The second gamma-H2AX assay inter-comparison exercise carried out in the framework of the European biodosimetry network (RENEB).
Within the EU RENEB project, seven laboratories have taken part in training and harmonisation activities to strengthen triage gamma-H2AX-based radiation exposure assessment. This has culminated in a second triage biodosimetry exercise.



Whole blood and separated lymphocyte samples were homogenously irradiated with60Co gamma rays at 0.5, 2.5 (blind samples), 0 and 2 Gy (reference samples). Following post-exposure incubations of 4 and 24 h, 16 samples were shipped on ice packs to each partner. The samples were stained and scored for gamma-H2AX foci, using manual and/or automated fluorescence microscope scoring strategies. Dose estimates were obtained and used to assign triage categories to the samples.



Average dose estimates across all the laboratories correlated well with true doses. The most accurate assignment of triage category was achieved by manual scoring of the 4-h blood and lymphocyte samples. Only three samples out of a total of 46 were miscategorized in a way that could have adversely effected the clinical management of a radiation casualty.



This inter-comparison exercise has demonstrated that following a recent acute radiation exposure, the gamma-H2AX assay could be a useful triage tool that can be successfully applied across a network of laboratories.
a Public Health England, Centre for Radiation Chemical and Environmental Hazards , Chilton , UK.
Jayne
J
Moquet
a Public Health England, Centre for Radiation Chemical and Environmental Hazards , Chilton , UK.
Stephen
S
Barnard
b National Centre of Radiobiology and Radiation Protection , Sofia , Bulgaria.
Albena
A
Staynova
c Radiation and Nuclear Safety Authority (STUK) , Helsinki , Finland.
Carita
C
Lindholm
d Instituto Superior Técnico, Universidade de Lisboa, C2TN, Bobadela-LRS , Portugal.
Octávia
O
Monteiro Gil
d Instituto Superior Técnico, Universidade de Lisboa, C2TN, Bobadela-LRS , Portugal.
Vanda
V
Martins
e Bundesamt für Strahlenschutz , Oberschleissheim , Germany.
Ute
U
Rößler
f Department of Basic Medical Sciences , Ghent University , Ghent , Belgium.
Anne
A
Vral
f Department of Basic Medical Sciences , Ghent University , Ghent , Belgium.|g Themba LABS, National Research Foundation , Somerset West , South Africa.
Charlot
C
Vandevoorde
h Institute of Nuclear Chemistry and Technology, Centre for Radiobiology and Biological Dosimetry , Warsaw , Poland.
Maria
M
Wojewódzka
a Public Health England, Centre for Radiation Chemical and Environmental Hazards , Chilton , UK.|i Department of Radiotherapy & Radio-Oncology , University Medical Centre Hamburg-Eppendorf , Hamburg , Germany.
Kai
K
Rothkamm
D001681:Biological Assay / Q000379:methods* / Q000592:standards; D002869:Chromosome Aberrations / Q000528:radiation effects*; D004249:DNA Damage / Q000235:genetics*; D005060:Europe; D005720:Gamma Rays; D006657:Histones / Q000235:genetics; D006801:Humans; D008214:Lymphocytes / Q000502:physiology / Q000528:radiation effects; D011785:Quality Assurance, Health Care; D000069079:Radiation Exposure / Q000032:analysis*; D011834:Radiation Monitoring / Q000379:methods* / Q000592:standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
C468783:H2AX protein, human; D006657:Histones
RENEB; biological dosimetry; gamma-H2AX assay; radiation-induced foci; triage