Virology Commons^™

Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia Parker, Robert Ricklefs

Biology Department Faculty Works

BackgroundPrevious studies have shown that haemosporidian parasites (Haemoproteus(Parahaemoproteus) and Plasmodium) infecting passerine birds have an evolutionary history of host switching with little cospeciation, in particular at low taxonomic levels (e.g., below the family level), which is suggested as the main speciation mechanism of this group of parasites. Recent studies have characterized diverse clades of haemosporidian parasites (H. (Haemoproteus) and H. (Parahaemoproteus)) infecting non-passerine birds (e.g., Columbiformes, Pelecaniiformes). Here, we explore the cospeciation history of H. (Haemoproteus) and H. (Parahaemoproteus) parasites with their non-passerine hosts.MethodsWe sequenced the mtDNA cyt b gene of both haemosporidian parasites and their avian non-passerine hosts. We …

Role Of Viral And Host Factors In Influenza Virus Mediated Inhibition Of Interleukin-23, Ashish Tiwari

Theses and Dissertations--Veterinary Science

Influenza virus is one of the major respiratory pathogens of humans as well as animals, including equines. There is an increasing evidence that bacterial infections are the most common cause of the death during influenza. In horses also, secondary bacterial pneumonia can lead to death, and surviving horses may take up to six months for the complete recovery resulting in heavy economic loss to the equine industry. Interleukin (IL)-23 mediated innate immune response has been shown to protect the host from various respiratory bacterial infections. However, studies to investigate the role of host and viral factors in the regulation of …

Coronavirus Proteases As Therapeutic Targets: Development Of Biosensors To Detect Inhibition Of Protease Activity And Separation Of The Multiple Functions Of Coronavirus Papain-Like Proteases, Andrew Kilianski

Dissertations

Coronaviruses are important human pathogens and have the potential to severely impact public health on an international scale. The emergence of SARS-CoV and MERS-CoV highlight the need for research to identify antivirals and vaccines against coronaviruses. To develop therapeutics against current and potentially emergent coronaviruses, I utilized two approaches targeting the proteases encoded within all coronaviruses. The papain-like protease and 3C-like protease of coronaviruses are responsible for cleaving viral polyproteins early during infection, and this step is required for viral replication. To quantitatively assess the inhibition by small-molecule compounds on MERS-CoV protease activity, I developed a luciferase-based biosensor to monitor …

Virus Purification, Detection And Removal, Khrupa Saagar Vijayaragavan

Dissertations, Master's Theses and Master's Reports - Open

The biopharmaceutical industry has a growing demand and an increasing need to improve the current virus purification technologies, especially as more and more vaccines are produced from cell-culture derived virus particles. Downstream purification strategies can be expensive and account for 70% of the overall manufacturing costs. The economic pressure and purification processes can be particularly challenging when the virus to be purified is small, as in our model virus, porcine parvovirus (PPV). Our efforts are focused on designing an easy, economical, scalable and efficient system for virus purification, and we focused on aqueous two-phase systems. Industry acceptable standards for virus …

Gastroenteritis Viruses In Ireland: Epidemiology And Evolution, Lynda Gunn

Theses

Viral gastroenteritis is a common disease of both humans and animals. This thesis focuses on the use of classical virology, coupled with phylogenetics to study gastroenteritis viruses [Bocavirus (BoV), Coronavirus (CoV), and Rotavirus A (RVA)], isolated from selected samples from humans and animals. RVA was associated with outbreaks in elderly care facilities in Northern Ireland, isolates were genotyped and we reported the first detection of G2 lineage lie RVA in Ireland, with other common human RVA genotypes G1P[8], G2P[4] and G9P[8]. Evolutionary dynamics of human RVA VP7 genotypes was examined using codon models of evolution, results show heterogeneous selective pressure …

Live Siv Vaccine Correlate Of Protection: Immune Complex-Inhibitory Fc Receptor Interactions That Reduce Target Cell Availability, Anthony J. Smith, Stephen W. Wietgrefe, Liang Shang, Cavan S. Reilly, Peter J. Southern, Katherine E. Perkey, Lijie Duan, Heinz Kohler, Sybille Muller, James Robinson, John V. Carlis, Qingsheng Li, R. Paul Johnson, Ashley T. Haase

Nebraska Center for Virology: Faculty Publications

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to

protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by

identifying correlates of the robust protection associated with SIV_mac239Δnef vaccination in the

SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one

correlate of SIV_mac239Δnef protection against vaginal challenge as a resident mucosal system for

SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of

these antibodies on the path of virus entry to inhibit establishment of infected founder populations

at the …

Characterizing Dsrna Production In Virus-Infected Fish Cells, Amal Brek Aloufi

Theses and Dissertations (Comprehensive)

Viral dsRNA is produced by almost all viruses sometime during their replicative cycle. These viral nucleic acids are potent inducers of both innate and adaptive immune responses, and are therefore considered important immuno-modulators. Previous studies have shown that viruses produce dsRNA when replicating in mammalian cells; however, to date no one has demonstrated viral dsRNA production in virus infected fish cells. Therefore, the goal of this study is to investigate dsRNA production by fish viruses in fish cells, verifying production and performing initial characterization of the dsRNA molecules being produced. Three different rainbow trout cell lines were used in this …

