417 A CTS Team Approach to Developing an Effective Vaccine for Non-Typhoidal Salmonella

Abstract

OBJECTIVES/GOALS: Non-Typhoidal Salmonella causes over 95 million infections globally each year, and no effective vaccine exists to combat infections in humans. The goal of this study is to determine the immune protection provided by a novel extracellular vesicle (EV)-based vaccine generated using lab-strain Salmonella against wastewater-derived Salmonella. METHODS/STUDY POPULATION: We isolated Non-Typhoidal Salmonella (NTS) from raw influent wastewater samples collected from two wastewater reclamation facilities (WRF) in Gainesville, FL. Whole genome sequencing was performed on each isolate and compared to sequences of clinically-derived isolates in FL during our study period to identify a clinical and subclinical isolate for assessing EV based vaccine protection. Mouse serum and stool samples were collected from a cohort of EV-vaccinated mice. Surrogates of protection against Salmonella used anti-Salmonella IgA in the feces of these mice, and anti-Salmonella IgG in serum of the mice, by using ELISAs coated with whole cell lysate collected from the two wastewater-derived isolates. RESULTS/ANTICIPATED RESULTS: We have previously shown that an EV vaccine provides protection against Salmonella enterica Serovar Typhimurium, the serovar used in the generation of the EV vaccine. We anticipate that the EV vaccine generates additional protection against the community-acquired strains, which will be characterized by increases in fecal IgA and serum IgG against two community Salmonella isolates that is similar to responses against the serovar used to generate the EV vaccine (Typhimurium). DISCUSSION/SIGNIFICANCE: This study will improve the translation of our vaccine studies by demonstrating the efficacy of our novel EV vaccine against circulating Salmonella isolates.