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Influence Of Env And Long Terminal Repeat Sequences On The Tissue Tropism Of Avian Leukosis Viruses, David Brown, Harriet Robinson Dec 2015

Influence Of Env And Long Terminal Repeat Sequences On The Tissue Tropism Of Avian Leukosis Viruses, David Brown, Harriet Robinson

David C. Brown

Adsorption and penetration of retroviruses into eucaryotic cells is mediated by retroviral envelope glycoproteins interacting with host receptors. Recombinant avian leukosis viruses (ALVs) differing only in envelope determinants that interact with host receptors for subgroup A or E ALVs have been found to have unexpectedly distinctive patterns of tissue-specific replication. Recombinants of both subgroups were highly expressed in bursal lymphocytes as well as in cultured chicken embryo fibroblasts. In contrast, the subgroup A but not subgroup E host range allowed high levels of expression in skeletal muscle, while subgroup E but not subgroup A envelope glycoproteins permitted efficient replication in …


Differential Effects Of Egf And Tgf-Beta1 On Fibroblast Activity In Fibrin-Based Tissue Equivalents, Jaime Grouf, Angela Throm, Jenna Balestrini, Katie Bush, Kristen Billiar Dec 2015

Differential Effects Of Egf And Tgf-Beta1 On Fibroblast Activity In Fibrin-Based Tissue Equivalents, Jaime Grouf, Angela Throm, Jenna Balestrini, Katie Bush, Kristen Billiar

Kristen L. Billiar

Transforming growth factor-beta1 (TGF-beta1) is commonly used to promote matrix production for engineered tissues in vitro, yet it also enhances fibroblast contractility. For applications where contraction is undesirable, we hypothesized that epidermal growth factor (EGF) would yield equivalent mechanical properties without enhancing contractility. In this study, the response of human dermal fibroblasts to EGF (5 ng/mL) and TGF-beta1 (5 ng/mL) was determined within hemispheric fibrin-based gels by assessing matrix compaction and strength, cell number, collagen production, and contractility. After 3 weeks, both cytokines enhanced compaction relative to controls, and EGF roughly doubled matrix strength over controls and TGF-beta1-treated samples. TGF-beta1 …


Argonaute Protein Identity And Pairing Geometry Determine Cooperativity In Mammalian Rna Silencing, Jennifer Broderick, William Salomon, Sean Ryder, Neil Aronin, Phillip Zamore May 2015

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 …


Fbf Represses The Cip/Kip Cell-Cycle Inhibitor Cki-2 To Promote Self-Renewal Of Germline Stem Cells In C. Elegans, Irene Kalchhauser, Brian Farley, Sandra Pauli, Sean Ryder, Rafal Ciosk May 2015

Fbf Represses The Cip/Kip Cell-Cycle Inhibitor Cki-2 To Promote Self-Renewal Of Germline Stem Cells In C. Elegans, Irene Kalchhauser, Brian Farley, Sandra Pauli, Sean Ryder, Rafal Ciosk

Sean P. Ryder

Although the decision between stem cell self-renewal and differentiation has been linked to cell-cycle modifications, our understanding of cell-cycle regulation in stem cells is very limited. Here, we report that FBF/Pumilio, a conserved RNA-binding protein, promotes self-renewal of germline stem cells by repressing CKI-2(Cip/Kip), a Cyclin E/Cdk2 inhibitor. We have previously shown that repression of CYE-1 (Cyclin E) by another RNA-binding protein, GLD-1/Quaking, promotes germ cell differentiation. Together, these findings suggest that a post-transcriptional regulatory circuit involving FBF and GLD-1 controls the self-renewal versus differentiation decision in the germline by promoting high CYE-1/CDK-2 activity in stem cells, and inhibiting CYE-1/CDK-2 …


Human Type 2 Myeloid Dendritic Cells Produce Interferon-Lambda And Amplify Interferon-Alpha In Response To Hepatitis C Virus Infection, Shuye Zhang, Karen Kodys, Kui Li, Gyongyi Szabo Sep 2014

