Recombinant Escherichia coli derived outer membrane vesicles for safe and effective subunit antigen delivery

Hannah Christine Watkins
Subunit vaccines rely on adjuvants to drive an immune response against antigens of interest. Improved adjuvant platforms, capable of interaction with specific pathogen recognition receptors in the innate immune system, can lead to more effective and longer lasting vaccines. Recombinant outer membrane vesicles (rOMVs) are a recently developed adjuvant system that harnesses the natural pathogen associated molecular patterns present in the outer membrane of E. coli to direct an immune response
more » ... nst recombinant antigens displayed on the rOMV surface. Though rOMV vaccines have demonstrated promise against viral antigens in murine models, their high lipopolysaccharide (LPS) content hinders translation to humans. This dissertation will present ways in which the LPS in rOMVs can be modified, through use of 'detoxified' commercial E. coli strains, as well as through genetic manipulation of probiotic E. coli strains, to generate rOMVs with greatly improved safety profiles. Additionally, it will profile the development of a potential pandemic influenza vaccine using detoxified rOMVs, demonstrating their feasibility in achieving protective immune responses. iv BIOGRAPHICAL SKETCH Hannah was born on April 17 th , 1989 in Dumas, Texas. After nine too many years in Texas, she moved to Kenai, Alaska in 1998. She graduated from the University of Rochester in May 2011, with a B.S. in Biomedical Engineering and minors in Chemical Engineering and Biology. While at Rochester, Hannah conducted research under Danielle Benoit in polymer systems for targeted drug delivery. Hannah then spent 14 months at Imperial College London on Whitaker and Fulbright Fellowships, working under Professor Molly Stevens on assay development using gold nanostars. Hannah received an M.Phil in Materials Engineering from Imperial College London in Aug. 2013. Hannah started her PhD in Biomedical Engineering at Cornell in fall 2012, with the support of a National Science Foundation Graduate Research Fellowship. At Cornell, she worked under the guidance of David Putnam to develop outer membrane vesicles as a safe and effective adjuvant platform. v 'OMG! OMV!' -anonymous vi ACKNOWLEDGMENTS First, thank you to my advisor, David Putnam. Thank you, Dave, for the support and enthusiasm you have provided over the past four and a half years. Thanks for always asking 'What can I do to help?', connecting me to others in the field, giving me freedom to design my own project, and providing me with many cookies. I am lucky to have had an advisor who supports work-life balance as much as you do. Thank you also to my minor committee members: Gary Whittaker and Matthew DeLisa. Thank you, Gary, for welcoming me into your lab (and lab meetings and lab outings) and for providing valuable insight about influenza. Thank you, Matt, for suggesting the Clearcoli project and for giving me freedom to take it in my own direction. Though not an official committee member, this work would not have been possible without the assistance and guidance of Cynthia Leifer. Thank you, Cindy, for sharing your wealth of immunology knowledge, helping to troubleshoot experiments, and providing me with resources for studying the interactions of rOMVs with the innate immune system. The Putnam Lab is a pretty special place and I have had the privilege of working with many interesting people throughout the years. Thank you to the following PhD students for helping to make the Putnam Lab a warm and welcoming environment: Jen, who introduced me to the Ithaca Concert Band; Joseph, who patiently trained me in rOMV techniques, gave me project guidance, and knew all the answers to all the questions; Mingchee, for being a bouldering buddy; Lindsey, who brightened my mornings with dancing and singing; Jose, the best post-doc undergrad ever; Nicole, my go-to person for all professional advice and an amazingly skilled email crafter; Bailey, who even when overloaded with work still helped others and left emergency chocolate under desks; Zhexun, for answering chemistry questions and translating labels; Sarah, for her tree knowledge and informative signs, and finally, Dave, for taking over the rOMV characterized ..
doi:10.7298/x46h4ff1 fatcat:u6zh3gb7b5anjfztf2rh36vx7u