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- All Subjects: Microbiology
- All Subjects: Biology
- Creators: Lake, Douglas
Description
Infertility has become an increasing problem in developed countries and in many cases can be attributed to compromised sperm quality. Assessment of male fertility typically utilizes semen analysis which mainly examines sperm morphology, however many males whose sperm appear normal are sub- or infertile, suggesting that sperm from these males may be deficient in a protein or suite of proteins. To date, very little is known about the composition of sperm or the complex maturation process that confers motility and fertilization competency to sperm. Chapter 1 discusses the use of whole cell mass spectrometry to identify 1247 proteins comprising the Rhesus macaque (Macaca mulatta) sperm proteome, a commonly used model of human reproduction. This study provides a more robust proxy of human sperm composition than was previously available and facilitates studies of sperm using the rhesus macaque as a model. Chapters 2 & 3 provide a systems level overview of changes in sperm proteome composition that occurs during epididymal transit. Chapter 2 reports the proteomes of sperm collected from the caput, corpus and cauda segments of the mouse epididymis, identifying 1536, 1720 and 1234 proteins respectively. Chapter 3 reports the sperm proteome from four distinct segments of the Rhesus macaque epididymis, including the caput, proximal corpus, distal corpus and cauda, identifying 1951, 2014, 1764 and 1423 proteins respectively. These studies identify a number of proteins that are added and removed from sperm during epididymal transit which likely play an important role in the sperm maturation process. To date no comparative evolutionary studies of sperm proteomes have been undertaken. Chapter 4 compares four mammalian sperm proteomes including the human, macaque, mouse and rat. This study identified 98 proteins common to all four sperm proteomes, 82 primate and 90 rodent lineage-specific proteins and 494, 467, 566, and 193 species specific proteins in the human, macaque, mouse and rat sperm proteomes respectively and discusses how differences in sperm composition may ultimately lead to functional differences across species. Finally, chapter 5 uses sperm proteome data to inform the preliminary design of a rodent contraceptive vaccine delivered orally using recombinant attenuated Salmonella vaccine vectors.
ContributorsSkerget, Sheri Jo (Author) / Karr, Timothy L. (Thesis advisor) / Lake, Douglas (Committee member) / Petritis, Konstantinos (Committee member) / Arizona State University (Publisher)
Created2013
Description
Coccidioidomycosis, also known as Valley Fever, is a disease caused by the dimorphic soil-dwelling fungus, Coccidioides sp. Coccidioidomycosis is difficult to diagnose because symptoms are similar to community-acquired pneumonia. Current diagnostic tests rely on antibody responses, but immune responses can be delayed and aberrant, resulting in false negative diagnoses. Unlike serology, detection of coccidioidal proteins or other fungal components in blood could distinguish valley fever from other pulmonary infections and provide a definitive diagnosis. Using mass spectrometry (LC-MS/MS) we examined the plasma peptidome from patients with serologically confirmed coccidioidomycosis. Mass spectra were searched using the protein database from the Coccidioides species, generated and annotated by the Broad Institute. 15 of 20 patients with serologically confirmed coccidioidomycosis demonstrated the presence of a peptide in plasma, "PGLDSKSLACTFSQV" (PGLD). The peptide is derived from an open reading frame from a "conserved hypothetical protein" annotated with 2 exons, and to date, found only in the C. posadasii strain Silviera RMSCC 3488 genomic sequence. In this thesis work, cDNA sequence analysis from polyadenylated RNA confirms the peptide sequence and genomic location of the peptide, but does not indicate that the intron in the gene prediction of C. posadasii strain Silviera RMSCC 3488 is present. A monoclonal antibody generated against the peptide bound to a 16kDa protein in T27K coccidioidal lysate. Detecting components of the fungus plasma could be a useful diagnostic tool, especially when serology does not provide a definitive diagnosis.