Human Type 2 Myeloid Dendritic Cells Produce Interferon-Lambda And Amplify Interferon-Alpha In Response To Hepatitis C Virus Infection, Shuye Zhang, Karen Kodys, Kui Li, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND and AIMS: The type III interferons (IFN-lambdas: interleukin [IL]-28a, IL-28b, and IL-29) have important roles in hepatitis C virus (HCV) infection, but little is understood about what cells produce these cytokines or how production is activated. We investigated whether human immune cells recognize HCV-infected cells and respond by producing IFN-lambda. METHODS: We cultured healthy human peripheral blood mononuclear cells (PBMCs) with different populations of immune cells and Japanese fulminant hepatitis-1 (JFH-1) HCV-infected Huh7.5 (cell culture-derived HCV particles [HCVcc]/Huh7.5) cells. RESULTS: Human PBMCs recognized HCVcc/Huh7.5 cells and responded by producing IFN-alpha, IFN-gamma, and IFN-lambda. A rare subset of myeloid dendritic …


Pubertal And Adult Leydig Cell Function In Mullerian Inhibiting Substance-Deficient Mice, Xiufeng Wu, Ramamani Arumugam, Stephen Baker, Mary Lee Sep 2014

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 …


Mullerian-Inhibiting Substance Type Ii Receptor Expression And Function In Purified Rat Leydig Cells, Mary Lee, C. Seah, P. Masiakos, Chantal Sottas, F. Preffer, Patricia Donahoe, David Maclaughlin, Matthew Hardy Sep 2014

Mullerian-Inhibiting Substance Type Ii Receptor Expression And Function In Purified Rat Leydig Cells, Mary Lee, C. Seah, P. Masiakos, Chantal Sottas, F. Preffer, Patricia Donahoe, David Maclaughlin, Matthew Hardy

Mary M. Lee

Mullerian-inhibiting substance (MIS), a gonadal hormone in the transforming growth factor-beta superfamily, induces Mullerian duct involution during male sexual differentiation. Mice with null mutations of the MIS ligand or receptor develop Leydig cell hyperplasia and neoplasia in addition to retained Mullerian ducts, whereas MIS-overexpressing transgenic mice have decreased testosterone concentrations and Leydig cell numbers. We hypothesized that MIS directly modulates Leydig cell proliferation and differentiated function in the maturing testis. Therefore, highly purified rat Leydig and Sertoli cells were isolated to examine cell-specific expression, binding, and function of the MIS type II receptor. These studies revealed that this receptor is …


Virus-Induced Decline In Soluble Vascular Endothelial Growth Receptor 2 Is Associated With Plasma Leakage In Dengue Hemorrhagic Fever, Anon Srikiatkhachorn, Chuanpis Ajariyakhajorn, Timothy Endy, Siripen Kalayanarooj, Daniel Libraty, Sharone Green, Francis Ennis, Alan Rothman Aug 2014

Virus-Induced Decline In Soluble Vascular Endothelial Growth Receptor 2 Is Associated With Plasma Leakage In Dengue Hemorrhagic Fever, Anon Srikiatkhachorn, Chuanpis Ajariyakhajorn, Timothy Endy, Siripen Kalayanarooj, Daniel Libraty, Sharone Green, Francis Ennis, Alan Rothman

Alan Rothman

Some individuals infected with dengue virus develop dengue hemorrhagic fever (DHF), a viral hemorrhagic disease characterized by a transient period of localized plasma leakage. To determine the importance of vascular endothelial growth factor A (VEGF-A) in this syndrome, we compared plasma levels of VEGF-A and the soluble forms of its receptors in patients with DHF to patients with dengue fever (DF), a milder form of dengue virus infection without plasma leakage. We observed a rise in the plasma levels of free, but not total VEGF-A in DHF patients at the time of plasma leakage. This was associated with a decline …


