Medicine and Health Sciences Commons^™

Glutaredoxin 2 (Grx2) Knockout Increases Sensitivity To Oxidative Stress In Mouse Lens Epithelial Cells, Hongli Wu, Liren Lin, Frank Giblin, Ye-Sheh Ho, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

Glutaredoxin belongs to the oxidoreductase family with cytosolic glutaredoxin 1 (Grx1) and mitochondrial gluraredoxin 2 (Grx2) isoforms. Of the two isozymes, the function of Grx2 is not well understood. This paper studied the effect of Grx2 deletion on cellular function using primary lens epithelial cell cultures isolated from Grx2 gene knockout (KO) and wild type (WT) mice. We found that both cell types showed similar growth patterns and morphology, and comparable mitochondrial glutathione pool and complex I activity. Cells with deleted Grx2 did not show affected Grx1 or thioredoxin (Trx) expression but exhibited high sensitivity to oxidative stress. Under treatment …

Mycoplasma Haemocanis – The Canine Hemoplasma And Its Feline Counterpart In The Genomic Era, Naila C. Do Nascimento, Andrea P. Santos, Ana Ms Guimaraes, Phillip J. Sanmiguesl, Joanne Messick

Department of Comparative Pathobiology Faculty Publications

Mycoplasma haemocanis is a hemotrophic mycoplasma (hemoplasma), blood pathogen that may cause acute disease in immunosuppressed or splenectomized dogs. The genome of the strain Illinois, isolated from blood of a naturally infected dog, has been entirely sequenced and annotated to gain a better understanding of the biology of M. haemocanis. Its single circular chromosome has 919 992 bp and a low G + C content (35%), representing a typical mycoplasmal genome. A gene-by-gene comparison against its feline counterpart, M. haemofelis, reveals a very similar composition and architecture with most of the genes having conserved synteny extending over their entire chromosomes …

The Effect Of Infection Order Of Porcine Circovirus Type 2 And Porcine Reproductive And Respiratory Syndrome Virus On Dually Infected Swine Alveolar Macrophages, Yi-Chieh Tsai, Hui-Wen Chang, Chian-Ren Jeng, Tsang L. Lin, Chun-Ming Lin, Cho-Hua Wan, Victor Fei Pang

Department of Comparative Pathobiology Faculty Publications

Abstract Background: Concurrent infection with porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) is known as one of the major causes for porcine respiratory disease complex (PRDC). Dual infection with PCV2 and PRRSV is consistently to have more severe clinical presentations and pulmonary lesions than infection with PCV2 alone or PRRSV alone. However, it is not known if dual infections with PCV2 and PRRSV in different infection order may lead to different clinical symptoms in the host. To mimic the possible field conditions, swine alveolar macrophages (AMs) were inoculated with PCV2 and PRRSV in vitro …

Ultraviolet Radiation–Induced Cataract In Mice: The Effect Of Age And The Potential Biochemical Mechanism, Jie Zhang, Hong Yan, Stefan Lofgren, Xiaoli Tian, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

PURPOSE. To study the effect of age on the morphologic and biochemical alterations induced by in vivo exposure of ultraviolet radiation (UV).

METHODS. Young and old C57BL/6 mice were exposed to broadband UVBþUVA and euthanized after 2 days. Another batch of UV-exposed young mice was monitored for changes after 1, 2, 4, and 8 days. Age-matched nonexposed mice served as controls. Lens changes were documented in vivo by slit-lamp biomicroscopy and dark field microscopy photographs ex vivo. Lens homogenates were analyzed for glutathione (GSH) level, and the activities of thioredoxin (Trx), thioltransferase (TTase), and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Glutathionylated lens proteins …

Development Of Repressible Systems To Control Gene Expression In Vaccinia Virus, Allison Titong

Master's Theses

Two vaccinia virus (VACV) expression systems that contain elements from the lactose (lac) and the tetracycline (tet) operons of E. coli were developed to repress the expression of a reporter gene, enhanced green fluorescent protein (EGFP), in the presence of tet operon inducers. In the first system, lac and tet operon elements were arranged in a gene circuit, and in the presence of increasing concentrations of a lac operon inducer (isopropyl-β-D-thiogalactoside, IPTG), EGFP expression increased in a dose dependent manner and at high IPTG concentrations, expression reached the same levels as a positive control virus. Importantly, in the …

