Modelling Cell Attachment

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Modelling Cell Attachment

• Jonathan A. Ratcliffe

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Outline

• Aims
• Theory
• Imaging
• Image Processing
• Comparison to SEM
• Conclusions
• Future work

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Aims

• To visualise a cell as it undergoes the
  transition from attaching and spreading to
  crawling
• To create an accurate three-dimensional
  representation of the cell so that predictions
  can be made about spreading using the dynamic
  contact line of the cell.

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• The dynamic contact angle

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• 2 stages of cell spreading Passive and Active

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Theory
Network density at contact line
Mass transfer rate from G- to F- actin at contact
line
Dynamic Contact angle (to be determined)

• J. Oliver, et al. Thin-film theories for
  two-phase reactive flow models of active cell
  motion Mathematical Medicine and Biology (2005)
  22, 5398

Fluid forces
Motile machinery
Static contact angle
Outward normal velocity for contact line.
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Imaging

• LavaCell stain chosen as
• Cost effective
• Simple to use, add 1.8µl for 1.5ml media
• Long stokes shift (fluorescence lifetime)
• No cytotoxicity observed up to 24h.
• Best images

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Image Processing
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Image Prossesing
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• Cell imaged at 20 minutes after seeding.

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• Cell imaged 60 minutes after seeding.

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• Human Osteosarcoma cell 70 minutes after seeding.

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Conclusions

• Image processing technique accurately finds
  outline of cell segments.
• 3D representations visually similar to SEM images
  of fixed cells.

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Future Work

• To look at transparent coated surfaces such as
  TiN, TiO2, Gold, SS 316L.
• Patterned surfaces
• Surface topography using embossed glass