The immune response to influenza in older humans: beyond immune senescence.

ABSTRACT: Despite widespread influenza vaccination programs, influenza remains a major cause of morbidity and mortality in older adults. Age-related changes in multiple aspects of the adaptive immune response to influenza have been well-documented including a decline in antibody responses to influenza vaccination and changes in the cell-mediated response associated with immune senescence. This review will focus on T cell responses to influenza and influenza vaccination in older adults, and how increasing frailty or coexistence of multiple (?2) chronic conditions contributes to the loss of vaccine effectiveness for the prevention of hospitalization. Further, dysregulation of the production of pro- and anti-inflammatory mediators contributes to a decline in the generation of an effective CD8 T cell response needed to clear influenza virus from the lungs. Current influenza vaccines provide only a weak stimulus to this arm of the adaptive immune response and rely on re-stimulation of CD8 T cell memory related to prior exposure to influenza virus. Efforts to improve vaccine effectiveness in older adults will be fruitless until CD8 responses take center stage.

SUBMITTER: McElhaney JE 

PROVIDER: S-EPMC7204009 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature