Specific T-Cell Immune Response to SARS-CoV-2 Spike Protein over Time in Naïve and SARS-CoV-2 Previously Infected Subjects Vaccinated with BTN162b2

Abstract

Due to the COVID-19 pandemic, the rapid development of vaccines against SARS-CoV-2 has been promoted. BNT162b2 is a lipid-nanoparticle mRNA vaccine with 95% efficacy and is the most administered vaccine globally. Nevertheless, little is known about the cellular immune response triggered by vaccination and the immune behavior over time. Therefore, we evaluated the T-cell immune response against the SARS-CoV-2 spike protein and neutralization antibodies (nAbs) in naïve and SARS-CoV-2 previously infected subjects vaccinated with BTN162b2. Methods: Forty-six BTN162b2 vaccinated subjects were included (twenty-six naïve and twenty SARS-CoV-2 previously infected subjects vaccinated with BTN162b2). Blood samples were obtained at basal (before vaccination), 15 days after the first dose, and 15 days after the second dose, to evaluate cellular immune response upon PBMC’s stimulation and cytokine levels. The nAbs were determined one and six months after the second dose. Results: SARS-CoV-2 previously infected subjects vaccinated with BTN162b2 showed the highest proportion of nAbs compared to naïve individuals one month after the second dose. However, women were more prone to lose nAbs percentages over time significantly. Furthermore, a diminished CD154+ IFN-γ+ CD4+ T-cell response was observed after the second BTN162b2 dose in those with previous SARS-CoV-2 infection. In contrast, naïve participants showed an overall increased CD8+ IFN-γ+ TNF-α+ T-cell response to the peptide stimulus. Moreover, a significant reduction in IP-10, IFN-λI, and IL-10 cytokine levels was found in both studied groups. Additionally, the median fluorescence intensity (MFI) levels of IL-6, IFNλ-2/3, IFN-𝛽, and GM-CSF (p < 0.05) were significantly reduced over time in the naïve participants. Conclusion: We demonstrate that a previous SARS-CoV-2 infection can also impact cellular T-cell response, nAbs production, and serum cytokine concentration. Therefore, the study of T-cell immune response is essential for vaccination scheme recommendations; future vaccine boost should be carefully addressed as continued stimulation by vaccination might impact the T-cell response.

IL-2-mediated CD4 T-cell activation correlates highly with effective serological and T-cell responses to SARS-CoV-2 vaccination in people living with HIV (PLWH)

“…We therefore addressed intracellular expressions of TNF-α, IFN-γ, and, IL-2 in CD4 + and CD8 + T-cells in PLWH population and compared them to controls ( Figure 4A, B ). While the cytokine expression of S-specific IL-2, TNF-α, and IFN-γ in CD4 + T-cells did not significantly change during the study period, a declining trend was observed by T3 (Table 2), as observed earlier 29 . CD4 + or CD8 + T-cells co-expressing IFN-γ + TNF-α + IL-2 + were much more frequent in controls, however, did not reach statistical significance with either of the PLWH groups.…”

Cytokine levels in maternal and infant blood after COVID-19 vaccination during pregnancy in comparison with unvaccinated controls

“…( Ndeupen et al, 2021 ) Previous studies have demonstrated a cytokine response of an increase in IP-10 and IFN-γ levels immediately after COVID-19 vaccination ( Bergamaschi et al, 2021 ). Other studies, however, found a reduction in IP-10, IFN-λ1, and IL-10 cytokine levels after vaccination against COVID-19 ( Vega-Magaña et al, 2022 ).…”

BNT162b2 Vaccination after SARS-CoV-2 Infection Changes the Dynamics of Total and Neutralizing Antibodies against SARS-CoV-2: A 6-Month Prospective Cohort Study

“…Therefore, on average, studies report a preference for the female gender to produce greater antibody responses and higher B cell activity compared to men [ 23 , 42 , 43 ]. However, other authors have determined that gender does not affect the production of antibodies induced by natural infection or vaccination [ 44 , 45 ]. Numerous factors can influence immune function, including age, underlying health conditions, and lifestyle; therefore, more studies are needed in this regard, especially in larger cohorts.…”