ContributorsDuffy, Stacy Leigh (Author) / Lake, Douglas (Thesis advisor) / Magee, Dewey Mitch (Committee member) / Antwi, Kwasi (Committee member) / Arizona State University (Publisher)
Created2013
Description
Background: Coccidioidomycosis (Valley Fever) is a respiratory disease that is caused by the soil-dwelling fungi Coccidioides immitis and Coccidioides posadasii. Because fungal glycosylation patterns are distinct from mammalian glycosylation patterns, we hypothesized that certain lectins (carbohydrate-binding proteins) might have differential binding properties to coccidioidal glycoproteins, and therefore serve as a tool for the purification and characterization of these glycoproteins from patient specimens. Materials and Methods: To identify potential Coccidioides-binding lectins, lectin-based immunohistochemistry was performed using a panel of 21 lectins on lung tissue from human patients infected with Coccidioides. Enzyme-Linked Immunosorbent Assays (ELISAs) were used to confirm and test candidate Coccidioides-binding lectins for their ability to bind to proteins from antigen preparations of laboratory-grown Coccidioides. Inhibition IHC and ELISAs were used to confirm binding properties of these lectins. SDS-PAGE and mass spectrometry were performed on eluates from coccidioidal antigen preparations run through lectin-affinity chromatography columns to characterize and identify lectin-binding coccidioidal glycoproteins. Results: Two GlcNAc-binding lectins, GSLII and sWGA, bound specifically to spherules and endospores in infected human lung tissue, and not to adjacent lung tissue. The binding of these lectins to both Coccidioides proteins in lung tissue and to coccidioidal antigen preparations was confirmed to have lectin-like characteristics. SDS-PAGE analysis of eluates from lectin-affinity chromatography demonstrated that GSLII and sWGA bind to coccidioidal glycoproteins. Mass spectrometric identification of the top ten lectin affinity-purified glycoproteins demonstrated that GSLII and sWGA share affinity to a common set of coccidioidal glycoproteins. Conclusion: This is the first report of lectins that bind specifically to Coccidioides spherules and endospores in infected humans. These lectins may have the potential to serve as tools for a better method of detection and diagnosis of Valley Fever.
ContributorsChowdhury, Yasmynn (Author) / Lake, Douglas (Thesis director) / Grys, Thomas (Committee member) / Magee, Mitchell (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2015-05
Description
Cancer is one of the leading causes of death in the world and represents a tremendous burden on patients, families and societies. S. Typhimurium strains are specifically attracted to compounds produced by cancer cells and could overcome the traditional therapeutic barrier. However, a major problem with using live attenuated Salmonella as anti-cancer agents is their toxicity at the dose required for therapeutic efficacy, but reducing the dose results in diminished efficacy. In this project, we explored novel means to reduce the toxicity of the recombinant attenuated Salmonella by genetically engineering those virulence factors to facilitate maximal colonization of tumor tissues and reduced fitness in normal tissues. We have constructed two sets of Salmonella strains. In the first set, each targeted gene was knocked out by deletion of the gene. In the second set, the predicted promoter region of each gene was replaced with a rhamnose-regulated promoter, which will cease the synthesis of these genes in vivo, a rhamnose-free environment.
ContributorsBenson, Lee Samuel (Author) / Kong, Wei (Thesis director) / Martin, Thomas (Committee member) / Lake, Douglas (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / Center for Infectious Diseases and Vaccinology (Contributor) / School of Life Sciences (Contributor)
Created2013-05
Description
To combat the global antimalarial resistance crisis effective resistance management strategies are needed. To do so, I need to gain a better understanding of the ecological interactions occurring within malaria infections. Despite the importance of the complex interplay among co-infecting strains, our current knowledge and empirical data of within-host diversity and malaria disease dynamics is limited. In this thesis, I explore the multifaceted dynamics of malaria infections through an ecological lens. My overall research question is: "How do ecological interactions, including niche complementarity, competition dynamics, and the cost of resistance, shape the outcomes of malaria infections, and what implications does this have on understanding and improving resistance management strategies?” In Chapter II, titled “Niche Complementarity in Malaria Infections” I demonstrate that ecological principles are observed in malarial infections by experimentally manipulating the biodiversity of rodent malaria P. chabaudi infections. I observed that some parasites experienced competitive suppression, others experienced competitive facilitation, while others were not impacted. Next, in Chapter III, titled “Determining the Differential Impact of Competition Between Genetically Distinct Plasmodium falciparum Strains” I investigate the differential effect of competition among six genetically distinct strains. The impact of competition varied between strain combinations, and both suppression and facilitation were observed, but most pairings had no competitive interactions. Lastly, in Chapter IV, titled “Assessing Fitness Costs in Malaria Parasites: A Comprehensive Review and Implications for Drug Resistance Management”, I summarize where the field currently stands and what evidence there is for the presence of a fitness cost, or lack thereof, and I highlight the current gaps in knowledge. I found that evidence from field, in vitro, and animal models are overall suggestive of the presence of a fitness cost, however, these costs were not always found. Amid the current focus on malaria eradication, it is crucial to understand the impact of biodiversity on disease severity. By incorporating an ecological approach to infectious disease systems, I can gain insights on within-host interactions and how they impact parasite fitness and transmissibility.
ContributorsSegovia, Xyonane (Author) / Huijben, Silvie (Thesis advisor) / Bean, Heather (Committee member) / Gile, Gillian (Committee member) / Hogue, Ian (Committee member) / Lake, Douglas (Committee member) / Arizona State University (Publisher)
Created2024
Description
Antibodies are naturally occurring proteins that protect a host during infection through direct neutralization and/or recruitment of the innate immune system. Unfortunately, in some infections, antibodies present unique hurdles that must be overcome for a safer and more efficacious antibody-based therapeutic (e.g., antibody dependent viral enhancement (ADE) and inflammatory pathology). This dissertation describes the utilization of plant expression systems to produce N-glycan specific antibody-based therapeutics for Dengue Virus (DENV) and Chikungunya Virus (CHIKV). The Fc region of an antibody interacts with Fcγ Receptors (FcγRs) on immune cells and components of the innate immune system. Each class of immune cells has a distinct action of neutralization (e.g., antibody dependent cell-mediated cytotoxicity (ADCC) and antibody dependent cell-mediated phagocytosis (ADCP)). Therefore, structural alteration of the Fc region results in novel immune pathways of protection. One approach is to modulate the N-glycosylation in the Fc region of the antibody. Of scientific significance, is the plant’s capacity to express human antibodies with homogenous plant and humanized N-glycosylation (WT and GnGn, respectively). This allows to study how specific glycovariants interact with other components of the immune system to clear an infection, producing a tailor-made antibody for distinct diseases. In the first section, plant-produced glycovariants were explored for reduced interactions with specific FcγRs for the overall reduction in ADE for DENV infections. The results demonstrate a reduction in ADE of our plant-produced monoclonal antibodies in in vitro experiments, which led to a greater survival in vivo of immunodeficient mice challenged with lethal doses of DENV and a sub-lethal dose of DENV in ADE conditions. In the second section, plant-produced glycovariants were explored for increased interaction with specific FcγRs to improve ADCC in the treatment of the highly inflammatory CHIKV. The results demonstrate an increase ADCC activity in in vitro experiments and a reduction in CHIKV-associated inflammation in in vivo mouse models. Overall, the significance of this dissertation is that it can provide a treatment for DENV and CHIKV; but equally importantly, give insight to the role of N-glycosylation in antibody effector functions, which has a broader implication for therapeutic development for other viral infections.
ContributorsHurtado, Jonathan (Author) / Chen, Qiang (Thesis advisor) / Arntzen, Charles (Committee member) / Borges, Chad (Committee member) / Lake, Douglas (Committee member) / Arizona State University (Publisher)
Created2019
Description
Vaccines against the arthropod-borne dengue virus (DENV) are still commercially nonexistent. A subunit immunization strategy may be of value, especially if a safe viral vector acts as a biologically active adjuvant. The DENV envelope protein (E), the main target for neutralizing immune responses, has three conformational domains. The immunoglobulin-like and independently folding domain III (DIII) contains epitopes that elicit highly specific neutralizing antibodies. The hepatitis B small surface antigen (HBsAg, S) was used as a scaffold to display DENV 2 DIII on a virus-like particle (VLP). A measles virus (MV) was engineered to vector HBsAg and the hybrid glycoprotein DIII-HBsAg in two different loci (DIII-S). Despite the relatively deleterious effect on replication caused by the insertion of two transcription cassettes, the recombinant virus MVvac2(DIII-S,S)P induced the secretion of DIII-S hybrid VLP with a similar sucrose density as HBsAg particles (1.10-1.12g/ml) and peaked at 48 h post-infection producing 1.3x106 TCID50/ml infectious MV units in vitro. A second recombinant virus, MVvac2(DIII-S)N, was engineered to vector only the hybrid DIII-S. However, it did not induce the secretion of hybrid HBsAg particles in the supernatant of infected cells. The immunogenicity of the recombinant viruses was tested in a MV-susceptible small animal model, the experimental group which received two 105 TCID50 I.P. doses of MVvac2(DIII-S,S)P in a 28 day interval developed a robust immune response against MV (1:1280), HBsAg (787 mIU/ml) and DENV2 (Log10 neutralization index of 1.2) on average. In summary, it is possible to display DENV E DIII on hybrid HBsAg particles vectored by MV that elicit an immune response. This forms the basis for a potential vaccine platform against DENV.
ContributorsHarahap, Indira (Author) / Reyes del Valle, Jorge (Thesis advisor) / Hogue, Brenda G (Thesis advisor) / Lake, Douglas (Committee member) / Mason, Hugh (Committee member) / Arizona State University (Publisher)
Created2015
Description
Coccidioidomycosis (valley fever) is caused by inhalation of arthrospores from soil-dwelling fungi, Coccidioides immitis and C. posadasii. This dimorphic fungus and disease are endemic to the southwestern United States, central valley in California and Mexico. The Genome of Coccidioidies has been sequenced but proteomic studies are absent. To address this gap in knowledge, we generated proteome of Spherulin (lysate of Spherule phase) using LC-MS/MS and identified over 1300 proteins. We also investigated lectin reactivity to spherules in human lung tissue based on the hypothesis that coccidioidal glycosylation is different from mammalian glycosylation, and therefore certain lectins would have differential binding properties to fungal glycoproteins. Lectin-based immunohistochemistry using formalin-fixed paraffin-embedded human lung tissue from human coccidioidomycosis patients demonstrated that Griffonia simplificonia lectin II (GSL II) and succinylated wheat germ agglutinin (sWGA) bound specifically to endospores and spherules in infected lungs, but not to adjacent human tissue. GSL II and sWGA-lectin affinity chromatography using Spherulin, followed by LC-MS/MS was used to isolate and identify 195 proteins that bind to GSL-II lectin and 224 proteins that bind to sWGA lectin. This is the first report that GSL II and sWGA lectins bind specifically to Coccidioides endospores and spherules in infected human tissues. Our list of proteins from spherulin (whole and GSL-II and sWGA binding fraction) may also serve as a Coccidioidal Rosetta-Stone generated from mass spectra to identify proteins from 3 different databases: The Broad Institutes Coccidioides Genomes project, RefSeq and SwissProt. This also serves as a viable avenue for proteomics based diagnostic test development for valley fever. Using lectin chromatography and LC MS/MS, we identified over 100 proteins in plasma of two patients and six proteins in urine of one patient. We also identified over eighty fungal proteins isolated from spherules from biopsied infected lung tissue. This, to the best of our knowledge, is the first such example of detecting coccidioidal proteins in patient blood and urine and provides a foundation for development of a proteomics based diagnostic test as opposed to presently available but unreliable serologic diagnostic tests reliant on an antibody response in the host.
ContributorsKaushal, Setu (Author) / Lake, Douglas (Thesis advisor) / Magee, Dewey Mitchell (Committee member) / Chandler, Douglas (Committee member) / Rawls, Jeffery (Committee member) / Arizona State University (Publisher)
Created2015
Description
Measles is a contagious, vaccine-preventable disease that continues to be the leading
cause of death in children younger than the age of 5 years. While the introduction of the Measles, Mumps, and Rubella vaccine (MMR) has significantly decreased morbidity and mortality rates worldwide, vaccine coverage is highly variable across global regions. Current diagnostic methods rely on enzyme immunoassays (EIA) to detect IgM or IgG Abs in serum. Commercially available Diamedix Immunosimplicity® Measles IgG test kit has been shown to have 91.1% sensitivity and 93.8% specificity, with a positive predictive value of 88.7% and a negative predictive value of 90.9% on the basis of a PRN titer of 120. There is an increasing need for rapid screening for measles specific immunity in outbreak settings. This study aims to develop a rapid molecular diagnostic assay to detect IgG reactive to three individual measles virus (MeV) proteins.
Measles virus (MeV) genes were subcloned into the pJFT7_nGST vector to generate N- terminal GST fusion proteins. Single MeV cistrons were expressed using in vitro transcription/translation (IVTT) with human cell lysate. Expression of GST-tagged proteins was measured with mouse anti-GST mAb and sheep anti-mouse IgG. Relative light units (RLUs) as luminescence was measured. Antibodies to MeV antigens were measured in 40 serum samples from healthy subjects.
Protein expression of three MeV genes of interest was measured in comparison with vector control and statistical significance was determined using the Student’s t-test (p<0.05). N expressed at the highest level with an average RLU value of 3.01 x 109 (p<0.001) and all proteins were expressed at least 50% greater than vector control (4.56 x 106 RLU). 36/40 serum samples had IgG to N (Ag:GST ratio>1.21), F (Ag:GST ratio>1.92), or H (Ag:GST ratio> 1.23).
