Immunology of Infectious Disease Commons^™

Identifying Correlates Of Protection Of A Pneumonic Plague Vaccine., Caleb Samuel Whitley

Electronic Theses and Dissertations

Pneumonic plague is caused by inhalation of the bacterial pathogen Yersinia pestis. The immune response during Pneumonic plague occurs in two phases; an initial asymptomatic phase followed by a highly inflammatory and destructive phase resulting in 100% mortality if left untreated. The rapid onset of severe disease following the asymptomatic phase makes it difficult to administer antibiotics in time to prevent lethal outcomes. Therefore, the development of an effective vaccine is likely needed to combat pneumonic plague in areas of the world where Y. pestis remains endemic. One candidate subunit vaccine is protective in mice, a natural host for …

Antibody-Induced Multicellular Behaviors Of Salmonella Typhimurium, Samantha K. Lindberg

Electronic Theses & Dissertations (2024 - present)

Salmonella enterica is a globally distributed bacterial pathogen that is commonly acquired through consumption of contaminated food and water. The enterica subspecies includes over 1500 unique subvariants, or serovars, that are classified by antigen presentation. Due to its global environmental prevalence, broad host range, and increasing pathogenicity, serovar Typhimurium is of particular concern for human and animal health, as well as food safety. Once in the gastrointestinal tract, Salmonella Typhimurium (STm) exploits host immune mechanisms, implements an arsenal of virulence factors, and outcompetes the microbiota to invade the intestinal epithelium. While STm infections are generally self-limiting and relatively mild, emerging …

Induction Of Protective Immunity In The Respiratory Tract With Ricin Toxin Immune Complexes, Lindsey Elizabeth Tolman

Legacy Theses & Dissertations (2009 - 2024)

Ricin toxin (RT) is generated in the seeds of Ricinus communis. The highly potent toxin is comprised of two subunits, RTA and RTB. RT enters cells using RTB before RTA separates itself and inactivates the ribosome, inducing cell stress, inflammation, and eventual death. RT is particularly damaging in the respiratory tract, where intoxication induces an inflammatory cytokine storm.Though there are currently no therapeutics for RT intoxication, our group has generated and characterized a wide variety of monoclonal antibodies (mAbs) against RT. Among the top candidates in our collection are the IgGs PB10 and SylH3. Previous studies have demonstrated their exceptional …

Prevalence Of Sars-Cov-2 Antibodies In Liberty University Student Population, Emily Bonus

Senior Honors Theses

In 2020, the virus SARS-CoV-2 gained attention as it spread around the world. Its antibodies are poorly understood, and little research focuses on those with few COVID-19 complications yet large numbers of close contacts: university students. This longitudinal study recorded SARS-CoV-2 antibody presence in 107 undergraduate Liberty University students twice during early 2021. After extensive data cleaning and the application of various statistical tests and ANOVAs, the data seems to show that in the case of COVID-19 infections, SARS-CoV-2 IgM antibodies are immediately produced, and then IgG antibodies follow later. However, the COVID-19 vaccine causes the production of both IgM …

Fine-Mapping Of Human Antibody Specificity In Response To Natural Chlamydia Trachomatis Infection Utilized To Inform Vaccines Against Adhesion Factors, Amanda L. Collar

Biomedical Sciences ETDs

Chlamydia trachomatis (Ct) is the causative pathogen for the most common bacterial sexually transmitted infection worldwide and can cause serious medical consequences in women, including pelvic inflammatory disease, ectopic pregnancy, and infertility. For these reasons, a Ct vaccine is urgently needed, yet, its development remains a significant challenge. One barrier to producing a Ct vaccine is the gap in knowledge of protective immune responses for Ct infection, including the role that antibodies may play. Therefore, I aimed to characterize the human antibody response to natural urogenital Ct infection in women using Deep Sequence-Coupled Biopanning. Further, I leveraged these findings to …

Sarscov-2 Serostatus Amongst Vaccinated Employees At A Pediatric Hospital System, Sridevi Devaraj, Izmarie Poventud-Fuentes, Matthew Girotto, Jermaine Monroe, Julie Boom, George Delclos, James Versalovic

Faculty, Staff and Students Publications

To gain insights on the heterogeneity of immune responses to vaccination against SARS-CoV-2 and to identify factors that could make individuals vulnerable to infection due to lack of response to vaccination, our hospital started offering free voluntary post-antibody testing against the spike protein IgG for all fully vaccinated employees.

Post-vaccination response against SARS-CoV-2 was assessed using the FDA-EUA approved VITROS anti-SARS-CoV-2 IgG immunometric assay specific to the spike protein.

Out of a total of 3266 antibody tests performed in fully vaccinated Texas Children’s, 99.4% had a positive antibody response to the spike protein. From the 21 employees (0.6%) that had …

Passive Immunization Against Invasive Salmonella Enterica, Angelene Richards

Legacy Theses & Dissertations (2009 - 2024)

The Gram-negative bacterium, Salmonella enterica is a prominent etiologic agent of both diarrheal disease and enteric fever that encompasses over 2500 serovars, including S. Typhimurium (STm) and S. Typhi (STy). S. enterica is transmitted through contaminated food and water and, following ingestion, invades the gastrointestinal (GI) mucosa. The bacterium uses flagellar-based motility to target microfold (M) cells overlying gut-associated lymphoid tissues known as Peyer’s patches in the small intestine. Entry into Peyer’s patch tissues is a pivotal step in the infection process, as the bacterium can then disseminate systemically in the host. Given the rise in antibiotic resistance amongst S. …

Intrabodies Reveal Critical Steps Involved In Ricin's Interactions With The Ribosome, Timothy Francis Czajka

Legacy Theses & Dissertations (2009 - 2024)

Ricin is a highly lethal protein toxin derived from the seeds of the castor plant, Ricinus communis. It is a Type II ribosome inactivating protein (RIP), meaning it is a heterodimer with one subunit, ricin toxin B (RTB), that mediates cell surface attachment and intracellular trafficking and a second subunit, ricin toxin A (RTA), that irreversibly shuts down protein synthesis in the cytosol. During trafficking, RTA and RTB necessarily separate in the endoplasmic reticulum, wherein RTA unfolds and translocates into the cytosol where it refolds into an enzymatically active conformation. RTA is remarkably fast acting and efficient, with few molecules …

Adaptation Of Vibrio Cholerae O1 To Protective, Lipopolysaccharide-Specific Antibodies In The Intestinal Lumen, Danielle Elizabeth Baranova

Legacy Theses & Dissertations (2009 - 2024)

The outer membrane (OM) of Gram-negative enteric pathogens like Vibrio cholerae is a barrier against host defense factors, as well as a sensor of physical and chemical stimuli that the bacteria encounter in the gastrointestinal tract. The OM is also the primary target of the mucosal immune response, which consists of secretory antibodies primarily directed against lipopolysaccharide (LPS). ZAC-3 is a monoclonal antibody (MAb) that targets the conserved core/lipid A region of LPS of the pandemic V. cholerae O1 serotype. In a neonatal mouse model, passively administered ZAC-3 IgG has been shown to reduce the ability of V. cholerae to …

Antibody Dependent Enhancement Of Visceral Leishmaniasis, Alan K. Mcnolty

All Master's Theses

Leishmaniasis is a parasitic disease caused by protozoans of the genus Leishmania. This vector-born disease, transmitted by biting phlebotomine sandflies, typically manifests in one of three ways. The cutaneous form of the disease is characterized by localized lesions of the skin and is by far the most common manifestation. The visceral form of the disease is caused by parasitic infiltration of internal organs, particularly the spleen, liver, and bone marrow. The mucocutaneous form is caused by parasitic infection of the mucosa in the nose or mouth. While cutaneous leishmaniasis (CL) is often self-healing, visceral leishmaniasis (VL) is fatal if …

Antibody-Mediated Immunity To Vibrio Cholerae At Epithelial Surfaces, Kara Jeanette Levinson

Legacy Theses & Dissertations (2009 - 2024)

Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has an estimated worldwide disease burden in the millions and remains a significant public health threat. Immunity to V. cholerae is primarily antibody-mediated and though V. cholerae colonization evokes a mucosal immune response, it is the secretory IgA (SIgA) antibodies produced against bacterial surface antigens, specifically lipopolysaccharide (LPS) that confer protective immunity. SIgA antibodies are thought to function by inhibiting colonization by cross-linking and agglutination of pathogens, thereby limiting access to the epithelium, a process known as immune exclusion. Recent studies in other enteric pathogens have demonstrated that SIgA …

Antibody Production During Ehrlichial Infection : Development And Specificity Of T Cell-Independent Igm, Derek Daniel Jones

Legacy Theses & Dissertations (2009 - 2024)

Historically, the role for antibodies in mediating protective immunity against intracellular pathogens was thought to be minimal. However, our previous studies demonstrated that antibodies were both necessary and sufficient to establish protective immunity against Ehrlichia muris, a tick-transmitted intracellular bacterium. The identification of a unique population of CD11c-expressing IgM-secreting plasmablasts in the spleen during early infection of mice led to the appreciation that IgM was a critical component of the humoral immune response, and that IgM was required for control of acute ehrlichial infection. Here, we addressed the generation of the IgM-secreting cells, as well as the properties of the …

Generation And Maintenance Of Protective Igm Responses During Intracellular Bacterial Infection, Rachael Denise Racine

Legacy Theses & Dissertations (2009 - 2024)

It is widely accepted that IgM provides the first line of defense against during microbial infection prior to the generation of high-affinity, isotype-switched antibodies, which is the hallmark of long-lived lived immunity and immunological memory. The overall objective of these studies was to address the role of IgM in the generation and maintenance of protective immunity during intracellular bacterial infection. We have identified a population of CD11clo plasmablasts that were responsible for nearly all of the antigen-specific IgM production in the spleen. Moreover, selective depletion of the CD11c-expressing B cells during acute infection resulted in a complete loss in the …