Immune Assessment of BNT162b2 m-RNA-Spike Based Vaccine Response in Adults

Abstract

Vaccine efficacy is based on clinical data. Currently, the assessment of immune response after SARS-CoV-2 vaccination is scarce. A total of 52 healthcare workers were immunized with the same lot of BNT162b2 vaccine. The immunological response against the vaccine was tested using a T-specific assay based on the expression of CD25 and CD134 after stimulation with anti-N, -S, and -M specific peptides of SARS-CoV-2. Moreover, IgG anti-S2 and -RBD antibodies were detected using ELISA. Furthermore, the cell subsets involved in the response to the vaccine were measured in peripheral blood by flow cytometry. Humoral-specific responses against the vaccine were detected in 94% and 100% after the first and second doses, respectively. Therefore, anti-S T-specific responses were observed in 57% and 90% of the subjects after the first and second doses of the vaccine, respectively. Thirty days after the second dose, significant increases in T helper 1 memory cells (p < 0.001), peripheral memory T follicular helper (pTFH) cells (p < 0.032), and switched memory (p = 0.005) were observed. This study describes the specific humoral and cellular immune responses after vaccination with the new mRNA-based BNT162b2 vaccine. A mobilization of TFH into the circulation occurs, reflecting a specific activation of the immune system.

High Incidence of SARS-CoV-2 Variant of Concern Breakthrough Infections Despite Residual Humoral and Cellular Immunity Induced by BNT162b2 Vaccination in Healthcare Workers: A Long-Term Follow-Up Study in Belgium

“…Serological findings of this cohort were comparable with those described by other groups that studied serology up to 32 weeks after receiving the BNT162b2 vaccine [44][45][46][47][48][49][50][51][52]. Of note, many of these studies monitored vaccine-induced antibody responses in either patients with multiple pathologies (e.g., multiple sclerosis, hemodialysis) [44][45][46]53,54], SARS-CoV-2 convalescent patients [55][56][57] or between patients receiving one, two or three doses of the BNT162b2 vaccine [57,58].…”

An Evaluation of Serological Tests to Determine Postvaccinal Immunity to SARS-CoV-2 by mRNA Vaccines

“…Anti-RBD IGG S1 antibodies were lost in almost half of the participants at 10 months. These data are consistent with those observed in our and other studies that studied serology up to 32 weeks after receiving mRNA vaccines [36][37][38]. Other studies have reported the clinical performance of the Abbott trial [31,35,39] with results similar to ours.…”

COVID-19 mRNA Based Vaccine Immune-Response Assessment in Nursing Home Residents for Public Health Decision

“…The specific cellular immune response against vaccination was assessed as previously described [13]. Briefly, peripheral blood mononuclear cells (PBMCs) from sodiumheparinized blood were isolated by Ficoll gradient and cultured at 10 6 /mL in TexMACS medium (MiltenyiBiotec, BergischGladbach, Germany) during 24 h at 37 • C in a flat-bottom 96-well plate in 0.1% DMSO, PepTivator SARS-CoV-2 Prot S, Prot M and Prot N (1 and Dynabeads Human T activator CD3/CD28 (GibcoThermo Fisher Scientific Baltics UAB, Lithuania) as a positive control.…”

“…The results were expressed as the frequency in the activation induced molecules (CD25 + CD134 + ) ratio obtained after specific activation to negative non-stimulated control. A ratio > 3 in one of the specific SARS-CoV-2 peptides was considered positive as previously described [13], and representative examples are summarized in Figure S1.…”