These data indicate that the in vitro expression of MeV antigens, N, F, and H, were markedly improved by subcloning into pJFT7_nGST vector to generate N-terminal GST fusion proteins. The expression of single MeV genes N, F and H, are suitable antigens for serologic capture analysis of measles-specific antibodies. These preliminary data can be used to design a more intensive study to explore the possibilities of using these MeV antigens as a diagnostic marker.
cause of death in children younger than the age of 5 years. While the introduction of the Measles, Mumps, and Rubella vaccine (MMR) has significantly decreased morbidity and mortality rates worldwide, vaccine coverage is highly variable across global regions. Current diagnostic methods rely on enzyme immunoassays (EIA) to detect IgM or IgG Abs in serum. Commercially available Diamedix Immunosimplicity® Measles IgG test kit has been shown to have 91.1% sensitivity and 93.8% specificity, with a positive predictive value of 88.7% and a negative predictive value of 90.9% on the basis of a PRN titer of 120. There is an increasing need for rapid screening for measles specific immunity in outbreak settings. This study aims to develop a rapid molecular diagnostic assay to detect IgG reactive to three individual measles virus (MeV) proteins.
Measles virus (MeV) genes were subcloned into the pJFT7_nGST vector to generate N- terminal GST fusion proteins. Single MeV cistrons were expressed using in vitro transcription/translation (IVTT) with human cell lysate. Expression of GST-tagged proteins was measured with mouse anti-GST mAb and sheep anti-mouse IgG. Relative light units (RLUs) as luminescence was measured. Antibodies to MeV antigens were measured in 40 serum samples from healthy subjects.
Protein expression of three MeV genes of interest was measured in comparison with vector control and statistical significance was determined using the Student’s t-test (p<0.05). N expressed at the highest level with an average RLU value of 3.01 x 109 (p<0.001) and all proteins were expressed at least 50% greater than vector control (4.56 x 106 RLU). 36/40 serum samples had IgG to N (Ag:GST ratio>1.21), F (Ag:GST ratio>1.92), or H (Ag:GST ratio> 1.23).
These data indicate that the in vitro expression of MeV antigens, N, F, and H, were markedly improved by subcloning into pJFT7_nGST vector to generate N-terminal GST fusion proteins. The expression of single MeV genes N, F and H, are suitable antigens for serologic capture analysis of measles-specific antibodies. These preliminary data can be used to design a more intensive study to explore the possibilities of using these MeV antigens as a diagnostic marker.
ContributorsMushtaq, Zuena (Author) / Anderson, Karen (Thesis advisor) / Blattman, Joseph (Committee member) / Lake, Douglas (Committee member) / Arizona State University (Publisher)
Created2016
Description
The majority of non-small cell lung cancer (NSCLC) patients (70%) are diagnosed with adenocarcinoma versus other histological subtypes. These patients often present with advanced, metastatic disease and frequently relapse after treatment. The tumor suppressor, Liver Kinase B1, is frequently inactivated in adenocarcinomas and loss of function is associated with a highly aggressive, metastatic tumor (1). Identification of the mechanisms deregulated with LKB1 inactivation could yield targeted therapeutic options for adenocarcinoma patients. Re-purposing the immune system to support tumor growth and aid in metastasis has been shown to be a feature in cancer progression (2). Tumor associated macrophages (TAMs) differentiate from monocytes, which are recruited to the tumor microenvironment via secretion of chemotaxic factors by cancer cells. We find that NSCLC cells deficient in LKB1 display increased secretion of C-C motif ligand 2 (CCL2), a chemokine involved in monocyte recruitment. To elucidate the molecular pathway regulating CCL2 up-regulation, we investigated inhibitors of substrates downstream of LKB1 signaling in A549, H23, H2030 and H838 cell lines. Noticeably, BAY-11-7082 (NF-κB inhibitor) reduced CCL2 secretion by an average 92%. We further demonstrate that a CCR2 antagonist and neutralizing CCL2 antibody substantially reduce monocyte migration to NSCLC (H23) cell line conditioned media. Using an in vivo model of NSCLC, we find that LKB1 deleted tumors demonstrate a discernible increase in CCL2 levels compared to normal lung. Moreover, tumors display an increase in the M2:M1 macrophage ratio and increase in tumor associated neutrophil (TAN) infiltrate compared to normal lung. This M2 shift was significantly reduced in mice treated with anti-CCL2 or a CCR2 antagonist and the TAN infiltrate was significantly reduced with the CCR2 antagonist. These data suggest that deregulation of the CCL2/CCR2 signaling axis could play a role in cancer progression in LKB1 deficient tumors.
ContributorsFriel, Jacqueline (Author) / Inge, Landon (Thesis advisor) / Lake, Douglas (Thesis advisor) / Blattman, Joseph (Committee member) / Arizona State University (Publisher)
Created2015