Chemical inactivation of prion

朊病毒的化学灭活

• 批准号: 10556069
• 负责人: SHINAGAWA Morikazu
• 金额: $ 8.13万
• 依托单位: Obihiro University of Agriculture and Veterinary Medicine
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10556069/
• 关键词: prion; Chemical lnactivation; liquid Ethylene Oxide; Glycidol; グリシドー; グリシドール; エチレンオキサイド

Prion decontamination requires very harsh treatment such as soaking in concentrated sodium hydroxide, sodium hypochlorite or autoclaving at 134℃ to eliminate all infectivity. However, as Iong as the daily disinfection of medical equipment is concerned, the infectivity titer of the contaminated materials is relatively low. Therefore, a mild decontamination procedure would be adequate so that contaminated materials are not damaged by severe chemical or physical treatments. Liquid ethylene oxide (LEO) was found to cause a dose-dependent decrease in prion infectivity in 1% scrapie-mouse brain homogenates, and the reduction attained by treatment with 2% LEO at 25℃ for 40 h reached more than 10^<-5>. LEO is, however, difficult to handle and takes relatively long time to inactive prion. Therefore, we screened three epoxides, β-propiolactone, propylene oxide, and glycidol (GLD), which resemble to EO in their structures but are easier in handling than LEO.Among these chemicals, GLD worked most effectively and degraded prion protein into small fragments. As a result of the bioassay, treatment with 3% GLD for 5 hr and 5% GLD for 2, 5 hr or 12 hr at room temperature prolonged the mean incubation time by 44, 30, 110 and 73 days, respectively. From dose-incubation time standard curve, the decrease in infectivity titers was estimated as 10a^<-3> or more. Therefore, degradation of prion protein by GLD decreased the scrapie infectivity. Effect of GLD was enhanced by high pH around 8 and presence of some salt such as 0.15 M NaCl together with higher temperature of 50℃. However, the mouse-bioassay are not available at present.

朊病毒去污需要非常苛刻的处理，如浸泡在浓氢氧化钠、次氯酸钠中或在134℃下高压灭菌，以消除所有传染性。但就医疗器械的日常消毒而言，污染物的传染性滴度相对较低。因此，温和的去污程序就足够了，这样污染的材料就不会被严重的化学或物理处理损坏。发现液态环氧乙烷（LEO）可使1%羊瘙痒症小鼠脑匀浆中朊病毒感染率呈剂量依赖性降低，2%LEO在25℃下处理40 h可使朊病毒感染率降低10%以上<-5>。然而，LEO难以处理，并且需要相对较长的时间来使朊病毒失活。因此，我们筛选了三种结构类似EO但操作简单的环氧化合物，β-丙内酯、环氧丙烷和缩水甘油（GLD），其中GLD的作用最有效，可将朊病毒蛋白降解成小片段。作为生物测定的结果，在室温下用3%GLD处理5小时和5%GLD处理2、5小时或12小时分别使平均孵育时间延长44、30、110和73天。根据剂量-孵育时间标准曲线，感染性滴度的降低估计为10 μ g<-3>或更多。因此，通过GLD降解朊病毒蛋白降低了羊瘙痒病的感染性。当pH值在8左右时，在50℃的高温下，加入0.15M NaCl等盐，可以提高GLD的效果。然而，目前还没有小鼠生物测定法。

项目成果

Laplanche,J.-L. 等: "Scrapie, Chronic Wasting Disease, and Transmissible Mink Encephalopathy. In Prion Biology and Diseases"Cold Spring Harbor Press. 794 (1999)

Laplanche, J.-L. 等人：“痒病、慢性消耗性疾病和传染性水貂脑病。朊病毒生物学和疾病”冷泉港出版社 794 (1999)。

Horiuchi, M., Ishiguro, N., Nagasawa, H., Toyoda, Y., Shinagawa, M.: "Genomic structure of the bovine PrP gene and complete nucleotide sequence of bovine PrP cDNA." Animal Genetics. 29. 37-40 (1998)

Horiuchi, M.、Ishiguro, N.、Nagasawa, H.、Toyoda, Y.、Shinakawa, M.：“牛 PrP 基因的基因组结构和牛 PrP cDNA 的完整核苷酸序列。”

Takahashi H.等: "Characterization of antibodies raised against bivine-PrP-peptides"J Neurovirol. 5. 300-307 (1999)

Takahashi H.等人：“针对牛-PrP-肽产生的抗体的表征”J Neurovirol.5.300-307(1999)。

Laplanche.J.-L., et al.: "Scrapie, Chronic Wasting Disease, and Transmissible Mink Encephalopathy. In Prion Biology and Diseases, Monograph 38(Prusiner.S.B.ed)"Cold Spring Harbor Laboratory Press. 794 (1999)

Laplanche.J.-L.等人：“痒病、慢性消耗性疾病和传染性水貂脑病。朊病毒生物学和疾病，专着 38（Prusiner.S.B.ed）”冷泉港实验室出版社。

Horiuchi, M.et al.: "Genomic structure of the bovine PrP gene and complete nucleotide sequence of bovine PrP cDNA." Animal Genetics. 29. 37-40 (1998)

Horiuchi, M.et al.：“牛 PrP 基因的基因组结构和牛 PrP cDNA 的完整核苷酸序列。”