The University of Georgia
College of Veterinary Medicine
Class of 2021
Development of novel vaccines and immunological reagents for pathogenic Brucella species
Victoria R. Trutwin, Eric R. Lafontaine, and Jeremy S. Dyke
Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia
Highly pathogenic Brucella species include B. melitensis, B. abortus, and B. suis. These organisms cause brucellosis, the most common zoonotic disease in the world. Currently, no vaccine exists for humans and licensed veterinary live attenuated Brucella vaccine strains provide incomplete protection, interfere with diagnostic tests, and are pathogenic to humans. Our ultimate goal is to develop safe and cross-protective vaccinations for humans and animals against brucellosis. To accomplish this, we are developing a novel vaccine platform using a viral vector delivery system expressing Brucella high value target antigens BatE, BatF, and Omp25. BatE and BatF are autotransporter proteins involved in host colonization, while Omp25 is an outer membrane protein previously shown to provide protection in subunit vaccines. The goal of this project is to develop immunological reagents to validate viral constructs expressing Brucella vaccine targets and immune responses evoked by vaccination with these constructs. To achieve this, gene fragments encoding BatE, BatF, and Omp25 proteins were cloned in the expression plasmid vector pETcoco-1, which specifies an N-terminal His-tag for affinity purification. Recombinant proteins were overexpressed in E. coli, purified under denaturing conditions, refolded, and used to generate murine antibodies (polyclonal and monoclonal) specific for BatE, BatF, and Omp25. These antibodies will be used to verify expression of the vaccine targets by the viral vector delivery system and to study expression of these high value antigens by Brucella species during infection. Recombinant proteins will also be used as reagents to study immune responses elicited by vaccines (e.g. antigen recall assay, ELISA).
Research Grant: GALVmed-AgResults Brucellosis Prize awarded to ERL.
Student Support: NIH Office of Research Infrastructure Programs, Grant Number 5T35OD010433-12