D 2 , D 3 , D 4 , serotonin (5-HT) 1A , and 5-HT 2A receptors (Rs), full agonism at α 4 β 2 nicotinic acetylcholine (ACh)R (nAChR), and antagonism at 5-HT 2B , 5-HT 6 , and 5-HT 7 Rs. Most atypical APDs are 5-HT 2A inverse agonists. The efficacy of RP5063 in mouse models of psychosis and episodic memory were studied. RP5063 blocked acute phencyclidine (PCP)-as well as amphetamine-induced hyperactivity, indicating antipsychotic activity. Acute administration of RP5063 significantly reversed subchronic (sc)PCP-induced impairment in novel object recognition (NOR), a measure of episodic memory, but not reversal learning, a measure of executive function. Co-administration of a sub-effective dose (SED) of RP5063 with SEDs of a 5-HT 7 R antagonist, a 5-HT 1B R antagonist, a 5-HT 2A R inverse agonist, or an α 4 β 2 nAChR agonist, restored the ability of RP5063 to ameliorate the NOR deficit in scPCP mice. Pre-treatment with a 5-HT 1A R, a D 4 R, antagonist, but not an α 4 β 2 nAChR antagonist, blocked the ameliorating effect of RP5063. Further, co-administration of scRP5063 prior to each dose of PCP prevented the effect of PCP to produce a deficit in NOR for one week. RP5063, given to scPCP-treated mice for one week restored NOR for one week only. Acute administration of RP5063 significantly increased cortical DA efflux, which may be critical to some of its cognitive enhancing properties. These results indicate that RP5063, by itself, or as an adjunctive treatment has a multifaceted basis for improving some cognitive deficits associated with schizophrenia. Copyright © 2017. Published by Elsevier B.V.

A robust automated system elucidates mouse home cage behavioral structure

PubMed Central

Goulding, Evan H.; Schenk, A. Katrin; Juneja, Punita; MacKay, Adrienne W.; Wade, Jennifer M.; Tecott, Laurence H.

2008-01-01

Patterns of behavior exhibited by mice in their home cages reflect the function and interaction of numerous behavioral and physiological systems. Detailed assessment of these patterns thus has the potential to provide a powerful tool for understanding basic aspects of behavioral regulation and their perturbation by disease processes. However, the capacity to identify and examine these patterns in terms of their discrete levels of organization across diverse behaviors has been difficult to achieve and automate. Here, we describe an automated approach for the quantitative characterization of fundamental behavioral elements and their patterns in the freely behaving mouse. We demonstrate the utility of this approach by identifying unique features of home cage behavioral structure and changes in distinct levels of behavioral organization in mice with single gene mutations altering energy balance. The robust, automated, reproducible quantification of mouse home cage behavioral structure detailed here should have wide applicability for the study of mammalian physiology, behavior, and disease. PMID:19106295

A novel method of mouse ex utero transplantation of hepatic progenitor cells into the fetal liver

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

Shikanai, Mima; Asahina, Kinji; Iseki, Sachiko

2009-04-03

Avoiding the limitations of the adult liver niche, transplantation of hepatic stem/progenitor cells into fetal liver is desirable to analyze immature cells in a hepatic developmental environment. Here, we established a new monitor tool for cell fate of hepatic progenitor cells transplanted into the mouse fetal liver by using ex utero surgery. When embryonic day (ED) 14.5 hepatoblasts were injected into the ED14.5 fetal liver, the transplanted cells expressed albumin abundantly or {alpha}-fetoprotein weakly, and contained glycogen in the neonatal liver, indicating that transplanted hepatoblasts can proliferate and differentiate in concord with surrounding recipient parenchymal cells. The transplanted cells becamemore » mature in the liver of 6-week-old mice. Furthermore, this method was applicable to transplantation of hepatoblast-like cells derived from mouse embryonic stem cells. These data indicate that this unique technique will provide a new in vivo experimental system for studying cell fate of hepatic stem/progenitor cells and liver organogenesis.« less

Intra-spindle Microtubule Assembly Regulates Clustering of Microtubule-Organizing Centers during Early Mouse Development.

PubMed

Watanabe, Sadanori; Shioi, Go; Furuta, Yasuhide; Goshima, Gohta

2016-04-05

Errors during cell division in oocytes and early embryos are linked to birth defects in mammals. Bipolar spindle assembly in early mouse embryos is unique in that three or more acentriolar microtubule-organizing centers (MTOCs) are initially formed and are then clustered into two spindle poles. Using a knockout mouse and live imaging of spindles in embryos, we demonstrate that MTOC clustering during the blastocyst stage requires augmin, a critical complex for MT-dependent MT nucleation within the spindle. Functional analyses in cultured cells with artificially increased numbers of centrosomes indicate that the lack of intra-spindle MT nucleation, but not loss of augmin per se or overall reduction of spindle MTs, is the cause of clustering failure. These data suggest that onset of mitosis with three or more MTOCs is turned into a typical bipolar division through augmin-dependent intra-spindle MT assembly. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Serum amyloid A is a retinol binding protein that transports retinol during bacterial infection

PubMed Central

Derebe, Mehabaw G; Zlatkov, Clare M; Gattu, Sureka; Ruhn, Kelly A; Vaishnava, Shipra; Diehl, Gretchen E; MacMillan, John B; Williams, Noelle S; Hooper, Lora V

2014-01-01

Retinol plays a vital role in the immune response to infection, yet proteins that mediate retinol transport during infection have not been identified. Serum amyloid A (SAA) proteins are strongly induced in the liver by systemic infection and in the intestine by bacterial colonization, but their exact functions remain unclear. Here we show that mouse and human SAAs are retinol binding proteins. Mouse and human SAAs bound retinol with nanomolar affinity, were associated with retinol in vivo, and limited the bacterial burden in tissues after acute infection. We determined the crystal structure of mouse SAA3 at a resolution of 2 Å, finding that it forms a tetramer with a hydrophobic binding pocket that can accommodate retinol. Our results thus identify SAAs as a family of microbe-inducible retinol binding proteins, reveal a unique protein architecture involved in retinol binding, and suggest how retinol is circulated during infection. DOI: http://dx.doi.org/10.7554/eLife.03206.001 PMID:25073702

Precise assignment of the heavy-strand promoter of mouse mitochondrial DNA: cognate start sites are not required for transcriptional initiation.

PubMed Central

Chang, D D; Clayton, D A

1986-01-01

Transcription of the heavy strand of mouse mitochondrial DNA starts from two closely spaced, distinct sites located in the displacement loop region of the genome. We report here an analysis of regulatory sequences required for faithful transcription from these two sites. Data obtained from in vitro assays demonstrated that a 51-base-pair region, encompassing nucleotides -40 to +11 of the downstream start site, contains sufficient information for accurate transcription from both start sites. Deletion of the 3' flanking sequences, including one or both start sites to -17, resulted in the initiation of transcription by the mitochondrial RNA polymerase from alternative sites within vector DNA sequences. This feature places the mouse heavy-strand promoter uniquely among other known mitochondrial promoters, all of which absolutely require cognate start sites for transcription. Comparison of the heavy-strand promoter with those of other vertebrate mitochondrial DNAs revealed a remarkably high rate of sequence divergence among species. Images PMID:3785226

Analysis of mammalian gene function through broad-based phenotypic screens across a consortium of mouse clinics.

