PLGA/PLA micro- and nanoparticle formulations serve as antigen depots and induce elevated humoral responses after immunization of Atlantic salmon (Salmo salar L.)

► PLGA/PLA nano- and microparticles as adjuvants in Atlantic salmon. ► Conventional oil-based vaccines induce humoral responses and serve as depot. ► Polymeric particles show the same qualities. ► Particles enable antigen delivery to lymphoid tissues in salmon. ► Particles have adjuvant properties in Atlantic salmon.