Systematic enhancement of microbial decontamination efficiency in bone graft processing by means of high hydrostatic pressure using Escherichia coli as a model organism

IF 3.2 4区 医学 Q2 ENGINEERING, BIOMEDICAL
Henrike Loeffler, Janine Waletzko-Hellwig, Ralf-Joerg Fischer, Mirko Basen, Marcus Frank, Anika Jonitz-Heincke, Rainer Bader, Annett Klinder
{"title":"Systematic enhancement of microbial decontamination efficiency in bone graft processing by means of high hydrostatic pressure using Escherichia coli as a model organism","authors":"Henrike Loeffler,&nbsp;Janine Waletzko-Hellwig,&nbsp;Ralf-Joerg Fischer,&nbsp;Mirko Basen,&nbsp;Marcus Frank,&nbsp;Anika Jonitz-Heincke,&nbsp;Rainer Bader,&nbsp;Annett Klinder","doi":"10.1002/jbm.b.35383","DOIUrl":null,"url":null,"abstract":"<p>To obtain bone allografts that are safe for transplantation, several processing steps for decellularization and decontamination have to be applied. Currently available processing methods, although well-established, may interfere with the biomechanical properties of the bone. High hydrostatic pressure (HHP) is known to devitalize tissues effectively while leaving the extracellular matrix intact. However, little is known about the inactivation of the contaminating microorganisms by HHP. This study aims to investigate the ability of high-pressure decontamination and to establish a treatment protocol that is able to successfully inactivate microorganisms with the final goal to sterilize bone specimens. Using <i>Escherichia coli (E. coli)</i> as a model organism, HHP treatment parameters like temperature and duration, pressurization medium, and the number of treatment cycles were systematically adjusted to maximize the efficiency of inactivating logarithmic and stationary phase bacteria. Towards that we quantified colony-forming units (cfu) after treatment and investigated morphological changes via Field Emission Scanning Electron Microscopy (FESEM). Additionally, we tested the decontamination efficiency of HHP in bovine cancellous bone blocks that were contaminated with bacteria. Finally, two further model organisms were evaluated, namely <i>Pseudomonas fluorescens</i> as a Gram-negative microorganism and <i>Micrococcus luteus</i> as a Gram-positive representative. A HHP protocol, using 350 MPa, was able to sterilize a suspension of stationary phase <i>E. coli</i>, leading to a logarithmic reduction factor (log RF) of at least −7.99 (±0.43). The decontamination of bone blocks was less successful, indicating a protective effect of the surrounding tissue. Sterilization of 100% of the samples was achieved when a protocol optimized in terms of treatment temperature, duration, pressurization medium, and number and/or interval of cycles, respectively, was applied to bone blocks artificially contaminated with a suspension containing 10<sup>4</sup> cfu/mL. Hence, we here successfully established protocols for inactivating Gram-negative model microorganisms by HHP of up to 350 MPa, while pressure levels of 600 MPa were needed to inactivate the Gram-positive model organism. Thus, this study provides a basis for further investigations on different pathogenic bacteria that could enable the use of HHP in the decontamination of bone grafts intended for transplantation.</p>","PeriodicalId":15269,"journal":{"name":"Journal of biomedical materials research. Part B, Applied biomaterials","volume":null,"pages":null},"PeriodicalIF":3.2000,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jbm.b.35383","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of biomedical materials research. Part B, Applied biomaterials","FirstCategoryId":"5","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/jbm.b.35383","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, BIOMEDICAL","Score":null,"Total":0}
引用次数: 0

