Matching Items (11)
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- All Subjects: Immunology
- All Subjects: Animal Physiology
- Creators: Jacobs, Bertram L
Description
The concept of vaccination dates back further than Edward Jenner's first vaccine using cowpox pustules to confer immunity against smallpox in 1796. Nevertheless, it was Jenner's success that gave vaccines their name and made vaccinia virus (VACV) of particular interest. More than 200 years later there is still the need to understand vaccination from vaccine design to prediction of vaccine efficacy using mathematical models. Post-exposure vaccination with VACV has been suggested to be effective if administered within four days of smallpox exposure although this has not been definitively studied in humans. The first and second chapters analyze post-exposure prophylaxis of VACV in an animal model using v50ΔB13RMγ, a recombinant VACV expressing murine interferon gamma (IFN-γ) also known as type II IFN. While untreated animals infected with wild type VACV die by 10 days post-infection (dpi), animals treated with v50ΔB13RMγ 1 dpi had decreased morbidity and 100% survival. Despite these differences, the viral load was similar in both groups suggesting that v50ΔB13RMγ acts as an immunoregulator rather than as an antiviral. One of the main characteristics of VACV is its resistance to type I IFN, an effect primarily mediated by the E3L protein, which has a Z-DNA binding domain and a double-stranded RNA (dsRNA) binding domain. In the third chapter a VACV that independently expresses both domains of E3L was engineered and compared to wild type in cells in culture. The dual expression virus was unable to replicate in the JC murine cell line where both domains are needed together for replication. Moreover, phosphorylation of the dsRNA dependent protein kinase (PKR) was observed at late times post-infection which indicates that both domains need to be linked together in order to block the IFN response. Because smallpox has already been eradicated, the utility of mathematical modeling as a tool for predicting disease spread and vaccine efficacy was explored in the last chapter using dengue as a disease model. Current modeling approaches were reviewed and the 2000-2001 dengue outbreak in a Peruvian region was analyzed. This last section highlights the importance of interdisciplinary collaboration and how it benefits research on infectious diseases.
ContributorsHolechek, Susan A (Author) / Jacobs, Bertram L (Thesis advisor) / Castillo-Chavez, Carlos (Committee member) / Frasch, Wayne (Committee member) / Hogue, Brenda (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2011
Description
CD8+ T-lymphocytes (CTLs) are central to the immunologic control of infections and are currently at the forefront of strategies that enhance immune based treatment of a variety of tumors. Effective T-cell based vaccines and immunotherapies fundamentally rely on the interaction of CTLs with peptide-human leukocyte antigen class I (HLA-I) complexes on the infected/malignant cell surface. However, how CTLs are able to respond to antigenic peptides with high specificity is largely unknown. Also unknown, are the different mechanisms underlying tumor immune evasion from CTL-mediated cytotoxicity. In this dissertation, I investigate the immunogenicity and dysfunction of CTLs for the development of novel T-cell therapies. Project 1 explores the biochemical hallmarks associated with HLA-I binding peptides that result in a CTL-immune response. The results reveal amino acid hydrophobicity of T-cell receptor (TCR) contact residues within immunogenic CTL-epitopes as a critical parameter for CTL-self
onself discrimination. Project 2 develops a bioinformatic and experimental methodology for the identification of CTL-epitopes from low frequency T-cells against tumor antigens and chronic viruses. This methodology is employed in Project 3 to identify novel immunogenic CTL-epitopes from human papillomavirus (HPV)-associated head and neck cancer patients. In Project 3, I further study the mechanisms of HPV-specific T-cell dysfunction, and I demonstrate that combination inhibition of Indoleamine 2, 3-dioxygenase (IDO-1) and programmed cell death protein (PD-1) can be a potential immunotherapy against HPV+ head and neck cancers. Lastly, in Project 4, I develop a single-cell assay for high-throughput identification of antigens targeted by CTLs from whole pathogenome libraries. Thus, this dissertation contributes to fundamental T-cell immunobiology by identifying rules of T-cell immunogenicity and dysfunction, as well as to translational immunology by identifying novel CTL-epitopes, and therapeutic targets for T-cell immunotherapy.
onself discrimination. Project 2 develops a bioinformatic and experimental methodology for the identification of CTL-epitopes from low frequency T-cells against tumor antigens and chronic viruses. This methodology is employed in Project 3 to identify novel immunogenic CTL-epitopes from human papillomavirus (HPV)-associated head and neck cancer patients. In Project 3, I further study the mechanisms of HPV-specific T-cell dysfunction, and I demonstrate that combination inhibition of Indoleamine 2, 3-dioxygenase (IDO-1) and programmed cell death protein (PD-1) can be a potential immunotherapy against HPV+ head and neck cancers. Lastly, in Project 4, I develop a single-cell assay for high-throughput identification of antigens targeted by CTLs from whole pathogenome libraries. Thus, this dissertation contributes to fundamental T-cell immunobiology by identifying rules of T-cell immunogenicity and dysfunction, as well as to translational immunology by identifying novel CTL-epitopes, and therapeutic targets for T-cell immunotherapy.