PubMed

de Angelis, Martin Hrabě; Nicholson, George; Selloum, Mohammed; White, Jacqui; Morgan, Hugh; Ramirez-Solis, Ramiro; Sorg, Tania; Wells, Sara; Fuchs, Helmut; Fray, Martin; Adams, David J; Adams, Niels C; Adler, Thure; Aguilar-Pimentel, Antonio; Ali-Hadji, Dalila; Amann, Gregory; André, Philippe; Atkins, Sarah; Auburtin, Aurelie; Ayadi, Abdel; Becker, Julien; Becker, Lore; Bedu, Elodie; Bekeredjian, Raffi; Birling, Marie-Christine; Blake, Andrew; Bottomley, Joanna; Bowl, Mike; Brault, Véronique; Busch, Dirk H; Bussell, James N; Calzada-Wack, Julia; Cater, Heather; Champy, Marie-France; Charles, Philippe; Chevalier, Claire; Chiani, Francesco; Codner, Gemma F; Combe, Roy; Cox, Roger; Dalloneau, Emilie; Dierich, André; Di Fenza, Armida; Doe, Brendan; Duchon, Arnaud; Eickelberg, Oliver; Esapa, Chris T; El Fertak, Lahcen; Feigel, Tanja; Emelyanova, Irina; Estabel, Jeanne; Favor, Jack; Flenniken, Ann; Gambadoro, Alessia; Garrett, Lilian; Gates, Hilary; Gerdin, Anna-Karin; Gkoutos, George; Greenaway, Simon; Glasl, Lisa; Goetz, Patrice; Da Cruz, Isabelle Goncalves; Götz, Alexander; Graw, Jochen; Guimond, Alain; Hans, Wolfgang; Hicks, Geoff; Hölter, Sabine M; Höfler, Heinz; Hancock, John M; Hoehndorf, Robert; Hough, Tertius; Houghton, Richard; Hurt, Anja; Ivandic, Boris; Jacobs, Hughes; Jacquot, Sylvie; Jones, Nora; Karp, Natasha A; Katus, Hugo A; Kitchen, Sharon; Klein-Rodewald, Tanja; Klingenspor, Martin; Klopstock, Thomas; Lalanne, Valerie; Leblanc, Sophie; Lengger, Christoph; le Marchand, Elise; Ludwig, Tonia; Lux, Aline; McKerlie, Colin; Maier, Holger; Mandel, Jean-Louis; Marschall, Susan; Mark, Manuel; Melvin, David G; Meziane, Hamid; Micklich, Kateryna; Mittelhauser, Christophe; Monassier, Laurent; Moulaert, David; Muller, Stéphanie; Naton, Beatrix; Neff, Frauke; Nolan, Patrick M; Nutter, Lauryl Mj; Ollert, Markus; Pavlovic, Guillaume; Pellegata, Natalia S; Peter, Emilie; Petit-Demoulière, Benoit; Pickard, Amanda; Podrini, Christine; Potter, Paul; Pouilly, Laurent; Puk, Oliver; Richardson, David; Rousseau, Stephane; Quintanilla-Fend, Leticia; Quwailid, Mohamed M; Racz, Ildiko; Rathkolb, Birgit; Riet, Fabrice; Rossant, Janet; Roux, Michel; Rozman, Jan; Ryder, Ed; Salisbury, Jennifer; Santos, Luis; Schäble, Karl-Heinz; Schiller, Evelyn; Schrewe, Anja; Schulz, Holger; Steinkamp, Ralf; Simon, Michelle; Stewart, Michelle; Stöger, Claudia; Stöger, Tobias; Sun, Minxuan; Sunter, David; Teboul, Lydia; Tilly, Isabelle; Tocchini-Valentini, Glauco P; Tost, Monica; Treise, Irina; Vasseur, Laurent; Velot, Emilie; Vogt-Weisenhorn, Daniela; Wagner, Christelle; Walling, Alison; Weber, Bruno; Wendling, Olivia; Westerberg, Henrik; Willershäuser, Monja; Wolf, Eckhard; Wolter, Anne; Wood, Joe; Wurst, Wolfgang; Yildirim, Ali Önder; Zeh, Ramona; Zimmer, Andreas; Zimprich, Annemarie; Holmes, Chris; Steel, Karen P; Herault, Yann; Gailus-Durner, Valérie; Mallon, Ann-Marie; Brown, Steve Dm

2015-09-01

The function of the majority of genes in the mouse and human genomes remains unknown. The mouse embryonic stem cell knockout resource provides a basis for the characterization of relationships between genes and phenotypes. The EUMODIC consortium developed and validated robust methodologies for the broad-based phenotyping of knockouts through a pipeline comprising 20 disease-oriented platforms. We developed new statistical methods for pipeline design and data analysis aimed at detecting reproducible phenotypes with high power. We acquired phenotype data from 449 mutant alleles, representing 320 unique genes, of which half had no previous functional annotation. We captured data from over 27,000 mice, finding that 83% of the mutant lines are phenodeviant, with 65% demonstrating pleiotropy. Surprisingly, we found significant differences in phenotype annotation according to zygosity. New phenotypes were uncovered for many genes with previously unknown function, providing a powerful basis for hypothesis generation and further investigation in diverse systems.

Absence of Prenatal Forebrain Defects in the Dp(16)1Yey/+ Mouse Model of Down Syndrome

PubMed Central

Goodliffe, Joseph W.; Olmos-Serrano, Jose Luis; Aziz, Nadine M.; Pennings, Jeroen L.A.; Guedj, Faycal; Bianchi, Diana W.

2016-01-01

Studies in humans with Down syndrome (DS) show that alterations in fetal brain development are followed by postnatal deficits in neuronal numbers, synaptic plasticity, and cognitive and motor function. This same progression is replicated in several mouse models of DS. Dp(16)1Yey/+ (hereafter called Dp16) is a recently developed mouse model of DS in which the entire region of mouse chromosome 16 that is homologous to human chromosome 21 has been triplicated. As such, Dp16 mice may more closely reproduce neurodevelopmental changes occurring in humans with DS. Here, we present the first comprehensive cellular and behavioral study of the Dp16 forebrain from embryonic to adult stages. Unexpectedly, our results demonstrate that Dp16 mice do not have prenatal brain defects previously reported in human fetal neocortex and in the developing forebrains of other mouse models, including microcephaly, reduced neurogenesis, and abnormal cell proliferation. Nevertheless, we found impairments in postnatal developmental milestones, fewer inhibitory forebrain neurons, and deficits in motor and cognitive performance in Dp16 mice. Therefore, although this new model does not express prenatal morphological phenotypes associated with DS, abnormalities in the postnatal period appear sufficient to produce significant cognitive deficits in Dp16. SIGNIFICANCE STATEMENT Down syndrome (DS) leads to intellectual disability. Several mouse models have increased our understanding of the neuropathology of DS and are currently being used to test therapeutic strategies. A new mouse model that contains an expanded number of DS-related genes, known as Dp(16)1Yey/+ (Dp16), has been generated recently. We sought to determine whether the extended triplication creates a better phenocopy of DS-related brain pathologies. We measured embryonic development, forebrain maturation, and perinatal/adult behavior and revealed an absence of prenatal phenotypes in Dp16 fetal brain, but specific cellular and behavioral deficits after the first 2 postnatal weeks. These results uncover important differences in prenatal phenotype between Dp16 animals and humans with DS and other DS mouse models. PMID:26961948

Use of a highly sensitive strand-specific quantitative PCR to identify abortive replication in the mouse model of respiratory syncytial virus disease

PubMed Central

2010-01-01

Background The BALB/c mouse is commonly used to study RSV infection and disease. However, despite the many advantages of this well-characterised model, the inoculum is large, viral replication is restricted and only a very small amount of virus can be recovered from infected animals. A key question in this model is the fate of the administered virus. Is replication really being measured or is the model measuring the survival of the virus over time? To answer these questions we developed a highly sensitive strand-specific quantitative PCR (QPCR) able to accurately quantify the amount of RSV replication in the BALB/c mouse lung, allowing characterisation of RSV negative and positive strand RNA dynamics. Results In the mouse lung, no increase in RSV genome was seen above the background of the original inoculum whilst only a limited transient increase (< 1 log) in positive strand, replicative intermediate (RI) RNA occurred. This RNA did however persist at detectable levels for 59 days post infection. As expected, ribavirin therapy reduced levels of infectious virus and RI RNA in the mouse lung. However, whilst Palivizumab therapy was also able to reduce levels of infectious virus, it failed to prevent production of intracellular RI RNA. A comparison of RSV RNA kinetics in human (A549) and mouse (KLN205) cell lines demonstrated that RSV replication was also severely delayed and impaired in vitro in the mouse cells. Conclusions This is the first time that such a sensitive strand-specific QPCR technique has been to the RSV mouse system. We have accurately quantified the restricted and abortive nature of RSV replication in the mouse. Further in vitro studies in human and mouse cells suggest this restricted replication is due at least in part to species-specific host cell-viral interactions. PMID:20860795

Establishment of mouse neuron and microglial cell co-cultured models and its action mechanism.