Melanopsin Mediates Retrograde Visual Signaling In The Retina, Dao-Qi Zhang, Michael A. Belenky, Patricia J. Sollars, Gary E. Pickard, Douglas G. Mcmahon

School of Veterinary and Biomedical Sciences: Faculty Publications

The canonical flow of visual signals proceeds from outer to inner retina (photoreceptors→bipolar cells→ganglion cells). However, melanopsin-expressing ganglion cells are photosensitive and functional sustained light signaling to retinal dopaminergic interneurons persists in the absence of rods and cones. Here we show that the sustained-type light response of retinal dopamine neurons requires melanopsin and that the response is mediated by AMPA-type glutamate receptors, defining a retrograde retinal visual signaling pathway that fully reverses the usual flow of light signals in retinal circuits.

Recombinant Protein Production In Bacillus Species, Isolation And Methionine Production In Methionine-Producing Microorganisms, Suwat Saengkerdsub

Graduate Theses and Dissertations

Linoleic acid isomerase (LAI) is the enzyme that converts linoleic acid to conjugated linoleic acids (CLAs) which appear to be capable of lowering cancer risk and enhancing immunity. There is an interest in developing commercial processes for the production of single isomers of CLA by biotransformation of LA using microbial cells and enzymes. However, the evaluation of these strains suggest that growth and LA isomerase production levels by these anaerobes are insufficient to support economic commercial production of single CLA isomers. A better alternative is to clone the isomerase gene and to generate new production strains using recombinant technology. Bifidobacterium …

The Presence Of Alpha Interferon At The Time Of Infection Alters The Innate And Adaptive Immune Responses To Porcine Reproductive And Respiratory Syndrome Virus, Susan L. Brockman, Crystal A. Loving, Eric A. Nelson, Laura C. Miller, Tracy L. Nicholson, Karen B. Register, Marvin J. Grubman, Douglas E. Brough, Marcus E. Kehrli Jr

Veterinary and Biomedical Sciences Faculty Publications

Porcine reproductive and respiratory syndrome (PRRS) is one of the most devastating and costly diseases to the swine industry worldwide. Overall, the adaptive immune response to PRRS virus (PRRSV) is weak, which results in delayed elimination of virus from the host and inferior vaccine protection. PRRSV has been shown to induce a meager alpha interferon (IFN-α) response, and we hypothesized that elevated IFN-α levels early in infection would shorten the induction time and increase elements of the adaptive immune response. To test this, we measured both antibody and cell-mediated immunity in pigs after the administration of a nonreplicating human adenovirus …

Development Of A Fluorescent Microsphere Immunoassay For Detection Of Antibodies Against Porcine Reproductive And Respiratory Syndrome Virus Using Oral Fluid Samples As An Alternative To Serum-Based Assays, Robert J. Langenhorst, Steven Lawson, Apisit Kittawornrat, Jeffery J. Zimmerman, Zhi Sun, Yanhua Li, Jane Christopher-Hennings, Eric A. Nelson, Ying Fang

Veterinary and Biomedical Sciences Faculty Publications

For effective disease surveillance, rapid and sensitive assays are needed to detect antibodies developed in response to porcine reproductive and respiratory syndrome virus (PRRSV) infection. In this study, we developed a multiplexed fluorescent microsphere immunoassay (FMIA) for detection of PRRSV-specific antibodies in oral fluid and serum samples. Recombinant nucleocapsid protein (N) and nonstructural protein 7 (nsp7) from both PRRSV genotypes (type I and type II) were used as antigens and covalently coupled to Luminex fluorescent microspheres. Based on an evaluation of 488 oral fluid samples with known serostatus, the oral fluid-based FMIAs achieved >92% sensitivity and 91% specificity. For serum …

Zwitterionic Chitosan Derivative, A New Biocompatible Pharmaceutical Excipient, Prevents Endotoxin-Mediated Cytokine Release, Gaurav Bajaj, William G. Van Alstine, Yoon Yeo

Department of Comparative Pathobiology Faculty Publications

Chitosan is a cationic polymer of natural origin and has been widely explored as a pharmaceutical excipient for a broad range of biomedical applications. While generally considered safe and biocompatible, chitosan has the ability to induce inflammatory reactions, which varies with the physical and chemical properties. We hypothesized that the previously reported zwitterionic chitosan (ZWC) derivative had relatively low pro-inflammatory potential because of the aqueous solubility and reduced amine content. To test this, we compared various chitosans with different aqueous solubilities or primary amine contents with respect to the intraperitoneal (IP) biocompatibility and the propensity to induce proinflammatory cytokine production …