ContributorsKrishna, Sri (Author) / Anderson, Karen S (Thesis advisor) / LaBaer, Joshua (Committee member) / Jacobs, Bertram L (Committee member) / Lake, Douglas F (Committee member) / Arizona State University (Publisher)
Created2017
Description
White-nose syndrome (WNS) is a fungal infection devastating bat populations throughout eastern North America. WNS is caused by a fungus, Pseudogymnoascus destructans (Pd), that invades the skin of hibernating bats. While there are a number of treatments being researched, there is currently no effective treatment for WNS that is deployed in the field, except a few being tested on a limited scale. Bats have lowered immune function and response during hibernation, which may increase susceptibility to infection during the winter months. Antimicrobial peptides (AMPs) are a crucial component of the innate immune system and serve as barriers against infection. AMPs are constitutively expressed on skin and facilitate wound healing, stimulate other immune responses, and may also stay active on bat skin during hibernation. AMPs are expressed by all tissues, have direct killing abilities against microbes, and are a potential treatment for bats infected with Pd. In this investigation, the fungicidal activity of several readily available commercial AMPs were compared, and killing assay protocols previously investigated by Frasier and Lake were replicated to establish a control trial for use in future killing assays. Another aim of this investigation was to synthesize a bat-derived AMP for use in the killing assay. Sequences of bat-derived AMPs have been identified in bat skin samples obtained from a large geographic sampling of susceptible and resistant species. Contact was made with GenScript Inc., the company from which commercially available AMPs were purchased, to determine the characteristics of peptide sequences needed to synthesize an AMP for lab use. Based on recommendations from GenScript Inc., peptide sequences need to have a hydrophobicity of less than 50% and a sequence length of less than 50 amino acids. These criteria serve as a potential barrier because none of the known bat-derived sequences analyzed satisfy both of these requirements. The final aim of this study was to generate a conceptual model of the immune response molecules activated when bats are exposed to a fungal pathogen such as Pd. Overall, this work investigated sources of variability between trials of the killing assay, analyzed known bat-derived peptide sequences, and generated a conceptual model that will serve as a guideline for identification of immune response molecules on the skin of bats in future proteomics work.
ContributorsBarton, Madisen L (Author) / Moore, Marianne (Thesis director) / Penton, Christopher (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Phytohemagglutinin (PHA) is a plant lectin commonly used to stimulate and test responses of the immune system and is known to induce T cell proliferation, agglutinate human leukocytes, and yield adjustments in lymphocyte populations. What is not well know is how responses to PHA correlate with a host's ability to resist or recover from pathogen invasion. This study uses information from previously published studies to determine whether or not PHA can be a good indicator of disease severity or disease resistance in a host. With PHA having the abilities that it does, immune responses to PHA may correlate with responses important for pathogen resistance and clearance. Such a relationship could only be uncovered if in vivo or in vitro responses to PHA are measured and, independent from the PHA challenge, symptoms and/or mortality rates of hosts are documented after pathogen exposure. An in vitro response can be detected by measuring cellular proliferation in response to PHA followed by separate cell cultures exposed to a pathogen. While an in vivo response can be detected by measuring variation in swelling in response to an injection of PHA. In reviewing a broad range of articles that meet my criteria, the majority of articles failed to show a strong relationship between PHA and disease severity or disease resistance. Therefore, immunologists must consider the usefulness of the PHA tests as a measure of immunocompetence, which is a host's ability to predict response to a pathogen. According to the literature, using PHA does not predict responses to pathogen invasion. However, it is possible that with carefully designed experiments, it could be determined that PHA does provide an indication of pathogen resistance in certain host species exposed to specific pathogen.
ContributorsMackey, Tracy Michelle (Author) / Moore, Marianne (Thesis director) / Penton, Ryan (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The HIV-1 pandemic continues to cause millions of new infections and AIDS-related deaths each year, and a majority of these occur in regions of the world with limited access to antiretroviral therapy. Therefore, an HIV-1 vaccine is still desperately needed. The most successful HIV-1 clinical trial to date used a non-replicating canarypox viral vector and protein boosting, yet its modest efficacy left room for improvement. Efforts to derive novel vectors which can be both safe and immunogenic, have spawned a new era of live, viral vectors. One such vaccinia virus vector, NYVAC-KC, was specifically designed to replicate in humans and had several immune modulators deleted to improve immunogenicity and reduce pathogenicity. Two NYVAC-KC vectors were generated: one expressing the Gag capsid, and one with deconstructed-gp41 (dgp41), which contains an important neutralizing antibody target, the membrane proximal external region (MPER). These vectors were combined with HIV-1 Gag/dgp41 virus-like particles (VLPs) produced in the tobacco-relative Nicotiana benthamiana. Different plant expression vectors were compared in an effort to improve yield. A Geminivirus-based vector was shown to increase the amount of MPER present in VLPs, thus potentially enhancing immunogenicity. Furthermore, these VLPs were shown to interact with the innate immune system through Toll-like receptor (TLR) signaling, which activated antigen presenting cells to induce a Th2-biased response in a TLR-dependent manner. Furthermore, expression of Gag and dgp41 in NYVAC-KC vectors resulted in activation of antiviral signaling pathways reliant on TBK1/IRF3, which necessitated the use of higher doses in mice to match the immunogenicity of wild-type viral vectors. VLPs and NYVAC-KC vectors were tested in mice, ultimately showing that the best antibody and Gag-specific T cell responses were generated when both components were administered simultaneously. Thus, plant-produced VLPs and poxvirus vectors represent a highly immunogenic HIV-1 vaccine candidate that warrants further study.
ContributorsMeador, Lydia Rebecca (Author) / Mor, Tsafrir S (Thesis advisor) / Jacobs, Bertram L (Thesis advisor) / Blattman, Joseph N (Committee member) / Mason, Hugh S (Committee member) / Arizona State University (Publisher)
Created2016
Description
The interaction between a virus and its host is a constant competition for supremacy. Both the virus and the host immune system constantly evolve mechanisms to circumvent one another. Vaccinia virus (VACV) infections are a prime example of this. VACV contains a highly conserved innate immune evasion gene, E3L, which encodes the E3 protein composed of a Z-NA-binding domain (Z-NA BD) in the N terminus and a highly characterized dsRNA binding domain in the C-terminus. Both domains of E3 have been found to be essential for the inhibition of antiviral states initiated by host type 1 IFNs. However, the mechanism by which the Z-NA-BD of E3’s N-terminus confers IFN resistance has yet to be established. This is partially due to conflicting evidence showing that the Z-NA-BD is dispensable in most cell culture systems, yet essential for pathogenicity in mice. Recently it has been demonstrated that programmed necrosis is an alternative form of cell death that can be initiated by viral infections as part of the host’s innate immune response to control infection. The work presented here reveals that VACV has developed a mechanism to inhibit programmed necrosis. This inhibition occurs through utilizing E3’s N-terminus to prevent the initiation of programmed necrosis involving the host-encoded cellular proteins RIP3 and Z-NA-binding protein DAI. The inhibition of programmed necrosis has been shown to involve regions of both the viral and host proteins responsible for Z-NA binding through in vivo studies demonstrating that deletions of the Z-NA-BD in E3 correspond to an attenuation of pathogenicity in wild type mice that is restored in RIP3- and DAI-deficient models. Together these findings provide novel insight into the elusive function of the Z-NA-binding domain of the N-terminus and its role in preventing host recognition of viral infections. Furthermore, it is demonstrated that a unique mechanism for resisting virally induced programmed necrosis exists. This mechanism, specific to Z-NA binding, involves the inhibition of a DAI dependent form of programmed necrosis possibly by preventing host recognition of viral infections, and hints at the possible biological role of Z-NA in regulating viral infections.
ContributorsHarrington, Heather (Author) / Jacobs, Bertram L (Thesis advisor) / Langland, Jeffery O (Committee member) / Blattman, Joseph (Committee member) / Haydel, Shelly (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2016
Description
Poxviruses such as monkeypox virus (MPXV) are emerging zoonotic diseases. Compared to MPXV, Vaccinia virus (VACV) has reduced pathogenicity in humans and can be used as a partially protective vaccine against MPXV. While most orthopoxviruses have E3 protein homologues with highly similar N-termini, the MPXV homologue, F3, has a start codon mutation leading to an N-terminal truncation of 37 amino acids. The VACV protein E3 consists of a dsRNA binding domain in its C-terminus which must be intact for pathogenicity in murine models and replication in cultured cells. The N-terminus of E3 contains a Z-form nucleic acid (ZNA) binding domain and is also required for pathogenicity in murine models. Poxviruses produce RNA transcripts that extend beyond the transcribed gene which can form double-stranded RNA (dsRNA). The innate immune system easily recognizes dsRNA through proteins such as protein kinase R (PKR). After comparing a vaccinia virus with a wild-type E3 protein (VACV WT) to one with an E3 N-terminal truncation of 37 amino acids (VACV E3Δ37N), phenotypic differences appeared in several cell lines. In HeLa cells and certain murine embryonic fibroblasts (MEFs), dsRNA recognition pathways such as PKR become activated during VACV E3Δ37N infections, unlike VACV WT. However, MPXV does not activate PKR in HeLa or MEF cells. Additional investigation determined that MPXV produces less dsRNA than VACV. VACV E3Δ37N was made more similar to MPXV by selecting mutants that produce less dsRNA. By producing less dsRNA, VACV E3Δ37N no longer activated PKR in HeLa or MEF cells, thus restoring the wild-type phenotype. Furthermore, in other cell lines such as L929 (also a murine fibroblast) VACV E3Δ37N, but not VACV WT infection leads to activation of DNA-dependent activator of IFN-regulatory factors (DAI) and induction of necroptotic cell death. The same low dsRNA mutants demonstrate that DAI activation and necroptotic induction is independent of classical dsRNA. Finally, investigations of spread in an animal model and replication in cell lines where both the PKR and DAI pathways are intact determined that inhibition of both pathways is required for VACV E3Δ37N to replicate.
ContributorsCotsmire, Samantha (Author) / Jacobs, Bertram L (Thesis advisor) / Varsani, Arvind (Committee member) / Hogue, Brenda (Committee member) / Haydel, Shelley (Committee member) / Arizona State University (Publisher)
Created2021
Description
An estimated 267 million women worldwide are HSV-2 seropositive, including roughly 20% of reproductive-aged American women. HSV-2 is a neurotropic virus that establishes a persistent, life-long infection that increases risk for STI acquisition in individuals. The vaginal epithelium represents a critical first line of defense against infection, and during acute infection, underlying immune mechanisms in the epithelium may be critical to protect against disease pathogenesis. The recently identified pro-inflammatory cytokine IL-36gamma has been shown to be expressed at mucosal epithelia, including the female reproductive tract (FRT) and may be an important factor in host defense. Although IL-36gamma has been shown to be induced in the FRT after exposure to microbial products, the contributions of IL-36gamma to host defense mechanisms in response to this clinically relevant STI pathogen are not well understood. This dissertation describes the regulation of IL-36gamma in the FRT and explores its contribution to the host response against genital HSV-2 infection.
To test the hypothesis that IL-36gamma is a key regulator of mucosal inflammation and immunity in the FRT, hormonal regulation of IL-36gamma in the FRT was investigated using estrogen- and progesterone-conditioned mice. From this preliminary study, it was shown that progesterone dampens IL36G expression relative to estrogen and may potentially increase susceptibility to infection. Next, the impact of IL-36gamma treatment on HSV-2 infection and replication in human 3-D vaginal epithelial cells was explored. In parallel, the impact of intravaginal IL-36gamma delivery on HSV-2 disease pathogenesis was evaluated using a lethal murine challenge model. IL-36gamma pre-treatment significantly limited HSV-2 replication in vitro and in vivo and was associated with transient neutrophil infiltration that corresponded with decreased disease severity and increased survival in mice. Last, the requirement for IL-36gamma in host defense was investigated utilizing IL-36gamma-/- mice in a lethal HSV-2 murine challenge model. Following infection, IL-36gamma-/- mice exhibited significantly impaired neutrophil recruitment, decreased overall survival time, and significantly increased viral neuroinvasion relative to wild type mice. Collectively, these data indicate that IL-36gamma is a crucial regulator of HSV-2-induced neutrophil infiltration and appears to function in a previously uncharacterized manner to limit viral neuroinvasion in genital HSV-2 disease pathogenesis.
To test the hypothesis that IL-36gamma is a key regulator of mucosal inflammation and immunity in the FRT, hormonal regulation of IL-36gamma in the FRT was investigated using estrogen- and progesterone-conditioned mice. From this preliminary study, it was shown that progesterone dampens IL36G expression relative to estrogen and may potentially increase susceptibility to infection. Next, the impact of IL-36gamma treatment on HSV-2 infection and replication in human 3-D vaginal epithelial cells was explored. In parallel, the impact of intravaginal IL-36gamma delivery on HSV-2 disease pathogenesis was evaluated using a lethal murine challenge model. IL-36gamma pre-treatment significantly limited HSV-2 replication in vitro and in vivo and was associated with transient neutrophil infiltration that corresponded with decreased disease severity and increased survival in mice. Last, the requirement for IL-36gamma in host defense was investigated utilizing IL-36gamma-/- mice in a lethal HSV-2 murine challenge model. Following infection, IL-36gamma-/- mice exhibited significantly impaired neutrophil recruitment, decreased overall survival time, and significantly increased viral neuroinvasion relative to wild type mice. Collectively, these data indicate that IL-36gamma is a crucial regulator of HSV-2-induced neutrophil infiltration and appears to function in a previously uncharacterized manner to limit viral neuroinvasion in genital HSV-2 disease pathogenesis.
ContributorsGardner, Jameson Kyle (Author) / Herbst-Kralovetz, Melissa M (Thesis advisor) / Lake, Douglas F (Committee member) / Jacobs, Bertram L (Committee member) / Boehmer, Paul E (Committee member) / Hogue, Ian B (Committee member) / Arizona State University (Publisher)
Created2019
Description
Since the molecular biology revolution in the 1980s, ease of gene editing had led to the resurgence of Oncolytic Virotherapy. Countless viruses have been engineered yet only three are approved for clinical use worldwide, with only one being approved by the U.S Food and Drug Administration (FDA). Vaccinia virus (VACV) has a large genome, contains many immune evasion genes and has been thoroughly studied, making it a popular candidate for an oncolytic platform. VACV mutants with deletions in the E3 immune evasion protein have been shown to have oncolytic efficacy but the mechanism of tumor selectivity has not been fully elucidated. These mutants have been shown to be regulated by the necroptosis pathway, a pathway that has been shown to be deficient in certain cancers. Using a pan-cancer screening method that combines dye exclusion assays, western blot analysis, and viral growth curve, the role of necroptosis in regulating VACV replication and oncolytic efficacy in cancer was further characterized. Results demonstrate a preliminary correlation between necroptosis, viral replication, and oncolytic efficacy. This correlation is clearest in breast cancer and melanomas yet may apply to other cancer subgroups. This data was also used to guide the development of a receptor-interacting protein kinase 3 (RIP3) matched pair mouse model in the E0771 mouse breast cancer line which can be used to further study the role of necroptosis and oncolytic efficacy in vivo. Understanding the contribution necroptosis plays in oncolytic efficacy can guide to design enhance the design of clinical trials to test VACV E3L mutants and may lead to better efficacy in humans and an improvement in clinical oncology.
ContributorsKasimsetty, Aradhana (Author) / Jacobs, Bertram L (Thesis advisor) / McFadden, Douglas G (Committee member) / Borad, Mitesh (Committee member) / Arizona State University (Publisher)
Created2020
Description
“Tell It to the Frogs: Fukushima’s nuclear disaster and its impact on the Japanese Tree Frog” is a representation of the work from Giraudeau et. al’s “Carotenoid distribution in wild Japanese tree frogs (Hyla japonica) exposed to ionizing radiation in Fukushima.” This paper looked to see if carotenoid levels in the tree frog’s vocal sac, liver, and blood were affected by radiation from Fukushima’s power plant explosion. Without carotenoids, the pigment that gives the frogs their orange color on their necks, their courtship practices would be impacted and would not be as able to show off their fitness to potential mates. The artwork inspired by this research displayed the tree frog’s degradation over time due to radiation, starting with normal life and ending with their death and open on the table. The sculptures also pinpoint where the carotenoids were being measured with a brilliant orange glaze. Through ceramic hand building, the artist created larger than life frogs in hopes to elicit curiosity about them and their plight. While the paper did not conclude any changes in the frog’s physiology after 18 months of exposure, there are still questions that are left unanswered. Why did these frogs not have any reaction? Could there be any effects after more time has passed? Is radiation leakage as big of a problem as previously thought? The only way to get the answers to these questions is to be aware of these amphibians, the circumstances that led them to be involved, and continued research on them and radiation.
ContributorsWesterfield, Savannah (Author) / Beiner, Susan (Thesis director) / McGraw, Kevin (Committee member) / School of Life Sciences (Contributor) / School of Art (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05