Position-based Dynamics for Multicellular Systems with Adhesion MemorySteffen PlunderKyoto UniversityInstitute for the Advanced Study of Human BiologyACMB-JSMB2025Minisymposium MS08
ContentsModelling of Plithotaxis via adhesion memoryEffect of realistic repolarisation delaysPosition-based Dynamics (PBD)Motivation: What happens after EMT?Modelling: The challenge of syncronisation with polarisation delaysMathematics: Numerical method (outlook)A Volterra-equation for adhesive memoryExtension of PBD for an integral equation
Movivation: What happens after epithelial-to-mesenchymal transitions?EMT: cells change from stable/skin-like phenotype to migratory phenotype (e.g. migrating cancer cells)
Movivation: What happens after epithelial-to-mesenchymal transitions?PhD: Modelling of EMT in...Neural Crest(Embryogenesis)SP, Cathy Danesin, Bruno Glise, Marina A. Ferreira, Sara Merino-Aceituno, and Eric Theveneau. “Modelling Variability and Heterogeneity of EMT Scenarios Highlights Nuclear Positioning and Protrusions as Main Drivers of Extrusion.” Nature Communications, 2024Mouse Primitive Streak(Gastrulation)Despin-Guitard, Evangéline, Viviane S. Rosa, Steffen Plunder, Navrita Mathiah, Kristof Van Schoor, Eliana Nehme, Sara Merino-Aceituno, et al. “Non-Apical Mitoses Contribute to Cell Delamination during Mouse Gastrulation.” Nature Communications 2024Drosophila Eye-Antenna(Oncogenesis)Mira-Osuna, Marta, SP, Eric Theveneau, and Roland Le Borgne. “The Directionality of Collective Cell Delamination Is Governed by Tissue Architecture and Cell Adhesion in a Drosophila Carcinoma Model.” bioRxiv, 2024
Movivation: What happens after epithelial-to-mesenchymal transitions?How do the cells migrate through the basal matrix?Extracellular Matrix:- dense network of collagen fibersKnown mechanisms:- cell can degrade the basal matrix- migration through created gaps in small to large groups
Part I
First approach: Obstacle modelMany difficult modellingquestions:- how do single cells move?- how do pairs of cells move?- behaviour in clusters?Too complex!
Foundations of cellular motion
Agent-based Modelbias?see talk by Antoine Diez 11th (Friday), 10:10am, Room 6cell-cell adhesioncell-matrix adhesion polarity dynamics Focus today:Different polarity dynamics!
(n = 1) Individual cell dynamics: Run & TumbleChange polarity after (randomized) time-intervals:
(n = 2) Pairwise interactions: Contact Inhibition of LocomotionCIL: ~cells collide, stick together for a while and repolarize (from a random rice field in Nara)
(n = 2) Pairwise interactions: Contact Inhibition of LocomotionScarpa, Elena, Alice Roycroft, Eric Theveneau, Emmanuel Terriac, Matthieu Piel, and Roberto Mayor. “A Novel Method to Study Contact Inhibition of Locomotion Using Micropatterned Substrates.” Biology Open, 2013Key biological aspectfor our model:The time of collision is slow,aorund 5 minutes!
(n = 2) Pairwise interactions: Contact Inhibition of Locomotionhard radiussoft radiusCell-cellcontact model
(n = 2) Pairwise interactions: Contact Inhibition of LocomotionIn our model, CIL affects first the set of adhesive bonds!set of adhesive bonds...then wechange the polarity vector
(n = 2) Pairwise interactions: Contact Inhibition of Locomotion
Note:Most parameters so far are inverable from videos!
Question: Is this enough for collective migration?Woods, Mae L., Carlos Carmona-Fontaine, Chris P. Barnes, Iain D. Couzin, Roberto Mayor, and Karen M. Page. “Directional Collective Cell Migration Emerges as a Property of Cell Interactions.” PLOS ONE, 2014Yes!We can replicate their model!But it fails once we imposerealistic CIL duration!Takeaway: Repolarisation duration / adhesion memory shows that something is missing for collective cell migration!
(n > 2) Behaviour in clustersPossible mechanisms of migration:Chemotaxis / Durotaxis / Haptotaxis / Mechanotaxis / ...(it's a large field)Buttenschön, Andreas, and Leah Edelstein-Keshet. “Bridging from Single to Collective Cell Migration: A Review of Models and Links to Experiments.” PLOS Computational Biology, 2020
Our pick: PlithotaxisTrepat, Xavier, and Jeffrey J. Fredberg. “Plithotaxis and Emergent Dynamics in Collective Cellular Migration.” Trends in Cell Biology 21, no. 11 (November 1, 2011)The collective tendency for each cell comprising the sheet to steer along the local orientation of maximal principal intercellular stress, or, equivalently, minimal intercellular shear stress, is called plithotaxissource: WikiData
(n > 2) Adhesive memory + PlithotaxisDynamic creating and breakage of bondsForce dependent duration of stable protrusionsDynamic waiting times:
Overview
Movies (see https://steffenpl.github.io/research/projects/cell-migration-model/)
Force gradient controlsrepolarisation speedA chaotic but robuts model for self-organisation
Benchmark(s):Confinement is a requirement for self-organisation
ConclusionAdding realistic repolarisation delays (CIL: 5min, Plithotaxis: ~10 - 45min) affects the ability for collective migration.Our model recapitulates appearance of stress gradientand common behaviour (need for convienment, group speeds fits experimental data, ...)Future plans: Experimental evidence by inhibiting cell's ability tosense mechanical stress / increase duration of repolarisation.
a short break...math incoming in 3... 2... 1...
Part IINumerics for non-overlap...an easy methodfor situations like this...a veryyy short introduction on simulation with inequality constraints
The idea behind Position-based Dynamics (PBD) ODEs with inequality constraints: Possible numerical discretisation (Moreau's sweeping process): SKey insight: Projection errors (for non-convex sets) are not linear in the distance to a set!
First-order PBD convergesInstead of (expensive)iterative methodfor projection: Pairwise non-overlapPBD: SP, and Sara Merino-Aceituno. “Convergence Proof for First-Order Position-Based Dynamics: An Efficient Scheme for Inequality Constrained ODEs.” arXiv, 2023computational costConsistency (in a susc sense) + stability = convergence.Thm. (SP, Sara Merino, arxiv, 2023)
Thm. (SP, Sara Merino, arxiv, 2023) The full theorem is a bit technical...
Other modelsBacteria model from Michéle Romanos Anisotropic repulsion from Claudia Wytrzens, Sara Merino-Aceituno Neural tubewith Eric Theveneau, Sara Merino-Aceituno
ConclusionSatisfying inequality conditions infirst-order dynamical systems is not that hard!SKey insight: Projection errors (for non-convex sets) are not linear in the distance to a set!
Next steps: Application of PBD to Volterra-type integral equationRepolarisation (during CIL and in clusters) depends on existing cytoskeleton and cell-matrix adhesionmatrix attachment location (from the past)current position
Next steps: Application of PBD to Volterra-type integral equationmatrix Going multicellular: Introduce non-overlapPBD-style
Thank you!CollaboratorsSara Merino-AceitunoEric TheveneauVuk Milisic+ many coauthors, colleagues and friendsFunding 22H05110 (PI: Seirin Lee)Grant-in-Aid for Transformative Research Areas (A)JP24K16962 (PI: SP)Grant-in-Aid for Early-Career ScientistsWWTF (Vienna Science and Technology Fund)