Toward complete laser ablation of melanoma contaminant cells in a co-culture outgrowth model via image cytometry

Cytometry A. 2006 Jul;69(7):573-81. doi: 10.1002/cyto.a.20290.


Background: Contaminant cancer cells in autologous transplant tissue can cause relapse and the rates are unknown. A method capable of removing all contaminant cells with a high probability detected by cytomic analyses would be useful. Neither 100% cell purging nor techniques for measuring the probability of success have been developed. Here, we report a method for removing 100% of the cells under ideal staining conditions and quantify the probability of success.

Methods: Laser ablation was combined with previously reported automated microscopy to purge contaminant cells and evaluate 100% ablation in a co-culture model of prestained mouse melanoma cells mixed with mouse NIH-3T3 cells. Melanoma passage efficiency was measured by: (1) micropipetting single cells into microtiter wells and (2) ablating all but one melanoma cell in co-cultures.

Results: (74 +/- 5)% of single melanoma cells pipetted into microtiter plate wells divided at least once. With ablation of all but one contaminant cell in co-cultures, melanoma dominated in (62 +/- 8)% cultures in 21 days. With 100% ablation in six additional experiments, no melanoma outgrowth was observed, giving a >99.1% probability that all contaminant melanoma cells were purged.

Conclusions: We successfully demonstrated a model for complete ablation within a defined probability using automated high-content image cytometry with ideal staining conditions. The results show that the instrumentation is capable of delivering 100% ablation at a defined probability and establishes the basis for further studies with clinical models wherein pretherapeutic cytomic analyses of unique cellular expression and/or morphological characteristics will be key for contaminant cancer cell identification.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Proliferation
  • Clone Cells
  • Coculture Techniques / instrumentation
  • Coculture Techniques / methods
  • Fluorescent Dyes
  • Image Cytometry / instrumentation*
  • Image Cytometry / methods*
  • Lasers*
  • Melanins / metabolism
  • Melanoma, Experimental / metabolism
  • Melanoma, Experimental / pathology*
  • Mice
  • NIH 3T3 Cells


  • Fluorescent Dyes
  • Melanins