Twelve months after the first SARS-CoV-2 cases in Wuhan, the FDA approved the firstCOVID-19 vaccine (Pfizer-BioNTech). Early studies on healthcare workers showed thatantibody levels, especially against the Spike protein, declined within six months,particularly in those without prior infection. However, previously infected individualshad stronger and longer-lasting responses. The vaccine induces a Th1-type T cellresponse, linked to milder disease, and activates follicular helper T cells and B cellresponses, although antibody levels drop over time. Immune responses also differ by sex,with females showing stronger humoral responses. Key priorities include understandinghumoral fluctuations, characterizing cellular immunity, and correlating both responses.
Not Provided
Other: Evaluation of the T cell response in terms of IFN-γ measured by ELISpot
The evaluation of the T cell response will be performed by quantifying the frequencies of
SARS-CoV-2-specific T cells producing IFN-γ using an enzyme-linked immunospot assay
(ELISpot), with cryopreserved PBMC collected at the designated timepoints (T0, T1, T2,
T3, and T4)
healthcare workers group
Inclusion Criteria:
- Male and/or female sex
Age ≥18 years
Completion of the SARS-CoV-2 vaccination cycle with the Pfizer-BioNTech vaccine
Informed consent for the storage of biological material at the San Raffaele Hospital
Biological Resource Center (with protocol related to the BioVAC study approved by the
Ethics Committee: 17/INT/2022)
Availability of at least two aliquots of PBMC collected at the completion of the
vaccination cycle and frozen at the CRB
Exclusion Criteria:
- none donor group
Inclusion Criteria:
- consent for sample collection and storage in the Biobank between 2016 and 2018
Exclusion Criteria:
- none
IRCCS Ospedale San Raffaele
Milano, Italy
Patrizia Rovere Querini, PhD, MD, Principal Investigator
IRCCS Ospedale San Raffaele