Date of Award

Fall 2023

Document Type


Degree Name

Master of Science (MS)


Biological Sciences



Committee Director

Lisa M. Shollenberger

Committee Member

Wayne Hynes

Committee Member

Erin Purcell


Vaccination is one of the most effective strategies employed to prevent infectious diseases. Successful vaccination is dependent upon the induction of a specific, robust, and prolonged immune response. One of the major challenges faced by vaccine development is vaccine failure due to host-related factors that can modulate the immune system, which leads to non-responsiveness to vaccinations. The generation of new vaccine strategies is imperative to combat these effects. Live bacterial vectors are one approach used as they can elicit humoral immunity, cellular immunity, or both. Listeria monocytogenes is a Gram positive, intracellular pathogen that is an effective bacterial vaccine vector through strong induction of cell-mediated immunity. Specifically, wild-type Listeria expressing the HIV-Gag protein was previously shown to be a functional vector in overcoming host-related immune bias when DNA vaccines alone could not. However, there are safety concerns due to its pathogenicity and therefore new clinically relevant vectors with attenuated Listeria strains are needed. Here, a comparison of the pathogenicity (LD50) is determined for several Listeria strains. Additionally, the HIV-Gag protein has been cloned into the pKSV7 shuttle vector for future use in attenuated Listeria strains. Our aim is that these non-pathogenic vectors will be clinically relevant for use in overcoming Th1/Tc1 type vaccine failure.


In Copyright. URI: This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).