Veterinary Pathology and Pathobiology Commons^™

Development And Evaluation Of A Replicon Particle Vaccine Expressing The E2 Glycoprotein Of Bovine Viral Diarrhea Virus (Bvdv) In Cattle, John Dustin Loy, Jill Gander, Mark Mogler, Ryan Vander Veen, Julia Ridpath, Delbert Hank Harris, Kurt Kamrud

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Bovine viral diarrhea virus is one of the most significant and costly viral pathogens of cattle worldwide. Alphavirus-derived replicon particles have been shown to be safe and highly effective vaccine vectors against a variety of human and veterinary pathogens. Replicon particles are non-propagating, DIVA compatible, and can induce both humoral and cell mediated immune responses. This is the first experiment to demonstrate that Alphavirus-based replicon particles can be utilized in a standard prime/boost vaccination strategy in calves against a commercially significant bovine pathogen.

Findings: Replicon particles that express bovine viral diarrhea virus sub-genotype 1b E2 glycoprotein were …

A Dysfunctional Tricarboxylic Acid Cycle Enhances Fitness Of Staphylococcus Epidermidis During Β-Lactam Stress, Vinai Chittenzham Thomas, Lauren Kinkhead, Ashley Janssen, Carolyn Schaeffer, Keith Woods, Jill Lindgren, Johnathan Peaster, Sujata Chaudhari, Marat Sadykov, Joselyn Jones, Sameh Mohamadi Abdelghani, Matthew Zimmerman, Kenneth W. Bayles, Greg Somerville, Paul Fey

School of Veterinary and Biomedical Sciences: Faculty Publications

A recent controversial hypothesis suggested that the bactericidal action of antibiotics is due to the generation of endogenous reactive oxygen species (ROS), a process requiring the citric acid cycle (tricarboxylic acid [TCA] cycle). To test this hypothesis, we assessed the ability of oxacillin to induce ROS production and cell death in Staphylococcus epidermidis strain 1457 and an isogenic citric acid cycle mutant. Our results confirm a contributory role for TCA-dependent ROS in enhancing susceptibility of S. epidermidis toward β-lactam antibiotics and also revealed a propensity for clinical isolates to accumulate TCA cycle dysfunctions presumably as a way to tolerate these …

Interferon Inducible Protein Ifi35 Negatively Regulates Rig-I Antiviral Signaling And Supports Vesicular Stomatitis Virus Replication, Anshuman Das, Phat X. Dinh, Debasis Panda, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

In a genome-wide siRNA screen, we recently identified the interferon (IFN) inducible protein 35 (IFI35, also known as IFP35) as a factor required for VSV infection. Studies reported here were conducted to further understand the role and requirement of IFI35 in VSV infection. Consistent with the siRNA screening data, we found that depletion of IFI35 led to reduced VSV replication at the level of viral gene expression. Although no direct interaction of IFI35 with the viral replication machinery was observed, we found that IFI35 negatively regulated the host innate immune response and rescued poly(I:C)-induced inhibition of VSV replication. Promoter-driven reporter …

Characterization Of A Serologic Marker Candidate For Development Of A Live-Attenuated Diva Vaccine Against Porcine Reproductive And Respiratory Syndrome Virus, Hiep Vu, Byungjoon Kwon, Marcelo De Lima, Asit K. Pattnaik, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

DIVA (differentiating infected from vaccinated animals) vaccines have proven extremely useful for control and eradication of infectious diseases in livestock. We describe here the characterization of a serologic marker epitope, so-called epitope-M201, which can be a potential target for development of a live-attenuated DIVA vaccine against porcine reproductive and respiratory syndrome virus (PRRSV). Epitope-M201 is located at the carboxyl terminus (residues 161-174) of the viral M protein. The epitope is highly immunodominant and well-conserved among type-II PRRSV isolates. Rabbit polyclonal antibodies prepared against this epitope are non-neutralizing; thus, the epitope does not seem to contribute to the protective immunity against …

Trex1 Regulates Lysosomal Biogenesis And Interferon-Independent Activation Of Antiviral Genes, Maroof Hasan, James Koch, Dinesh Rakheja, Asit K. Pattnaik, James Brugarolas, Igor Dozmorov, Beth Levine, Edward K. Wakeland, Min Ae Lee-Kirsch, Nan Yan

School of Veterinary and Biomedical Sciences: Faculty Publications

Innate immune sensing of viral nucleic acids triggers type I interferon (IFN) production, which activates interferon-stimulated genes (ISGs) and directs a multifaceted antiviral response. ISGs can also be activated through IFN-independent pathways, although the precise mechanisms remain elusive. Here we found that the cytosolic exonuclease Trex1 regulates the activation of a subset of ISGs independently of IFN. Both Trex1−/− mouse and TREX1-mutant human cells express high levels of antiviral genes and are refractory to viral infections. The IFN-independent activation of antiviral genes in Trex1−/− cells requires STING, TBK1 and IRF3 and IRF7. We also found that Trex1-deficient cells display expanded …

Glutaredoxin-2 Is Required To Control Proton Leak Through Uncoupling Protein-3, Ryan J. Mailloux, Jian Ying Xuan, Brittany Beauchamp, Marjorie F. Lou, Mary-Ellen Harper

School of Veterinary and Biomedical Sciences: Faculty Publications

Glutathionylation has emerged as a key modification required for controlling protein function in response to changes in cell redox status. Recently, we showed that the glutathionylation state of uncoupling protein-3 (UCP3) modulates the leak of protons back into the mitochondrial matrix, thus controlling reactive oxygen species production. However, whether or not UCP3 glutathionylation is mediated enzymatically has remained unknown because previous work relied on the use of pharmacological agents, such as diamide, to alter the UCP3 glutathionylation state. Here, we demonstrate that glutaredoxin-2 (Grx2), a matrix oxidoreductase, is required to glutathionylate and inhibit UCP3. Analysis of bioenergetics in skeletal muscle …

Sequence-Optimized And Targeted Double-Stranded Rna As A Therapeutic Antiviral Treatment Against Infectious Myonecrosis Virus In Litopenaeus Vannamei, J. Dustin Loy, Duan S. Loy, Mark A. Mogler, Bruce Janke, Kurt Kamrud, D. L. Hank Harris, Lyric C. Bartholomay

School of Veterinary and Biomedical Sciences: Faculty Publications

Infectious myonecrosis virus (IMNV) is a significant and emerging pathogen that has a tremendous impact on the culture of the Pacific white shrimp Litopenaeus vannamei. IMNV first emerged in Brazil in 2002 and subsequently spread to Indonesia, causing large economic losses in both countries. No existing therapeutic treatments or effective interventions currently exist for IMNV. RNA interference (RNAi) is an effective technique for preventing viral disease in shrimp. Here, we describe the efficacy of a double-stranded RNA (dsRNA) applied as an antiviral therapeutic following virus challenge. The antiviral molecule is an optimized dsRNA construct that targets an IMNV sequence …

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 …

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 …

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 …

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 …