Prion search and cellular prion protein expression in stranded dolphins

Area of Science:

• Veterinary Neurology
• Marine Mammal Medicine
• Prion Disease Research

Background:

• A recent prion disease (PD) case in a bottlenose dolphin prompted an investigation into prion protein (PrPSc) presence in stranded cetaceans.
• The study examined brain and lymphoid tissues from striped, bottlenose, and Risso's dolphins stranded between 2007-2012.

Discussion:

• Microscopic encephalitis lesions were found in some dolphins, but no spongiform changes indicative of PD.
• Cellular prion protein (PrPC) was immunoreactive in the brain and lymphoid tissues of the examined dolphins.
• Immunohistochemistry and Western blot analyses did not detect PrPSc deposition, ruling out active prion disease in this cohort.

Key Insights:

• Despite negative PrPSc findings, the occurrence of PD in a wild dolphin remains a significant concern.
• The presence of PrPC in cetacean tissues warrants further investigation into prion biology.
• This study underscores the importance of monitoring marine mammals for emerging infectious diseases.

Outlook:

• Further research is needed to understand the potential for prion transmission within and between cetacean species.
• Continued surveillance of stranded marine mammals is crucial for early detection of diseases like PD.
• Findings contribute to cetacean conservation medicine and the broader understanding of prion diseases in wildlife.