Reproducibility of scratch assays is affected by the initial degree of confluence: experiments, modelling and model selection

Wang Jin, Esha T. Shah, Catherine J. Penington, Scott W. McCue, Lisa K. Chopin, Matthew J. Simpson

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Scratch assays are difficult to reproduce. Here we identify a previously overlooked source of variability which could partially explain this difficulty. We analyse a suite of scratch assays in which we vary the initial degree of confluence (initial cell density). Our results indicate that the rate of re-colonisation is very sensitive to the initial density. To quantify the relative roles of cell migration and proliferation, we calibrate the solution of the Fisher-Kolmogorov model to cell density profiles to provide estimates of the cell diffusivity, D, and the cell proliferation rate, lambda. This procedure indicates that the estimates of D and A are very sensitive to the initial density. This dependence suggests that the Fisher-Kolmogorov model does not accurately represent the details of the collective cell spreading process, since this model assumes that D and lambda are constants that ought to be independent of the initial density. Since higher initial cell density leads to enhanced spreading, we also calibrate the solution of the Porous-Fisher model to the data as this model assumes that the cell flux is an increasing function of the cell density. Estimates of D and lambda associated with the Porous-Fisher model are less sensitive to the initial density, suggesting that the Porous-Fisher model provides a better description of the experiments. (C) 2015 Elsevier Ltd. All rights reserved.

LanguageEnglish
Pages136-145
Number of pages10
JournalJournal of Theoretical Biology
Volume390
DOIs
Publication statusPublished - 7 Feb 2016
Externally publishedYes

Keywords

  • Scratch assay
  • Reproducibility
  • Cell diffusivity
  • Cell proliferationrate
  • Cell proliferation rate

Cite this

Jin, Wang ; Shah, Esha T. ; Penington, Catherine J. ; McCue, Scott W. ; Chopin, Lisa K. ; Simpson, Matthew J. / Reproducibility of scratch assays is affected by the initial degree of confluence : experiments, modelling and model selection. In: Journal of Theoretical Biology. 2016 ; Vol. 390. pp. 136-145.
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Reproducibility of scratch assays is affected by the initial degree of confluence : experiments, modelling and model selection. / Jin, Wang; Shah, Esha T.; Penington, Catherine J.; McCue, Scott W.; Chopin, Lisa K.; Simpson, Matthew J.

In: Journal of Theoretical Biology, Vol. 390, 07.02.2016, p. 136-145.

Research output: Contribution to journalArticleResearchpeer-review

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