biostudies-literaturePaulson SGU.S. Department of DefenseCosmos Club FoundationNational Institutes of HealthUniformed Services UniversityNIH HHSNIGMS NIH HHSUniformed Services University of the Health Sciencesbio062021https://www.ebi.ac.uk/biostudies/studies/S-EPMC12486203biostudies-literatureUnknown14(9)Physical confinement is not routinely considered as a factor that influences phagocytosis, which is typically investigated using unconfined in vitro assays. BV2 microglia-like cells were used to interrogate the impact of confinement on IgG-mediated phagocytosis side by side with unconfined cells. Confinement acted as a potent phagocytic driver, greatly increasing the fraction of phagocytic cells in the population compared to the unconfined setting. Arp2/3 complex and myosin II contributed to this effect. Remarkably, confinement partially rescued phagocytic uptake upon myosin II disruption. In addition, cells under confinement were partially resistant to the actin-depolymerizing drug cytochalasin D. Unexpectedly, we observed that bead uptake stimulated persistent migration, a process we terBiology openPhysical confinement and phagocytic uptake induce persistent cell migration.PMC12486203HU00012320103R01 GM134104Department of DefenseGM134104Liu SPaulson SGRotty JDfalsePhysical confinement and phagocytic uptake induce persistent cell migration.Physical confinement is not routinely considered as a factor that influences phagocytosis, which is typically investigated using unconfined in vitro assays. BV2 microglia-like cells were used to interrogate the impact of confinement on IgG-mediated phagocytosis side by side with unconfined cells. Confinement acted as a potent phagocytic driver, greatly increasing the fraction of phagocytic cells in the population compared to the unconfined setting. Arp2/3 complex and myosin II contributed to this effect. Remarkably, confinement partially rescued phagocytic uptake upon myosin II disruption. In addition, cells under confinement were partially resistant to the actin-depolymerizing drug cytochalasin D. Unexpectedly, we observed that bead uptake stimulated persistent migration, a process we ter2025-01-01T00:00:00Z2025 Sep2026-07-15T06:49:23.919Z2026-06-30T03:23:51.082ZS-EPMC124862034088872810.1242/bio.062021