Age-related immune response heterogeneity to SARS-CoV-2 vaccine BNT162b2

Individuals above 80 years of age vaccinated with a single dose of BNT162b2 mRNA vaccine showed remarkable decline of neutralizing antibodies against SARS-CoV-2 especially for variants B.1.1.7, P.1 and B.1.351, compared  with younger individuals. However, following the second dose, neutralization against these variants was detectable regardless of age. The memory B cells specific for SARS-CoV-2 spike were abundant in the younger individuals compared with elderly individuals. In the elderly individuals, SARS-CoV-2 spike specific T cell responses of IFN-gamma and IL-2 were also decreased compared with those of younger individuals.