Медицинская иммунология (Aug 2019)

DETERMINATION OF THE T-CELL IMMUNE RESPONSE TO THE SARS-COV-2 CORONAVIRUS BASED ON THE INDUCTION OF Γ-INTERFERON PRODUCTION BY SPECIFIC PERIPHERAL BLOOD T-LYMPHOCYTES WHEN STIMULATED BY A VIRAL ANTIGEN

  • Bogdan Sergeevich Cherepovich,
  • Alexandra Mikhailovna Kudryashova,
  • Lyudmila Leonidovna Pankratieva,
  • Bogolyubova Vasilyevna Bogolyubova,
  • Victor Alexandrovich Manuilov,
  • Vladimir Alekseevich Gushchin,
  • Andrey Andreevich Pochtovyi,
  • Olga Vasilyevna Borisova,
  • Oksana Anatolyevna Svitich

DOI
https://doi.org/10.15789/1563-0625-DOT-3007
Journal volume & issue
Vol. 0, no. 0

Abstract

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The aim of this work was to study the ability of T cells immune to SARS-CoV-2 in humans to produce γ-IFN, which is one of the markers of T-cell immunity, in response to stimulation by a peptide pool in whole blood. Materials and methods. 80 whole blood samples were examined volunteers with a known medical history received in 2021 and 258 volunteers received in September-October 2022. In this study, 2 methods were used - 1) solid-phase enzyme immunoassay to determine antibodies of class G to RBD SARS-CoV-2, 2) IGRA test to determine γ-IFN produced by antigen-specific lymphocytes in response to their stimulation by viral antigen. Results. The parameters of the IGRA test were optimized on a sample of 80 samples of volunteers. The threshold value of the level of γ-IFN (4.85 pg/ml) was determined, diagnostic specificity -100% (80.6-100); diagnostic sensitivity -92,19% (83-96,6%), 95% CI.Then a study was conducted on a sample of 258 volunteers, 28.7% of whom, according to the results of the IGRA test, did not exceed the threshold level of γ-IFN after stimulation, while all volunteers had class G antibodies to RBB SARS-CoV-2. There was no correlation between the level of antibodies and the level of interferon response in the entire group. When comparing IgG antibody levels and the amplitude of IFN-γ exceeding the baseline level in the sample groups differing in the time of the last vaccination, the median values of the parameters were slightly higher for the part of the sample that underwent revaccination 1-2 months before the study, while a significant difference between the two samples was revealed only when evaluating γ-IFN, pg/ml (Mann-Whitney criterion, p=0.0321).Conclusion. According to the results of the study, it can be assumed that all the patients in the sample who were vaccinated and had COVID-19 infection had humoral immunity, but about a third of them lacked cellular immunity to SARS-CoV-2. There was no correlation between the level of antibodies and the level of interferon response (Spearman's criterion). It was shown that revaccination in the previous 1-2 months contributed to an increase in the amplitude of the interferon response.

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