Length dependent clearance of CNCs by macrophages. Confocal laser scanning microscopy images of the triple-cell co-culture model exposed to 0.56 ± 0.25 μg/cm2 rhodamine-labeled CNCs isolated from cotton (green
a–d) or 0.67 ± 0.09 μg/cm2 CNCs isolated from tunicates (e–h) via the ALICE system. Co-cultures were either immediately fixed (a, e) or after 1 (b, f), 24 (c, g), or 48 h (d, h) post exposure and stained for cytoskeleton (red) and nuclei (cyan). Images are presented as surface rendering (top), xz-projection of the z-stacks (middle), or twofold optical zoom (bottom). Boxes indicate digitally enlarged (×2) areas. Arrow shows fiber-F-actin interactions. Scale bars 30 μm.