The International Atomic Energy Agency

(IAEA) research on radiation sterilization in

tissue banking Oleg Belyakov

Radiation Biologist

Applied Radiation Biology and Radiotherapy Section

Division of Human Health

Department of Nuclear Sciences and Applications

IAEA is involved more

than 30 years in the use

of the ionising radiation

techniques for tissue

banking

Pedraza JM. The Use of the Ionizing Radiation Technique for Tissue Sterilization: The International Atomic Energy Agency (IAEA) Experience: Nova Science; 2011.

Mr Jorge Morales

Pedraza, Radiation

and Tissue Banking

Programme former

Manager in the

Technical Cooperation

department of IAEA

• The use of tissue allografts in surgical procedures has

increased tremendously over the last several years.

• Radiation has been used to sterilize tissue allografts on a

large scale.

• Tissue banks use radiation doses just based on empirical

and/or historical data, or use a fixed dose of 15 or 25 kGy for

all tissue allografts.

• In order to improve the knowledge on radiosterilisation of

tissue allografts studies were designed and conducted

under controlled and validated conditions.

• Five main categories of tissues were studied: bone,

demineralized bone, cartilage allograft, skin and amnion.

IAEA Coordinated Research Project (CRP)

E31006 “Safety and Optimization of Radiation

Sterilization in Tissue Banking: Studies on

Functional Properties of Irradiated Tissue Grafts”

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16 participating institutions

from 16 IAEA Members States

Five year CRP (2010-2015, to be formally closed in 2017)

Research Contracts – black, Research Agreements – green 4

AUL - GU AUL - VIFM GFR – UKC

UK - OTBVTB ARG - CNEA BRA - IPEN

CHI - CCHEN COL - SDS CUB - CEADEN

IND - TMH INS - AU MAL - USM

PER - IPEN POL - WUM SLR - UNB

URU - INDT

IAEA Project Officer – Oleg Belyakov, Alternate - Eduardo

Rosenblatt, started by Jan Wondergem

Overall Objectives

Main aims of the project:

• to find the optimal radiation dose and processing methods for several tissues providing allograft sterility (SAL 10-6) without compromising tissue biological or structural function for clinical use;

• to facilitate research and disseminate research results in IAEA Member States to study radiation-induced effects on tissue grafts processed and preserved by different methods and;

• to initiate collaboration between relevant laboratories, establishing of exchange programmes and joint applications for future additional funding.

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Specific research objectives

• Study interaction between processing methods and irradiation process.

• Establish dose response relationship and validation of relevant physical, chemical, biological and clinical end-points.

• Study effect of irradiation conditions (temperature, oxygen, water content, dose rate, radio-protectants, etc.) on biological properties of tissue allografts.

• To improve tissue banking processing and preservation protocols a number of questions have been addressed.

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• 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 relation of dose-rate on physical, chemical, biological

properties of tissue allografts?

Results: bone and

demineralized bone

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• Bone: adoption of sterilization doses below 15 kGy improves tissue

quality and surgical outcomes (left panel). Higher radiation

decreases several mechanical properties of bone rings (right

panel).

• Demineralized bone (DMB): sufficient osteoinduction was observed

after experiments using DBM treated at 15 kGy radiation dose.

Courtesy Artur Kamisnski, Warsaw, Poland

Courtesy of

Sven Scheffler,

Berlin,

Germany

Results: cartilage and tendons

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Studies demonstrated that Optical Coherence Tomography (OCT) is a

suitable non-destructive technique to evaluate the changes in costal

cartilage after sterilisation by ionizing radiation. Biomechanical testing of

tendons showed decreased failure load, stiffness and AP-laxity, in the E-

beam group compared to the fresh frozen allograft group and a significant

decreased failure load compared to autograft group (P = 0.024).

Comparison of failure load, stiffness and ap-laxity

values of Ebeam, fresh frozen allograft (FFA),

autograft (Auto) and native ACL (ACL) at 6 and 12

weeks, asterisk on ACL indicates significant

difference compared to all other groups. In the

Ebeam group, stiffness and failure load decreased

from 6 to 12 weeks and AP-laxity increased. Contrary

to this, failure load increased in fresh frozen allografts

(FFA), while stiffness and AP-laxity stayed nearly

constant. In autograft group, all the aforementioned

parameters increased.

Courtesy of

Sven Scheffler,

Berlin,

Germany

Results: skin and amnion

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Most sensitive tissue to structural changes induced by radiation proved to

be animal skin, least sensitive human skin. Irradiation dose up to 25 kGy

had minor impact on the ultrastructure of the irradiated skin and its

functionality (evaporation index). In contrast to skin, morphological changes

related to the radiation dose were seen at doses of 25 kGy and up.

Surface morphology of glycerol preserved

and gamma irradiated human amnion

membrane (HAM) at magnification ×2,000,

using high vacuum scanning electron

microscopy (HVSEM); (a) Non-irradiated, (b)

15 kGy, (c) 25 kGy, (d) 35 kGy (courtesy

Suzina S. Ab Hamid, Kelatan, Malaysia).

