Проблемы особо опасных инфекций (Jul 2021)

Comparative Analysis of the Immunogenic Activity of the Plague Vaccine Depending on the Growing Medium

  • S. E. Gostishcheva,
  • N. V. Abzaeva,
  • E. L. Rakitina,
  • D. G. Ponomarenko,
  • M. V. Kostyuchenko,
  • L. S. Katunina,
  • O. V. Logvinenko,
  • G. F. Ivanova,
  • A. A. Kurilova

DOI
https://doi.org/10.21055/0370-1069-2021-2-148-151
Journal volume & issue
Vol. 0, no. 2
pp. 148 – 151

Abstract

Read online

The aim was to carry out a comparative analysis of the immunogenic activity of the live plague vaccine obtained on various nutrient media.Materials and methods. The subject of the study was the blood of outbred white mice immunized with a series of live plague vaccine based on Yersinia pestis EV NIIEG strain, produced using experimental and regulated nutrient media. The immunogenic activity of vaccines was studied through flow cytometry. The intensity of antigen-reactivity of lymphocytes was determined in cell tests in vitro, analyzing the early activation marker CD25+ . For the specific activation of lymphocytes, a complex of water-soluble antigens of the plague microbe was used. To identify the interdependence between the presence of protective anti-plague immunity and the level of CD 25+ expression intensity, the ED50 of the series under study was determined by the standard method.Results and discussion. A comparative analysis of the immunogenic activity of the live plague vaccine obtained on the experimental nutrient medium with the vaccine produced on Hottinger’s agar has been performed. When animals were immunized with doses of 4·103 , 2·104 and 1·105 live microbial cells (regulated doses), the highest level of expression of CD25 marker by lymphocytes was on the day 14, with a subsequent decrease on the day 21 after vaccination. When determining immunogenicity using the conventional method, a high degree of direct correlation between the number of surviving animals and an increase in the level of lymphocytes expressing markers of early activation has been established. Comparison has revealed the general pattern: when the lowest immunizing dose (8·102 ) was administered, activation of early immunity markers was not observed. In case of immunization with higher doses on days 7, 14 and 21, a proportional increase in the number of CD25-positive lymphocytes after stimulation with a specific antigen under in vitro conditions is detected in the blood of biomodels.

Keywords