> *Dissertation Defense Announcement: > To: The George Mason University Community* > > *Tony Pierson > PhD Biosciences Candidate > * > *Date: Thursday April 7, 2011 > Time: 11:30 a.m. > Place: George Mason University > ** Bull Run Hall, Room 249 > Prince William campus <http://www.gmu.edu/resources/visitors/findex.html> > > Dissertation Chair: Dr. Monique van Hoek > Committee members: Dr. Charles L. Bailey, Dr. Calvin Carpenter, Dr. Barney Bishop* > *Title: "Specific and Innate Immunity Against Francisella"* > > The dissertation is on reserve in the Johnson Center Library, Fairfax campus.The doctoral project will not be read at the meeting, but should be read in advance. > > > /**/All members of the George Mason University community are invited > to attend. > > /ABSTRACT:/ > > /Francisella tularensis/ is a highly infectious gram negative > bacterium which causes tularemia. > > /Francisella/ produces outer membrane vesicles (OMVs), which release > many proteins into the extracellular proteome. We successfully > demonstrate that a novel /Francisella/ OMV vaccine delivered > intranasally protects BALB/C mice challenged with up to 100 LD50 of > intranasally delivered /Francisella/. Next we demonstrate that > mutations in the Tol/Pal system in /Francisella/ results in OMV > over-production. This finding may lead to a method of producing larger > amounts of OMVs for future vaccine production. Next, we measured > changes in transcription of well characterized as well as novel human > ? defensin (hBD) genes upon exposure to /Francisella/. We observed > increased induction of transcription of hBDs when compared to the > negative control. To demonstrate translation, we used ELISA and found > that the amount of hBD protein in supernatant from each treatment > group was significantly higher than the negative control. We also > visualized hBD2 colocalized with /Francisella/. Together, these > finding demonstrate that hBDs are stimulated by and associated with > /Francisella/ bacteria as well as their OMVs. Finally, we showed that > hBDs stimulate the production of OMVs /in vitro/. Taken together, this > research establishes that OMVs stimulate the innate as well as > specific immunity in a manner similar to whole bacteria. However, OMVs > are acellular, and as such represent a novel vaccine candidate which > is capable of stimulating both innate and specific immunity. > > ### > > >