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Articles 1 - 30 of 50
Full-Text Articles in Life Sciences
Genetic And Acute Cpeb1 Depletion Ameliorate Fragile X Pathophysiology, Tsuyoshi Udagawa, Natalie Farny, Mira Jakovcevski, Hanoch Kaphzan, Juan Alarcon, Shobha Anilkumar, Maria Ivshina, Jessica Hurt, Kentaro Nagaoka, Vijayalaxmi Nalavadi, Lori Lorenz, Gary Bassell, Schahram Akbarian, Sumantra Chattarji, Eric Klann, Joel Richter
Genetic And Acute Cpeb1 Depletion Ameliorate Fragile X Pathophysiology, Tsuyoshi Udagawa, Natalie Farny, Mira Jakovcevski, Hanoch Kaphzan, Juan Alarcon, Shobha Anilkumar, Maria Ivshina, Jessica Hurt, Kentaro Nagaoka, Vijayalaxmi Nalavadi, Lori Lorenz, Gary Bassell, Schahram Akbarian, Sumantra Chattarji, Eric Klann, Joel Richter
Natalie G. Farny
Fragile X syndrome (FXS), the most common cause of inherited mental retardation and autism, is caused by transcriptional silencing of FMR1, which encodes the translational repressor fragile X mental retardation protein (FMRP). FMRP and cytoplasmic polyadenylation element-binding protein (CPEB), an activator of translation, are present in neuronal dendrites, are predicted to bind many of the same mRNAs and may mediate a translational homeostasis that, when imbalanced, results in FXS. Consistent with this possibility, Fmr1(-/y); Cpeb1(-/-) double-knockout mice displayed amelioration of biochemical, morphological, electrophysiological and behavioral phenotypes associated with FXS. Acute depletion of CPEB1 in the hippocampus of adult Fmr1(-/y) mice …
Substrate Rigidity Regulates The Formation And Maintenance Of Tissues, Wei-Hui Guo, Margo Frey, Nancy Burnham, Yu-Li Wang
Substrate Rigidity Regulates The Formation And Maintenance Of Tissues, Wei-Hui Guo, Margo Frey, Nancy Burnham, Yu-Li Wang
Nancy A. Burnham
The ability of cells to form tissues represents one of the most fundamental issues in biology. However, it is unclear what triggers cells to adhere to one another in tissues and to migrate once a piece of tissue is planted on culture surfaces. Using substrates of identical chemical composition but different flexibility, we show that this process is controlled by substrate rigidity: on stiff substrates, cells migrate away from one another and spread on surfaces, whereas on soft substrates they merge to form tissue-like structures. Similar behavior was observed not only with fibroblastic and epithelial cell lines but also explants …
Cd4+ Regulatory T Cells Require Ctla-4 For The Maintenance Of Systemic Tolerance, Randall Friedline, David Brown, Hai Nguyen, Hardy Kornfeld, Jinhee Lee, Yi Zhang, Mark Appleby, Sandy Der, Joonsoo Kang, Cynthia Chambers
Cd4+ Regulatory T Cells Require Ctla-4 For The Maintenance Of Systemic Tolerance, Randall Friedline, David Brown, Hai Nguyen, Hardy Kornfeld, Jinhee Lee, Yi Zhang, Mark Appleby, Sandy Der, Joonsoo Kang, Cynthia Chambers
David C. Brown
Cytotoxic T lymphocyte antigen-4 (CTLA-4) plays a critical role in negatively regulating T cell responses and has also been implicated in the development and function of natural FOXP3(+) regulatory T cells. CTLA-4-deficient mice develop fatal, early onset lymphoproliferative disease. However, chimeric mice containing both CTLA-4-deficient and -sufficient bone marrow (BM)-derived cells do not develop disease, indicating that CTLA-4 can act in trans to maintain T cell self-tolerance. Using genetically mixed blastocyst and BM chimaeras as well as in vivo T cell transfer systems, we demonstrate that in vivo regulation of Ctla4(-/-) T cells in trans by CTLA-4-sufficient T cells is …
A Conserved Three-Nucleotide Core Motif Defines Musashi Rna Binding Specificity, Nancy Zearfoss, Laura Deveau, Carina Clingman, Eric Schmidt, Emily Johnson, Francesca Massi, Sean Ryder
A Conserved Three-Nucleotide Core Motif Defines Musashi Rna Binding Specificity, Nancy Zearfoss, Laura Deveau, Carina Clingman, Eric Schmidt, Emily Johnson, Francesca Massi, Sean Ryder
Sean P. Ryder