The Innate Antiviral Effects Of Extracellular Viral Dsrna In Rainbow Trout Cells, Sarah J. Poynter

Theses and Dissertations (Comprehensive)

Viral double-stranded RNA (dsRNA) molecules are a potent pathogen-associated molecular pattern and play a crucial role in the innate immune response. During a viral infection, extracellular and intracellular dsRNA can initiate pathways resulting in the production of type I interferons (IFNs) and interferon-stimulated genes (ISGs). The accumulation of ISGs within a cell results in a protective antiviral state. This study used both commercially available dsRNA (poly I:C) and in vitro transcribed dsRNA molecules, based on the viral hemorrhagic septicemia virus (VHSV) genome sequence, as stimuli to investigate the effects of these molecules on the innate immune response in rainbow trout …

The Burden Of Avian Influenza Viruses In Community Ponds In California, Zin Htway

Walden Dissertations and Doctoral Studies

Emerging influenza viruses continue to challenge public health. The problem is public health science professionals have been battling emerging human influenza diseases with tactile and reactionary methods because there is a lack of knowledge and data at the human-animal interface. This research was a baseline study of the proportion of influenza A virus (IAV) in urban and rural communities in California. The population was artificial recirculating water ponds in the geographic locations of rural and urban Californian communities. Surface water samples [N = 182] were collected from artificial recirculating ponds in California. Positivity for IAV was verified by real time …

The Sumoylation Of The Non-Structural Protein 1 Of The Influenza A Virus Plays A Dual Role During Viral Infection, Jason Michael Chacon

Open Access Theses & Dissertations

The potential for a highly pathogenic influenza pandemic remains a concern for global health. The ability of the influenza virus to undergo antigenic shift and genetic drift give circulating strains of influenza the high probability of developing resistance to current antiviral therapies. Emerging strains of higher virulence, to which the infected person has not had any previous exposure to viral antigens, pose a greater threat of serious illness and death. Currently, there is no antiviral therapy that is effective against all strains of influenza, emphasizing the need to develop new strategies that target cellular systems required for viral replication to …

Characterization Of Ns1 Sumoylation And Its Effect On Influenza A Viral Infection, Katherine Anne Meraz

Open Access Theses & Dissertations

Influenza virus is a contagious respiratory virus responsible for seasonal epidemics and several catastrophic pandemics in the last century. Its genome is comprised of negative sense, single-stranded RNA and, after entering the cell, it is capable of hijacking the host cellular machinery for reproducing its own genetic material. The activation of cellular defenses against influenza viral infection are triggered upon viral entry and help regulate the course of viral infection. This study focused on the interplay between the influenza A virus and the cellular SUMOylation system during viral infection. The first part of this Dissertation deals with the relevance of …

Sumoylation Affects Ns1'S Ability To Neutralize The Interferon Response, Jeanette Cecilia Gonzalez

Open Access Theses & Dissertations

It is of huge concern the possibility that at some point in the future we may face a new pandemic involving a highly pathogenic virus due to our current preventive and treatment options to fight this viral disease. The main reason for such limitations is the ability of the virus to go over constant antigenic shifts and drifts on its viral surface proteins HA and NA. The constant mutations that affect this virus cause the need of developing new vaccines for each influenza season. Periodically, the World Health Organization (WHO) reports that around 10% of the world population gets infected …

Host Proteins Interact With The Hiv-1 Core To Facilitate And Restrict, Zana Lukic

Dissertations

Host cell proteins, termed restriction factors, which inhibit viral replication at various stages of the viral life cycle, determine the species-specific tropism of numerous retroviruses. Many members of the TRIM family of proteins act as viral restriction factors. One well-characterized example is the ability of TRIM5á from rhesus macaques (rhTRIM5á) to inhibit human immunodeficiency virus type-1 (HIV-1) soon after viral entry but prior to reverse transcription (RT). It is well established that the restriction requires an interaction between the viral capsid lattice and the B30.2/SPRY domain of TRIM5á. Following the binding of the viral core, TRIM5á mediates an event or …

Adenovirus Vectors As Potent Adjuvants In Vaccine Development, Kathleen Ann Mcguire

Dissertations

Due to their ability to activate the immune system, replication-defective Adenoviruses (Ad) are potential vaccine vectors for several pathogens. The proinflammatory response to Ad contributes to the response to vaccine antigens. We found that reactive oxygen species (ROS) are an important signal in the proinflammatory response to Ad. We identified that serotype 5 adenovirus (Ad5) elicits ROS by inducing mitochondrial membrane damage, a process that is dependent on endosomal membrane rupture and Cathepsin release. This mitochondrial dysfunction contributes to NLRP3 inflammasome- and NFκB-dependent innate immune activation. The ROS-dependent inflammatory response likely contributes to the adaptive immune response by supporting DC …

