Macrophages were first identified in transparent starfish larvae (Astropecten pentacanthus) more than a century ago, so it is fitting that a new function for macrophages would again be discovered in transparent marine larvae, this time from zebra fish (Danio rerio). On page 1317 of this issue, Eom and Parichy (1) reveal a wholly unexpected tissue-specific function of macrophages—their cardinal role in long-distance communication between nonimmune cells. In doing so, macrophages choreograph the patterning of pigment cells that eventually form the stripes on zebrafish.
Author: Martin Guilliams