Musashi (MSI) family proteins control cell proliferation and differentiation in many biological systems. They are overexpressed in tumors of several origins, and their expression level correlates with poor prognosis. MSI proteins control gene expression by binding RNA and regulating its translation. They contain two RNA recognition motif (RRM) domains, which recognize a defined sequence element. The relative contribution of each nucleotide to the binding affinity and specificity is unknown. We analyzed the binding specificity of three MSI family RRM domains using a quantitative fluorescence anisotropy assay. We found that the core element driving recognition is the sequence UAG. Nucleotides outside …
Allosteric Inhibition Of A Stem Cell Rna-Binding Protein By An Intermediary Metabolite, Carina Clingman, Laura Deveau, Samantha Hay, Ryan Genga, Shivender Shandilya, Francesca Massi, Sean Ryder
Allosteric Inhibition Of A Stem Cell Rna-Binding Protein By An Intermediary Metabolite, Carina Clingman, Laura Deveau, Samantha Hay, Ryan Genga, Shivender Shandilya, Francesca Massi, Sean Ryder
Sean P. Ryder
Gene expression and metabolism are coupled at numerous levels. Cells must sense and respond to nutrients in their environment, and specialized cells must synthesize metabolic products required for their function. Pluripotent stem cells have the ability to differentiate into a wide variety of specialized cells. How metabolic state contributes to stem cell differentiation is not understood. In this study, we show that RNA-binding by the stem cell translation regulator Musashi-1 (MSI1) is allosterically inhibited by 18-22 carbon omega-9 monounsaturated fatty acids. The fatty acid binds to the N-terminal RNA Recognition Motif (RRM) and induces a conformational change that prevents RNA …
Quaking Regulates Hnrnpa1 Expression Through Its 3' Utr In Oligodendrocyte Precursor Cells, Nancy Zearfoss, Carina Clingman, Brian Farley, Lisa Mccoig, Sean Ryder
Quaking Regulates Hnrnpa1 Expression Through Its 3' Utr In Oligodendrocyte Precursor Cells, Nancy Zearfoss, Carina Clingman, Brian Farley, Lisa Mccoig, Sean Ryder
Sean P. Ryder
In mice, Quaking (Qk) is required for myelin formation; in humans, it has been associated with psychiatric disease. QK regulates the stability, subcellular localization, and alternative splicing of several myelin-related transcripts, yet little is known about how QK governs these activities. Here, we show that QK enhances Hnrnpa1 mRNA stability by binding a conserved 3' UTR sequence with high affinity and specificity. A single nucleotide mutation in the binding site eliminates QK-dependent regulation, as does reduction of QK by RNAi. Analysis of exon expression across the transcriptome reveals that QK and hnRNP A1 regulate an overlapping subset of transcripts. Thus, …
Hnrnp A1 And Secondary Structure Coordinate Alternative Splicing Of Mag, Nancy Zearfoss, Emily Johnson, Sean Ryder
Hnrnp A1 And Secondary Structure Coordinate Alternative Splicing Of Mag, Nancy Zearfoss, Emily Johnson, Sean Ryder
Sean P. Ryder
Myelin-associated glycoprotein (MAG) is a major component of myelin in the vertebrate central nervous system. MAG is present in the periaxonal region of the myelin structure, where it interacts with neuronal proteins to inhibit axon outgrowth and protect neurons from degeneration. Two alternatively spliced isoforms of Mag mRNA have been identified. The mRNA encoding the shorter isoform, known as S-MAG, contains a termination codon in exon 12, while the mRNA encoding the longer isoform, known as L-MAG, skips exon 12 and produces a protein with a longer C-terminal region. L-MAG is required in the central nervous system. How inclusion of …
Argonaute Protein Identity And Pairing Geometry Determine Cooperativity In Mammalian Rna Silencing, Jennifer Broderick, William Salomon, Sean Ryder, Neil Aronin, Phillip Zamore
Argonaute Protein Identity And Pairing Geometry Determine Cooperativity In Mammalian Rna Silencing, Jennifer Broderick, William Salomon, Sean Ryder, Neil Aronin, Phillip Zamore
Sean P. Ryder
