Immunogene properties of prototypes of dna vaccine against rabies
The present study was conducted to study the effect of the administration method and the dose of a DNA vaccine against rabies and the addition of an adjuvant to the induction of a protective humoral immune response in experiments in mice. The dy namics of production of virus neutralising antibodies was detected by titration of immune sera taken on days 14, 21 and 28 after mice immunisation. The content (IU / ml) of virus neutralising antibodies in the serum of immunised mice was determined in a fluorescence focus assay inhibition test (FAVN) by titration against a 70-200 TCiD rabies virus strain CVS-11 according to the procedure recommended by the OIE. The protective level was the antibody titer ≥ 0.50 IU / ml. Protective activity of the prototype DNA vaccine was determined in immunised mice, by intracerebral infestation with a dose of 20 LD50 of the standard rabies virus strain CVS-11 on day 28 after immunisation. The results obtained show that intramuscular injection at an optimal dose of 150 μg and subcutaneous at a dose of 40 μg dNa immunisation induces a strong humoral immune response against experimental rabies in mice. It was found that in mice immunized with plasmid DNA vaccine and TM adjuvant in a ratio of 1: 1 (50%), the serum level of virus neutralizing antibodies was 9.6 IU / ml, which is higher than in mice vaccinated in combination with Adjuvant at any other concentration or received only the plasmid DNA vaccine. The results of the protection test in mice showed that the maximum level of protection of mice from intracerebral infecting with a lethal dose of rabies virus strain CVS-11 - 91-100% - is detected after a single immunisation with a plasmid DNA vaccine with 50% adjuvant. These results confirm the effectiveness of increasing the immunogenic activity of the experimental variants of the prototype DNA vaccine against rabies in combination with TM-adjuvant based on the nanoparticles of triter-pene compounds, and also substantiate the prospects for further clinical studies of the DNA vaccine against rabies.