relation: http://d-scholarship-dev.library.pitt.edu/33923/
title: Using tissue culture to model early events in Francisella tularensis pathogenesis
creator: Burwinkel, Jennifer
description: Francisella tularensis (Ft) is a highly infectious bacterium that causes tularemia, which manifests in multiple presentations such as ulceroglandular, pneumonic, or typhoidal forms. Pneumonic tularemia, a more severe manifestation, can result from inhalation of as few as 10 colony forming units of Ft. The low infectious dose, its potential for aerosolization, and severity of disease has resulted in Ft classification as a Select Agent by the CDC for bioweapon potential. The severe clinical and financial burden a bioweapon attack utilizing Ft would impose on the U.S. makes development of therapeutics and vaccines an important contribution to protecting public health. Determination of vaccine targets requires knowledge of the early pathogenesis of Ft in the lungs. Ft infects a wide variety of cells, including lung macrophages and lung epithelial cells, likely involved in initial infection from aerosol; few have compared the permissivity of infection between these cell types to infection by Ft. We utilized an in vitro infection assay with murine macrophages (J774) and human alveolar epithelial cells (A549), and developed an ex vivo infection assay for 3D-cultured human primary bronchial epithelium (HBE), intended to mimic lung architecture. Early cellular events within SCHU S4 infected rabbit tissue, a model which exhibits clinical disease similar to humans, was assessed for cellular infiltration, changes in lung architecture, and apoptosis. I found that different strains of Ft (SCHU S4, LVS, and U112), grow at similar rates in A549 as J774 after initial infection. Moreover, I have demonstrated that Ft can infect HBE in the 3D culture system. These data suggest that it takes Ft longer to infect the HBE cells than the A549 or J774 cells. This is the first infection assay performed within a 3D HBE culture, to our knowledge. Over the course of the first five days post-exposure there is an increasing amount of inflammation, hemorrhaging and apoptosis in rabbit lung. When taken altogether, these data suggest lung epithelial cells have an underappreciated role in Ft early pathogenesis and dissemination.
date: 2018-06-28
type: University of Pittsburgh ETD
type: PeerReviewed
format: application/pdf
language: en
identifier: http://d-scholarship-dev.library.pitt.edu/33923/1/Burwinkeljl_thesis_April_2018.pdf
identifier:   Burwinkel, Jennifer  (2018) Using tissue culture to model early events in Francisella tularensis pathogenesis.  Master's Thesis, University of Pittsburgh.    (Unpublished)