Evaluation of anti-prion compounds targeting CWD using the RT-QuIC assay

Chronic wasting disease (CWD) is a prion disease affecting cervids, for which no effective therapeutic agents are currently available. The real-time quaking-induced conversion (RT-QuIC) assay is a highly sensitive and specific biochemical method for detecting the infectious prion protein (PrP^Sc) and it serves as a valuable tool for evaluating compounds that inhibit prion aggregation. In this study, the RT-QuIC assay was employed to screen nine compounds (ane138b, doxycycline, trehalose, 2-aminothiazole, resveratrol, trans-resveratrol, curcumin, nanocurcumin, and gossypeptin), including several previously reported to be effective in neurodegenerative diseases, for their antiprion activity. CWD was used as the seeding agent, and the relative amount of seeding activity was expressed as the SD₅₀ concentration. Ane138b, trehalose and 2-aminothiazol showed no inhibitory effect against CWD. In contrast, doxycyclin and trans-resveratrol significantly reduced SD₅₀ value by 5 log 10 at concentration of 50 μM, 25 μM, respectively, compared to the non-treated controls. Curcumin, resveratrol, and gossypeptin exhibited antiprion activity at a lower concentration of 12.5 μM. Notably, nanocurcumin showed the lowest effective concentration, inhibiting prion seeding activity at 6.25 μM. These findings indicate that some of the tested compounds exhibit strong inhibitory effects on prion aggregation and suggest their potential as candidates for anti-prion therapeutic agents. Further in vivo studies using animal models are required to assess their therapeutic applicability in prion diseases such as CWD.

Acknowledgements: This research was supported by Animal and Plant Quarantine Agency, Ministry for Agriculture, Food and Rural Affairs, Republic of Korea (B1543085-2025-27-0301).