In vitro characterisation of factors controlling the innate immune response in Rainbow Trout (Oncorhynchus mykiss) In terms of traits and components the innate immune system of teleost fish is similar to that of mammals. Despite the fact that gene or protein orthology and conservation allow for function similarity the Whole Genome Duplication (WGD) that occurred early in the life of ray finned fishes permitted the formation of paralog genes with novel functions in fish. Therefore the aim of this thesis was focused towards the characterisation of selected factors able to regulate the innate immune response of rainbow trout and in salmonid cell models.<eng>