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

Tissue flows guide immune cell polarization and migration, with local ectodermal flows directing embryonic myeloid cell dispersion in Xenopus embryos.

• Why it matters: Understanding how immune cells navigate through tissues during early development is crucial for insights into immune system formation and tissue repair mechanisms, yet this process remains poorly understood.
• What they did: The study developed an ex vivo migration system combining live imaging, computational analysis, and optogenetics to investigate EM cell movement, revealing that tissue flows influence cell polarization and directionality.
• The result: Disruption of tissue flows impairs EM cell dispersion, demonstrating that mechanical cues from tissue dynamics are essential for guiding immune cell migration during embryogenesis.