PubMed

Zhang, Bo; Yang, Yunfeng; Tang, Jun; Tao, Yihao; Jiang, Bing; Chen, Zhi; Feng, Hua; Yang, Liming; Zhu, Gang

2017-06-27

The objective of this study is to establish a co-culture model of mouse neurons and microglial cells, and to analyze the mechanism of action of oxygen glucose deprivation (OGD) and transient oxygen glucose deprivation (tOGD) preconditioning cell models. Mouse primary neurons and BV2 microglial cells were successfully cultured, and the OGD and tOGD models were also established. In the co-culture of mouse primary neurons and microglial cells, the cell number of tOGD mouse neurons and microglial cells was larger than the OGD cell number, observed by a microscope. CCK-8 assay result showed that at 1h after treatment, the OD value in the control group is lower compared to all the other three groups (P < 0.05). The treatment group exhibited the highest OD value among the four groups. The results observed at 5h were consistent with the results at 1 h. Flow cytometry results showed that at 1h after treatment the apoptosis percentages is higher in the control group compared to other three groups (P < 0.05). Mouse brain tissues were collected and primary neurons cells were cultured. In the meantime mouse BV2 microglia cells were cultured. Two types of cells were co-cultured, and OGD and tOGD cell models were established. There were four groups in the experiment: control group (OGD), treatment group (tOGD+OGD), placebo group (tOGD+OGD+saline) and minocycline intervention group (tOGD+OGD+minocycline). CCK-8 kit was used to detect cell viability and flow cytometry was used to detect apoptosis. In this study, mouse primary neurons and microglial cells were co-cultured. The OGD and tOGD models were established successfully. tOGD was able to effectively protect neurons and microglial cells from damage, and inhibit the apoptosis caused by oxygen glucose deprivation.

Cloning of the anhidrotic ectodermal dysplasia gene: Identification of cDNAs associated with CpG islands mapped near translocation breakpoint in two female patients

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

Srivastava, A.K.; Schlessinger, D.; Kere, J.

1994-09-01

The gene for the X chromosomal developmental disorder anhidrotic ectodermal dysplasia (EDA) has been mapped to Xq12-q13 by linkage analysis and is expressed in a few females with chromosomal translocations involving band Xq12-q13. A yeast artificial chromosome (YAC) contig (2.0 Mb) spanning two translocation breakpoints has been assembled by sequence-tagged site (STS)-based chromosomal walking. The two translocation breakpoints (X:autosome translocations from the affected female patients) have been mapped less than 60 kb apart within a YAC contig. Unique probes and intragenic STSs (mapped between the two translocations) have been developed and a somatic cell hybrid carrying the translocated X chromosomemore » from the AK patient has been analyzed by isolating unique probes that span the breakpoint. Several STSs made from intragenic sequences have been found to be conserved in mouse, hamster and monkey, but we have detected no mRNAs in a number of tissues tested. However, a probe and STS developed from the DNA spanning the AK breakpoint is conserved in mouse, hamster and monkey, and we have detected expressed sequences in skin cells and cDNA libraries. In addition, unique sequences have been obtained from two CpG islands in the region that maps proximal to the breakpoints. cDNAs containing these sequences are being studied as candidates for the gene affected in the etiology of EDA.« less

Actinic keratosis modelling in mice: A translational study

PubMed Central

Vandenberghe, Isabelle; Cartron, Valérie; Cèbe, Patrick; Blanchet, Jean-Christophe; Sibaud, Vincent; Guilbaud, Nicolas; Audoly, Laurent; Lamant, Laurence; Kruczynski, Anna

2017-01-01

Background Actinic keratoses (AK) are pre-malignant cutaneous lesions caused by prolonged exposure to ultraviolet radiation. As AKs lesions are generally accepted to be the initial lesions in a disease continuum that progresses to squamous cell carcinoma (SCC), AK lesions have to be treated. They are also the second most common reason for visits to the dermatologist. Several treatments are available but their efficacy still needs to be improved. The UV-B-induced KA lesion mouse model is used in preclinical studies to assess the efficacy of novel molecules, even though it is often more representative of advanced AK or SCC. Objectives Here we report on a translational study, comparing the various stages of AK development in humans and in the UV-B irradiated mouse model, as well as the optimization of photograph acquisition of AK lesions on mouse skin. Methods Human and mouse skin lesions were analysed by histology and immunohistochemistry. Mouse lesions were also assessed using a digital dermatoscope. Results An histological and phenotypic analysis, including p53, Ki67 and CD3 expression detection, performed on human and mouse AK lesions, shows that overall AK modelling in mice is relevant in the clinical situation. Some differences are observed, such as disorganization of keratinocytes of the basal layer and a number of atypical nuclei which are more numerous in human AK, whereas much more pronounced acanthosis is observed in skin lesion in mice. Thanks to this translational study, we are able to select appropriate experimental conditions for establishing either early or advanced stage AK or an SCC model. Furthermore, we optimized photograph acquisition of AK lesions on mouse skin by using a digital dermatoscope which is also used in clinics and allows reproducible photograph acquisition for further reliable assessment of mouse lesions. Use of this camera is illustrated through a pharmacological study assessing the activity of CARAC®. Conclusion These data demonstrate that this mouse model of UV-B-induced skin lesions is predictive for the identification of novel therapeutic treatments for both early and advanced stages of the disease. PMID:28662116

Taltirelin alleviates fatigue-like behavior in mouse models of cancer-related fatigue.

PubMed

Dougherty, John P; Wolff, Brian S; Cullen, Mary J; Saligan, Leorey N; Gershengorn, Marvin C

2017-10-01

Fatigue affects most cancer patients and has numerous potential causes, including cancer itself and cancer treatment. Cancer-related fatigue (CRF) is not relieved by rest, can decrease quality of life, and has no FDA-approved therapy. Thyrotropin-releasing hormone (TRH) has been proposed as a potential novel treatment for CRF, but its efficacy against CRF remains largely untested. Thus, we tested the TRH analog, taltirelin (TAL), in mouse models of CRF. To model fatigue, we used a mouse model of chemotherapy, a mouse model of radiation therapy, and mice bearing colon 26 carcinoma tumors. We used the treadmill fatigue test to assess fatigue-like behavior after treatment with TAL. Additionally, we used wild-type and TRH receptor knockout mice to determine which TRH receptor was necessary for the actions of TAL. Tumor-bearing mice displayed muscle wasting and all models caused fatigue-like behavior, with mice running a shorter distance in the treadmill fatigue test than controls. TAL reversed fatigue-like behavior in all three models and the mouse TRH 1 receptor was necessary for the effects of TAL. These data suggest that TAL may be useful in alleviating fatigue in all cancer patients and provide further support for evaluating TAL as a potential therapy for CRF in humans. Published by Elsevier Ltd.

MR images of mouse brain using clinical 3T MR scanner and 4CH-Mouse coil

NASA Astrophysics Data System (ADS)

Lim, Soo Mee; Park, Eun Mi; Lyoo, In Kyoon; Lee, Junghyun; Han, Bo Mi; Lee, Jeong Kyong; Lee, Su Bin

2015-07-01

Objectives: Although small-bore high-field magnets are useful for research in small rodent models,this technology, however, has not been easily accessible to most researchers. This current study, thus,tried to evaluate the usability of 4CH-Mouse coil (Philips Healthcare, Best, the Netherlands) forpreclinical investigations in clinical 3T MR scan environment. We evaluated the effects of ischemicpreconditioning (IP) in the mouse stroke model with clinical 3T MR scanner and 4CH-Mouse coil. Materials and Methods: Experiments were performed on male C57BL/6 mice that either received the IP or sham operation (control). Three different MR sequences including diffusion weighted images (DWI), T2-weighted images (T2WI), and fluid attenuated inversion recovery (FLAIR) were performed on the mouse brains following 24, 72 hours of middle cerebral artery occlusion (MCAO) and analyzed for infarct lesions. Results: The images showed that the IP-treated mouse brains had significantly smaller infarct volumes compared to the control group. Of the MR sequences employed, the T2WI showed the highest level of correlations with postmortem infarct volume measurements. Conclusions: The clinical 3T MR scanner turned out to have a solid potential as a practical tool for imaging small animal brains. MR sequences including DWI, T2WI, FLAIR were obtained with acceptable resolution and in a reasonable time constraint in evaluating a mouse stroke model brain.