Efficient Dengue Virus (Denv) Infection Of Human Muscle Satellite Cells Upregulates Type I Interferon Response Genes And Differentially Modulates Mhc I Expression On Bystander And Denv-Infected Cells, Rajas Warke, Aniuska Becerra, Agatha Zawadzka, Diane Schmidt, Katherine Martin, Krisanthi Giaya, Jonathan Dinsmore, Marcia Woda, Gregory Hendricks, Tracy Levine, Alan Rothman, Irene Bosch Aug 2014

Efficient Dengue Virus (Denv) Infection Of Human Muscle Satellite Cells Upregulates Type I Interferon Response Genes And Differentially Modulates Mhc I Expression On Bystander And Denv-Infected Cells, Rajas Warke, Aniuska Becerra, Agatha Zawadzka, Diane Schmidt, Katherine Martin, Krisanthi Giaya, Jonathan Dinsmore, Marcia Woda, Gregory Hendricks, Tracy Levine, Alan Rothman, Irene Bosch

Alan Rothman

Dengue virus (DENV) is a mosquito-borne flavivirus that causes an acute febrile disease in humans, characterized by musculoskeletal pain, headache, rash and leukopenia. The cause of myalgia during DENV infection is still unknown. To determine whether DENV can infect primary muscle cells, human muscle satellite cells were exposed to DENV in vitro. The results demonstrated for the first time high-efficiency infection and replication of DENV in human primary muscle satellite cells. Changes in global gene expression were also examined in these cells following DENV infection using Affymetrix GeneChip analysis. The differentially regulated genes belonged to two main functional categories: cell …


Dengue Virus Induces Novel Changes In Gene Expression Of Human Umbilical Vein Endothelial Cells, Rajas Warke, Kris Xhaja, Katherine Martin, Marcia Fournier, Sunil Shaw, Nathaly Brizuela, Norma De Bosch, David Lapointe, Francis Ennis, Alan Rothman, Irene Bosch Aug 2014

Dengue Virus Induces Novel Changes In Gene Expression Of Human Umbilical Vein Endothelial Cells, Rajas Warke, Kris Xhaja, Katherine Martin, Marcia Fournier, Sunil Shaw, Nathaly Brizuela, Norma De Bosch, David Lapointe, Francis Ennis, Alan Rothman, Irene Bosch

Alan Rothman

Endothelial cells are permissive to dengue virus (DV) infection in vitro, although their importance as targets of DV infection in vivo remains a subject of debate. To analyze the virus-host interaction, we studied the effect of DV infection on gene expression in human umbilical vein endothelial cells (HUVECs) by using differential display reverse transcription-PCR (DD-RTPCR), quantitative RT-PCR, and Affymetrix oligonucleotide microarrays. DD identified eight differentially expressed cDNAs, including inhibitor of apoptosis-1, 2'-5' oligoadenylate synthetase (OAS), a 2'-5' OAS-like (OASL) gene, galectin-9, myxovirus protein A (MxA), regulator of G-protein signaling, endothelial and smooth muscle cell-derived neuropilin-like protein, and phospholipid scramblase 1. …


Predominance Of Hla-Restricted Cytotoxic T-Lymphocyte Responses To Serotype-Cross-Reactive Epitopes On Nonstructural Proteins Following Natural Secondary Dengue Virus Infection, Anuja Mathew, Ichiro Kurane, Sharone Green, Henry Stephens, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Dasnayanee Chandanayingyong, Francis Ennis, Alan Rothman Aug 2014

Predominance Of Hla-Restricted Cytotoxic T-Lymphocyte Responses To Serotype-Cross-Reactive Epitopes On Nonstructural Proteins Following Natural Secondary Dengue Virus Infection, Anuja Mathew, Ichiro Kurane, Sharone Green, Henry Stephens, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Dasnayanee Chandanayingyong, Francis Ennis, Alan Rothman