Research Outputs

• New data on efficacy of irradiated tissue allografts for bone, tendon, cartilage, skin and amniotic membrane, vascular grafts and heart valves were obtained.

• Methodology for development of quality control testing of different types of (irradiated) tissues was formulated.

• Significant research progress in radiation sterilization and tissue banking was achieved in MSs.

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Research Outcomes

• Provision of technical expertise in processing procedures of tissues subsequently radiation-sterilized.

• Knowledge and expertise in tissue allograft irradiation was improved.

• Quality of tissue grafts was improved.

• Significant progress has been made by the participating tissue banks/institutes leading to the production of safer allografts both with respect to its functionality and sterility.

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Selected publications Suzina Sheikh Ab Hamid, Nor Kamalia Zahari, Norimah Yusof , Asnah Hassan (2014).

“Scanning electron microscopic assessment on surface morphology of preserved human

amniotic membrane after gamma sterilisation.” Cell Tissue Bank, (15):15–24.

Anna Jastrzebska , Artur Kaminski, Ewelina Grazka, Joanna Marowska, Jaroslaw Sadlo,

Grzegorz Gut, Izabela Uhrynowska-Tyszkiewicz (2013). “Effect of gamma radiation and

accelerated electron beam on stable paramagnetic centers induction in bone mineral: influence

of dose, irradiation temperature and bone defatting.” Cell Tissue Bank, electronic version.

Artur Kaminski, Ewelina Grazka , Anna Jastrzebska, Joanna Marowska, Grzegorz Gut, Artur

Wojciechowski,Izabela Uhrynowska-Tyszkiewicz (2012). “Effect of accelerated electron beam

on mechanical properties of human cortical bone: influence of different processing methods.”

Cell Tissue Bank (13):375–386.

George Morales, Astrid Lobo Gajwala (2012). “A review of the International Atomic Energy

Agency (IAEA) International Standards of Tissue banking.” Cell Tissue bank, (13): 15-25.

Peter Myint, Jan Wondergem, Yaroslav Pynda, Glyn O. Phillips (2013). “An international

survey of tissue banking, a preliminary report.” Cell Tissue Bank, (14):159- 165.

Huynh Nguyen, Alan I. Cassdy, Michael B. Bennett, Andy Wu, David A.F. Morgan, Mark R.

Forwood (2013). “Reducing the radiation sterilization dose improves mechanical and biological

quality while retaining sterility assurance levels of bone allografts.” Bone, (57):194-200.

Schmidt T, Hoburg A, Broziat C, Smith MD, Gohs U, Pruss A, Scheffler S. Cell Tissue Bank

(2012). “Sterilization with electron beam irradiation influences the biomechanical properties

and the early remodeling of tendon allografts for reconstruction of the anterior cruciate

ligament (ACL).” Cell Tissue Bank, (13): 387-400. 12

Future direction

• Tissue engineering is revolutionising medicine by shifting the

focus from addressing symptoms to repair and regeneration.

• New IAEA CRP F23030-E31007 Instructive Surfaces and

Scaffolds for Tissue Engineering Using Radiation Technology

(2014-2021) was launched to reflect this change.

• The CRP is jointly conducted by the Radioisotope Products

and Radiation Technology Section (RPRT)/Division of

Physical and Chemical Sciences (NAPC) as well as the

Applied Radiation Biology and Radiotherapy Section

(ARBR)/Division of Human Health (NAHU).

• NAPC implements the part related to the development and

testing of the instructive surfaces and scaffolds, while NAHU

implements the biomedical application part related to the end

uses. 13

Success story

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• TC project PER6017 Improving

National Capabilities to Treat

Patients with Burns, Lesions and

Polytraumatized Conditions

Through the Application of

Radiation-Processed Cells,

Scaffolds and Tissues (2014-

2017) helped to transfer skin

regeneration technology to Peru.

• 13-year patient with 80 per cent

of skin severely burnt, usually

such medical condition leads to

death.

• Thanks to the technology of skin

cultivation, doctors were able to

grow from 2 cm2 of healthy

patient's skins 2 m2 of skin to

cover wounds.

• The patient recovered in 2 month.

IAEA News Story at:

https://www.iaea.org/newscenter/news/peruvi

an-boys-life-saved-thanks-to-radiation-

technology

I would like to acknowledge Chief

Scientific Investigators of Institutions,

contributed to CRP E31006: Paulina

Maria Estela Aguirre Herrera (CHI), Dr

Emma Castro Gamero (PER), Mark

Forwood (AUS), Clara Linda Guerrero

(COL), Marisa Herson (AUS), Eulogia

Kairiyama (ARG), Artur Marek

Kaminski (POL), Astrid Ann Lobo

Gajwala (IND), Jan Koller (SLO),

Menkher Manjas (INS), Monica

Beatriz Mathor and Wilson Aparecido

Calvo (BRA), Peter Myint (UK), Isabel

Maria Otero Abreu (CUB), María del

Carmen Salidas Farinella (URU),

Suzina Sheikh Ab. Hamid (MAL),Sven

Scheffler (GFR).

Participants of the 3rd RCM of CRP E31006,

IAEA Headquarters, VIC, Vienna, Austria, 3-5

September 2014