The development of cryopreservation techniques for fabrication of scaffold-free tissue construct by bio-3D printing

Abstract

We have established a system for assembling scaffold-free cell constructs, through the development of an automated 3D bio-printer, which can fabricate 3D cell constructs such as liver, cartilage or blood vessels. Our next challenges were to prepare a lot of spheroids for clinical application and to develop cryopreservation techniques so that spheroids can be transported and preserved for long periods of time. In this study, we have cryopreserved spheroids by using commercially available cryopreservation solution.Preliminary studies consisted of freezing spheroids of various sizes of human dermal fibroblast for 1 week. Spheroids cryopreserved in PBS solution were not fused with each other, whereas spheroids in cryopreserved solution were started to fuse at 5days. And the improvement of cryopreserved method has reduced the fusion time from 5 to 3 days. In conclusion, it was suggested that spheroids can be frozen and used by improvement of cryopreserved method.