Fig. 5: ECs grew vertically at communication pores to form a leakage-free seal between the microvascular networks and medium channels.

a Schematic drawings of vertical anastomosis at the communication pores show that the ECs sealed the inner walls and formed connections. b Time-lapsed images clearly show that the ECs grew at the communication pores and formed connections. c Different images demonstrating the connections between the upper and lower layers. d Confocal images showing the full connections and how the culture medium flows though these connections into the capillaries