Primed for success: Oyster parents treated with poly(I:C) produce offspring with enhanced protection against Ostreid herpesvirus type I infection.
The Pacific oyster (Crassostrea gigas) is farmed globally. Ostreid herpesvirus (OsHV-1) causes severe mortalities of farmed C. gigas. Management of OsHV-1 has proven difficult. Oysters treated with poly(I:C) exhibit enhanced protection (EP) against OsHV-1. This chemical treatment is highly effective, but it is not feasible to treat every oyster on a farm. To circumvent this practical limitation, previous studies on arthropods have suggested that EP can be transferred from parents to their offspring (trans-generational EP, TGEP). This suggests that the treatment of relatively few parents could be used to produce large numbers of offspring with TGEP. Here, we investigated TGEP in oysters to test whether it might be used as a cost effective management tool to control OsHV-1. We found that offspring (D-veliger larvae) produced from poly(I:C)-treated parents had double the chance of surviving exposure to OsHV-1 compared to controls. Furthermore, the larvae of poly(I:C)-treated parents contained elevated levels of mRNA encoding a key transcription factor that regulates antiviral immunity (IRF2). Poly(I:C) treatment had no effect on the survival of oyster parents. Hence, the enhanced immunity of their offspring could not be explained by genetic selection, and instead may reflect epigenetic reprogramming or maternal provisioning.
Macquarie University, Department of Biological Sciences, Sydney, NSW, Australia; Sydney Institute of Marine Science, Chowder Bay, Mosman, NSW, Australia. Electronic address: tim.green@mq.edu.au.
Timothy J
TJ
Green
La Trobe University, Department of Physiology, Anatomy and Microbiology, School of Life Sciences, Melbourne, Victoria, Australia.
Karla
K
Helbig
Flinders University, Department of Biological Sciences, Adelaide, South Australia, Australia.
Peter
P
Speck
Macquarie University, Department of Biological Sciences, Sydney, NSW, Australia; Sydney Institute of Marine Science, Chowder Bay, Mosman, NSW, Australia.
David A
DA
Raftos
D000818:Animals; D049896:Crassostrea / Q000187:drug effects* / Q000276:immunology*; D006564:Herpesviridae; D006566:Herpesviridae Infections / Q000662:veterinary*; D011070:Poly I-C / Q000276:immunology / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction
D011070:Poly I-C
Crassostrea; Invertebrate antiviral response; OsHV-1; Trained immunity; Trans-generational immune priming