# Expression of the cellular prion protein by mast cells in white-tailed deer carotid body, cervical lymph nodes and ganglia

## TL;DR

This paper explores how prions might enter the nervous system in deer by examining prion protein expression in specific tissues.

## Contribution

The study identifies mast cells in carotid bodies as potential sites for prion entry into the central nervous system.

## Key findings

- Mast cells in carotid bodies express prion protein.
- Carotid bodies are connected to brainstem nuclei linked to early prion neuroinvasion.
- Prions may enter the CNS via blood-borne exposure in carotid bodies.

## Abstract

Chronic wasting disease (CWD) is a transmissible and fatal prion disease that affects cervids. While both oral and nasal routes of exposure to prions cause disease, the spatial and temporal details of how prions enter the central nervous system (CNS) are unknown. Carotid bodies (CBs) are structures that are exposed to blood-borne prions and are densely innervated by nerves that are directly connected to brainstem nuclei, known to be early sites of prion neuroinvasion. All CBs examined contained mast cells expressing the prion protein which is consistent with these cells playing a role in neuroinvasion following prionemia.