Small RNAs loaded into Argonaute proteins direct silencing of complementary target mRNAs. It has been proposed that multiple, imperfectly complementary small interfering RNAs or microRNAs, when bound to the 3' untranslated region of a target mRNA, function cooperatively to silence target expression. We report that, in cultured human HeLa cells and mouse embryonic fibroblasts, Argonaute1 (Ago1), Ago3, and Ago4 act cooperatively to silence both perfectly and partially complementary target RNAs bearing multiple small RNA-binding sites. Our data suggest that for Ago1, Ago3, and Ago4, multiple, adjacent small RNA-binding sites facilitate cooperative interactions that stabilize Argonaute binding. In contrast, small RNAs …
Post-Transcriptional Regulation Of Myelin Formation, Nancy Zearfoss, Brian Farley, Sean Ryder
Post-Transcriptional Regulation Of Myelin Formation, Nancy Zearfoss, Brian Farley, Sean Ryder
Sean P. Ryder
Myelin is a specialized structure of the nervous system that both enhances electrical conductance and protects neurons from degeneration. In the central nervous system, extensively polarized oligodendrocytes form myelin by wrapping cellular processes in a spiral pattern around neuronal axons. Myelin formation requires the oligodendrocyte to regulate gene expression in response to changes in its extracellular environment. Because these changes occur at a distance from the cell body, post-transcriptional control of gene expression allows the cell to fine-tune its response. Here, we review the RNA-binding proteins that control myelin formation in the brain, highlighting the molecular mechanisms by which they …
A Mutation In The Mouse Chd2 Chromatin Remodeling Enzyme Results In A Complex Renal Phenotype, Concetta Marfella, Nils Henninger, Scott Leblanc, Namrata Krishnan, David Garlick, Lawrence Holzman, Anthony Imbalzano
A Mutation In The Mouse Chd2 Chromatin Remodeling Enzyme Results In A Complex Renal Phenotype, Concetta Marfella, Nils Henninger, Scott Leblanc, Namrata Krishnan, David Garlick, Lawrence Holzman, Anthony Imbalzano
Nils Henninger
BACKGROUND AND AIMS: Glomerular diseases are the third leading cause of kidney failure worldwide, behind only diabetes and hypertension. The molecular mechanisms underlying the cause of glomerular diseases are still largely unknown. The identification and characterization of new molecules associated with glomerular function should provide new insights into understanding the diverse group of glomerular diseases. The Chd2 protein belongs to a family of enzymes involved in ATP-dependent chromatin remodeling, suggesting that it likely functions as an epigenetic regulator of gene expression via the modification of chromatin structure. METHODS: In this study, we present a detailed histomorphologic characterization of mice containing …
Pubertal And Adult Leydig Cell Function In Mullerian Inhibiting Substance-Deficient Mice, Xiufeng Wu, Ramamani Arumugam, Stephen Baker, Mary Lee
Pubertal And Adult Leydig Cell Function In Mullerian Inhibiting Substance-Deficient Mice, Xiufeng Wu, Ramamani Arumugam, Stephen Baker, Mary Lee
Mary M. Lee
Mullerian inhibiting substance (MIS) causes Mullerian duct regression during sexual differentiation and regulates postnatal Leydig cell development. MIS knockout (MIS-KO) mice with targeted deletions of MIS develop Leydig cell hyperplasia, but their circulating androgen concentrations are reportedly unaltered. We compared reproductive hormone profiles, androgen biosynthesis, and the expression of key steroidogenic and metabolic enzymes in MIS-KO and wild-type (WT) mice at puberty (36 d) and sexual maturity (60 d). In pubertal animals, basal testosterone and LH concentrations in plasma were lower in MIS-KO than WT mice, whereas human chorionic gonadotropin-stimulated testosterone concentrations were similar. In adults, basal LH, and both …
P19ink4d And P18ink4c Cyclin-Dependent Kinase Inhibitors In The Male Reproductive Axis, Gregory Buchold, Patricia Magyar, Ramamani Arumugam, Mary Lee, Deborah O'Brien
P19ink4d And P18ink4c Cyclin-Dependent Kinase Inhibitors In The Male Reproductive Axis, Gregory Buchold, Patricia Magyar, Ramamani Arumugam, Mary Lee, Deborah O'Brien
Mary M. Lee