Copper–Zinc Superoxide Dismutase-Deficient Mice Show Increased Susceptibility To Experimental Autoimmune Encephalomyelitis Induced With Myelin Oligodendrocyte Glycoprotein 35–55, Chandirasegara Massilamany, Arunakumar Gangaplara, Heejeong Kim, Charlotte Standord, Govardhan Rathnaiah, David Steffen, Jaekwon Lee, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

In this report, we have addressed the role of copper–zinc superoxide dismutase (SOD1) deficiency in the mediation of central nervous system autoimmunity. We demonstrate that SOD1-deficient C57Bl/6 mice develop more severe autoimmune encephalomyelitis induced with myelin oligodendrocyte glycoprotein (MOG) 35–55, compared with wild type mice. This alteration in the disease phenotype was not due to aberrant expansion of MOG-specific T cells nor their ability to produce inflammatory cytokines; rather lymphocytes generated in SOD1-deficient mice were more prone to spontaneous cell death when compared with their wild type littermate controls. The data point to a role for SOD1 in the maintenance …

Rhodotorula Minuta Fungemia In A Ewe Lamb, C G. Chitko-Mckown, K A. Leymaster, M. P. Heaton, D D. Griffin, J K. Veatch, S A. Jones, M. L. Clawson

School of Veterinary and Biomedical Sciences: Faculty Publications

An 8-month-old crossbred ewe, normal upon physical examination, was humanely euthanized for tissue collection. After approximately 3 weeks in tissue culture, fungi began budding out of cells obtained from the choroid plexus. After an additional 3 weeks, budding was observed in kidney cell cultures and eventually in monocyte cultures as well. Serum from the lamb was submitted to the Veterinary Diagnostic Laboratory at Colorado State University for fungal diagnosis and was found negative for Aspergillus, Blastomyces, Coccidioidomycosis and Histoplasmosis. DNA was isolated from fungi collected from tissue culture supernatants and used in a set of pan-fungal PCR assays with DNA …

Identification Of Amino Acid Residues Important For Anti-Ifn Activity Of Porcine Reproductive And Respiratory Syndrome Virus Non-Structural Protein 1, Lalit Beura, Sakthivel Subramaniam, Hiep Vu, Byungjoon Kwon, Asit K. Pattnaik, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

The non-structural protein 1 (nsp1) of porcine reproductive and respiratory syndrome virus is partly responsible for inhibition of type I interferon (IFN) response by the infected host. By performing alanine-scanning mutagenesis, we have identified amino acid residues in nsp1α and nsp1β~ (the proteolytic products of nsp1) that when substituted with alanine(s) exhibited significant relief of IFNsuppression. A mutant virus (16-SA, in which residues 16-20 of nsp1β were substituted with alanines) encoding mutant nsp1β recovered from infectious cDNA clone was shown to be attenuated for growth in vitro and induced significantly higher amount of type I IFN transcripts in infected macrophages. …

A Single Amino Acid Change Resulting In Loss Of Fluorescence Of Egfp In A Viral Fusion Protein Confers Fitness And Growth Advantage To The Recombinant Vesicular Stomatitis Virus, Phat X. Dinh, Debasis Panda, Phani B. Das, Subash C. Das, Anshuman Das, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Using a recombinant vesicular stomatitis virus encoding eGFP fused in-frame with an essential viral replication protein, the phosphoprotein P, we show that during passage in culture, the virus mutates the nucleotide C289 within eGFP of the fusion protein PeGFP to A or T, resulting in R97S/C amino acid substitution and loss of fluorescence. The resultant non-fluorescent virus exhibits increased fitness and growth advantage over its fluorescent counterpart. The growth advantage of the non-fluorescent virus appears to be due to increased transcription and replication activities of the PeGFP protein carrying the R97S/C substitution. Further, our results show that the R97S/C mutation …

Fusion Of A Fluorescent Protein To The Pul25 Minor Capsid Protein Of Pseudorabies Virus Allows Live-Cell Capsid Imaging With Negligible Impact On Infection, Kevin P. Bohannon, Patricia J. Sollars, Gary E. Pickard, Gregory A. Smith

School of Veterinary and Biomedical Sciences: Faculty Publications

In order to resolve the location and activity of submicroscopic viruses in living cells, viral proteins are often fused to fluorescent proteins (FPs) and visualized by microscopy. In this study, we describe the fusion of FPs to three proteins of pseudorabies virus (PRV) that allowed imaging of capsids in living cells. Included in this study are the first recombinant PRV strains expressing FP–pUL25 fusions based on a design applied to herpes simplex virus type 1 by Homa and colleagues. The properties of each reporter virus were compared in both in vitro and in vivo infection models. PRV strains expressing FP–pUL25 …

Posttranslational Modification Of Vesicular Stomatitis Virus Glycoprotein, But Not Jnk Inhibition, Is The Antiviral Mechanism Of Sp600125, Sabrina Marozin, Jennifer Altomonte, Sibylle Apfel, Phat X. Dinh, Enrico De Toni, Antonia Rizzani, Andreas Nüssler, Nobuyuki Kato, Roland M. Schmid, Asit K. Pattnaik, Oliver Eberta

School of Veterinary and Biomedical Sciences: Faculty Publications

Vesicular stomatitis virus (VSV), a negative-sense single-stranded-RNA rhabdovirus, is an extremely promising oncolytic agent for cancer treatment. Since oncolytic virotherapy is moving closer to clinical application, potentially synergistic combinations of oncolytic viruses and molecularly targeted antitumor agents are becoming a meaningful strategy for cancer treatment. Mitogenactivated protein kinase (MAPK) inhibitors have been shown to impair liver cell proliferation and tumor development, suggesting their potential use as therapeutic agents for hepatocellular carcinoma (HCC). In this work, we show that the impairment of MAPK in vitro did not interfere with the oncolytic properties of VSV in HCC cell lines. Moreover, the administration …

Glycosyl-Phosphatidylinositol (Gpi)-Anchored Membrane Association Of The Porcine Reproductive And Respiratory Syndrome Virus Gp4 Glycoprotein And Its Co-Localization With Cd163 In Lipid Rafts, Yijun Du, Asit K. Pattnaik, Cheng Song, Dongwan Yoo, Gang Li

School of Veterinary and Biomedical Sciences: Faculty Publications

The porcine reproductive and respiratory syndrome virus (PRRSV) glycoprotein 4 (GP4) resembles a typical type I membrane protein in its structure but lacks a hydrophilic tail at the C-terminus, suggesting that GP4 may be a lipid-anchored membrane protein. Using the human decay-accelerating factor (DAF; CD55), a known glycosyl-phosphatidylinositol (GPI) lipid-anchored protein, chimeric constructs were made to substitute the GPI-anchor domain of DAF with the putative lipid-anchor domain of GP4, and their membrane association and lipase cleavage were determined in cells. The DAF-GP4 fusion protein was transported to the plasma membrane and was cleaved by phosphatidylinositol-specific phospholipase C (PI-PLC), indicating that …

Staphylococcal Response To Oxidative Stress, Rosmarie Gaupp, Nagender Ledala, Greg A. Somerville

School of Veterinary and Biomedical Sciences: Faculty Publications

Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous osidative and nitrosative stress are often due to the bacteria's interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, …

Development And Characterization Of A Murine Model Of Rickettsia Parkeri Rickettsiosis, Britton Grasperge

LSU Doctoral Dissertations

Rickettsia parkeri, a member of the spotted fever group of Rickettsia, is the agent of an emerging rickettsiosis in the southeastern United States and South America. Despite increased recognition of human cases, limited information is available regarding infection of invertebrate and vertebrate hosts for this emerging tick-borne disease. Towards development of a viable transmission model and to further characterize the pathology associated with R. parkeri infection, inbred mouse strains (A/J, Balb/C, C3H/HeJ, and C3H/HeN) were intravenously and intradermally inoculated with R. parkeri. The C3H/HeJ strain of mice were identified as the most susceptible to R. parkeri infection and were found …

Amino Acid Residues In The Non-Structural Protein 1 Of Porcine Reproductive And Respiratory Syndrome Virus Involved In Down-Regulation Of Tnf-Cx Expression In Vitro And Attenuation In Vivo, Sakthivel Subramaniam, Lalit Beura, Byungjoon Kwon, Asit K. Pattnaik, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine reproductive and respiratory syndrome virus (PRRSV) suppresses tumor necrosis factor-alpha (TNF-α) production at both transcriptional and post-transcriptional levels by its non-structural proteins 1α and 1β (Nsp1α and Nsp1β). To identifY the amino acid residues responsible for this activity, we generated several alanine substitution mutants of Nsp1α and Nsp1β. Examination of the mutant proteins revealed that Nsp1α residues Gly90, Asn91 , Arg97, Argl 00 and Arg124 were necessary for TNF-α promoter suppression, whereas several amino acids spanning the entire Nsp1β ~ were found to be required for this activity. Two mutant viruses, with mutations at Nsp1α Gly90 or Nsp1β residues …

The Role Of Gylcoprotein K (Gk) In The Ocular And Neuropathogenesis Of Herpes Simplex Virus-Type 1 (Hsv-1), Andrew Timothy David

LSU Doctoral Dissertations

Herpes simplex virus type 1 (HSV-1) is a DNA virus that is a ubiquitous pathogen of humans. The hallmark of the HSV-lifecycle is infection of a mucosal surface with spread to sensory neurons where the virus establishes a latent infection with periodic recurrences for the life of the host. The most common course of symptomatic disease with HSV-1 is the typical mucocutaneous lesion that is self-limiting. HSV-1 can also cause acute encephalitis and ocular pathology on reactivation. Both of these manifestations of the disease have severe consequences. Although ocular infection is less frequent, the extensive prevalence of HSV makes it …

Role Of Herpes Simplex Type I Glycoproteins In Entry And Cell-Cell Fusion, Sona Chowdhury

LSU Doctoral Dissertations

Herpes simplex virus type I (HSV-1) is a neurotropic virus that infects primarily mucocutaneous epithelial cells and nervous tissue. Membrane fusion is an important aspect of the HSV-1 lifecycle, that occurs during viral entry (virus-cell fusion), viral spread (cell-to-cell fusion), as well as, during virion morphogenesis (assembly and egress). These membrane fusion steps involve complex interactions between multiple viral glycoproteins and cellular receptors. HSV-1 glycoprotein B (gB) is necessary but not sufficient for membrane fusion events. Despite the fact, that the majority of known hypermorphic mutations which cause extensive virus-induced cell fusion occur within glycoprotein K (gK); yet the role …

Essential Role Of Monocyte Chemoattractant Protein-1 In Gram-Negative Bacterial Pneumonia, Gayathriy Balamayooran

LSU Doctoral Dissertations

Acute gram-negative bacterial infections are a leading cause of mortality among the nosocomial infections. Increasing numbers of immunosuppressed individuals and growing numbers of antibiotic resistant strains make antibiotic treatment difficult. Neutrophils are the first cells recruited to the site of infection and are critical players in the host defense against gram-negative bacterial pneumonia. Therefore, identification of targets that boost neutrophil-associated host defense in the lung is essential in designing better therapies to control pulmonary infections. Production of chemokines is an important step for neutrophil recruitment. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that is important for monocyte and T-lymphocyte influx. …

Koutango: Under Reported Arboviral Disease In West Africa, Jaime Matias De Araujo Lobo

LSU Doctoral Dissertations

Arthropod-borne viruses (arboviruses) are among the most common agents of human febrile illnesses worldwide. As crucially important emerging pathogens, they have caused multiple, notable epidemics of human disease and unnoticed epizootics over recent decades. Despite the public health relevance, very little is known about the geographic distribution of the agents and vectors, relative impact, and risk factors associated to the arboviral infection in many regions of the world and in the tropics in particular. Presented in this dissertation is an experimental study that explores the serology screening of serum samples from 151 patients whom were diagnosed with undifferentiated febrile illness …

Immunization Of West Nile Recombinant Envelope Domain Iii With Equine Cd40 Ligand Protein Vaccine Induced Specific Immune Response In Rabbits And Horses, Shiliang Anthony Liu

LSU Master's Theses

West Nile virus (WNV) is one of several flaviruses known to infect mammalian species, including humans. There were 15,257 horse cases reported in 2002 and 1,086 in 2006 in United States. Recently, significant increases in equine and human cases have been reported in United States. Domain III of the WNV envelope protein binds to cellular receptors, and induces a significant portion of the neutralizing antibody response against the virus. CD40 Ligand (CD40L, CD154) enhances productive interactions between T cells and APC and has been shown to function as a potential adjuvant. In this study, we constructed and expressed a fusion …