Radiation and Environmental Biophysics

, Volume 55, Issue 2, pp 185–194 | Cite as

An evaluation of novel real-time technology as a tool for measurement of radiobiological and radiation-induced bystander effects

  • Mohammad Johari Ibahim
  • Jeffrey C. Crosbie
  • Premila Paiva
  • Yuqing Yang
  • Marina Zaitseva
  • Peter A. W. RogersEmail author
Original Article


The xCELLigence real-time cell impedance system uses a non-invasive and label-free method to create a cell index that is a composite measure of cell proliferation. The aim of this study was to evaluate xCELLigence against clonogenic assay (gold standard) for measuring radiobiological effects and radiation-induced bystander effects (RIBE). A radiobiological study was conducted by irradiating EMT6.5, 4T1.2 and NMUMG cell lines with different radiation doses, while a RIBE study was done using transfer of conditioned media (CM) harvested from donor to the same type of recipient cell (EMT6.5, 4T1.2, NMUMG, HACAT and SW48). CM was harvested using two protocols which differed in the dose chosen and the exposure to the recipient cells. Results showed that xCELLigence measured a radiobiological effect which correlated with the clonogenic assay. For the RIBE study, no statistically significant differences were observed between xCELLigence or clonogenic survival in control or recipient cells incubated with CM in protocol one. However, there was a significant increase in cell index slope using CM from EMT-6.5 cells irradiated at 7.5 Gy compared with the control group under the second protocol. No other evidence of RIBE was detected by either xCELLigence or clonogenic assay. In conclusion, xCELLigence methods can measure radiobiological effects and the results correlate with clonogenic assay. We observed a lack of RIBE in all tested cell lines with the clonogenic assay; however, we observed a RIBE effect in EMT6.5 cells under one particular protocol that showed RIBE is cell type dependent, is not universally observed and can be detected in different assays.


Radiotherapy Bystander effects Clonogenic assay xCELLigence RT-CIS 



The study was funded in part by a Project Grant (606614) from the National Health & Medical Research Council (NHMRC), Australia.

Compliance with ethical standards

Conflict of interest

All authors declare no conflicts of interest. Premila Paiva and Jeffrey C. Crosbie are recipients of Early Career Researcher Fellowships from the National Health & Medical Research Council (NHMRC), Australia. Mohammad Johari Ibahim receives PhD scholarship from The Ministry of Higher Education, Malaysia.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Supplementary material

411_2016_641_MOESM1_ESM.docx (2.9 mb)
Supplementary material 1 (DOCX 2979 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Mohammad Johari Ibahim
    • 1
    • 2
  • Jeffrey C. Crosbie
    • 3
    • 4
  • Premila Paiva
    • 1
  • Yuqing Yang
    • 1
  • Marina Zaitseva
    • 1
  • Peter A. W. Rogers
    • 1
    Email author
  1. 1.Department of Obstetrics and Gynaecology, Royal Women’s HospitalUniversity of MelbourneParkvilleAustralia
  2. 2.Faculty of MedicineUniversiti Teknologi MARA, Sungai Buloh Campus, Jalan HospitalSungai BulohMalaysia
  3. 3.School of Applied SciencesRMIT UniversityMelbourneAustralia
  4. 4.William Buckland Radiotherapy CentreAlfred HospitalMelbourneAustralia

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