Hydrogen Peroxide Gas Plasma Sterilizer Combined with Dielectric Barrier Discharge and Corona Discharge Inactivates Prions

Akikazu Sakudo,Yosuke Tsuji

doi:10.3390/app11209777

Abstract

Prions are highly resistant to physical or chemical damage, although previous studies have shown that STERRAD®, a hydrogen gas plasma sterilizer using radiofrequency (RF) discharge, has an inactivation effect. Here, the effect of hydrogen peroxide gas combined with dielectric barrier discharge (DBD) plasma and corona discharge plasma using a RENO-S130 sterilizer on scrapie prions was examined. Scrapie prion-infected mouse brain homogenate was air-dried on a cover glass, sealed in a Tyvek pouch, and subjected to RENO-S130 treatment using either non-lumen mode (28 min) or Eco mode (45 min) with hydrogen peroxide gas derived from 50% hydrogen peroxide. Control (untreated) samples were prepared on a cover glass using the same procedure but without exposure to RENO-S130. PrPres (proteinase K (PK)-resistant prion protein), an index of the conformational variant of prion protein (PrPSc), was decreased by treatment with RENO-S130 under both modes of operation. Specifically, PrPres was identified after the 1st and 2nd cycles of protein misfolding cyclic amplification (PMCA) in control samples but was below the detection limit in RENO-S130-treated samples. A bioassay showed that treatment of prions with RENO-S130 (non-lumen or Eco mode) significantly prolonged mouse survival time. Taken together, these findings show hydrogen peroxide gas combined with DBD/corona discharge plasma can inactivate prions by reducing prion propagation and prion infectivity. This treatment is potentially applicable to the sterilization of prion-contaminated heat-sensitive medical devices.

Highlights

Samples derived from prion (Chandler strain)-infected mouse brain homogenate on a glass surface were subjected to RENO-S130 treatment (Figure 1)
The RENO-S130 instrument operates in two modes: a nonlumen mode that is suitable for medical devices that require surface sterilization only, or an
The prion agent is a pathogen that is highly resistant to inactivation using standard chemical and physical disinfection methods

Summary

Introduction

Transmissible spongiform encephalopathies (TSEs), referred to as prion diseases, are responsible for deadly neurodegenerative disorders including human prion diseases such as Creutzfeldt–Jakob disease (CJD), fatal familial insomnia (FFI), and GerstmannSträussler-Scheinker syndrome (GSS) as well as animal prion diseases such as bovine spongiform encephalopathy (BSE) in cattle, chronic wasting disease (CWD) in cervids, and scrapie in goat and sheep [1]. Prion diseases are transmissible and can be caused by infection or inheritance, while most human prion diseases (85% to 90%) are sporadic and of unspecified origin [1,2]. The prion agent is highly resistant to inactivation and poses a risk to public health. Environmental and food contamination with prions may play a role in its transmission

Methods

Results

Conclusion