The loss of the cyclin-dependent kinase inhibitors (CKIs) p18(Ink4c) and p19(Ink4d) leads to male reproductive defects (Franklin et al., 1998. Genes Dev 12: 2899-2911; Zindy et al., 2000. Mol Cell Biol 20: 372-378; Zindy et al., 2001. Mol Cell Biol 21: 3244-3255). In order to assess whether these inhibitors directly or indirectly affect male germ cell differentiation, we examined the expression of p18(Ink4c) and p19(Ink4d) in spermatogenic and supporting cells in the testis and in pituitary gonadotropes. Both p18(Ink4c) and p19(Ink4d) are most abundant in the testis after 18 days of age and are expressed in purified populations of spermatogenic …
Androgen Profiles During Pubertal Leydig Cell Development In Mice, Xiufeng Wu, Ramamani Arumugam, Ningning Zhang, Mary Lee
Androgen Profiles During Pubertal Leydig Cell Development In Mice, Xiufeng Wu, Ramamani Arumugam, Ningning Zhang, Mary Lee
Mary M. Lee
Postnatal Leydig cell (LC) development in mice has been assumed empirically to resemble that of rats, which have characteristic hormonal profiles at well-defined maturational stages. To characterize the changes in LC function and gene expression in mice, we examined reproductive hormone expression from birth to 180 days, and quantified in vivo and in vitro production of androgens during sexual maturation. Although the overall plasma androgen and LH profiles from birth through puberty were comparable to that of rats, the timing of developmental changes in androgen production and steroidogenic capacity of isolated LCs differed. In mice, onset of androgen biosynthetic capacity, …
Effect Of E. Coli Endotoxin On Mammalian Cell Growth And Recombinant Protein Production, J. Epstein, Mary Lee, C. Kelly, Patricia Donahoe
Effect Of E. Coli Endotoxin On Mammalian Cell Growth And Recombinant Protein Production, J. Epstein, Mary Lee, C. Kelly, Patricia Donahoe
Mary M. Lee
No abstract provided.
Multiple Specificities In The Murine Cd4+ And Cd8+ T-Cell Response To Dengue Virus, Alan Rothman, Ichiro Kurane, Francis Ennis
Multiple Specificities In The Murine Cd4+ And Cd8+ T-Cell Response To Dengue Virus, Alan Rothman, Ichiro Kurane, Francis Ennis
Alan Rothman
The target epitopes, serotype specificity, and cytolytic function of dengue virus-specific T cells may influence their theoretical roles in protection against secondary infection as well as the immunopathogenesis of dengue hemorrhagic fever. To study these factors in an experimental system, we isolated dengue virus-specific CD4+ and CD8+ T-cell clones from dengue-2 virus-immunized BALB/c mice. The T-cell response to dengue virus in this mouse strain was heterogeneous; we identified at least five different CD4+ phenotypes and six different CD8+ phenotypes. Individual T-cell clones recognized epitopes on the dengue virus pre-M, E, NSl/NS2A, and NS3 proteins and were restricted by the I-Ad, …
Cross-Reactive Memory Cd8(+) T Cells Alter The Immune Response To Heterologous Secondary Dengue Virus Infections In Mice In A Sequence-Specific Manner, Coreen Beaumier, Anuja Mathew, Hema Bashyam, Alan Rothman
Cross-Reactive Memory Cd8(+) T Cells Alter The Immune Response To Heterologous Secondary Dengue Virus Infections In Mice In A Sequence-Specific Manner, Coreen Beaumier, Anuja Mathew, Hema Bashyam, Alan Rothman
Alan Rothman
Dengue virus is the causative agent of dengue fever and the more-severe dengue hemorrhagic fever (DHF). Human studies suggest that the increased risk of DHF during secondary infection is due to immunopathology partially mediated by cross-reactive memory T cells from the primary infection. To model T cell responses to sequential infections, we immunized mice with different sequences of dengue virus serotypes and measured the frequency of peptide-specific T cells after infection. The acute response after heterologous secondary infections was enhanced compared with the acute or memory response after primary infection. Also, the hierarchy of epitope-specific responses was influenced by the …
Immune Mediated And Inherited Defences Against Flaviviruses, Margo Brinton, Ichiro Kurane, Anuja Mathew, Lingling Zeng, Pei Shi, Alan Rothman, Francis Ennis