Mutagenicity testing with transgenic mice. Part I: Comparison with the mouse bone marrow micronucleus test

PubMed Central

Wahnschaffe, U; Bitsch, A; Kielhorn, J; Mangelsdorf, I

2005-01-01

As part of a larger literature study on transgenic animals in mutagenicity testing, test results from the transgenic mutagenicity assays (lacI model; commercially available as the Big Blue® mouse, and the lacZ model; commercially available as the Muta™Mouse), were compared with the results on the same substances in the more traditional mouse bone marrow micronucleus test. 39 substances were found which had been tested in the micronucleus assay and in the above transgenic mouse systems. Although, the transgenic animal mutation assay is not directly comparable with the micronucleus test, because different genetic endpoints are examined: chromosome aberration versus gene mutation, the results for the majority of substances were in agreement. Both test systems, the transgenic mouse assay and the mouse bone marrow micronucleus test, have advantages and they complement each other. However, the transgenic animal assay has some distinct advantages over the micronucleus test: it is not restricted to one target organ and detects systemic as well as local mutagenic effects. PMID:15655069

Phenotypic differences between BCG vaccines at the proteome level.

PubMed

Rodríguez-Alvarez, Mauricio; Mendoza-Hernández, Guillermo; Encarnación, Sergio; Calva, Juan José; López-Vidal, Yolanda

2009-03-01

To contribute to Mycobacterium bovis BCG characterization, two substrains were analyzed using two-dimensional gel electrophoresis (2D-PAGE) and mass spectrometry (MS), based on their protective efficacy in a pulmonary-tuberculosis mouse model. Cell-fraction proteins of BCG Denmark and Phipps substrains were separated into approximately 500 spots in 2D-PAGE. The proteomes were similar in protein number, and isoelectric point (pI) and molecular mass (MM) distribution. Statistical analysis, resulted in 72 spots with no change, and 168 and 90 unique for BCG Phipps or Denmark, respectively. Two hundred and fourteen spots showed changes in intensity of >1-fold, 138 of Denmark, and 76 of Phipps. Seventeen spots were selected for MS-based identification (13 from Phipps and 4 from Denmark), including unique, as well as proteins with changes in intensity. The proteins identified participate in virulence, detoxification, adaptation, lipid metabolism, information pathways, cell wall and cell processes, intermediary metabolism and respiration, or still hypotheticals. Our findings contribute to phenotype characterization of BCG substrains and provide new elements to consider for the design of diagnostic tools, drug targets and a new vaccine against tuberculosis based upon protein expression through quantitative statistical analysis.

In vivo characterization of a bigenic fluorescent mouse model of Alzheimer's disease with neurodegeneration.

PubMed

Crowe, Sarah E; Ellis-Davies, Graham C R

2013-07-01

The loss of cognitive function in Alzheimer's disease (AD) patients is strongly correlated with the loss of neurons in various regions of the brain. We have created a new fluorescent bigenic mouse model of AD by crossing "H-line" yellow fluorescent protein (YFP) mice with the 5xFAD mouse model, which we call the 5XY mouse model. The 5xFAD mouse has been shown to have significant loss of L5 pyramidal neurons by 12 months of age. These neurons are transgenically labeled with YFP in the 5XY mouse, which enable longitudinal imaging of structural changes. In the 5XY mice, we observed an appearance of axonal dystrophies, with two distinct morphologies in the early stages of the disease progression. Simple swelling dystrophies are transient in nature and are not directly associated with amyloid plaques. Rosette dystrophies are more complex structures that remained stable throughout all imaging sessions, and always surrounded an amyloid plaque. Plaque growth was followed over 4 weeks, and significant growth was seen between weekly imaging sessions. In addition to axonal dystrophy appearance and plaque growth, we were able to follow spine stability in 4-month old 5XY mice, which revealed no significant loss of spines. 5XY mice also showed a striking shrinkage of the neocortex at older ages (12-14 months). The 5XY mouse model may be a valuable tool for studying specific events in the degeneration of the neocortex, and may suggest new avenues for therapeutic intervention. Copyright © 2013 Wiley Periodicals, Inc.

Technique Selectively Represses Immune System

MedlinePlus

... from attacking myelin in a mouse model of multiple sclerosis. Dr David Furness, Wellcome Images. All rights reserved ... devised a way to successfully treat symptoms resembling multiple sclerosis in a mouse model. With further development, the ...

Lipopolysaccharide-induced endotoxemia in corn oil-preloaded mice causes an extended course of lung injury and repair and pulmonary fibrosis: A translational mouse model of acute respiratory distress syndrome.

PubMed

Wu, Chaomin; Evans, Colin E; Dai, Zhiyu; Huang, Xiaojia; Zhang, Xianming; Jin, Hua; Hu, Guochang; Song, Yuanlin; Zhao, You-Yang

2017-01-01

Acute respiratory distress syndrome (ARDS) is characterized by acute hypoxemia respiratory failure, bilateral pulmonary infiltrates, and pulmonary edema of non-cardiac origin. Effective treatments for ARDS patients may arise from experimental studies with translational mouse models of this disease that aim to delineate the mechanisms underlying the disease pathogenesis. Mouse models of ARDS, however, can be limited by their rapid progression from injured to recovery state, which is in contrast to the course of ARDS in humans. Furthermore, current mouse models of ARDS do not recapitulate certain prominent aspects of the pathogenesis of ARDS in humans. In this study, we developed an improved endotoxemic mouse model of ARDS resembling many features of clinical ARDS including extended courses of injury and recovery as well as development of fibrosis following i.p. injection of lipopolysaccharide (LPS) to corn oil-preloaded mice. Compared with mice receiving LPS alone, those receiving corn oil and LPS exhibited extended course of lung injury and repair that occurred over a period of >2 weeks instead of 3-5days. Importantly, LPS challenge of corn oil-preloaded mice resulted in pulmonary fibrosis during the repair phase as often seen in ARDS patients. In summary, this simple novel mouse model of ARDS could represent a valuable experimental tool to elucidate mechanisms that regulate lung injury and repair in ARDS patients.

Endometrial apoptosis and neutrophil infiltration during menstruation exhibits spatial and temporal dynamics that are recapitulated in a mouse model.

PubMed

Armstrong, Gregory M; Maybin, Jacqueline A; Murray, Alison A; Nicol, Moira; Walker, Catherine; Saunders, Philippa T K; Rossi, Adriano G; Critchley, Hilary O D

2017-12-12

Menstruation is characterised by synchronous shedding and restoration of tissue integrity. An in vivo model of menstruation is required to investigate mechanisms responsible for regulation of menstrual physiology and to investigate common pathologies such as heavy menstrual bleeding (HMB). We hypothesised that our mouse model of simulated menstruation would recapitulate the spatial and temporal changes in the inflammatory microenvironment of human menses. Three regulatory events were investigated: cell death (apoptosis), neutrophil influx and cytokine/chemokine expression. Well-characterised endometrial tissues from women were compared with uteri from a mouse model (tissue recovered 0, 4, 8, 24 and 48 h after removal of a progesterone-secreting pellet). Immunohistochemistry for cleaved caspase-3 (CC3) revealed significantly increased staining in human endometrium from late secretory and menstrual phases. In mice, CC3 was significantly increased at 8 and 24 h post-progesterone-withdrawal. Elastase + human neutrophils were maximal during menstruation; Ly6G + mouse neutrophils were maximal at 24 h. Human endometrial and mouse uterine cytokine/chemokine mRNA concentrations were significantly increased during menstrual phase and 24 h post-progesterone-withdrawal respectively. Data from dated human samples revealed time-dependent changes in endometrial apoptosis preceding neutrophil influx and cytokine/chemokine induction during active menstruation. These dynamic changes were recapitulated in the mouse model of menstruation, validating its use in menstrual research.

Plasmodium vivax liver stage development and hypnozoite persistence in human liver-chimeric mice

PubMed Central

Mikolajczak, Sebastian A.; Vaughan, Ashley M.; Kangwanrangsan, Niwat; Roobsoong, Wanlapa; Fishbaugher, Matthew; Yimamnuaychok, Narathatai; Rezakhani, Nastaran; Lakshmanan, Viswanathan; Singh, Naresh; Kaushansky, Alexis; Camargo, Nelly; Baldwin, Michael; Lindner, Scott E.; Adams, John H.; Prachumsri, Jetsumon; Kappe, Stefan H.I.

2017-01-01

Plasmodium vivax malaria is characterized by periodic relapses of symptomatic blood stage parasite infections likely initiated by activation of dormant liver stage parasites -hypnozoites. The lack of tractable animal models for P. vivax constitutes a severe obstacle to investigate this unique aspect of its biology and to test drug efficacy against liver stages. We show that the FRG KO huHep liver-humanized mice support P. vivax sporozoite infection, development of liver stages, and the formation of small non-replicating hypnozoites. Cellular characterization of P. vivax liver stage development in vivo demonstrates complete maturation into infectious exo-erythrocytic merozoites and continuing persistence of hypnozoites. Primaquine prophylaxis or treatment prevents and eliminates liver stage infection. Thus, the P. vivax/FRG KO huHep mouse infection model constitutes an important new tool to investigate the biology of liver stage development and dormancy and might aid in the discovery of new drugs for the prevention of relapsing malaria. PMID:25800544

The STR/ort mouse model of spontaneous osteoarthritis - an update.

