OBJECTIVE: Most established prion inactivation methods were validated against scrapie agents, although those were found to be generally less thermostable than human prions. Thus, knowledge gaps regarding steam-sterilization kinetics of CJD prions should be filled and current guidelines reviewed accordingly.
METHODS: Prion inactivation through widely recommended steam sterilization at 134°C was assessed for several holding times by analysing the residual prion seeding activity using protein misfolding cyclic amplification (PMCA).
RESULTS: Scrapie 263K was found to be the least thermoresistant prion strain showing no seeding activity after 1.5 min at 134°C, while variant CJD was the most stable one demonstrating some seeding activity even after 18 min of steam sterilization. Sporadic CJD subtype VV2 exhibited residual seeding activity after 3 min, but no detectable activity after 5 min at 134°C.
CONCLUSIONS: Validated steam sterilization for 5 min at 134°C as previously recommended for the routine reprocessing of surgical instruments in contact with high-risk tissues is able to substantially reduce the seeding activity of CJD agents, provided that no fixating chemical disinfection has been performed prior to sterilization and that thorough cleaning has reduced the protein load on the surface to less than 100 μg per instrument.
目的:大多数已建立的朊病毒灭活方法已针对瘙痒病制剂进行了验证,
方法:通过使用蛋白质错误折叠循环扩增(PMCA)分析残留的朊病毒接种活性,评估了在134°C下广泛推荐的蒸汽灭菌对朊病毒灭活的几次保持时间。
结果:Scrapie263K被发现是在134°C下1.5分钟后没有播种活性的耐热性最低的朊病毒菌株,
结论:先前推荐的与高风险组织接触的手术器械的常规再处理在134°C下进行5分钟的经过验证的蒸汽灭菌能够大大减少CJD试剂的接种活性,