Reconsidering The Model Of Trim5Α Assembly: The Role Of The Linker2 (L2) Region In Trim5Α Assembly, Laura Johnsen

Master's Theses

The TRIM5α protein from rhesus macaques (TRIM5αrh) exhibits a remarkable ability to potently inhibit infection by Human Immunodeficiency Virus Type-1 (HIV-1). Extensive studies have shown that TRIM5α is capable of self-associating at many levels, eventually leading to the formation of a hexameric assembly that can superimpose on the hexameric lattice of the HIV-1 capsid. The mechanism underlying the self-association of TRIM5α and the molecular determinants of self-association remain to be completely understood. In this study, we show that the Linker 2 (L2) region of TRIM5rh is important for dimerization and higher order self-association, both of which are independent processes. Additionally, …

Multifunctional Coronavirus Papain-Like Proteases As Targets For Antiviral Therapeutics And Vaccines, Anna Maria Mielech

Dissertations

Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and Middle Ease Respiratory Syndrome coronavirus (MERS-CoV) pose a severe threat to humans because of high mortality. Despite the risk of coronavirus (CoV) emerging in the human population there are no antiviral drugs or vaccines to combat coronavirus infection. The focus of my dissertation was to study the multifunctionality of papain-like proteases (PLPs) encoded within coronavirus genomes to facilitate the development of antiviral drugs and vaccines. The viral PLPs are critical for processing the amino-terminal end of the replicase during virus replication and are attractive targets for antiviral therapies.

In my research, I analyzed …

Characterization Of A Dual-Tropic Human Immunodeficiency Virus (Hiv-1) Strain Derived From The Prototypical X4 Isolate Hxbc2, Shi-Hua Xiang, Beatriz Pacheco, Dane Bowder, Wen Yuan, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Human immunodeficiency virus type 1 (HIV-1) coreceptor usage and tropism can be modulated by the V3 loop sequence of the gp120 exterior envelope glycoprotein. For coreceptors, R5 viruses use CCR5, X4 viruses use CXCR4, and dual-tropic (R5X4) viruses use either CCR5 or CXCR4. To understand the requirements for dual tropism, we derived and analyzed a dual-tropic variant of an X4 virus. Changes in the V3 base, which allow gp120 to interact with the tyrosine-sulfated CCR5 N-terminus, and deletion of residues 310/311 in the V3 tip were necessary for efficient CCR5 binding and utilization. Thus, both sets of V3 changes allowed …

Risk Factors For Early Childhood Infection Of Human Herpesvirus-8 In Zambian Children: The Role Of Early Childhood Feeding Practices, Kay L. Crabtree, Janet M. Wojcicki, Veenu Minhas, David R. Smith, Chipepo Kankasa, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Background—Human herpesvirus-8 (HHV-8) infection in early childhood is common throughout sub-Saharan Africa with prevalence increasing throughout childhood. Specific routes of transmission have not been clearly delineated, though HHV-8 is present in high concentrations in saliva.

Methods—To understand the horizontal transmission of HHV-8 within households to children we enrolled for cross-sectional analysis, 251 households including 254 children, age two and under, in Lusaka, Zambia. For all children, plasma was screened for HHV-8 and HIV-1 and health and behavioral questionnaires were completed. Multi-level logistic regression analysis was conducted to assess independent factors for HHV-8 infection in children.

Results—Risk factors for HHV-8 infection …

Review Of Epidemiology And Transmission Of Kaposi’S Sarcoma-Associated Herpesvirus, Veenu Minhas, Charles Wood

Nebraska Center for Virology: Faculty Publications

This review summarizes the current knowledge pertaining to Kaposi sarcoma-associated herpesvirus (KSHV) epidemiology and transmission. Since the identification of KSHV twenty years ago, it is now known to be associated with Kaposi’s sarcoma (KS), primary effusion lymphoma, and multicentric Castleman’s disease. Many studies have been conducted to understand its epidemiology and pathogenesis and their results clearly show that the worldwide distribution of KSHV is uneven. Some geographical areas, such as sub-Saharan Africa, the Mediterranean region and the Xinjiang region of China, are endemic areas, but Western Europe and United States have a low prevalence in the general population. This makes …

Seroprevalence Of Human Herpesvirus 8 And Hepatitis C Virus Among Drug Users In Shanghai, China, Tiejun Zhang, Ying Liu, Yuyan Zhang, Jun Wang, Veenu Minhas, Charles Wood, Na He

Nebraska Center for Virology: Faculty Publications

To elucidate and compare the seroprevalence of human herpesvirus 8 (HHV8) and hepatitis C virus (HCV) among Chinese drug users, a cross-sectional study of 441 participants, was conducted in Shanghai, China, from 2012 through 2013. Seventy-seven (17.5%) participants were found to be positive for HHV8 antibodies, while 271 (61.5%) participants were positive for HCV. No significant association between HHV8 seropositivity and drug use characteristics, sexual behaviors, HCV, or syphilis was observed. In contrast, a statistically significant association between HCV seropositivity and injected drug history (OR, 2.18, 95% CI 1.41–3.37) was detected, whereas no statistically significant association between HCV seropositivity and …