Research suggests Pfizer-BioNTech COVID-19 vaccine reprograms innate immune responses

Jorge Domínguez-Andrés and colleagues say that while the vaccine has been shown to be up to 95% effective in preventing infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and subsequent COVID-19, little is known about the broad effects the vaccine may have on the innate and adaptive immune responses.

In the current study (not peer-reviewed*), the research team from Radboud University Medical Center and Erasmus MC in the Netherlands, and the Helmholtz-Centre for Infection Research (HZI), Hannover Medical School (MHH), and the University of Bonn, in Germany, confirmed the efficacy of BNT162b2 vaccination at inducing effective humoral and cellular immunity against several SARS-CoV-2 variants.

However, they also showed that the vaccine altered the production of inflammatory cytokines by innate immune cells following stimulation with both specific (SARS-CoV-2) and non-specific (viral, fungal and bacterial) stimuli.

Following vaccination, innate immune cells had a reduced response to toll-like receptor 4 (TLR4), TLR7 and TLR8 – all ligands that play an important role in the immune response to viral infection.

Neta and colleagues also found that cytokine responses to fungi were increased following vaccination.

The mRNA BNT162b2 vaccine induces complex functional reprogramming of innate immune responses, which should be considered in the development and use of this new class of vaccines,” writes the team.

A pre-print version of the research paper is available on the medRxiv* server. A preprint is a version of a scholarly or scientific paper that precedes formal peer review and publication in a peer-reviewed scholarly or scientific journal.