title: Fully automated interpretation of ionizing radiation-induced γH2AX foci by the novel pattern recognition system AKLIDES®.
abstract: OBJECTIVE
  Assessment of phosphorylated histone H2AX (γH2AX) foci as a measure for double-strand breaks (DSB) is a common technique. Since visual interpretation is time-consuming and influenced by subjective factors, we adapted the pattern recognition algorithms of autoantibodies to automated reading of γH2AX foci.
  
  
  METHODS
  DSB formation was assessed by detection of γH2AX foci after exposition of thyreocyte rat cell line to (188)Re. We used pattern recognition algorithms of the automated fluorescence interpretation system AKLIDES(®) for evaluation of γH2AX foci. Manual investigation was performed by three laboratories involving five observers. The results were compared by determining correlation and inter-laboratory variability.
  
  
  RESULTS
  The study confirmed the adaptation of automated interpretation system AKLIDES® to automated assessment of γH2AX foci in irradiated cells. Both manual and automated quantification resulted in increasing focus numbers depending on dose. Comparison of automated reading with visual assessment for five manual observers resulted in a determination coefficient of R(2) = 0.889. The inter-laboratory variability for five manual investigators of three laboratories was 38.4 %.
  
  
  CONCLUSIONS
  The interpretation system AKLIDES(®) demonstrated a high correlation with visually observed results. High inter-laboratory variability found for manual investigations revealed the usefulness for a standardized technique for evaluation of γH2AX foci.
authors.affiliation: Department of Nuclear Medicine, Medical Faculty Carl Gustav Carus, Technische Universität Dresden. roswitha.runge@tu-dresden.de
authors.forename: Roswitha
authors.initials: R
authors.lastname: Runge
authors.forename: Rico
authors.initials: R
authors.lastname: Hiemann
authors.forename: Maria
authors.initials: M
authors.lastname: Wendisch
authors.forename: Ulla
authors.initials: U
authors.lastname: Kasten-Pisula
authors.forename: Katja
authors.initials: K
authors.lastname: Storch
authors.forename: Klaus
authors.initials: K
authors.lastname: Zöphel
authors.forename: Christina
authors.initials: C
authors.lastname: Fritz
authors.forename: Dirk
authors.initials: D
authors.lastname: Roggenbuck
authors.forename: Gerd
authors.initials: G
authors.lastname: Wunderlich
authors.forename: Karsten
authors.initials: K
authors.lastname: Conrad
authors.forename: Joerg
authors.initials: J
authors.lastname: Kotzerke
mesh_terms: D000818:Animals; D001331:Automation; D001610:Beta Particles / Q000009:adverse effects; D002460:Cell Line; D053903:DNA Breaks, Double-Stranded / Q000528:radiation effects*; D006657:Histones / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods*; D051381:Rats; D013961:Thyroid Gland / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects
chemical_list: C468783:H2AX protein, human; D006657:Histones