Alan Rothman

We examined the memory cytotoxic T-lymphocytic (CTL) responses of peripheral blood mononuclear cells (PBMC) obtained from patients in Thailand 12 months after natural symptomatic secondary dengue virus infection. In all four patients analyzed, CTLs were detected in bulk culture PBMC against nonstructural dengue virus proteins. Numerous CD4+ and CD8+ CTL lines were generated from the bulk cultures of two patients, KPP94-037 and KPP94-024, which were specific for NS1.2a (NS1 and NS2a collectively) and NS3 proteins, respectively. All CTL lines derived from both patients were cross-reactive with other serotypes of dengue virus. The CD8+ NS1.2a-specific lines from patient KPP94-037 were HLA …


Dominant Recognition By Human Cd8+ Cytotoxic T Lymphocytes Of Dengue Virus Nonstructural Proteins Ns3 And Ns1.2a, Anuja Mathew, Ichiro Kurane, Alan Rothman, Lingling Zeng, Margo Brinton, Francis Ennis Aug 2014

Dominant Recognition By Human Cd8+ Cytotoxic T Lymphocytes Of Dengue Virus Nonstructural Proteins Ns3 And Ns1.2a, Anuja Mathew, Ichiro Kurane, Alan Rothman, Lingling Zeng, Margo Brinton, Francis Ennis

Alan Rothman

A severe complication of dengue virus infection, dengue hemorrhagic fever (DHF), is hypothesized to be immunologically mediated and virus-specific cytotoxic T lymphocytes (CTLs) may trigger DHF. It is also likely that dengue virus-specific CTLs are important for recovery from dengue virus infections. There is little available information on the human CD8+ T cell responses to dengue viruses. Memory CD8+CTL responses were analyzed to determine the diversity of the T cell response to dengue virus and to identify immunodominant proteins using PBMC from eight healthy adult volunteers who had received monovalent, live-attenuated candidate vaccines of the four dengue serotypes. All the …


Dengue Virus-Reactive Cd8+ T Cells Display Quantitative And Qualitative Differences In Their Response To Variant Epitopes Of Heterologous Viral Serotypes, Hema Bashyam, Sharone Green, Alan Rothman Aug 2014

Dengue Virus-Reactive Cd8+ T Cells Display Quantitative And Qualitative Differences In Their Response To Variant Epitopes Of Heterologous Viral Serotypes, Hema Bashyam, Sharone Green, Alan Rothman

Alan Rothman

Reactivation of serotype cross-reactive CD8+ memory T lymphocytes is thought to contribute to the immunopathogenesis of dengue disease during secondary infection by a heterologous serotype. Using cytokine flow cytometry, we have defined four novel HLA-A*02-restricted dengue viral epitopes recognized by up to 1.5% of circulating CD8+ T cells in four donors after primary vaccination. All four donors had the highest cytokine response to the epitope NS4b 2353. We also studied the effect of sequence differences in heterologous dengue serotypes on dengue-reactive CD8+ memory T cell cytokine and proliferative responses. The D3 variant of a different NS4b epitope 2423 and the …


Trail Is A Novel Antiviral Protein Against Dengue Virus, Rajas Warke, Katherine Martin, Krisanthi Giaya, Sunil Shaw, Alan Rothman, Irene Bosch Aug 2014

Trail Is A Novel Antiviral Protein Against Dengue Virus, Rajas Warke, Katherine Martin, Krisanthi Giaya, Sunil Shaw, Alan Rothman, Irene Bosch

Alan Rothman

Dengue fever is an important tropical illness for which there is currently no virus-specific treatment. To shed light on mechanisms involved in the cellular response to dengue virus (DV), we assessed gene expression changes, using Affymetrix GeneChips (HG-U133A), of infected primary human cells and identified changes common to all cells. The common response genes included a set of 23 genes significantly induced upon DV infection of human umbilical vein endothelial cells (HUVECs), dendritic cells (DCs), monocytes, and B cells (analysis of variance, P < 0.05). Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), one of the common response genes, was identified as a …