PubMed

Staines, K A; Poulet, B; Wentworth, D N; Pitsillides, A A

2017-06-01

Osteoarthritis is a degenerative joint disease and a world-wide healthcare burden. Characterized by cartilage degradation, subchondral bone thickening and osteophyte formation, osteoarthritis inflicts much pain and suffering, for which there are currently no disease-modifying treatments available. Mouse models of osteoarthritis are proving critical in advancing our understanding of the underpinning molecular mechanisms. The STR/ort mouse is a well-recognized model which develops a natural form of osteoarthritis very similar to the human disease. In this Review we discuss the use of the STR/ort mouse in understanding this multifactorial disease with an emphasis on recent advances in its genetics and its bone, endochondral and immune phenotypes. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mouse brain magnetic resonance microscopy: Applications in Alzheimer disease.

PubMed

Lin, Lan; Fu, Zhenrong; Xu, Xiaoting; Wu, Shuicai

2015-05-01

Over the past two decades, various Alzheimer's disease (AD) trangenetic mice models harboring genes with mutation known to cause familial AD have been created. Today, high-resolution magnetic resonance microscopy (MRM) technology is being widely used in the study of AD mouse models. It has greatly facilitated and advanced our knowledge of AD. In this review, most of the attention is paid to fundamental of MRM, the construction of standard mouse MRM brain template and atlas, the detection of amyloid plaques, following up on brain atrophy and the future applications of MRM in transgenic AD mice. It is believed that future testing of potential drugs in mouse models with MRM will greatly improve the predictability of drug effect in preclinical trials. © 2015 Wiley Periodicals, Inc.

Better Utilization of Mouse Models of Neurodegenerative Diseases in Preclinical Studies: From the Bench to the Clinic.

PubMed

Janus, Christopher; Hernandez, Carolina; deLelys, Victoria; Roder, Hanno; Welzl, Hans

2016-01-01

The major symptom of Alzheimer's disease is dementia progressing with age. Its clinical diagnosis is preceded by a long prodromal period of brain pathology that encompasses both formation of extracellular amyloid and intraneuronal tau deposits in the brain and widespread neuronal death. At present, familial cases of dementia provide the most promising foundation for modeling neurodegenerative tauopathies, a group of heterogeneous disorders characterized by prominent intracellular accumulation of hyperphosphorylated tau protein. In this chapter, we describe major behavioral hallmarks of tauopathies, briefly outline the genetics underlying familial cases, and discuss the arising implications for modeling the disease in transgenic mouse systems. The selection of tests performed to evaluate the phenotype of a model should be guided by the key behavioral hallmarks that characterize human disorder and their homology to mouse cognitive systems. We attempt to provide general guidelines and establish criteria for modeling dementia in a mouse; however, interpretations of obtained results should avoid a reductionist "one gene, one disease" explanation of model characteristics. Rather, the focus should be directed to the question of how the mouse genome can cope with the over-expression of the protein coded by transgene(s). While each model is valuable within its own constraints and the experiments performed are guided by specific hypotheses, we seek to expand upon their methodology by offering guidance spanning from issues of mouse husbandry to choices of behavioral tests and routes of drug administration that might increase the external validity of studies and consequently optimize the translational aspect of preclinical research.

Rodent models of congenital and hereditary cataract in man.

PubMed

Tripathi, B J; Tripathi, R C; Borisuth, N S; Dhaliwal, R; Dhaliwal, D

1991-01-01

Because the organogenesis and physiology of the lens are essentially similar in various mammals, an understanding of the etiology and pathogenesis of the formation of cataract in an animal model will enhance our knowledge of cataractogenesis in man. In this review, we summarize the background, etiology, and pathogenesis of cataracts that occur in rodents. The main advantages of using rodent mutants include the well-researched genetics of the animals and the comparative ease of breeding of large litters. Numerous rodent models of congenital and hereditary cataracts have been studied extensively. In mice, the models include the Cts strain, Fraser mouse, lens opacity gene (Lop) strain, Lop-2 and Lop-3 strains, Philly mouse, Nakano mouse, Nop strain, Deer mouse, Emory mouse, Swiss Webster strain, Balb/c-nct/nct mouse, and SAM-R/3 strain. The rat models include BUdR, ICR, Sprague-Dawley, and Wistar rats, the spontaneously hypertensive rat (SHR), the John Rapp inbred strain of Dahl salt-sensitive rat, as well as WBN/Kob, Royal College of Surgeons (RCS), and Brown-Norway rats. Other proposed models for the study of hereditary cataract include the degu and the guinea pig. Because of the ease of making clinical observations in vivo and the subsequent availability of the intact lens for laboratory analyses at different stages of cataract formation, these animals provide excellent models for clinicopathologic correlations, for monitoring of the natural history of the aging process and of metabolic defects, as well as for investigations on the effect of cataract-modulating agents and drugs, including the prospect of gene therapy.

Gasdermin (Gsdm) localizing to mouse Chromosome 11 is predominantly expressed in upper gastrointestinal tract but significantly suppressed in human gastric cancer cells.

PubMed

Saeki, N; Kuwahara, Y; Sasaki, H; Satoh, H; Shiroishi, T

2000-09-01

Amplification of proto-oncogenes associated with their over-expression is one of the critical carcinogenic events identified in human cancer cells. In many cases of human gastric cancer, a proto-oncogene ERBB-2 is co-amplified with CAB1 genes physically linked to ERBB-2, and both genes are over-expressed. The amplified region containing ERBB-2 and CAB1 was named 17q12 amplicon from its chromosomal location. The syntenic region corresponding to the 17q12 amplicon is well conserved in mouse. In this study we isolated and characterized a novel mouse gene that locates telomeric to the mouse syntenic region. Northern blot analysis using the mouse cDNA and a cloned partial cDNA of human homolog disclosed a unique expression pattern of the genes. They are expressed predominantly in the gastrointestinal (GI) tract and in the skin at a lower level. Moreover, in the GI tract, the expression is highly restricted to the esophagus and stomach. Thus, we named the mouse gene Gasdermin (Gsdm). This is the first report of a mammalian gene whose expression is restricted to both upper GI tract and skin. Interestingly, in spite of its expression in normal stomach, no transcript was detected by Northern blot analysis in human gastric cancer cells. These data suggest that the loss of the expression of the human homolog is required for the carcinogenesis of gastric tissue and that the gene has an activity adverse to malignant transformation of cells.

Variation in umami perception and in candidate genes for the umami receptor in mice and humans1234

PubMed Central

Shirosaki, Shinya; Ohkuri, Tadahiro; Sanematsu, Keisuke; Islam, AA Shahidul; Ogiwara, Yoko; Kawai, Misako; Yoshida, Ryusuke; Ninomiya, Yuzo

2009-01-01

The unique taste induced by monosodium glutamate is referred to as umami taste. The umami taste is also elicited by the purine nucleotides inosine 5′-monophosphate and guanosine 5′-monophosphate. There is evidence that a heterodimeric G protein–coupled receptor, which consists of the T1R1 (taste receptor type 1, member 1, Tas1r1) and the T1R3 (taste receptor type 1, member 3, Tas1r3) proteins, functions as an umami taste receptor for rodents and humans. Splice variants of metabotropic glutamate receptors, mGluR1 (glutamate receptor, metabotropic 1, Grm1) and mGluR4 (glutamate receptor, metabotropic 4, Grm4), also have been proposed as taste receptors for glutamate. The taste sensitivity to umami substances varies in inbred mouse strains and in individual humans. However, little is known about the relation of umami taste sensitivity to variations in candidate umami receptor genes in rodents or in humans. In this article, we summarize current knowledge of the diversity of umami perception in mice and humans. Furthermore, we combine previously published data and new information from the single nucleotide polymorphism databases regarding variation in the mouse and human candidate umami receptor genes: mouse Tas1r1 (TAS1R1 for human), mouse Tas1r3 (TAS1R3 for human), mouse Grm1 (GRM1 for human), and mouse Grm4 (GRM4 for human). Finally, we discuss prospective associations between variation of these genes and umami taste perception in both species. PMID:19625681

Studies of Cell-Mediated Immunity Against Immune Disorders Using Synthetic Peptides and Rotating Bioreactor System

NASA Technical Reports Server (NTRS)

Sastry, Jagannadha K.

