Integer topological defects offer a methodology to quantify and classify active cell monolayers.

ABSTRACT: Monolayers of confluent elongated cells are frequently considered active nematics, featuring ±12 topological defects. In extensile systems, where cells extend further along their long axis, they can accumulate at +12 defects and escape from -12 defects. Nevertheless, collective dynamics surrounding integer defects remain insufficiently understood. We induce diverse  + 1 topological defects (asters, spirals, and targets) within neural progenitor cell monolayers using microfabricated patterns. Remarkably, cells migrate toward the cores of all  + 1 defects, challenging existing theories and conventional extensile/contractile dichotomy, which predicts escape from highly bent spirals and targets. By combining experiments and a continuum theory derived from a cell-level model, we identify previo

SUBMITTER: Zhao Z 

PROVIDER: S-EPMC11897356 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature