Scholarly Work - Plant Sciences & Plant Pathology
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/8870
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Item Virus-like Particle-Induced Protection against MRSA Pneumonia Is Dependent on IL-13 and Enhancement of Phagocyte Function(2012-07) Rynda-Apple, Agnieszka; Dobrinen, Erin; McAlpine, Mark; Read, Amanda; Harmsen, Ann L.; Richert, Laura E.; Calverley, Matthew; Pallister, Kyler; Voyich, Jovanka M.; Wiley, James A.; Johnson, Ben; Young, Mark J.; Douglas, Trevor; Harmsen, Allen G.The importance of the priming of the lung environment by past infections is being increasingly recognized. Exposure to any given antigen can either improve or worsen the outcome of subsequent lung infections, depending on the immunological history of the host. Thus, an ability to impart transient alterations in the lung environment in anticipation of future insult could provide an important novel therapy for emerging infectious diseases. In this study, we show that nasal administration of virus-like particles (VLPs) before, or immediately after, lethal challenge with methicillin-resistant Staphylococcus aureus (MRSA) of mice i) ensures complete recovery from lung infection and near absolute clearance of bacteria within 12 hours of challenge, ii) reduces host response-induced lung tissue damage, iii) promotes recruitment and efficient bacterial clearance by neutrophils and CD11c+ cells, and iv) protects macrophages from MRSA-induced necrosis. VLP-mediated protection against MRSA relied on innate immunity. Complete recovery occurred in VLP-dosed mice with severe combined immunodeficiency, but not in wild-type mice depleted of either Ly6G+ or CD11c+ cells. Early IL-13 production associated with VLP-induced CD11c+ cells was essential for VLP-induced protection. These results indicate that VLP-induced alteration of the lung environment protects the host from lethal MRSA pneumonia by enhancing phagocyte recruitment and killing and by reducing inflammation-induced tissue damage via IL-13–dependent mechanisms.Item Inducible bronchus-associated lymphoid tissue elicited by a protein cage nanoparticle enhances protection in mice against diverse respiratory viruses(2009-09) Wiley, James A.; Richert, Laura E.; Swain, Steve D.; Harmsen, Ann L.; Barnard, Dale L.; Randall, Troy D.; Jutila, Mark A.; Douglas, Trevor; Broomell, Chris; Young, Mark J.; Harmsen, Allen G.Background Destruction of the architectural and subsequently the functional integrity of the lung following pulmonary viral infections is attributable to both the extent of pathogen replication and to the host-generated inflammation associated with the recruitment of immune responses. The presence of antigenically disparate pulmonary viruses and the emergence of novel viruses assures the recurrence of lung damage with infection and resolution of each primary viral infection. Thus, there is a need to develop safe broad spectrum immunoprophylactic strategies capable of enhancing protective immune responses in the lung but which limits immune-mediated lung damage. The immunoprophylactic strategy described here utilizes a protein cage nanoparticle (PCN) to significantly accelerate clearance of diverse respiratory viruses after primary infection and also results in a host immune response that causes less lung damage. Methodology/Principal Findings Mice pre-treated with PCN, independent of any specific viral antigens, were protected against both sub-lethal and lethal doses of two different influenza viruses, a mouse-adapted SARS-coronavirus, or mouse pneumovirus. Treatment with PCN significantly increased survival and was marked by enhanced viral clearance, accelerated induction of viral-specific antibody production, and significant decreases in morbidity and lung damage. The enhanced protection appears to be dependent upon the prior development of inducible bronchus-associated lymphoid tissue (iBALT) in the lung in response to the PCN treatment and to be mediated through CD4+ T cell and B cell dependent mechanisms. Conclusions/Significance The immunoprophylactic strategy described utilizes an infection-independent induction of naturally occurring iBALT prior to infection by a pulmonary viral pathogen. This strategy non-specifically enhances primary immunity to respiratory viruses and is not restricted by the antigen specificities inherent in typical vaccination strategies. PCN treatment is asymptomatic in its application and importantly, ameliorates the damaging inflammation normally associated with the recruitment of immune responses into the lung.Item Something old, something new, something borrowed; how the thermoacidophilic archaeon Sulfolobus solfataricus responds to oxidative stress(2009-09) Maaty, Walid S.; Wiedenheft, Blake A.; Tarlykov, Pavel V.; Schaff, Nathan; Heinemann, Joshua V.; Robison-Cox, James; Dougherty, Amanda; Blum, Paul; Lawrence, C. Martin; Douglas, Trevor; Young, Mark J.; Bothner, BrianTo avoid molecular damage of biomolecules due to oxidation, all cells have evolved constitutive and responsive systems to mitigate and repair chemical modifications. Archaea have adapted to some of the most extreme environments known to support life, including highly oxidizing conditions. However, in comparison to bacteria and eukaryotes, relatively little is known about the biology and biochemistry of archaea in response to changing conditions and repair of oxidative damage. In this study transcriptome, proteome, and chemical reactivity analyses of hydrogen peroxide (H2O2) induced oxidative stress in Sulfolobus solfataricus (P2) were conducted. Microarray analysis of mRNA expression showed that 102 transcripts were regulated by at least 1.5 fold, 30 minutes after exposure to 30 µM