Researchers conducted a prospective study to assess the effectiveness of additional vaccine boosters in patients who received the initial SARS-CoV-2 vaccination series within the first year of the pandemic.
They assessed the temporal profile of cellular and serological responses in 639 individuals who received the SARS-CoV-2 vaccine. A significant portion of these individuals experienced a SARS-CoV-2 infection. At the time of their first vaccine dose, all participants were infection-free. The activation-induced Markers (AIM) assay was used to measure the proportions of SARS-CoV-2 Spike-specific T cells after each vaccine dose. Additionally, levels of circulating SARS-CoV-2 antibodies were determined through the Meso Scale serology assay.
The results showed a notable rise in SARS-CoV-2 Spike-specific CD4+ and CD8+ T cell reactions after the third dose of an mRNA vaccine against SARS-CoV-2 and improved CD8+ T cell responses post-fourth dose—moreover, older age correlated with a diminished response. Lastly, SARS-CoV-2 infection amplified cellular and humoral immune responses compared to vaccination alone.
Investigators concluded that repeated vaccinations enhanced T cell immunity, with both vaccination and natural infection contributing to maintaining population T cell levels, though these levels waned in older adults.
Fair Use Notice
UNMC Global Center for Health Security staff curate publicly available news and information for educational and informational purposes. Brief excerpts of published articles may be displayed under principles of Fair Use, with credit and links provided to the source publications. All copyrights remain the property of their respective owners.