Counting clonogenic assays from normoxic and anoxic irradiation experiments manually or by using densitometric...

Area of Science:

• Oncology
• Radiation Biology
• Cell Biology

Background:

• The clonogenic assay is crucial for assessing cell reproductive death after in vitro irradiation.
• Manual colony counting is laborious, time-consuming, and subjective.

Purpose of the Study:

• To compare manual colony counting with automated counting using the ClonoCounter program.
• To evaluate the reliability of ClonoCounter for human tumor cell colony quantification in radiobiology experiments.

Main Methods:

• Five human tumor cell lines were irradiated under normoxia and anoxia.
• Colonies were counted manually by two investigators and automatically using ClonoCounter software.
• Radiobiological parameters were analyzed to compare counting methods.

Main Results:

• A positive correlation was observed between manual and automated colony counts.
• ClonoCounter showed a trend of underpredicting absolute colony numbers.
• No significant differences in survival curves or key radiobiological parameters were detected between methods.

Conclusions:

• The freely available ClonoCounter program demonstrates sufficient reliability for automated colony counting in in vitro irradiation experiments.
• ClonoCounter offers a cost-effective and objective alternative to manual counting, with minimal instrument costs.
• This tool can enhance efficiency and objectivity in radiobiological research.