Open AccessAnti-Prion Screening for Acridine, Dextran, and Tannic Acid using Real Time–Quaking Induced Conversion: A Comparison with PrPSc-Infected Cell Screening
Author(s) -
Jae Wook Hyeon,
Su Yeon Kim,
Sol Moe Lee,
Jeongmin Lee,
Seong Soo A. An,
Myung Koo Lee,
Yeong Seon Lee
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0170266
Subject(s) - tannic acid , chemistry , prion protein , acridine , microbiology and biotechnology , western blot , cell , biochemistry , biology , gene , medicine , disease , organic chemistry , pathology
Prion propagation is mediated by the structural alteration of normal prion protein (PrP C ) to generate pathogenic prion protein (PrP Sc ). To date, compounds for the inhibition of prion propagation have mainly been screened using PrP Sc -infected cells. Real time–quaking-induced conversion (RT-QuIC) is one alternative screening method. In this study, we assessed the propagation inhibition effects of known anti-prion compounds using RT-QuIC and compared the results with those from a PrP Sc -infected cell assay. Compounds were applied to RT-QuIC reactions at 0 h or 22 h after prion propagation to determine whether they inhibited propagation or reduced amplified aggregates. RT-QuIC reactions in presence of acridine, dextran sulfate sodium (DSS), and tannic acid inhibited seeded aggregation with sporadic Creutzfeldt-Jakob disease at 0 h. After treatment at 22 h, amplified fluorescence was decreased in wells treated with either acridine or tannic acid. Compound activities were verified by western blot of RT-QuIC products and in a dye-independent conversion assay, the Multimer Detection System. Protease K-resistant PrP Sc fragments (PrP res ) were reduced by DSS and tannic acid in the PrP Sc -infected cell assay. Importantly, these inhibitory effects were similar despite different treatment times (0 h versus 3 days). Consequentially, RT-QuIC enabled the more specific classification of compounds according to action (i.e., inhibition of prion propagation versus reduction of amplified aggregates). RT-QuIC addresses the limitations of cell-based screening methods and can be used to further aid our understanding of the mechanisms of action of anti-prion compounds.