Virology Commons^™

Revolutionizing Our Understanding Of Specific Platelet-Pathogen Interactions, Hammodah Rawhi Hammodah Alfar

Theses and Dissertations--Molecular and Cellular Biochemistry

Aside from their classical role in maintaining hemostasis, platelets are considered first-line vascular guardians that influence both the innate and adaptive immune systems. This is mediated by either direct interactions with immune cells or through the release of pre-stored cytokines and chemokines upon interacting with pathogens such as viruses. While this establishes platelets as potential players in the response to pathogens, it remains unclear what platelets can do with pathogens and how important that is to immune responses, especially against viruses. Most systemic viremias, such as HIV-1, present with mild thrombocytopenia, which is mediated through several mechanisms such as a …

Role Of Interferon Induced Transmembrane Protein 3 (Ifitm3) And Neural Precursor Cell Expressed Developmentally Down Regulated Protein 4 (Nedd4) In Seneca Virus A (Sva) Replication, Shamiq Aftab

Electronic Theses and Dissertations

In this study, we studied the role of IFITM3 in SVA replication in vitro by silencing the endogenous IFITM3 in NCI-H1299 cells. An average of 1.94-fold increase in SVA VP2 expression and an average of 4.4-fold increase in supernatant virus titer was observed after 24h SVA isolate SD15-26 infection. We have indeed observed an increase in viral mRNA copies by an average of 5-fold in IFITM3 silenced NCI-H1299 cells at 8 hpi indicating that IFITM3 restricts SVA replication post virus attachment and entry. A positive correlation between interferon-alpha induced IFITM3 upregulation and reduced SVA replication was observed. To further confirm …

Role Of Autophagy-Related Genes In Lipid Transport For Efficient Replication Of Tombusviruses, Yuanrong Kang

Theses and Dissertations--Plant Pathology

Tombusviruses are positive-strand RNA viruses, which utilize numerous co-opted host factors and massive de-novo synthesized membrane resources to modify host membranes and form large viral replication organelles (VROs). Among plenty of host cellular processes, autophagy emerges as a potential membrane resource for VROs formation due to its ability to de-novo generate the double membrane structures, known as autophagosomes. Besides, as an important host defense pathway, autophagy is also a target for tombusviruses to prevent its antiviral activities. In this study, I identify the role of key autophagy related genes, Atg11, Atg8, and Atg2, which are involved in autophagosome formation, and …

Social Interactions And Spatial Structure Drive Community Assembly Of Bacterial Biofilm, Matthew C. Bond

Dartmouth College Ph.D Dissertations

Despite the critical nature which microbial communities play in the natural world and human civilization, the breadth of understanding remains shallow. Challenged by scale, high variability between environments, and extensive diversity, microbial ecologists strive to understand connections between a community’s structure and function, as well as the ecological and evolutionary mechanisms underlying observed natural patterning of communities. Biofilms are the predominate mode of growth for microbial communities—characterized by cellular attachment to a surface via a self-produced matrix and heterogeneous structure, often resulting in a primary growth front along the biofilm surface due to differential access to bulk nutrients (cite). This …

Select Gut Microbiota Impede Rotavirus Vaccine Efficacy, Vu L Ngo, Yanling Wang, Yadong Wang, Zhenda Shi, Robert Britton, Jun Zou, Sasirekha Ramani, Baoming Jiang, Andrew T Gewirtz

Faculty, Staff and Students Publications

BACKGROUND & AIMS: The protection provided by rotavirus (RV) vaccines is highly heterogeneous among individuals. We hypothesized that microbiota composition might influence RV vaccine efficacy.

METHODS: First, we examined the potential of segmented filamentous bacteria (SFB) colonization to influence RV vaccine efficacy in mice. Next, we probed the influence of human microbiomes on RV vaccination via administering mice fecal microbial transplants (FMTs) from children with robust or minimal RV vaccine responsiveness. Post-FMT, mice were subjected to RV vaccination followed by RV challenge.

RESULTS: SFB colonization induced a phenotype that was reminiscent of RV vaccine failure (ie, failure to generate RV …

Mfgm-Enriched Whey Displays Antiviral Activity Against Common Pediatric Viruses, Evelien Kramer, Ketki Patil, Vassilis Triantis, Jan A H Bastiaans, Michela Mazzon, Sasirekha Ramani, Tim T Lambers

Faculty, Staff and Students Publications

BACKGROUND: Among the most common mucosal viral infections in infants are rotavirus, one of the main causes of severe gastroenteritis in infants and children up to 5 years, and respiratory syncytial virus (RSV), one of the leading causes of lower respiratory tract infections. Both human milk and bovine milk derived factors may provide protection against mucosal viral infections. More recently, a similar activity of milk derived proteins was suggested for SARS-CoV-2. The goal of the current study was to test antiviral activity of the bovine milkfat globule membrane (MFGM) against rotavirus, RSV and SARS-CoV-2 and to further characterize MFGM-enriched whey …

Age-Associated Temporal Decline In Butyrate-Producing Bacteria Plays A Key Pathogenic Role In The Onset And Progression Of Neuropathology And Memory Deficits In 3×Tg-Ad Mice, Paula M Chilton, Smita S Ghare, Benjamin T Charpentier, Scott A Myers, Aakarsha V Rao, Joseph F Petrosino, Kristi L Hoffman, John C Greenwell, Neetu Tyagi, Jyotirmaya Behera, Yali Wang, Lucy J Sloan, Jingwen Zhang, Christopher B Shields, Gregory E Cooper, Leila Gobejishvili, Scott R Whittemore, Craig J Mcclain, Shirish S Barve

Faculty, Staff and Students Publications

Alterations in the gut-microbiome-brain axis are increasingly being recognized to be involved in Alzheimer's disease (AD) pathogenesis. However, the functional consequences of enteric dysbiosis linking gut microbiota and brain pathology in AD progression remain largely undetermined. The present work investigated the causal role of age-associated temporal decline in butyrate-producing bacteria and butyrate in the etiopathogenesis of AD. Longitudinal metagenomics, neuropathological, and memory analyses were performed in the 3×Tg-AD mouse model. Metataxonomic analyses showed a significant temporal decline in the alpha diversity marked by a decrease in butyrate-producing bacterial communities and a concurrent reduction in cecal butyrate production. Inferred metagenomics analysis …

Inter And Intra-Host Diversity Of Rsv In Hematopoietic Stem Cell Transplant Adults With Normal And Delayed Viral Clearance, Vasanthi Avadhanula, Daniel Paiva Agustinho, Vipin Kumar Menon, Roy F Chemaly, Dimpy P Shah, Xiang Qin, Anil Surathu, Harshavardhan Doddapaneni, Donna M Muzny, Ginger A Metcalf, Sara Javornik Cregeen, Richard A Gibbs, Joseph F Petrosino, Fritz J Sedlazeck, Pedro A Piedra

Faculty, Staff and Students Publications

Respiratory syncytial virus (RSV) infection in immunocompromised individuals often leads to prolonged illness, progression to severe lower respiratory tract infection, and even death. How the host immune environment of the hematopoietic stem cell transplant (HCT) adults can affect viral genetic variation during an acute infection is not understood well. In the present study, we performed whole genome sequencing of RSV/A or RSV/B from samples collected longitudinally from HCT adults with normal (<14 >days) and delayed (≥14 days) RSV clearance who were enrolled in a ribavirin trial. We determined the inter-host and intra-host genetic variation of RSV and the effect of …

Vaccines Against Extraintestinal Pathogenic Escherichia Coli (Expec): Progress And Challenges, Ling Qiu, Dylan Chirman, Justin R Clark, Yikun Xing, Haroldo Hernandez Santos, Ellen E Vaughan, Anthony W Maresso

Faculty, Staff and Students Publications

The emergence of antimicrobial resistance (AMR) is a principal global health crisis projected to cause 10 million deaths annually worldwide by 2050. While the Gram-negative bacteria Escherichia coli is commonly found as a commensal microbe in the human gut, some strains are dangerously pathogenic, contributing to the highest AMR-associated mortality. Strains of E. coli that can translocate from the gastrointestinal tract to distal sites, called extraintestinal E. coli (ExPEC), are particularly problematic and predominantly afflict women, the elderly, and immunocompromised populations. Despite nearly 40 years of clinical trials, there is still no vaccine against ExPEC. One reason for this is …

Understanding Cellular Dynamics: Investigating A Yeast-Two Hybrid Protein-Protein Interaction, Riok3:Cse1l; Also By Investigating Trogocytosis Of Cd4+ T Cells From Rhog-/- Mice, Brittnee N. Crane

Graduate Student Theses, Dissertations, & Professional Papers

Rift Valley fever virus (RVFV) is a negative-sense virus that was first described in 1930 when it was isolated from sheep during an outbreak. In the last 25 years there has been a spread in the geographical range into the Middle East. The most susceptible animals are cattle, goats, sheep, and camels. The most overt symptom of livestock infection is that infected pregnant animals experience spontaneous abortion. Humans are susceptible as well and symptoms range from mild febrile illness to liver necrosis, blindness, hemorrhagic fever, and death. An important player in the cellular innate response to RVFV infections is the …

Sars-Cov-2 Immunogenicity Models Inform Novel Strategies That Can Improve Mrna Vaccines, Katherine S. Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

The onset of the 2020 COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, issued a call to action in the fields of biomedical science and public health to implement strategies to contain and protect against the viral threat. In record times, pharmaceutical companies produced antiviral therapies and novel mRNA vaccines that were approved by the FDA for human use. With time, these vaccines were able to assist in ending the pandemic. However, time also showed the limits of mRNA vaccine induced immunity. Despite antibody responses being initially robust, titers dramatically wane with time and are limited in cross-neutralizing ability. As …

Investigating The Role And Mechanism Of Host Cell Death In Porcine Reproductive And Respiratory Virus Infection, Michelle Steyn

Electronic Theses and Dissertations

No abstract provided.

Tim/Tam Receptors: A Potential Biomarker For Predicting Sensitivity To Zika Virus-Induced Oncolysis In Non-Small Cell Lung Cancers, Shankari Somasekar

Honors Undergraduate Theses

Non-small cell lung cancers (NSCLC) constitute 80-85% of lung cancers and are the leading cause of cancer-related deaths globally. The most common cause is prolonged smoking. Current treatment options for NSCLC include surgery, radiation, chemotherapy, targeted drug therapy, and immunotherapy. Although these medications are effective in the short term, patients often face issues of drug resistance and debilitating side effects with prolonged use. Currently, the use of Zika virus (ZIKV) is being researched as a possible alternative treatment for cancer, which minimizes side effects and the risk of drug resistance. TIM/TAM proteins are identified as the putative ZIKV receptors on …

Understanding The Effect Of Chikungunya Virus Infection On Bone Homeostasis, Enakshi Roy

Theses & Dissertations

Chikungunya virus (CHIKV) is a mosquito-borne virus that causes Chikungunya fever (CHIKF), characterized by high fever, headache, rash, and joint pain. With global travel on the rise, infections caused by CHIKV have emerged in new regions, expanding their geographic range and infecting susceptible hosts. Currently, no approved prophylactic or therapeutic measures exist to prevent or treat these infections, with prevention strategies primarily focused on vector control. However, these measures have proven inadequate due to the emergence of mutations that enhance viral transmission or vector range. Therefore, urgent attention is needed to develop therapies to treat the infection. Although CHIKV has …

Establishing A Novel Lipid-Polyamine Metabolic Connection To Virus Replication, Yazmin Edith Cruz Pulido

Dissertations

Polyamines are small positively charged alkylamines found in all living cells. These ubiquitous molecules have been found to play a variety of roles ranging from stabilizing nucleic acids (DNA and RNA) to cellular proliferation. Studies have also identified roles for polyamines in viral packaging and viral enzyme function. However, the role of polyamines on cellular components and their effect on viral replication is less known. In our efforts to identify the lipid-polyamine metabolic connection to virus replication we utilized a human hepatocyte cell line in which polyamines were depleted via pharmacological or genetic approaches and studied the effects on lipid …

