A 52 Kilodalton Protein Vaccine Candidate for Francisella tularensis
DEFENCE RESEARCH AND DEVELOPMENT SUFFIELD (ALBERTA)
Pagination or Media Count:
For identifying Francisella tularensis vaccine candidates, mice were first vaccinated with Brucella abortus O-polysaccharide OPS vaccine. These animals were then given 10 LDsub 50S of F. tularensis live vaccine strain LVS. Sixty percent 60 of the vaccinated mice survived the multiple lethal dose while all the unvaccinated control mice perished. Sera were collected from these surviving mice and used to probe supernatant and cell lysates of live F. tularensis LVS cultures. Several Francisella tularensis components were identified by this noted antiserum. Mouse serum from mice vaccinated with killed F. tularensis did not identify these components. Of these identified proteins, enzyme digestions and chemical oxidation suggest post-translational modifications for some of the proteins e.g. a 52 kilodalton kDa glycoprotein, a 45 kDa lipoprotein and a 19 kDa nucleoprotein. In low concentrations, the 52 kDa component caused nitrous oxide induction in tissue cultures and in high concentrations it caused cell death. Vaccination with this protein gave mice partial protection 20 survival from 250 LDsub 50 of tularemia given intranasally while the addition of other components may have acted synergistically to give enhanced protection i.e. 100 survival.
- Medicine and Medical Research