Biography
Biography: Lorena E. Brown
Abstract
Vaccines that exert their effects solely through the induction of highly specific neutralising antibodies can be effective but their benefit diminishes in a scenario of vaccine mismatch or if a new subtype of virus emerges. Cross-protective responses, such as those invoked and continuously boosted by natural infection, probably account for why most individuals experience clinical influenza on only a few occasions during their lifetime in response to antigenically drifted influenza strains. Cross-reactive immunity may also provide some protection against severe illness following infection with virus of a novel subtype. Current split virus vaccines induce very little if any cross-protective immunity against heterologous subtypes of virus and vaccine strategies that enable such responses would represent a substantial improvement. Proof of principle studies using two different strategies that potentially induce both highly specific neutralising antibody and heterosubtypic immunity in the form of cross-reactive cytotoxic T cells will be reported. The first of these is delivery of live virus by a non-productive route and the second is delivery of split virus vaccine in combination with an epitope-based TLR2-containing component. The “dose-sparing” effects of such vaccines will be discussed as well as the influence of routes of inoculation on the balance of antibody versus cytotoxic T cell immunity and the potency of the viral clearing response.