Safety and Optimisation of Radiation Sterilization in Tissue Banking: Studies on Functional Properties of Irradiated Tissue Grafts

Closed for Proposals

Project Type

Coordinated Research Project

Project Code

E31006

CRP

1767

Approved Date

7 December 2009

Project Status

Closed

Start Date

18 March 2010

Expected End Date

31 December 2015

Completed Date

30 March 2017

Description

To assure safety of patients receiving tissue allografts during surgical treatment, several decontamination or sterilization procedures are implemented during the processing. Irradiation of tissue allografts is one of the developed and widely used methods for sterilization in the world. Gamma rays, X-rays, and electron beams have been used with doses ranging from 15 to 80 kGy. Controversies exist regarding the “optimal dose” for sterilisation since radiation can evoke numerous changes in tissues structure resulting in its change in functionality. The major aim in the project is to facilitate research to find the optimal radiation dose and processing methods for several tissues and disseminate the results in IAEA Member States. Therefore, radiation-induced effects on tissue grafts processed and preserved by different methods will be studied. The newly acquired knowledge established from harmonized research methodologies will be useful in providing high quality tissue allografts.

Objectives

To assure safety of patients receiving tissue allografts during surgical treatment, several decontamination or sterilization procedures are implemented during the processing. Irradiation of tissue allografts is one of the developed and widely used methods for sterilization in the world. Gamma rays, X-rays, and electron beams have been used with doses ranging from 15 to 80 kGy. Controversies exist regarding the “optimal dose” for sterilisation since radiation can evoke numerous changes in tissues structure resulting in its change in functionality. The major aim in the project is to facilitate research to find the optimal radiation dose and processing methods for several tissues and disseminate the results in IAEA Member States. Therefore, radiation-induced effects on tissue grafts processed and preserved by different methods will be studied. The newly acquired knowledge established from harmonized research methodologies will be useful in providing high quality tissue allografts.

Specific Objectives

There are limited studies that have been published, however, they have not been standardized and thus comparability is difficult
and, in some cases, not possible. As a result, controversies exist regarding the optimal dose for sterilisation since radiation can
evoke numerous changes in tissue structure resulting in its change in functionality. Therefore, this research programme is to
validate the optimal sterilization dose and processing methods for several tissues providing allograft sterility (SAL 10-6) without
compromising tissue biological or structural function for clinical use. Important tissue allografts to be investigated are: bone,
tendon, cartilage, skin, amniotic membrane, vascular grafts, and heart valves. For successful distribution of safe and good
quality tissue allografts, it is important to understand: Interaction between processing methods and irradiation process, Dose
response relationship and validation of relevant physical, chemical, biological and clinical end-points, Effect of irradiation
conditions (temperature, oxygen, water content, dose rate, radio-protectants, etc.) on biological properties of tissue allografts, In
order to improve tissue banking processing and preservation protocols the following questions need to be answered: What type
of testing methods should be applied for tissue allografts? What is the optimum processing and preservation method to
preserve functionality of tissue grafts? What is the maximum tolerated irradiation dose for different levels of damage in different
tissue allografts (type of tissue, method of processing)? Which processing combinations have the highest potential reducing the
radiation-induced tissue toxicity in specific tissues? Which processing combinations have the highest potential preserving
functionality of irradiated tissues? Is there any relation of dose-rate on physical, chemical, biological properties of tissue
allografts?

Impact

An overall assessment indicates that the participating institutes are more than capable of performing relevant research with regard to
optimisation of the radiation sterilization dose for tissue allografts. All institutes perform well, or above, and have produced new data and show considerable research progress. Several institutes were able to receive new or extra funding from national authorities and expanding their research on radiation sterilization, tissue procurement and tissue processing.

Relevance

The CRP is very relevant to the Agency’s project and to Member States (in particular LMI-countries relying on radiation sterilization of tissue allografts as the only affordable sterilization method.

CRP Publications

AUL, AUS

Methodological

2012

Morales Pedraza, J. and M. R. Herson (2012). "The importance of ethic in the field of human tissue banking." Cell Tissue Bank 13(1): 103-117

https://www.ncbi.nlm.nih.gov/pubmed/21161412