The research team led by professor Geun HyungKim in the biomechatronic engineering department developed a “Pri-Actor”bioprinting system named via coupling bioprinter with in situ bioreactorwhich can effectively induce myogenesis to the host cell. The term “Pri-actor”is an amalgamation of printer and bioreactor. 

Figure 1. Schematical diagram of “Pri-Actor” system.

The Pri-Actor system utilizes simultaneous in situ supplementation of physical force (electric field & UV radiation) during the extrusion process of human Adipose Stem Cells (hASCs)-ladened bioink. Subsequentially, a significantly higher degree of cell proliferation and myogenesis was observed with the Pri-Actor printing system. During the short supplementation of electric field (~0.1 s) various printing parameters have been optimized for the optimum degree of myogenic related signaling pathways and activation of ion voltage channels, as well as cellular alignment and effective formation of myotubes.

The bio-construct printed via the Pri-Actor system were further analyzed in volumetric muscle defect in the animal model (rat). As result, functional muscle formation with vascular and nervous networks was observed. In addition, the physical analysis revealed that muscle functionality was fully recovered to pre-defect levels. Professor Geun Hyung Kim has stated “Based on the promising results, the Pri-Actor system can effectively mimic the native anatomical structures of muscle, as well as fully restoring the functionality of muscle”

Figure 2. schematical diagram of in situ “Pri-Actorsystem” and histological staining of isolated trabecular muscle 8 weeks afterimplantation.

Professor Geun Hyung Kim has stated, “Based onthe promising results, the Pri-Actor system can effectively mimic the nativeanatomical structures of muscle, as well as fully restoring the functionalityof muscle”. In addition, he has stated “By controlling the physical stimulationincorporated in the current system can effectively target various oforgans/tissues in the human body. Additionally, further development of the Pri-Actorsystem can expand its potential into a personalized fabrication system forvarious tissues and organs. 

This study was supported by an NRF grant fundedby the Ministry of Science and ICT for the Bioinspired Innovation TechnologyDevelopment Project. In addition, these studies were published in “AdvancedFunctional Materials” (Impact factor = 18.8) on 2021/08, “Bioactive materials”(Impact factor = 14.6) on 2021/07, and “Chemical Engineering Journal (Impactfactor = 13.3) on 2021/04. Furthermore, these studies were featured in ArirangTV BizTech Korea “Outlook for regenerative medicine” on 2021/08/04

※Papertitle: A Bioprinting Process Supplemented with In Situ Electrical StimulationDirectly Induces Significant Myotube Formation and Myogenesis. (AdvancedFunctional Materials)

※ Paper title: Bio-printing of aligned GelMa-basedcell-laden structure for muscle tissue regeneration. (Bioactive Materials)

※ Paper title: Bioprinted hASC-laden structures withcell-differentiation niches for muscle regeneration. (Chemical EngineeringJournal)

※Arirang TV: https://www.youtube.com/watch?v=VsgMBgr3EwU