Reconstruction of vascular structure with multicellular components using cell transfer printing methods.

Natural vessel has three types of concentric cell layers that perform their specific functions. Here, the fabrication of vascular structure is reported by transfer printing of three different cell layers using thermosensitive hydrogels. Tetronic-tyramine and RGD peptide are co-crosslinked to prepare cell adhesive and thermosensitive hydrogels. The hydrogel increases its diameter by 1.26 times when the temperature reduces from 37 °C to 4 °C. At optimized seeding density, three types of cells form monolayers on the hydrogel, which is then transferred to the target surface within 3 min. Three monolayers are simultaneously transferred on one substrate with controlled shape and arrangement. The same approach is applied onto nanofiber scaffolds that are cultured for more than 5 d. Every type of monolayer shows proliferation and migration on nanofiber scaffolds, and the formation of robust cell-cell contact is revealed by CD31 staining in endothelial cell layer. A vascular structure with multicellular components is fabricated by transfer of three monolayers on nanofibers that are manually rolled with the diameter and length of the tube being approximately 3 mm and 12 mm, respectively. Collectively, it is concluded that the tissue transfer printing is a useful tool for constructing a vascular structure and mimicking natural structure of different types of tissues.