H2O2. Parallel proteomic analyses using two-dimensional differential gel electrophoresis (2D-DIGE), monitored more than 800 proteins 30 and 105 minutes after exposure and found that 18 had significant changes in abundance. A recently characterized ferritin-like antioxidant protein, DPSL, was the most highly regulated species of mRNA and protein, in addition to being post-translationally modified. As expected, a number of antioxidant related mRNAs and proteins were differentially regulated. Three of these, DPSL, superoxide dismutase, and peroxiredoxin were shown to interact and likely form a novel supramolecular complex for mitigating oxidative damage. A scheme for the ability of this complex to perform multi-step reactions is presented. Despite the central role played by DPSL, cells maintained a lower level of protection after disruption of the dpsl gene, indicating a level of redundancy in the oxidative stress pathways of S. solfataricus. This work provides the first “omics” scale assessment of the oxidative stress response for an archeal organism and together with a network analysis using data from previous studies on bacteria and eukaryotes reveals evolutionarily conserved pathways where complex and overlapping defense mechanisms protect against oxygen toxicity.Item Melanoma and Lymphocyte Cell Specific Targeting Incorporated into a Heat Shock Protein Cage Architecture(2006) Flenniken, Michelle L.; Willits, Deborah A.; Harmsen, Ann L.; Liepold, Lars O.; Harmsen, Allen G.; Young, Mark J.; Douglas, TrevorProtein cages, including viral capsids, ferritins, and heat shock proteins (Hsps), can serve as nanocontainers for biomedical applications. They are genetically and chemically malleable platforms, with potential as therapeutic and imaging agent delivery systems. Here, both genetic and chemical strategies were used to impart cell-specific targeting to the Hsp cage from Methanococcus jannaschii. A tumor vasculature targeting peptide was incorporated onto the exterior surface of the Hsp cage. This protein cage bound to αvβ3 integrin-expressing cells. Cellular tropism was also imparted by conjugating anti-CD4 antibodies to the exterior of Hsp cages. These Ab-Hsp cage conjugates specifically bound to CD4+ cells. Protein cages have the potential to simultaneously incorporate multiple functionalities, including cell-specific targeting, imaging, and therapeutic agent delivery. We demonstrate the simultaneous incorporation of two functionalities, imaging and cell-specific targeting, onto the Hsp protein cage.Item Microbe manufacturers of semiconductors(2004-11) Flenniken, Michelle L.; Allen, Mark; Douglas, TrevorSynthesis of cadmium sulfide (CdS) semiconductor nanoparticles within a prokaryotic organism is reported for the first time by Sweeney et al. [1]. This paper demonstrates the utility of microorganisms to perform chemistries outside the scope of their “normal” metabolism and offers an environmentally benign synthesis of CdS nanoparticles.Item Biodistribution studies of protein cage nanoparticles demonstrate broad tissue distribution and rapid clearance in vivo(2007-12) Kaiser, Coleen R.; Flenniken, Michelle L.; Gillitzer, Eric; Harmsen, Ann L.; Harmsen, Allen G.; Jutila, Mark A.; Douglas, Trevor; Young, Mark J.Protein cage nanoparticles have the potential to serve as multifunctional cell targeted, imaging and therapeutic platforms for broad applications in medicine. However, before they find applications in medicine, their biocompatibility in vivo needs to be demonstrated. We provide here baseline biodistribution information of two different spherical protein cage nanoplatforms, the 28 nm viral Cowpea chlorotic mottle virus (CCMV) and the 12 nm heat shock protein (Hsp) cage. In naïve and immunized mice both nanoplatforms show similar broad distribution and movement throughout most tissues and organs, rapid excretion, the absence of long term persistence within mice tissue and organs, and no overt toxicity after a single injection. These results suggest that protein cage based nanoparticles may serve as safe, biocompatible, nanoplatforms for applications in medicine.Item Targeted delivery of a photosensitizer to Aggregatibacter actinomycetemcomitans biofilm(2010-04) Suci, Peter A.; Kang, Sebyung; Gmür, Rudolf; Douglas, Trevor; Young, Mark J.The ability to selectively target specific biofilm species with antimicrobials would enable control over biofilm consortium composition, with medical applications in treatment of infections on mucosal surfaces that are colonized by a mixture of beneficial and pathogenic microorganisms. We functionalized a genetically engineered multimeric protein with both a targeting moiety (biotin) and either a fluorophore or a photosensitizer (SnCe6). Biofilm microcolonies of Aggregatibacter actinomycetemcomitans, a periodontal pathogen, were targeted with the multifunctional dodecamer. Streptavidin was used to couple biotinylated dodecamer to a biotinylated anti-A. actinomycetemcomitans antibody. This modular targeting approach enabled us to increase the loading of photosensitizer onto the cells by a cycle of amplification. Scanning laser confocal microscopy was used to characterize transport of fluorescently tagged dodecamer into the microcolonies and targeting of the cells with biotin-labeled, fluorescently tagged dodecamer. Light-induced activity of the targeted photosensitizer reduced the viability of A. actinomycetemcomitans biofilm, as indicated by membrane permeability to propidium iodide. The functionalized multimeric protein promises to be a useful tool for controlling periodontal biofilm consortia and offers a modular design whereby moieties that target different species can be readily combined with the functionalized protein construct.