Immune Mediated And Inherited Defences Against Flaviviruses, Margo Brinton, Ichiro Kurane, Anuja Mathew, Lingling Zeng, Pei Shi, Alan Rothman, Francis Ennis
Alan Rothman
BACKGROUND: Flavivirus infection elicits an abundant immune response in the host which is directed against a number of the viral proteins. Resistance to flavivirus-induced disease can also be controlled via a non-immune mechanism involving the product of a naturally occurring murine gene, Flv. OBJECTIVES: To review studies that have reported the mapping of epitopes on flavivirus proteins that elicit T- or B-cell immune responses in mice or humans and to discuss a possible mechanism for flavivirus-specific genetic resistance. STUDY DESIGN: Purified viral proteins and synthetic peptides were used to map B-cell epitopes. Purified proteins, vaccinia-expressed viral protein fragments and synthetic …
Identification And Analysis For Cross-Reactivity Among Hantaviruses Of H-2b-Restricted Cytotoxic T-Lymphocyte Epitopes In Sin Nombre Virus Nucleocapsid Protein, Ken Maeda, Kim West, Tomoko Toyosaki-Maeda, Alan Rothman, Francis Ennis, Masanori Terajima
Identification And Analysis For Cross-Reactivity Among Hantaviruses Of H-2b-Restricted Cytotoxic T-Lymphocyte Epitopes In Sin Nombre Virus Nucleocapsid Protein, Ken Maeda, Kim West, Tomoko Toyosaki-Maeda, Alan Rothman, Francis Ennis, Masanori Terajima
Alan Rothman
Sin Nombre virus (SNV) causes hantavirus pulmonary syndrome (HPS), with a high rate of mortality in humans who are infected by the transmission of virus from the natural rodent host. In humans, cytotoxic T lymphocytes (CTL) specific for SNV appear to play an important role in the pathogenicity of HPS. There is a correlation between the frequencies of SNV-specific CTLs and the severity of HPS disease. In order to create a mouse model to study the role of SNV-specific T cells in vivo, T cell responses to SNV nucleocapsid (N) protein in B6.PL Thy1(a)/Cy mice (H-2(b)) immunized with plasmid DNA …
Identification Of Murine Poxvirus-Specific Cd8+ Ctl Epitopes With Distinct Functional Profiles, Anuja Mathew, Masanori Terajima, Kim West, Sharone Green, Alan Rothman, Francis Ennis, Jeffrey Kennedy
Identification Of Murine Poxvirus-Specific Cd8+ Ctl Epitopes With Distinct Functional Profiles, Anuja Mathew, Masanori Terajima, Kim West, Sharone Green, Alan Rothman, Francis Ennis, Jeffrey Kennedy
Alan Rothman
Murine T cell epitopes against vaccinia virus (VV) have not been characterized to date in part due to the large and complex genome of VV. We have identified and characterized two CD8+ T cell epitopes on the A47L (modified VV Ankara strain (MVA)-029) and J6R (MVA-043) proteins of VV that are Db and Kb restricted, respectively. Following i.p. immunization with VV New York City Board of Health (NYCBH) strain, MVA-029 peptide-stimulated splenocytes secreted IFN-gamma from 7 days to 7 mo postimmunization, and virus-stimulated effectors were also able to lyse MVA-029-pulsed target cells at the same time points. In contrast, MVA-043 …
Acute Modulation Of Sugar Transport In Brain Capillary Endothelial Cell Cultures During Activation Of The Metabolic Stress Pathway, Anthony Cura, Anthony Carruthers
Acute Modulation Of Sugar Transport In Brain Capillary Endothelial Cell Cultures During Activation Of The Metabolic Stress Pathway, Anthony Cura, Anthony Carruthers
Anthony J. Cura
GLUT1-catalyzed equilibrative sugar transport across the mammalian blood-brain barrier is stimulated during acute and chronic metabolic stress; however, the mechanism of acute transport regulation is unknown. We have examined acute sugar transport regulation in the murine brain microvasculature endothelial cell line bEnd.3. Acute cellular metabolic stress was induced by glucose depletion, by potassium cyanide, or by carbonyl cyanide p-trifluoromethoxyphenylhydrazone, which reduce or deplete intracellular ATP within 15 min. This results in a 1.7-7-fold increase in V(max) for zero-trans 3-O-methylglucose uptake (sugar uptake into sugar-free cells) and a 3-10-fold increase in V(max) for equilibrium exchange transport (intracellular [sugar] = extracellular [sugar]). …
Long Term Recall Of Memory Cd8 T Cells In Mice To First And Third Generation Smallpox Vaccines, Sharone Green, Francis Ennis, Anuja Mathew
Long Term Recall Of Memory Cd8 T Cells In Mice To First And Third Generation Smallpox Vaccines, Sharone Green, Francis Ennis, Anuja Mathew
Sharone Green
Since long-term immunity is a critical component of any effective vaccine, we compared over a 15-month period, the strength, durability and specificity of immunity of an attenuated smallpox vaccine Modified Vaccinia Ankara (MVA) to the New York City Board of Health (NYCBH) vaccine. The frequencies of CD8(+) T cells to an immunodominant CD8 T cell epitope B8R(20-27) remained remarkably stable in mice given either MVA or NYCBH. Both groups were also protected from a lethal intranasal challenge with Western Reserve strain of vaccinia virus (VACV-WR). Cytokine responses to virus-specific peptides were detectable with significant boosting upon challenge. Expression of most …
Identification Of Murine Poxvirus-Specific Cd8+ Ctl Epitopes With Distinct Functional Profiles, Anuja Mathew, Masanori Terajima, Kim West, Sharone Green, Alan Rothman, Francis Ennis, Jeffrey Kennedy
Identification Of Murine Poxvirus-Specific Cd8+ Ctl Epitopes With Distinct Functional Profiles, Anuja Mathew, Masanori Terajima, Kim West, Sharone Green, Alan Rothman, Francis Ennis, Jeffrey Kennedy
Sharone Green
Murine T cell epitopes against vaccinia virus (VV) have not been characterized to date in part due to the large and complex genome of VV. We have identified and characterized two CD8+ T cell epitopes on the A47L (modified VV Ankara strain (MVA)-029) and J6R (MVA-043) proteins of VV that are Db and Kb restricted, respectively. Following i.p. immunization with VV New York City Board of Health (NYCBH) strain, MVA-029 peptide-stimulated splenocytes secreted IFN-gamma from 7 days to 7 mo postimmunization, and virus-stimulated effectors were also able to lyse MVA-029-pulsed target cells at the same time points. In contrast, MVA-043 …
Stomatin-Like Protein 2 Deficiency In T Cells Is Associated With Altered Mitochondrial Respiration And Defective Cd4+ T Cell Responses., Darah A Christie, Panagiotis Mitsopoulos, Julianna Blagih, Stanley D Dunn, Julie St-Pierre, Russell G Jones, Grant M Hatch, Joaquín Madrenas
Stomatin-Like Protein 2 Deficiency In T Cells Is Associated With Altered Mitochondrial Respiration And Defective Cd4+ T Cell Responses., Darah A Christie, Panagiotis Mitsopoulos, Julianna Blagih, Stanley D Dunn, Julie St-Pierre, Russell G Jones, Grant M Hatch, Joaquín Madrenas
Stanley D Dunn
Stomatin-like protein 2 (SLP-2) is a mostly mitochondrial protein that regulates mitochondrial biogenesis and function and modulates T cell activation. To determine the mechanism of action of SLP-2, we generated T cell-specific SLP-2-deficient mice. These mice had normal numbers of thymocytes and T cells in the periphery. However, conventional SLP-2-deficient T cells had a posttranscriptional defect in IL-2 production in response to TCR ligation, and this translated into reduced CD4(+) T cell responses. SLP-2 deficiency was associated with impaired cardiolipin compartmentalization in mitochondrial membranes, decreased levels of the NADH dehydrogenase (ubiquinone) iron-sulfur protein 3, NADH dehydrogenase (ubiquinone) 1β subcomplex subunit …
Development And Characterization Of A Severe Acute Respiratory Syndrome-Associated Coronavirus-Neutralizing Human Monoclonal Antibody That Provides Effective Immunoprophylaxis In Mice, Thomas Greenough, Gregory Babcock, Anjeanette Roberts, Hector Hernandez, William Thomas, Jennifer Coccia, Robert Graziano, Mohan Srinivasan, Israel Lowy, Robert Finberg, Kanta Subbarao, Leatrice Vogel, Mohan Somasundaran, Katherine Luzuriaga, John Sullivan, Donna Ambrosino
Development And Characterization Of A Severe Acute Respiratory Syndrome-Associated Coronavirus-Neutralizing Human Monoclonal Antibody That Provides Effective Immunoprophylaxis In Mice, Thomas Greenough, Gregory Babcock, Anjeanette Roberts, Hector Hernandez, William Thomas, Jennifer Coccia, Robert Graziano, Mohan Srinivasan, Israel Lowy, Robert Finberg, Kanta Subbarao, Leatrice Vogel, Mohan Somasundaran, Katherine Luzuriaga, John Sullivan, Donna Ambrosino
William D Thomas Jr
BACKGROUND: Severe acute respiratory syndrome (SARS) remains a significant public health concern after the epidemic in 2003. Human monoclonal antibodies (MAbs) that neutralize SARS-associated coronavirus (SARS-CoV) could provide protection for exposed individuals. METHODS: Transgenic mice with human immunoglobulin genes were immunized with the recombinant major surface (S) glycoprotein ectodomain of SARS-CoV. Epitopes of 2 neutralizing MAbs derived from these mice were mapped and evaluated in a murine model of SARS-CoV infection. RESULTS: Both MAbs bound to S glycoprotein expressed on transfected cells but differed in their ability to block binding of S glycoprotein to Vero E6 cells. Immunoprecipitation analysis revealed …
Human Monoclonal Antibodies Directed Against Toxins A And B Prevent Clostridium Difficile-Induced Mortality In Hamsters, Gregory Babcock, Teresa Broering, Hector Hernandez, Robert Mandell, Katherine Donahue, Naomi Boatright, Anne Stack, Israel Lowy, Robert Graziano, Deborah Molrine, Donna Ambrosino, William Thomas
Human Monoclonal Antibodies Directed Against Toxins A And B Prevent Clostridium Difficile-Induced Mortality In Hamsters, Gregory Babcock, Teresa Broering, Hector Hernandez, Robert Mandell, Katherine Donahue, Naomi Boatright, Anne Stack, Israel Lowy, Robert Graziano, Deborah Molrine, Donna Ambrosino, William Thomas
William D Thomas Jr
Clostridium difficile is the leading cause of nosocomial antibiotic-associated diarrhea, and recent outbreaks of strains with increased virulence underscore the importance of identifying novel approaches to treat and prevent relapse of Clostridium difficile-associated diarrhea (CDAD). CDAD pathology is induced by two exotoxins, toxin A and toxin B, which have been shown to be cytotoxic and, in the case of toxin A, enterotoxic. In this report we describe fully human monoclonal antibodies (HuMAbs) that neutralize these toxins and prevent disease in hamsters. Transgenic mice carrying human immunoglobulin genes were used to isolate HuMAbs that neutralize the cytotoxic effects of either toxin …
Coincident Generation Of Pyramidal Neurons And Protoplasmic Astrocytes In Neocortical Columns, Sanjay Magavi, Drew Friedmann, Garrett Banks, Alberto Stolfi, Carlos Lois
Coincident Generation Of Pyramidal Neurons And Protoplasmic Astrocytes In Neocortical Columns, Sanjay Magavi, Drew Friedmann, Garrett Banks, Alberto Stolfi, Carlos Lois
Carlos Lois
Astrocytes, one of the most common cell types in the brain, are essential for processes ranging from neural development through potassium homeostasis to synaptic plasticity. Surprisingly, the developmental origins of astrocytes in the neocortex are still controversial. To investigate the patterns of astrocyte development in the neocortex we examined cortical development in a transgenic mouse in which a random, sparse subset of neural progenitors undergoes CRE/lox recombination, permanently labeling their progeny. We demonstrate that neural progenitors in neocortex generate discrete columnar structures that contain both projection neurons and protoplasmic astrocytes. Ninety-five percent of developmental cortical columns labeled in our system …
Dsarm/Sarm1 Is Required For Activation Of An Injury-Induced Axon Death Pathway, Jeannette Osterloh, Jing Yang, Timothy Rooney, A. Fox, Robert Adalbert, Eric Powell, Amy Sheehan, Michelle Avery, Rachel Hackett, Mary Logan, Jennifer Macdonald, Jennifer Ziegenfuss, Stefan Milde, Ying-Ju Hou, Carl Nathan, Aihao Ding, Robert Brown, Laura Comforti, Michael Coleman, Marc Tessier-Lavigne, Stephan Zuchner, Marc Freeman
Dsarm/Sarm1 Is Required For Activation Of An Injury-Induced Axon Death Pathway, Jeannette Osterloh, Jing Yang, Timothy Rooney, A. Fox, Robert Adalbert, Eric Powell, Amy Sheehan, Michelle Avery, Rachel Hackett, Mary Logan, Jennifer Macdonald, Jennifer Ziegenfuss, Stefan Milde, Ying-Ju Hou, Carl Nathan, Aihao Ding, Robert Brown, Laura Comforti, Michael Coleman, Marc Tessier-Lavigne, Stephan Zuchner, Marc Freeman
