Symposium SB02: Emerging Nanotechnologies for Cellular Interrogation and Manipulation

Chwee Teck Lim, National University of Singapore

Micro and Nanomechanical Cues in Driving Collective Cell Migration

Written by Grace Hu

An essential process involved in wound healing and cancer formation, collective cell migration is a complex dance to the music of both biochemical and physical cues. Chwee Teck Lim weaves through an extensive set of projects his laboratory has undertaken to try and probe deeper into this phenomenon. In the first study, the researchers performed micro-contact printing of fibronectin patterns to create strips of varying thickness (20-400 µm), to which they observed how MDCK cells migrated on the fibronectin. By examining particle image velocimetry (PIV) analyses of the time lapse, cells on the wider strips showed more swirling motion while those in thinner channels exhibited more directed and coordinated movements as they were constrained by the boundaries. Treating cells with blebbistatin to inhibit actomyosin contractility then blocked the swirling, vortex-like motion, which highlights the importance of this protein complex in migratory processes.

Next, Lim performed a study to compare migration behavior of MDCK with HaCaT (human epidermal keratinocytes behavior), where the latter migrated as a uniformly integrated cell sheet instead of discrete groups. From a tissue fluidity standpoint, given the fact that cell-cell rearrangement was observed more in MDCK cells than in keratinocytes, cell phenotypes indeed matter for different applications. Lastly, Lim showed results about how adherens junctions are needed to initiate cell rotation, topological defects in epithelia govern cell death and extrusion, and how imposing tubular constraints can provide more three-dimensional insights regarding migration into microtubules.

As for what’s next? More experimental assays to examine curvotaxis, and he closes off his talk reminiscing about Hawaii’s great surfing scene by showing how cells can surf waves too (or in their case, traverse positive and negative curvatures) – pretty groovy if you ask me!