Influenza B vaccine lineage selection--an optimized trivalent vaccine.

Epidemics of seasonal influenza viruses cause considerable morbidity and mortality each year. Various types and subtypes of influenza circulate in humans and evolve continuously such that individuals at risk of serious complications need to be vaccinated annually to keep protection up to date with circulating viruses. The influenza vaccine in most parts of the world is a trivalent vaccine, including an antigenically representative virus of recently circulating influenza A/H3N2, A/H1N1, and influenza B viruses. However, since the 1970s influenza B has split into two antigenically distinct lineages, only one of which is represented in the annual trivalent vaccine at any time. We describe a lineage selection strategy that optimizes protection against influenza B using the standard trivalent vaccine as a potentially cost effective alternative to quadrivalent vaccines.Sera used in this research were kindly provided by the following collaborators: for Australia by Dr. Ian Barr, WHO Collaborating Center, Melbourne, Australia, pediatric sera for the United States by Dr. Jackie Katz, WHO Collaborating Center, Atlanta, US, for Japan by Dr. Takato Odagiri, WHO Collaborating Center, Tokyo, Japan, for China by Dr. Yuelong Shu, WHO Collaborating Center, Beijing, China, for the United Kingdom by Dr. John Wood, NIBSC, Hertfordshire, UK. Additional thanks to Drs Nancy Cox, Michael Shaw, and Alexander Klimov. This work was supported by European Union FP7 program EMPERIE (22349). JMF is supported by a Fellowship in Biomedical Informatics from the Medical Research Council (UK) and a Junior Research Fellowship from Homerton College, Cambridge. Funded by: ERCPMC grant number: FP7 22349.This is the final version of the article. It first appeared from Elsevier via https://doi.org/10.1016/j.vaccine.2016.01.04

The confounded effects of age and exposure history in response to influenza vaccination

Numerous studies have explored whether the antibody response to influenza vaccination in elderly adults is as strong as it is in young adults. Results vary, but tend to indicate lower post-vaccination titers (antibody levels) in the elderly, supporting the concept of immunosenescence-the weakening of the immunological response related to age. Because the elderly in such studies typically have been vaccinated against influenza before enrollment, a confounding of effects occurs between age, and previous exposures, as a potential extrinsic reason for immunosenescence. We conducted a four-year study of serial annual immunizations with inactivated trivalent influenza vaccines in 136 young adults (16 to 39 years) and 122 elderly adults (62 to 92 years). Compared to data sets of previously published studies, which were designed to investigate the effect of age, this detailed longitudinal study with multiple vaccinations allowed us to also study the effect of prior vaccination history on the response to a v

B Cell Immunosenescence

Innate and adaptive immune responses decline with age, leading to greater susceptibility to infectious diseases and reduced responses to vaccines. Diseases are more severe in old than in young individuals and have a greater impact on health outcomes such as morbidity, disability, and mortality. Aging is characterized by increased low-grade chronic inflammation, so-called inflammaging, that represents a link between changes in immune cells and a number of diseases and syndromes typical of old age. In this review we summarize current knowledge on age-associated changes in immune cells with special emphasis on B cells, which are more inflammatory and less responsive to infections and vaccines in the elderly. We highlight recent findings on factors and pathways contributing to inflammaging and how these lead to dysfunctional immune responses. We summarize recent published studies showing that adipose tissue, which increases in size with aging, contributes to inflammaging and dysregulated B cell function