High-dose influenza vaccine favors acute plasmablast responses rather than long-term cellular responses

Publication date: Available online 26 July 2016
Source:Vaccine
Author(s): Jin Hyang Kim, H. Keipp Talbot, Margarita Mishina, Yuwei Zhu, Jufu Chen, Weiping Cao, Adrian J. Reber, Marie R. Griffin, David K. Shay, Sarah M. Spencer, Suryaprakash Sambhara
High-dose (HD) influenza vaccine shows improved relative efficacy against influenza disease compared to standard-dose (SD) vaccine in individuals ⩾65years. This has been partially credited to superior serological responses, but a comprehensive understanding of cell-mediated immunity (CMI) of HD vaccine remains lacking. In the current study, a total of 105 participants were randomly administered HD or SD vaccine and were evaluated for serological responses. Subsets of the group (n=12–26 per group) were evaluated for B and T cell responses at days 0, 7, 14 and 28 post-vaccination by flow cytometry or ELISPOT assay. HD vaccine elicited significantly higher hemagglutination inhibition (HI) titers than SD vaccine at d28, but comparable titers at d365 post-vaccination. HD vaccine also elicited higher vaccine-specific plasmablast responses at d7 post-vaccination than SD vaccine. However, long-lived memory B cell induction, cytokine-secreting T cell responses and persistence of serological memory were comparable regardless of vaccine dose. More strategies other than increased Ag amount may be needed to improve CMI in older adults.Trial Registration: ClinicalTrials.gov NCT 01189123



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