1998-01-01

We conducted a series of experiments using mouse immune-precursor cells, and observed that bioreactor culturing results in the loss of antigen-specific cytotoxic T lymphocyte (CTL) function. The reason for the abrogation of CTL function is microgravity conditions in the bioreactor, but not the antigen per se or its MHC restriction. Similarly, we observed that allostimulation of human PBMC in the bioreactor, but not in the T flask, resulted in the blunting of both allo-CTL function and the NK activity, indicating that the microgravity-associated functional defects are not unique to the mouse system. These results provide further confirmation to the microgravity-associated immune dysfunction, and constitute ground-based confirmatory data for those related to space-travel.

In vivo label-free photoacoustic microscopy of the anterior segment of the mouse eye

NASA Astrophysics Data System (ADS)

Rao, Bin; Hu, Song; Li, Li; Maslov, Konstantin; Wang, Lihong V.

2010-02-01

Both iris fluorescein angiography (IFA) and indocyanine green angiography (ICGA) provide ophthalmologists imaging tools in studying the microvasculature structure and hemodynamics of the anterior segment of the eye in normal and diseased status. However, a non-invasive, endogenous imaging modality is preferable for the monitoring of hemodynamics of the iris microvasculature. We investigated the in vivo, label-free ocular anterior segment imaging with photo-acoustic microscopy (PAM) in mouse eyes. We demonstrated the unique advantage of endogenous contrast that is not available in both IFA and ICGA. The laser radiation was maintained within the ANSI laser safety limit. The in vivo, label-free nature of our imaging technology has the potential for ophthalmic applications.

Mouse Genome Informatics (MGI) Is the International Resource for Information on the Laboratory Mouse.

PubMed

Law, MeiYee; Shaw, David R

2018-01-01

Mouse Genome Informatics (MGI, http://www.informatics.jax.org/ ) web resources provide free access to meticulously curated information about the laboratory mouse. MGI's primary goal is to help researchers investigate the genetic foundations of human diseases by translating information from mouse phenotypes and disease models studies to human systems. MGI provides comprehensive phenotypes for over 50,000 mutant alleles in mice and provides experimental model descriptions for over 1500 human diseases. Curated data from scientific publications are integrated with those from high-throughput phenotyping and gene expression centers. Data are standardized using defined, hierarchical vocabularies such as the Mammalian Phenotype (MP) Ontology, Mouse Developmental Anatomy and the Gene Ontologies (GO). This chapter introduces you to Gene and Allele Detail pages and provides step-by-step instructions for simple searches and those that take advantage of the breadth of MGI data integration.

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.

A Reverse-Translational Approach to Bipolar Disorder: Rodent and human studies in the Behavioral Pattern Monitor

PubMed Central

Young, Jared W.; Minassian, Arpi; Paulus, Martin P.; Geyer, Mark A.; Perry, William

2007-01-01

Mania is the defining feature of Bipolar Disorder (BD). There has been limited progress in understanding the neurobiological underpinnings of BD mania and developing novel therapeutics, in part due to a paucity of relevant animal models with translational potential. Hyperactivity is a cardinal symptom of mania, traditionally measured in humans using observer-rated scales. Multivariate assessment of unconditioned locomotor behavior using the rat Behavioral Pattern Monitor (BPM) developed in our laboratory has shown that hyperactivity includes complex multifaceted behaviors. The BPM has been used to demonstrate differential effects of drugs on locomotor activity and exploratory behavior in rats. Studies of genetically engineered mice in a mouse BPM have confirmed its utility as a cross-species tool. In a “reverse-translational” approach to this work, we developed the human BPM to characterize motor activity in BD patients. Increased activity, object interactions, and altered locomotor patterns provide multidimensional phenotypes to model in the rodent BPM. This unique approach to modeling BD provides an opportunity to identify the neurobiology underlying BD mania and test novel antimanic agents. PMID:17706782

Current State of Animal (Mouse) Modeling in Melanoma Research.

PubMed

Kuzu, Omer F; Nguyen, Felix D; Noory, Mohammad A; Sharma, Arati

2015-01-01

Despite the considerable progress in understanding the biology of human cancer and technological advancement in drug discovery, treatment failure remains an inevitable outcome for most cancer patients with advanced diseases, including melanoma. Despite FDA-approved BRAF-targeted therapies for advanced stage melanoma showed a great deal of promise, development of rapid resistance limits the success. Hence, the overall success rate of melanoma therapy still remains to be one of the worst compared to other malignancies. Advancement of next-generation sequencing technology allowed better identification of alterations that trigger melanoma development. As development of successful therapies strongly depends on clinically relevant preclinical models, together with the new findings, more advanced melanoma models have been generated. In this article, besides traditional mouse models of melanoma, we will discuss recent ones, such as patient-derived tumor xenografts, topically inducible BRAF mouse model and RCAS/TVA-based model, and their advantages as well as limitations. Although mouse models of melanoma are often criticized as poor predictors of whether an experimental drug would be an effective treatment, development of new and more relevant models could circumvent this problem in the near future.

An Embryonic and Induced Pluripotent Stem Cell Model for Ovarian Granulosa Cell Development and Steroidogenesis.

PubMed

Lipskind, Shane; Lindsey, Jennifer S; Gerami-Naini, Behzad; Eaton, Jennifer L; O'Connell, Daniel; Kiezun, Adam; Ho, Joshua W K; Ng, Nicholas; Parasar, Parveen; Ng, Michelle; Nickerson, Michael; Demirci, Utkan; Maas, Richard; Anchan, Raymond M

2018-05-01

Embryoid bodies (EBs) can serve as a system for evaluating pluripotency, cellular differentiation, and tissue morphogenesis. In this study, we use EBs derived from mouse embryonic stem cells (mESCs) and human amniocyte-derived induced pluripotent stem cells (hAdiPSCs) as a model for ovarian granulosa cell (GC) development and steroidogenic cell commitment. We demonstrated that spontaneously differentiated murine EBs (mEBs) and human EBs (hEBs) displayed ovarian GC markers, such as aromatase (CYP19A1), FOXL2, AMHR2, FSHR, and GJA1. Comparative microarray analysis identified both shared and unique gene expression between mEBs and the maturing mouse ovary. Gene sets related to gonadogenesis, lipid metabolism, and ovarian development were significantly overrepresented in EBs. Of the 29 genes, 15 that were differentially regulated in steroidogenic mEBs displayed temporal expression changes between embryonic, postnatal, and mature ovarian tissues by polymerase chain reaction. Importantly, both mEBs and hEBs were capable of gonadotropin-responsive estradiol (E2) synthesis in vitro (217-759 pg/mL). Live fluorescence-activated cell sorting-sorted AMHR2 + granulosa-like cells from mEBs continued to produce E2 after purification (15.3 pg/mL) and secreted significantly more E2 than AMHR2 - cells (8.6 pg/mL, P < .05). We conclude that spontaneously differentiated EBs of both mESC and hAdiPSC origin can serve as a biologically relevant model for ovarian GC differentiation and steroidogenic cell commitment. These cells should be further investigated for therapeutic uses, such as stem cell-based hormone replacement therapy and in vitro maturation of oocytes.

Multimodality optical coherence tomography and fluorescence confocal scanning laser ophthalmoscopy for image-guided feedback of intraocular injections in mouse models

NASA Astrophysics Data System (ADS)

Benavides, Oscar R.; Terrones, Benjamin D.; Leeburg, Kelsey C.; Mehanathan, Sankarathi B.; Levine, Edward M.; Tao, Yuankai K.

2018-02-01

Rodent models are robust tools for understanding human retinal disease and function because of their similarities with human physiology and anatomy and availability of genetic mutants. Optical coherence tomography (OCT) has been well-established for ophthalmic imaging in rodents and enables depth-resolved visualization of structures and image-based surrogate biomarkers of disease. Similarly, fluorescence confocal scanning laser ophthalmoscopy (cSLO) has demonstrated utility for imaging endogenous and exogenous fluorescence and scattering contrast in the mouse retina. Complementary volumetric scattering and en face fluorescence contrast from OCT and cSLO, respectively, enables cellular-resolution longitudinal imaging of changes in ophthalmic structure and function. We present a non-contact multimodal OCT+cSLO small animal imaging system with extended working distance to the pupil, which enables imaging during and after intraocular injection. While injections are routinely performed in mice to develop novel models of ophthalmic diseases and screen novel therapeutics, the location and volume delivered is not precisely controlled and difficult to reproduce. Animals were imaged using a custom-built OCT engine and scan-head combined with a modified commercial cSLO scan-head. Post-injection imaging showed structural changes associated with retinal puncture, including the injection track, a retinal elevation, and detachment of the posterior hyaloid. When combined with imagesegmentation, we believe OCT can be used to precisely identify injection locations and quantify injection volumes. Fluorescence cSLO can provide complementary contrast for either fluorescently labeled compounds or transgenic cells for improved specificity. Our non-contact OCT+cSLO system is uniquely-suited for concurrent imaging with intraocular injections, which may be used for real-time image-guided injections.

Efficacy of Alteplase® in a mouse model of acute ischemic stroke: a retrospective pooled analysis

PubMed Central

Orset, Cyrille; Haelewyn, Benoit; Allan, Stuart M.; Ansar, Saema; Campos, Francesco; Cho, Tae Hee; Durand, Anne; El Amki, Mohamad; Fatar, Marc; Garcia-Yébenes, Isaac; Gauberti, Maxime; Grudzenski, Saskia; Lizasoain, Ignacio; Lo, Eng; Macrez, Richard; Margaill, Isabelle; Maysami, Samaneh; Meairs, Stephen; Nighoghossian, Norbert; Orbe, Josune; Paramo, Jose Antonio; Parienti, Jean-Jacques; Rothwell, Nancy J.; Rubio, Marina; Waeber, Christian; Young, Alan R.

2016-01-01

Background and purpose The debate over the fact that experimental drugs proposed for the treatment of stroke fail in the translation to the clinical situation, has attracted considerable attention in the literature. In this context, we present a retrospective pooled analysis of a large dataset from pre-clinical studies, in order to examine the effects of early versus late administration of intravenous recombinant tissue type plasminogen activator (rt-PA). Methods We collected data from 26 individual studies from 9 international centers (13 researchers, 716 animals) that compared rt-PA to controls, in a unique mouse model of thromboembolic stroke induced by an in situ injection of thrombin into the middle cerebral artery. Studies were classified into early (<3h) versus late (≥3h) drug administration. Final infarct volumes, assessed by histology or MRI, were compared in each study and the absolute differences were pooled in a random-effect meta-analysis. The influence of time of administration was tested. Results When compared to saline controls, early rt-PA administration was associated with a significant benefit (absolute difference = −6.63 mm3; 95%CI, −9.08 to −4.17; I2=76%) whereas late rt-PA treatment showed a deleterious effect (+5.06 mm3; 95%CI, +2.78 to +7.34; I2=42%, Pint<0.00001). Results remained unchanged following subgroup analyses. Conclusion Our results provide the basis needed for the design of future pre-clinical studies on recanalization therapies using this model of thromboembolic stroke in mice. The power analysis reveals that a multi-center trial would require 123 animals per group instead of 40 for a single center trial. PMID:27032444

Transitional basal cells at the squamous-columnar junction generate Barrett’s oesophagus

PubMed Central

Jiang, Ming; Li, Haiyan; Zhang, Yongchun; Yang, Ying; Lu, Rong; Liu, Kuancan; Lin, Sijie; Lan, Xiaopeng; Wang, Haikun; Wu, Han; Zhu, Jian; Zhou, Zhongren; Xu, Jianming; Lee, Dong-Kee; Zhang, Lanjing; Lee, Yuan-Cho; Yuan, Jingsong; Abrams, Julian A.; Wang, Timothy G.; Sepulveda, Antonia R.; Wu, Qi; Chen, Huaiyong; Sun, Xin; She, Junjun; Chen, Xiaoxin; Que, Jianwen

2017-01-01

In several organ systems the transitional zone between different types of epithelia is a hotspot for pre-neoplastic metaplasia and malignancy1–3. However, the cell-of-origin for the metaplastic epithelium and subsequent malignancy, remains obscure1–3. In the case of Barrett’s oesophagus (BE), intestinal metaplasia occurs at the gastro-oesophageal junction, where stratified squamous epithelium transitions into simple columnar cells4. Based on different experimental models, several alternative cell types have been proposed as the source of the metaplasia, but in all cases the evidence is inconclusive and no model completely mimics BE with the presence of intestinal goblet cells5–8. Here, we describe a novel transitional columnar epithelium with distinct basal progenitor cells (p63+ KRT5+ KRT7+) in the squamous-columnar junction (SCJ) in the upper gastrointestinal tract of the mouse. We use multiple models and lineage tracing strategies to show that this unique SCJ basal cell population serves as a source of progenitors for the transitional epithelium. Moreover, upon ectopic expression of CDX2 these transitional basal progenitors differentiate into intestinal-like epithelium including goblet cells, thus reproducing Barrett’s metaplasia. A similar transitional columnar epithelium is present at the transitional zones of other mouse tissues, including the anorectal junction, and, importantly, at the gastro-oesophageal junction in the human gut. Acid reflux-induced oesophagitis and the multilayered epithelium (MLE) believed to be a precursor of BE are both characterized by the expansion of the transitional basal progenitor cells. Taken together our findings reveal the presence of a previously unidentified transitional zone in the epithelium of the upper gastrointestinal tract and provide evidence that the p63+ KRT7+ basal cells in this zone are the cell-of-origin for MLE and BE. PMID:29019984

Cortical functional hyperconnectivity in a mouse model of depression and selective network effects of ketamine.

PubMed

McGirr, Alexander; LeDue, Jeffrey; Chan, Allen W; Xie, Yicheng; Murphy, Timothy H

2017-08-01

See Huang and Liston (doi:10.1093/awx166) for a scientific commentary on this article.Human depression is associated with glutamatergic dysfunction and alterations in resting state network activity. However, the indirect nature of human in vivo glutamate and activity assessments obscures mechanistic details. Using the chronic social defeat mouse model of depression, we determine how mesoscale glutamatergic networks are altered after chronic stress, and in response to the rapid acting antidepressant, ketamine. Transgenic mice (Ai85) expressing iGluSnFR (a recombinant protein sensor) permitted real-time in vivo selective characterization of extracellular glutamate and longitudinal imaging of mesoscale cortical glutamatergic functional circuits. Mice underwent chronic social defeat or a control condition, while spontaneous cortical activity was longitudinally sampled. After chronic social defeat, we observed network-wide glutamate functional hyperconnectivity in defeated animals, which was confirmed with voltage sensitive dye imaging in an independent cohort. Subanaesthetic ketamine has unique effects in defeated animals. Acutely, subanaesthetic ketamine induces large global cortical glutamate transients in defeated animals, and an elevated subanaesthetic dose resulted in sustained global increase in cortical glutamate. Local cortical inhibition of glutamate transporters in naïve mice given ketamine produced a similar extracellular glutamate phenotype, with both glutamate transients and a dose-dependent accumulation of glutamate. Twenty-four hours after ketamine, normalization of depressive-like behaviour in defeated animals was accompanied by reduced glutamate functional connectivity strength. Altered glutamate functional connectivity in this animal model confirms the central role of glutamate dynamics as well as network-wide changes after chronic stress and in response to ketamine. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of the neuroactive steroid ganaxolone on social and repetitive behaviors in the BTBR mouse model of autism.

PubMed

Kazdoba, Tatiana M; Hagerman, Randi J; Zolkowska, Dorota; Rogawski, Michael A; Crawley, Jacqueline N

2016-01-01

Abnormalities in excitatory/inhibitory neurotransmission are hypothesized to contribute to autism spectrum disorder (ASD) etiology. BTBR T (+) Itpr3 (tf) /J (BTBR), an inbred mouse strain, displays social deficits and repetitive self-grooming, offering face validity to ASD diagnostic symptoms. Reduced GABAergic neurotransmission in BTBR suggests that GABAA receptor positive allosteric modulators (PAMs) could improve ASD-relevant BTBR phenotypes. The neuroactive steroid ganaxolone acts as a PAM, displaying anticonvulsant properties in rodent epilepsy models and an anxiolytic-like profile in the elevated plus-maze. We evaluated ganaxolone in BTBR and C57BL/6J mice in standardized assays for sociability and repetitive behaviors. Open field and anxiety-related behaviors were tested as internal controls and for comparison with the existing neuroactive steroid literature. Ganaxolone improved aspects of social approach and reciprocal social interactions in BTBR, with no effect on repetitive self-grooming, and no detrimental effects in C57BL/6J. Ganaxolone increased overall exploratory activity in BTBR and C57BL/6J in the open field, social approach, and elevated plus-maze, introducing a confound for the interpretation of social improvements. Allopregnanolone and diazepam similarly increased total entries in the elevated plus-maze, indicating that behavioral activation may be a general property of GABAA receptor PAMs in these strains. Ganaxolone shows promise for improving sociability. In addition, ganaxolone, as well as other GABAA receptor PAMs, enhanced overall BTBR activity. The translational implications of specific sociability improvements and nonspecific behavioral activation by ganaxolone in the BTBR model remain to be determined. Future studies to explore whether PAMs provide a novel profile with unique benefits for ASD treatment will be worthwhile.

Evaluation of the neuroactive steroid ganaxolone on social and repetitive behaviors in the BTBR mouse model of autism

PubMed Central

Kazdoba, Tatiana M.; Hagerman, Randi J.; Zolkowska, Dorota; Rogawski, Michael A.; Crawley, Jacqueline N.

2015-01-01

Rationale Abnormalities in excitatory/inhibitory neurotransmission are hypothesized to contribute to autism spectrum disorder (ASD) etiology. BTBR, an inbred mouse strain, displays social deficits and repetitive self-grooming, offering face validity to ASD diagnostic symptoms. Reduced GABAergic neurotransmission in BTBR suggests that GABAA receptor positive allosteric modulators (PAMs) could improve ASD-relevant BTBR phenotypes. The neuroactive steroid ganaxolone acts as a PAM, displaying anticonvulsant properties in rodent epilepsy models and an anxiolytic-like profile in the elevated plus-maze. Objectives We evaluated ganaxolone in BTBR and C57BL/6J mice in standardized assays for sociability and repetitive behaviors. Open field and anxiety-related behaviors were tested as internal controls and for comparison with the existing neuroactive steroid literature. Results Ganaxolone improved aspects of social approach and reciprocal social interactions in BTBR, with no effect on repetitive self-grooming, and no detrimental effects in C57BL/6J. Ganaxolone increased overall exploratory activity in BTBR and C57BL/6J in the open field, social approach, and elevated plus-maze, introducing a confound for the interpretation of social improvements. Allopregnanolone and diazepam similarly increased total entries in the elevated plus-maze, indicating that behavioral activation may be a general property of GABAA receptor PAMs in these strains. Conclusions Ganaxolone shows promise for improving sociability. In addition, ganaxolone, as well as other GABAA receptor PAMs, enhanced overall BTBR activity. The translational implications of specific sociability improvements and non-specific behavioral activation by ganaxolone in the BTBR model remains to be determined. Future studies to explore whether PAMs provide a novel profile with unique benefits for ASD treatment will be worthwhile. PMID:26525567

Behavioral and Neurobiological Effects of Deep Brain Stimulation in a Mouse Model of High Anxiety- and Depression-Like Behavior

PubMed Central

Schmuckermair, Claudia; Gaburro, Stefano; Sah, Anupam; Landgraf, Rainer; Sartori, Simone B; Singewald, Nicolas

2013-01-01

Increasing evidence suggests that high-frequency deep brain stimulation of the nucleus accumbens (NAcb-DBS) may represent a novel therapeutic strategy for individuals suffering from treatment-resistant depression, although the underlying mechanisms of action remain largely unknown. In this study, using a unique mouse model of enhanced depression- and anxiety-like behavior (HAB), we investigated behavioral and neurobiological effects of NAcb-DBS. HAB mice either underwent chronic treatment with one of three different selective serotonin reuptake inhibitors (SSRIs) or received NAcb-DBS for 1 h per day for 7 consecutive days. Animals were tested in established paradigms revealing depression- and anxiety-related behaviors. The enhanced depression-like behavior of HAB mice was not influenced by chronic SSRI treatment. In contrast, repeated, but not single, NAcb-DBS induced robust antidepressant and anxiolytic responses in HAB animals, while these behaviors remained unaffected in normal depression/anxiety animals (NAB), suggesting a preferential effect of NAcb-DBS on pathophysiologically deranged systems. NAcb-DBS caused a modulation of challenge-induced activity in various stress- and depression-related brain regions, including an increase in c-Fos expression in the dentate gyrus of the hippocampus and enhanced hippocampal neurogenesis in HABs. Taken together, these findings show that the normalization of the pathophysiologically enhanced, SSRI-insensitive depression-like behavior by repeated NAcb-DBS was associated with the reversal of reported aberrant brain activity and impaired adult neurogenesis in HAB mice, indicating that NAcb-DBS affects neuronal activity as well as plasticity in a defined, mood-associated network. Thus, HAB mice may represent a clinically relevant model for elucidating the neurobiological correlates of NAcb-DBS. PMID:23325324

Anti-amyloid beta to tau - based immunization: Developments in immunotherapy for Alzheimer disease.

PubMed

Lambracht-Washington, Doris; Rosenberg, Roger N

2013-08-01

Immunotherapy might provide an effective treatment for Alzheimer disease (AD). A unique feature of AD immunotherapies is that an immune response against a self antigen needs to be elicited without causing adverse autoimmune reactions. Current research is focussed on two possible targets in this regard: One is the inhibition of accumulation and deposition of Amyloid beta 1-42 (Aβ42), which is one of the major peptides found in senile plaques and the second target is hyperphosphorylated tau, which forms neurofibrillary tangles inside the nerve cell and shows association with the progression of dementia. Mouse models have shown that immunotherapy targeting Aβ42 as well as tau with the respective anti-Aβ or anti-tau antibodies can provide significant improvements in these mice. While anti-Aβ immunotherapy (active and passive immunizations) is already in several stages of clinical trials, tau based immunizations have been analyzed only in mouse models. Recently, as a significant correlation of progression of dementia and levels of phoshorylated tau was found, high interest has again focussed on further development of tau based therapies. While Aβ immunotherapy might delay the onset of AD, immunotherapy targeting tau might provide benefits in later stages of this disease. And last but not least, targeting Aβ and tau simultaneously with immunotherapy might provide additional therapeutic effects as these two pathologies are likely synergistic; an approach which has not been tested yet. In this review, we will summarize animal models used to test possible therapies for AD, some of the facts about Aβ42 and tau biology, present on overview on halted, ongoing and upcoming clinical trials together with ongoing preclinical studies targeting tau or Aβ42.

Low-Dose Alkylphenol Exposure Promotes Mammary Epithelium Alterations and Transgenerational Developmental Defects, But Does Not Enhance Tumorigenic Behavior of Breast Cancer Cells

PubMed Central

Chamard-Jovenin, Clémence; Thiebaut, Charlène; Chesnel, Amand; Bresso, Emmanuel; Morel, Chloé; Smail-Tabbone, Malika; Devignes, Marie-Dominique; Boukhobza, Taha; Dumond, Hélène

2017-01-01

Fetal and neonatal exposure to long-chain alkylphenols has been suspected to promote breast developmental disorders and consequently to increase breast cancer risk. However, disease predisposition from developmental exposures remains unclear. In this work, human MCF-10A mammary epithelial cells were exposed in vitro to a low dose of a realistic (4-nonylphenol + 4-tert-octylphenol) mixture. Transcriptome and cell-phenotype analyses combined to functional and signaling network modeling indicated that long-chain alkylphenols triggered enhanced proliferation, migration ability, and apoptosis resistance and shed light on the underlying molecular mechanisms which involved the human estrogen receptor alpha 36 (ERα36) variant. A male mouse-inherited transgenerational model of exposure to three environmentally relevant doses of the alkylphenol mix was set up in order to determine whether and how it would impact on mammary gland architecture. Mammary glands from F3 progeny obtained after intrabuccal chronic exposure of C57BL/6J P0 pregnant mice followed by F1–F3 male inheritance displayed an altered histology which correlated with the phenotypes observed in vitro in human mammary epithelial cells. Since cellular phenotypes are similar in vivo and in vitro and involve the unique ERα36 human variant, such consequences of alkylphenol exposure could be extrapolated from mouse model to human. However, transient alkylphenol treatments combined to ERα36 overexpression in mammary epithelial cells were not sufficient to trigger tumorigenesis in xenografted Nude mice. Therefore, it remains to be determined if low-dose alkylphenol transgenerational exposure and subsequent abnormal mammary gland development could account for an increased breast cancer susceptibility. PMID:29109696