Fig. 1

Representative confocal microscopy images of TNTs in the developing human telencephalon at 18 wg. a, c Fibronectin (FN) staining reveals the basal lamina of cerebral cortex microvessels and FN⁺ TNTs (arrows). b, d On the single FN channel (green) the FN⁺ TNT in (b) appears interrupted (arrows), while in d a long and fine FN⁺ TNT (arrows) bridges the gap between two distant vessels. Nuclear counterstaining propidium iodide (PI). Scale bars a–d 25 µm