Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer

ABSTRACT

Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrP^C) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrP^C in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrP^C than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrP^C than males in the forehead and preorbital glands. The distribution of PrP^C within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrP^C to serve as possible sites of prion initial infection, propagation, and shedding.

KEYWORDS:

• Prion
• chronic wasting disease
• sex differences
• species differences
• disease prevalence
• cervid
• protein expression
• glands

Acknowledgments

We thank Margo Pybus and other staff from Alberta Environment and Parks, Fish and Wildlife, for considerable logistical assistance during sample collection, hunters for contributing samples, and Canadian Forces Base Wainwright for access to the base. We also thank Renée Douville for the original suggestion to examine prion levels in glands, Travis Bannatyne and Charlene Berkvens for efforts preparing for sample collection. Andrew Castle advised with capillary gel electrophoresis. Nathalie Daude, Trang Nguyen, and Arlene Oatway from the University of Alberta histological core services assisted with sample preparation and processing.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/19336896.2022.2079888

Additional information

Funding

This work would not have been possible without Alberta Conservation Association (Research Grant) funding that supported sample collection and the Alberta Prion Research Institute (part of Alberta Innovates) for funding the analysis of PrP^C in the glands [PEX19011].