Dynamics of CWD Prion Detection in Feces and Blood From Naturally Infected White-Tailed Deer

Authors

Francisca Bravo-Risi
Paulina Soto
Rebeca Benavente
Tracy A Nichols
Rodrigo Morales

Publication Date

11-17-2023

Journal

Scientific Reports

Abstract

Chronic wasting disease (CWD) is a prion disease affecting cervids. Confirmatory testing of CWD is currently performed postmortem in obex and lymphoid tissues. Extensive evidence demonstrates the presence of infectious prions in feces of CWD-infected deer using in vitro prion-amplification techniques and bioassays. In experimental conditions, this has been achieved as soon as 6-month post-inoculation, suggesting this sample type is a candidate for antemortem diagnosis. In the present study, we optimized the detection of CWD-prions in fecal samples from naturally infected, pre-clinical white-tailed deer by comparing protocols aiming to concentrate CWD-prions with direct spiking of the sample into the PMCA reactions. Results of this screening were compared with similar analyses made in blood. Our data shows that CWD-prion detection in feces using PMCA is best in the absence of sample pre-treatments. We performed a screening of 169 fecal samples, detecting CWD-prions with diagnostic sensitivity and specificity of 54.81% and 98.46%, respectively. In addition, the PMCA seeding activity of 76 fecal samples was compared with that on blood of matched deer. Our findings, demonstrate that CWD-prions in feces and blood are increased at late pre-clinical stages, exhibiting similar detection in both sample types (> 90% sensitivity) when PrP96GG animals are tested. Our findings contribute to understand prion distribution across different biological samples and polymorphic variants in white-tailed deer. This information is also relevant for the current efforts to identify platforms to diagnose CWD.

Keywords

Animals, Prions, Deer, Wasting Disease, Chronic, Feces

Comments

Supplementary Materials

Data Availability Statement

PMID: 37978207