Increased Coding Potential Of Bovine Herpesvirus 1, Victoria Jefferson

Theses and Dissertations

Bovine respiratory disease (BRD) costs the cattle industry millions of dollars in costs in treatment and loss every year in the United States. A significant pathogen often contributes to BRD is Bovine Herpesvirus 1 (BoHV-1), a double stranded DNA virus with the ability to establish latency in the trigeminal ganglia and neurons. Primary infection with BoHV-1 results in immunosuppression that increases the risk of secondary bacterial infection and pneumonia. Because herpesviruses infect their hosts for life and can be reactivated in times of stress, BoHV-1 can present a recurring risk of BRD. The following research aims to expand the knowledge …

Ecohiv-Infected Mice Show No Signs Of Platelet Activation, Hammodah Rawhi Hammodah Alfar, Dominic Ngima Nthenge-Ngumbau, Kathryn E. Saatman, Sidney W. Whiteheart

Saha Cardiovascular Research Center Faculty Publications

Platelets express several surface receptors that could interact with different viruses. To understand the mechanisms of HIV-1′s interaction with platelets, we chose the EcoHIV model. While EcoHIV is an established model for neuroAIDS, its effects on platelets are ill-defined. Our results indicate that EcoHIV behaves differently from HIV-1 and is cleared from circulation after 48 h post- infection. The EcoHIV course of infection resembles an HIV-1 infection under the effects of combined antiretroviral therapy (cART) since infected mice stayed immunocompetent and the virus was readily detected in the spleen. EcoHIV-infected mice failed to become thrombocytopenic and showed no signs of …

Developing Disinfection Strategies For Controlling Human Norovirus, Sars-Cov-2, And Clostridioides Difficile Endospores In Long-Term Care Facilities, Jinge Huang

All Dissertations

Long-term care facilities (LTCFs) provide an environment favorable for the transmission of three critical human pathogens: human norovirus (HuNoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and Clostridioides difficile. Given residents in LTCFs are susceptible to infections due to their advanced ages and compromised immune systems, effective environmental surface disinfection plays a crucial role in controlling the spread of human pathogens within these settings and, therefore, mitigates the risk of infections caused by these pathogens. This dissertation aimed to assess the efficacy of various types of disinfectants against two HuNoV surrogates [feline calicivirus (FCV) and Tulane virus (TuV)], two …

Microbial Stimulation Of Oxytocin Release From The Intestinal Epithelium Via Secretin Signaling, Heather A Danhof, Jihwan Lee, Aanchal Thapa, Robert A Britton, Sara C Di Rienzi

Faculty, Staff and Students Publications

Intestinal microbes impact the health of the intestine and organs distal to the gut. Limosilactobacillus reuteri is a human intestinal microbe that promotes normal gut transit, the anti-inflammatory immune system, wound healing, normal social behavior in mice, and prevents bone reabsorption. Oxytocin impacts these functions and oxytocin signaling is required for L. reuteri-mediated wound healing and social behavior; however, the events in the gut leading to oxytocin stimulation and beneficial effects are unknown. Here we report evolutionarily conserved oxytocin production in the intestinal epithelium through analysis of single-cell RNA-Seq datasets and imaging of human and mouse intestinal tissues. Moreover, …

Lactic Acid Bacterial Surface Display Of Scytovirin Inhibitors For Anti-Ebolavirus Infection, Joshua Wiggins, Ngan Nguyen, Wenzhong Wei, Leah Liu Wang, Haley Hollingsead Olson, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

Scytovirin (SVN) is a lectin from cyanobacteria which has a strong inhibitory activity against Ebola virus infection. We engineered scytovirin as the inhibitor for surface display of lactic acid bacteria to block Ebola virus infection. Two different bacterial strains (Lactobacillus casei and Lactococcus lactis) were successfully engineered for scytovirin expression on the bacterial surface. These bacteria were found to be effective at neutralizing pseudotyped Ebolavirus in a cell-based assay. This approach can be utilized for prophylactic prevention, as well as for treatment. Since lactic acid bacteria can colonize the human body, a long-term efficacy could be achieved. Furthermore, …