Tissue flow acts as a guidance cue for immune cell polarization and directional migration.

Tissue flows guide embryonic myeloid cell polarization and directional migration in Xenopus embryos, with disruption impairing cell dispersion.

• Why it matters: Understanding how immune cells navigate through tissues during early development is crucial for insights into immune system formation and tissue organization, yet the guiding mechanisms remain unclear.
• What they did: The study established an ex vivo live imaging and manipulation system to analyze EM cell migration, revealing that local ectodermal tissue flows repolarize cell protrusions and bias migration, with disruption impairing dispersion.
• The result: Mechanical cues from tissue flows coordinate immune-cell migration, suggesting an overlooked mechanism by which collective tissue dynamics influence individual immune cell behavior during development.