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 Aug 2014

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 …


Predominance Of Hla-Restricted Cytotoxic T-Lymphocyte Responses To Serotype-Cross-Reactive Epitopes On Nonstructural Proteins Following Natural Secondary Dengue Virus Infection, Anuja Mathew, Ichiro Kurane, Sharone Green, Henry Stephens, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Dasnayanee Chandanayingyong, Francis Ennis, Alan Rothman Jan 2014

Predominance Of Hla-Restricted Cytotoxic T-Lymphocyte Responses To Serotype-Cross-Reactive Epitopes On Nonstructural Proteins Following Natural Secondary Dengue Virus Infection, Anuja Mathew, Ichiro Kurane, Sharone Green, Henry Stephens, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Dasnayanee Chandanayingyong, Francis Ennis, Alan Rothman

Sharone Green

We examined the memory cytotoxic T-lymphocytic (CTL) responses of peripheral blood mononuclear cells (PBMC) obtained from patients in Thailand 12 months after natural symptomatic secondary dengue virus infection. In all four patients analyzed, CTLs were detected in bulk culture PBMC against nonstructural dengue virus proteins. Numerous CD4+ and CD8+ CTL lines were generated from the bulk cultures of two patients, KPP94-037 and KPP94-024, which were specific for NS1.2a (NS1 and NS2a collectively) and NS3 proteins, respectively. All CTL lines derived from both patients were cross-reactive with other serotypes of dengue virus. The CD8+ NS1.2a-specific lines from patient KPP94-037 were HLA …


Dengue Virus-Reactive Cd8+ T Cells Display Quantitative And Qualitative Differences In Their Response To Variant Epitopes Of Heterologous Viral Serotypes, Hema Bashyam, Sharone Green, Alan Rothman Jan 2014

Dengue Virus-Reactive Cd8+ T Cells Display Quantitative And Qualitative Differences In Their Response To Variant Epitopes Of Heterologous Viral Serotypes, Hema Bashyam, Sharone Green, Alan Rothman

Sharone Green

Reactivation of serotype cross-reactive CD8+ memory T lymphocytes is thought to contribute to the immunopathogenesis of dengue disease during secondary infection by a heterologous serotype. Using cytokine flow cytometry, we have defined four novel HLA-A*02-restricted dengue viral epitopes recognized by up to 1.5% of circulating CD8+ T cells in four donors after primary vaccination. All four donors had the highest cytokine response to the epitope NS4b 2353. We also studied the effect of sequence differences in heterologous dengue serotypes on dengue-reactive CD8+ memory T cell cytokine and proliferative responses. The D3 variant of a different NS4b epitope 2423 and the …


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 Jan 2014

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 …


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 Aug 2013

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 …


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 Dec 2012

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 …


Novel Developmental Biology-Based Protocol Of Embryonic Stem Cell Differentiation To Morphologically Sound And Functional Yet Immature Hepatocytes, Terence Bukong, Tracie Lo, Gyongyi Szabo, Angela Dolganiuc Oct 2012

Novel Developmental Biology-Based Protocol Of Embryonic Stem Cell Differentiation To Morphologically Sound And Functional Yet Immature Hepatocytes, Terence Bukong, Tracie Lo, Gyongyi Szabo, Angela Dolganiuc

Gyongyi Szabo

BACKGROUND/AIMS: Liver diseases are common in the United States and often require liver transplantation; however, donated organs are limited and thus alternative sources for liver cells are in high demand. Embryonic stem cells (ESC) can provide a continuous and readily available source of liver cells. ESC differentiation to liver cells is yet to be fully understood and comprehensive differentiation protocols are yet to be defined. Here, we aimed to achieve human (h)ESC differentiation into mature hepatocytes using defined recombinant differentiation factors and metabolites. METHODS: Embryonic stem cell H1 line was sub-cultured on feeder layer. We induced hESCs into endodermal differentiation …


