Construction of Vascular Tissues via Multilayer Cell Deposition inside Hydrogel Microchannels

This paper reports a new approach for constructing blood vessel-like tissues using microfluidic devices made of calcium-containing agarose hydrogel. Sodium alginate (NaA) solutions with different cell types at high densities were introduced stepwise into the hydrogel microchannel, to deposit cell-containing multiple Ca-alginate hydrogel layers on the channel surface with the help of Ca 2+ ions diffused through the hydrogel matrix. We successfully obtained capillary-like tissues inside the hydrogel microchannel, which were then recovered from the hydrogel matrix by enzymatically digesting the agarose polymer. The presented technique would pave a new way for preparing capillary-like cell constructs for various tissue engineering applications.