The production of high affinity, class switched antibodies produced by B cells hinges on the effective differentiation of T follicular helper (Tfh) cells. Here we define conditions specifically enhancing Tfh differentiation and providing protection in a model of influenza infection. Tfh responses were associated with prolonged antigen presentation by Dendritic cells (DCs), which maintained T cell/DC interactions into stage 3 (>72 hours) of activation. Blocking stage 3 interactions ablated Tfh generation, demonstrating a causal link between T cell-DC behaviour and functional outcomes. The current data therefore explain how duration of antigen presentation affects the dynamics of T cell-DC interactions and consequently determine Tfh cell differentiation in the developing immune response.
Animal experimentation: All animals were specified pathogen free and maintained under standard animal house conditions at the University of Glasgow in accordance with local and UK Home Office Regulations.
- Shimon Sakaguchi, Osaka University, Japan
© 2015, Benson et al.
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