Effect Of Ethanol On Inflammatory Responses. Implications For Pancreatitis, Gyongyi Szabo, Pranoti Mandrekar, Shilpa Oak, Julia Mayerle Apr 2010

Effect Of Ethanol On Inflammatory Responses. Implications For Pancreatitis, Gyongyi Szabo, Pranoti Mandrekar, Shilpa Oak, Julia Mayerle

Gyongyi Szabo

BACKGROUND/AIMS: Alcohol use alters inflammatory cell responses. While alcohol has direct effects on pancreatic acinar cells, activation of inflammatory cells is a major component of the pathology of alcoholic pancreatitis.

METHODS: The effects of acute or chronic alcohol exposure were evaluated in human monocytes on the production of TNFalpha or IL-10 production, pro-inflammatory gene and nuclear factor-kappaB (NF-kappaB) activation.

RESULTS: Moderate, acute alcohol consumption or equivalent doses of alcohol in vitro had anti-inflammatory effects on monocyte activation via inhibition of pro-inflammatory genes and NF-kappaB activation, inhibition of TNFalpha production and augmentation of the anti-inflammatory cytokine, IL-10. In contrast, acute alcohol …


Acute Ethanol Treatment Augments Interleukin-12 Production In Activated Human Monocytes, Gyongyi Szabo, Linda Girouard, Pranoti Mandrekar, Donna Catalano Apr 2010

Acute Ethanol Treatment Augments Interleukin-12 Production In Activated Human Monocytes, Gyongyi Szabo, Linda Girouard, Pranoti Mandrekar, Donna Catalano

Gyongyi Szabo

No abstract provided.


Human Monocytes, Macrophages, And Dendritic Cells: Alcohol Treatment Methods, Gyongyi Szabo, Pranoti Mandrekar Apr 2010

Human Monocytes, Macrophages, And Dendritic Cells: Alcohol Treatment Methods, Gyongyi Szabo, Pranoti Mandrekar

Gyongyi Szabo

Both acute and chronic alcohol consumption have significant immunomodulatory effects of which alterations in innate immune functions contribute to impaired antimicrobial defense and inflammatory responses. Blood monocytes, macrophages, and dendritic cells play a central role in innate immune recognition as these cells recognize pathogens, respond with inflammatory cytokine production, and induce antigen-specific T-lymphocyte activation. All of these innate immune cell functions are affected in humans by alcohol intake. Here, we summarize the different effects of acute and chronic alcohol on monocyte, macrophage, and dendritic cell functions in humans and describe methods for separation and functional evaluation of these cell types.


Human Macrophages Degrade Tryptophan Upon Induction By Interferon-Gamma, Ernst Werner, Gabriele Bitterlich, Dietmar Fuchs, Arno Hausen, Gilbert Reibnegger, Gyongyi Szabo, Manfred Dierich, Helmut Wachter Apr 2010

Human Macrophages Degrade Tryptophan Upon Induction By Interferon-Gamma, Ernst Werner, Gabriele Bitterlich, Dietmar Fuchs, Arno Hausen, Gilbert Reibnegger, Gyongyi Szabo, Manfred Dierich, Helmut Wachter

Gyongyi Szabo

Human peripheral blood mononuclear cells, monocytes-macrophages and T-cells were stimulated with human recombinant interferon-gamma, interferon-alpha and phytohemagglutinin. The culture supernatants were analyzed for tryptophan, kynurenine, 3-hydroxyanthranilic acid, anthranilic acid and neopterin by high performance liquid chromatography. Tryptophan was decreased and the four other compounds were increased in supernatants of peripheral blood mononuclear cells activated by interferon-gamma (250 U/ml), interferon-alpha (10.000 U/ml) and phytohemagglutinin (1 microgram/ml). After splitting of peripheral blood mononuclear cells by adherence, the monocytes and macrophages but not the T-cells degraded tryptophan upon stimulation by interferon-gamma in a dose dependent manner. Supernatants of phytohemagglutinin stimulated but not of …


