TLR4 adjuvanted vaccine against Pseudomonas aeruginosa virulence factor, Pf bacteriophage, induces increased immunoglobulin response and highly mutated antigen-specific B-cell receptors

Author

Valery Cristina Roman-Cruz

Year of Award

2023

Document Type

Dissertation

Degree Type

Doctor of Philosophy (PhD)

Degree Name

Cellular, Molecular and Microbial Biology

Department or School/College

Department of Biomedical and Pharmaceutical Sciences

Committee Chair

Jay Evans

Commitee Members

Patrick Secor, Mike Minnick, Scott Wetzel, Dave Shepherd, Celine Beamer

Keywords

Adjuvants, B-cell, Pf Bacteriophage, Pseudomonas aeruginosa, Vaccines

Abstract

Pseudomonas aeruginosa is listed as a priority 1 pathogen by the World Health Organization. Although this Gram-negative bacterium is ubiquitous and can naturally be found in the environment, it is opportunistic. P. aeruginosa has a wide range of host immune evasion strategies; one such strategy is the establishment of biofilms. Pf bacteriophage, a P. aeruginosa virulence factor, can strengthen the integrity of biofilms and can also misdirect the host immune response from an appropriate anti-bacterial response to an anti-viral response. Previous studies have established that antibodies against Pf bacteriophage can enhance clearance of P. aeruginosa infections. Next generation adjuvants such as TLR adjuvants have the ability to increase the magnitude of antigen-specific antibodies and generate a lasting immune response against pathogens. In this dissertation, we hypothesized incorporation of a TLR4 agonist will result in an enhanced immune response against the Pf bacteriophage. Herein, we demonstrate antibodies generated from the optimized vaccine are functional and able to recognize Pf virions and disrupt phage replication cycle. Additionally, we have optimized a Pf-bacteriophage-adjuvanted vaccine which incorporates antigen from two distinct clades and optimized a Pf-bacteriophage-adjuvanted vaccine for intranasal administration. Vaccination lead to mucosal immune response and broadened antibody response. Furthermore, after isolating antigen-specific B-cells we used single-cell sequencing techniques to explore the adjuvant effects on the humoral response. We discovered adjuvants affect clonality and heavy chain mutation accumulation in antigen specific B-cell population.

Recommended Citation

Roman-Cruz, Valery Cristina, "TLR4 adjuvanted vaccine against Pseudomonas aeruginosa virulence factor, Pf bacteriophage, induces increased immunoglobulin response and highly mutated antigen-specific B-cell receptors" (2023). Graduate Student Theses, Dissertations, & Professional Papers. 12203.
https://scholarworks.umt.edu/etd/12203