No evidence of immune exhaustion after repeated SARS-CoV-2 vaccination in vulnerable and healthy populations

No evidence of immune exhaustion after repeated SARS-CoV-2 vaccination in vulnerable and healthy populations

Frequent SARS-CoV-2 vaccination in vulnerable populations has raised concerns that this may contribute to T cell exhaustion, which could negatively affect the quality of immune protection. Herein, we examined the impact of repeated SARS-CoV-2 vaccination on T cell phenotypic and functional exhaustion in frail older adults in long-term care (n = 23), individuals on immunosuppressive drugs (n = 10), and healthy adults (n = 43), in Canada. Spike-sp…