Subversion Of Plasmacytoid And Myeloid Dendritic Cell Functions In Chronic Hcv Infection, Gyongyi Szabo, Angela Dolganiuc Apr 2010

Subversion Of Plasmacytoid And Myeloid Dendritic Cell Functions In Chronic Hcv Infection, Gyongyi Szabo, Angela Dolganiuc

Gyongyi Szabo

Insufficient elimination of the hepatitis C virus (HCV) during acute infection results in chronic disease in the majority of patients due to weak virus-specific immune responses. Dendritic cells (DC) play a central role in recognition of HCV and in induction of innate and adaptive immune responses. In this study, we evaluated the frequency and functions of plasmacytoid dendritic cells (PDC) and myeloid dendritic cells (MDC) in patients with chronic HCV infection. We found that both the numbers and IFNalpha production capacity of blood PDC were significantly reduced in patients with chronic HCV infection compared to normal controls. While the frequency …


Inhibition Of Antigen-Presenting Cell Functions By Alcohol: Implications For Hepatitis C Virus Infection, Gyongyi Szabo, Angela Dolganiuc, Pranoti Mandrekar, Bernadette White Apr 2010

Inhibition Of Antigen-Presenting Cell Functions By Alcohol: Implications For Hepatitis C Virus Infection, Gyongyi Szabo, Angela Dolganiuc, Pranoti Mandrekar, Bernadette White

Gyongyi Szabo

The mechanisms of alcohol-induced immunosuppression include defects in innate and adaptive immune responses. Monocytes and dendritic cells (DCs) link innate and adaptive immune responses as they recognize viral antigens and induce antigen-specific T-cell activation. We investigated the effects of alcohol on antigen-presenting cell functions. Acute alcohol consumption by healthy volunteers (vodka, 2 ml/kg) resulted in significantly reduced antigen-presenting cell function of monocyte-derived DCs. Reduced allostimulatory capacity of DCs treated with alcohol in vitro correlated with decreased co-stimulatory molecule (B7.1 and B7.2) expression, as well as with reduced interleukin (IL)-12 and increased IL-10 concentrations, in mixed lymphocyte cultures. Dendritic cells recognize …


Heme Oxygenase-1 Mediates The Anti-Inflammatory Effects Of Acute Alcohol On Il-10 Induction Involving P38 Mapk Activation In Monocytes, Yvonne Drechsler, Angela Dolganiuc, Oxana Norkina, Laszlo Romics, Weibo Li, Karen Kodys, Fritz Bach, Pranoti Mandrekar, Gyongyi Szabo Apr 2010

Heme Oxygenase-1 Mediates The Anti-Inflammatory Effects Of Acute Alcohol On Il-10 Induction Involving P38 Mapk Activation In Monocytes, Yvonne Drechsler, Angela Dolganiuc, Oxana Norkina, Laszlo Romics, Weibo Li, Karen Kodys, Fritz Bach, Pranoti Mandrekar, Gyongyi Szabo

Gyongyi Szabo

Inflammation and immunoregulatory cytokines play a central role in alcohol-induced liver damage. We previously reported that acute alcohol treatment augments IL-10 and inhibits TNF-alpha production in monocytes. Heme oxygenase-1 (HO-1), a stress-inducible protein, also regulates IL-10 and TNF-alpha production. Here, we report that augmentation of LPS-induced IL-10 production by alcohol was prevented by inhibition of HO-1 activity. Acute ethanol increased LPS-induced enzyme activity and RNA levels of HO-1, and DNA binding of AP-1, a transcription factor essential in HO-1 regulation. LPS-induced phospho-p38 MAPK levels were augmented by ethanol treatment and the p38 inhibitor, SB203580, prevented both the ethanol-induced increase in …