Effects of Aging on Primary and Secondary Vaccine Responses in a 15-Year Longitudinal Cohort

Age-associated changes in human adaptive immune responses to vaccination and infection have begun to be clear, particularly in the context of recurrent antigen exposures such as influenza vaccination.� Both young and elderly individuals are also able to form new primary immune responses in response to novel antigens, but the extent and underlying reasons for impaired primary responses in older subjects are not well understood. The purpose of this study is to use an existing, unique clinical cohort: the longitudinal Stanford-Ellison cohort of younger (18-40 years) and elderly (65 and older) subjects whose yearly influenza vaccine responses have been studied extensively since 2007, to gain molecular and cellular mechanistic insights into the impaired vaccine responses in the elderly