Abstract

To obtain bone allografts that are safe for transplantation, several processing steps for decellularization and decontamination have to be applied. Currently available processing methods, although well-established, may interfere with the biomechanical properties of the bone. High hydrostatic pressure (HHP) is known to devitalize tissues effectively while leaving the extracellular matrix intact. However, little is known about the inactivation of the contaminating microorganisms by HHP. This study aims to investigate the ability of high-pressure decontamination and to establish a treatment protocol that is able to successfully inactivate microorganisms with the final goal to sterilize bone specimens. Using Escherichia coli (E. coli) as a model organism, HHP treatment parameters like temperature and duration, pressurization medium, and the number of treatment cycles were systematically adjusted to maximize the efficiency of inactivating logarithmic and stationary phase bacteria. Towards that we quantified colony-forming units (cfu) after treatment and investigated morphological changes via Field Emission Scanning Electron Microscopy (FESEM). Additionally, we tested the decontamination efficiency of HHP in bovine cancellous bone blocks that were contaminated with bacteria. Finally, two further model organisms were evaluated, namely Pseudomonas fluorescens as a Gram-negative microorganism and Micrococcus luteus as a Gram-positive representative. A HHP protocol, using 350 MPa, was able to sterilize a suspension of stationary phase E. coli, leading to a logarithmic reduction factor (log RF) of at least −7.99 (±0.43). The decontamination of bone blocks was less successful, indicating a protective effect of the surrounding tissue. Sterilization of 100% of the samples was achieved when a protocol optimized in terms of treatment temperature, duration, pressurization medium, and number and/or interval of cycles, respectively, was applied to bone blocks artificially contaminated with a suspension containing 104 cfu/mL. Hence, we here successfully established protocols for inactivating Gram-negative model microorganisms by HHP of up to 350 MPa, while pressure levels of 600 MPa were needed to inactivate the Gram-positive model organism. Thus, this study provides a basis for further investigations on different pathogenic bacteria that could enable the use of HHP in the decontamination of bone grafts intended for transplantation.

Abstract Image

以大肠杆菌为模型生物,通过高静水压系统提高骨移植加工过程中的微生物净化效率
要获得可安全移植的骨异体移植物,必须采用多个处理步骤进行脱细胞和去污。目前可用的处理方法虽然已经成熟,但可能会干扰骨的生物力学特性。众所周知,高静水压(HHP)能有效地使组织脱细胞,同时使细胞外基质保持完整。然而,人们对高静压灭活污染微生物的情况知之甚少。本研究旨在调查高压去污的能力,并建立一种能够成功灭活微生物的处理方案,最终实现骨标本灭菌的目标。我们以大肠杆菌(E. coli)为模型生物,系统地调整了高压处理参数,如温度和持续时间、加压介质和处理循环次数,以最大限度地提高对数期和静止期细菌的灭活效率。为此,我们对处理后的菌落形成单位(cfu)进行了量化,并通过场发射扫描电子显微镜(FESEM)对形态变化进行了研究。此外,我们还在受到细菌污染的牛松质骨块中测试了 HHP 的去污效率。最后,我们又对两种模式生物进行了评估,即作为革兰氏阴性微生物的荧光假单胞菌和作为革兰氏阳性微生物代表的黄绿微球菌。采用 350 兆帕的高压灭菌方案能够对静止期大肠杆菌悬浮液进行灭菌,使对数还原因子(log RF)至少达到 -7.99 (±0.43)。骨块的净化效果较差,这表明周围组织具有保护作用。如果对人工污染了含有 104 cfu/mL 悬浮液的骨块采用在处理温度、持续时间、加压介质、循环次数和/或间隔方面分别进行了优化的方案,则可实现 100% 的样本灭菌。因此,我们在此成功建立了通过高达 350 兆帕的高压灭活革兰氏阴性模式微生物的方案,而灭活革兰氏阳性模式微生物则需要 600 兆帕的压力水平。因此,这项研究为进一步研究不同的病原菌提供了基础,从而使高压电能够用于净化用于移植的骨移植物。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
CiteScore
7.50
自引率
2.90%
发文量
199
审稿时长
12 months
期刊介绍: Journal of Biomedical Materials Research – Part B: Applied Biomaterials is a highly interdisciplinary peer-reviewed journal serving the needs of biomaterials professionals who design, develop, produce and apply biomaterials and medical devices. It has the common focus of biomaterials applied to the human body and covers all disciplines where medical devices are used. Papers are published on biomaterials related to medical device development and manufacture, degradation in the body, nano- and biomimetic- biomaterials interactions, mechanics of biomaterials, implant retrieval and analysis, tissue-biomaterial surface interactions, wound healing, infection, drug delivery, standards and regulation of devices, animal and pre-clinical studies of biomaterials and medical devices, and tissue-biopolymer-material combination products. Manuscripts are published in one of six formats: • original research reports • short research and development reports • scientific reviews • current concepts articles • special reports • editorials Journal of Biomedical Materials Research – Part B: Applied Biomaterials is an official journal of the Society for Biomaterials, Japanese Society for Biomaterials, the Australasian Society for Biomaterials, and the Korean Society for Biomaterials. Manuscripts from all countries are invited but must be in English. Authors are not required to be members of the affiliated Societies, but members of these societies are encouraged to submit their work to the journal for consideration.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信