Protective Activity of Inactivated Rabies Vaccine Using Flagellin-Based Adjuvant

Rabies is a zoonotic disease with a high degree of lethality. Most human deaths are related to bites received from dogs and cats. Vaccination is the most effective method of preventing rabies disease in both animals and humans. In this study, the ability of an adjuvant based on recombinant Salmonella typhimurium flagellin to increase the protective activity of an inactivated rabies vaccine in mice was evaluated. A series of inactivated dry culture vaccine for dogs and cats “Rabikan” (strain “Shchelkovo-51”) with the addition of an adjuvant in various dilutions were used. The control preparation was a similar series of inactivated dry culture vaccine without an adjuvant. The protective activity of vaccine preparations was evaluated by the NIH potency test, which is the most widely used and internationally recommended method of determining the effectiveness for testing inactivated rabies vaccines. The value of the specific activity of the tested rabies vaccine when co-administered with an adjuvant was significantly higher (48.69 IU/ml) than that of the vaccine without an adjuvant (3.75 IU/ml). Thus, recombinant flagellin can be considered as an effective adjuvant in the composition of future vaccine preparations against rabies virus.