Dr Robert Brown
Axonal and synaptic degeneration is a hallmark of peripheral neuropathy, brain injury, and neurodegenerative disease. Axonal degeneration has been proposed to be mediated by an active autodestruction program, akin to apoptotic cell death; however, loss-of-function mutations capable of potently blocking axon self-destruction have not been described. Here, we show that loss of the Drosophila Toll receptor adaptor dSarm (sterile alpha/Armadillo/Toll-Interleukin receptor homology domain protein) cell-autonomously suppresses Wallerian degeneration for weeks after axotomy. Severed mouse Sarm1 null axons exhibit remarkable long-term survival both in vivo and in vitro, indicating that Sarm1 prodegenerative signaling is conserved in mammals. Our results provide direct …
Targeted Mutation Of Mouse Skeletal Muscle Sodium Channel Produces Myotonia And Potassium-Sensitive Weakness, Lawrence Hayward, Joanna Kim, Ming-Yang Lee, Hongru Zhou, Ji Kim, Kumudini Misra, Mohammad Salajegheh, Fen-Fen Wu, Shinji Matsuda, Valerie Reid, Didier Cros, Eric Hoffman, Jean-Marc Renaud, Stephen Cannon, Robert Brown
Targeted Mutation Of Mouse Skeletal Muscle Sodium Channel Produces Myotonia And Potassium-Sensitive Weakness, Lawrence Hayward, Joanna Kim, Ming-Yang Lee, Hongru Zhou, Ji Kim, Kumudini Misra, Mohammad Salajegheh, Fen-Fen Wu, Shinji Matsuda, Valerie Reid, Didier Cros, Eric Hoffman, Jean-Marc Renaud, Stephen Cannon, Robert Brown
Dr Robert Brown
Hyperkalemic periodic paralysis (HyperKPP) produces myotonia and attacks of muscle weakness triggered by rest after exercise or by K+ ingestion. We introduced a missense substitution corresponding to a human familial HyperKPP mutation (Met1592Val) into the mouse gene encoding the skeletal muscle voltage-gated Na+ channel NaV1.4. Mice heterozygous for this mutation exhibited prominent myotonia at rest and muscle fiber-type switching to a more oxidative phenotype compared with controls. Isolated mutant extensor digitorum longus muscles were abnormally sensitive to the Na+/K+ pump inhibitor ouabain and exhibited age-dependent changes, including delayed relaxation and altered generation of tetanic force. Moreover, rapid and sustained weakness …
Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo
Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo
Gyongyi Szabo
Infection with hepatitis C virus (HCV) is a public health problem; it establishes a chronic course in ~85% of infected patients and increases their risk for developing liver cirrhosis, hepatocellular carcinoma, and significant extrahepatic manifestations. The mechanisms of HCV persistence remain elusive and are largely related to inefficient clearance of the virus by the host immune system. Dendritic cells (DCs) are the most efficient inducers of immune responses; they are capable of triggering productive immunity and maintaining the state of tolerance to self- and non-self antigens. During the past decade, multiple research groups have focused on DCs, in hopes of …
Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo
Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo
Gyongyi Szabo
Mitochondrial dysfunction is a pathogenic feature of nonalcoholic steatohepatitis (NASH). NASH complicates hepatotropic viral disease. The mitochondrial antiviral signaling protein (MAVS) is the adapter of helicase receptors involved in sensing double-stranded RNA (dsRNA). We hypothesized that impaired MAVS function may contribute to insufficient antiviral response and liver damage in steatohepatitis. We identified reduced MAVS protein levels and increased MAVS association with the proteasome subunit alpha type 7 (PSMA7) in livers from mice given a methionine-choline-deficient (MCD) diet. Decreased association of MAVS with mitochondria and increased cytosolic cytochrome c indicated mitochondrial damage in steatohepatitis. In vivo administration of the synthetic dsRNA …