A new understanding of cell motility enabled by a microfluidic in vitro model
Wilson KA., Lewalle ARM., Fritzsche M., Duke T., Charras GT.
Microfluidic devices modified from Irimia and coworkers  combined with confocal microscopy have allowed the realtime interrogation of neutrophil-like HL60 cell migration in response to chemotactic gradients in confined microchannels. Morphometric analysis combined with fluorescence recovery after photobleaching (FRAP) experiments show complex distribution and flow dynamics of actin at the leading edge. These results suggest that two gels of actin are polymerized in the front of neutrophils migrating in microfluidic channels: one at the leading edge and one at the cell-wall interface. These gels interact to create a wedge that results in the protrusion of the leading edge and hence forward movement.