Microchannel

About the Model

For details about the model, we refer to the paper. Alternatively, you can check out the following online, interactive explorables to learn more about Cellular Potts Models in general or the Act-CPM, specifically (Wortel and Textor, 2020).

Suggestions

Try the following:

• Set λ_act or max_act to 0. You should see that the cell cannot break symmetry and form stable protrusions to migrate.
• Set λ_act back to 500 and max_act to a very high value, e.g. 1000. Click "reseed cell". You should see that the cell again has a hard time breaking symmetry, this time because the activity is high everywhere (and thus, there is no polarity gradient).
• Refresh the page to go back to the default settings, and watch the cell for a while. Click "reseed cell" a couple of times. You should see that sometimes the cell manages to break symmetry and move persistently, while other times it takes longer because multiple protrusions form and compete.
• Strengthen the protrusive force ΔH_act by increasing λ_act. You should see that the cell moves faster.
• Decrease λ_act to 100. You should see that the protrusion becomes smaller, the cell moves more slowly and stops/turns often. The protrusion also frequently "shifts" up and down even if it stays on the same side of the cell.
• At this low λ_act setting, now increase max_act to 100. You should see that the activity gradient reaches farther into the cell, stabilizing the protrusion and allowing persistent motion.

References