The VITAL vaccination study has been completed. The last sample from the 12-months follow-up after the pneumococcal conjugate (PCV13) vaccination was collected on 14 October 2021. Out of 326 participants, 285 participated in the PCV13 vaccination follow-up, of whom 280 completed the six-months follow-up. WP2 collected 55,711 vials of biological material for immunological analyses. HI data analysis is in process.
Initial data on pneumococcal serotype specific antibody levels have been obtained. At first glance it seems that most individuals reacted to the vaccines. The data suggests that older individuals have a delayed antibody response based on the level of antibodies as well as the number of serotypes they responded to.
Analyses of baseline immune cell profiles have revealed specific immune clusters, which can be used to classify individuals (irrespective of age) and correlate to specific clinical phenotypes and vaccination response. Furthermore, the data shows that stability of the immune cell subset composition over a year is an important factor associated with expansion of a subset of T cells important for developing proper antibody responses.
The Aim of WP2
WP2 aims to obtain a better insight into changes in the immune response that comes with age. It aims to evaluate the impact of (external) factors on vaccine performance in ageing populations to formulate evidence-based rationale strategies for improving immunity to infections by vaccination in this group, for example, vaccinating pre-ageing adults. Based on a prospective study design in three age groups — elderly (65 years +), pre-elderly (50-65) and adults (25-49) — the proposed work will contribute to the identification of immune profiles underlying the immunosenescence process.