This escape potential also explains why the number of breakthrough infections in vaccinated individuals has increased significantly since the occurrence of the omicron subvariants: Due to the numerous mutations in the spike protein, many of the antibodies induced by vaccination and/or infection cannot bind to the mutated spike protein and thus do not develop their neutralizing potential.Ĭlinical study shows non-omicron adapted COVID-19 vaccines don't provide continued high antibody levels against omicron variantsĪ research team at the Paul-Ehrlich-Institut led by Professor Eberhard Hildt, head of the Virology Division, investigated the influence of the original mRNA vaccines Comirnaty (BioNTech) and Spikevax (Moderna), which had not yet been adapted to the omicron variants, on the levels of protection against omicron variants offered by neutralizing antibodies in a clinical study.Īfter primary immunization (Comirnaty), the subjects had low blood levels (titers) of neutralizing antibodies to omicron. As a result, the corresponding virus variants evade the immune response. The omicron subvariants have an enormous escape potential due to the destruction or deletion of different areas of the virus that are important for the immune response (epitopes). Omicron subvariants of the SARS-CoV-2 coronavirus have dominated since the beginning of 2022. SARS-CoV-2 omicron variants necessitate vaccine adaptations Booster vaccination also stimulates a broader humoral immune response, which is produced by differentiation processes of the antibody genes (somatic hypermutation) and antibody affinity maturation. This baseline level is built up or refreshed by the immunological memory, resulting in an increase in memory B cells and long-lived plasma cells, which in turn form antibodies.īoth cell types are important pillars of the antibody-based humoral immune response. The antibody titer then drops to a baseline level after the first few months. Boosters are administered for several reasons: antibody titers rise rapidly within the first two weeks after a booster vaccination and offer the best protection against COVID-19. The research is published in the journal Scientific Reports.īooster vaccination to strengthen immunological memoryīooster shots are recommended in most age groups to protect against COVID-19. These are the results of a clinical study conducted by the Paul-Ehrlich-Institut in vaccinated health care professionals. The fourth vaccination also had no effect on the breadth of the immune response against different virus variants.Įven with primary immunization with Comirnaty, only small amounts of neutralizing antibodies against omicron were present. However, these antibody titers drop significantly six months after the third or fourth vaccination. p values are based on the Kruskal–Wallis test with FDR correction: > 0.0331 (ns) 0.0331 (*) 0.0021 (**) 0.0002 (***) < 0.0001 (****).īooster vaccinations (third and fourth vaccinations) of COVID-19 mRNA vaccines that are not adapted to omicron variants do lead to higher blood levels of neutralizing antibodies against the omicron subvariants. (C) Antibody response against the omicron variant of SARS-CoV-2. (B) Antibody response against the delta variant of SARS-CoV-2. (A) Antibody response against the original Wuhan-Hu1 SARS-CoV-2. The median with interquartile range is shown for each time point. Anti-SARS-CoV-2 RBD IgG and IgA antibody levels against different SARS-CoV-2 variants at 6 months after third vaccination (6m3V), 2 weeks after fourth vaccination (2w4V) and 6 months after fourth vaccination (6m4V). IgG and IgA antibody responses of vaccinated individuals.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |