HaHV-1 is a reemerging viral pathogen characterised by events of mass mortality in both wild and farmed Australian abalone. Due to our limited understanding of the specificities of the abalone immune response, we currently do not possess any treatments against this pathogen despite its imminent risk on Australia’s abalone populations.
To examine the potential of immune priming against lethal HaHV-1 challenge, naive abalone were injected with non-specific synthetic nucleic acid prior to immersion in HaHV-1 infectious water. We have been able to demonstrate after optimisation of an appropriate delivery method, that immune priming abalone at least 5 days prior to challenge, provided significant protection against lethal viral challenge with protection lasting up to 121 days since initial viral infection, when compared to un-primed controls. Additionally, we demonstrated that immune priming induces the transcription of two antiviral interferon stimulated genes (ISGs), Viperin and IRF-1 in abalone haemolymph, indicating an enhanced immune response upon administration of the priming agent which may alter susceptibility to HaHV-1 challenge in vivo, however further work needs to be performed to determine this.
This work provides an insight into the potential of immune priming as an antiviral strategy in protecting Australia’s abalone against HaHV-1 infection.