title: An Innovative Collagen-Based Cell-Printing Method for Obtaining Human Adipose Stem Cell-Laden Structures Consisting of Core-Sheath Structures for Tissue Engineering.
abstract: Three-dimensional (3D) cell printing processes have been used widely in various tissue engineering applications due to the efficient embedding of living cells in appropriately designed micro- or macro-structures. However, there are several issues to overcome, such as the limited choice of bioinks and tailor-made fabricating strategies. Here, we suggest a new, innovative cell-printing process, supplemented with a core-sheath nozzle and an aerosol cross-linking method, to obtain multilayered cell-laden mesh structure and a newly considered collagen-based cell-laden bioink. To obtain a mechanically and biologically enhanced cell-laden structure, we used collagen-bioink in the core region, and also used pure alginate in the sheath region to protect the cells in the collagen during the printing and cross-linking process and support the 3D cell-laden mesh structure. To achieve the most appropriate conditions for fabricating cell-embedded cylindrical core-sheath struts, various processing conditions, including weight fractions of the cross-linking agent and pneumatic pressure in the core region, were tested. The fabricated 3D MG63-laden mesh structure showed significantly higher cell viability (92 ± 3%) compared with that (83 ± 4%) of the control, obtained using a general alginate-based cell-printing process. To expand the feasibility to stem cell-embedded structures, we fabricated a cell-laden mesh structure consisting of core (cell-laden collagen)/sheath (pure alginate) using human adipose stem cells (hASCs). Using the selected processing conditions, we could achieve a stable 3D hASC-laden mesh structure. The fabricated cell-laden 3D core-sheath structure exhibited outstanding cell viability (91%) compared to that (83%) of an alginate-based hASC-laden mesh structure (control), and more efficient hepatogenic differentiations (albumin: ∼ 1.7-fold, TDO-2: ∼ 7.6-fold) were observed versus the control. The selection of collagen-bioink and the new printing strategy could lead to an efficient way to achieve 3D cell-laden mesh structures that mimic the anatomical architecture of a patient's defective region.
authors.affiliation: Department of Biomechatronic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU) , Suwon 440-746, South Korea.
authors.forename: MyungGu
authors.initials: M
authors.lastname: Yeo
authors.affiliation: Department of Surgery, Hangang Sacred Heart Hospital, College of Medicine, Hallym University , Seoul 445-907, South Korea.
authors.forename: Ji-Seon
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Surgery, Hangang Sacred Heart Hospital, College of Medicine, Hallym University , Seoul 445-907, South Korea.
authors.forename: Wook
authors.initials: W
authors.lastname: Chun
authors.affiliation: Department of Biomechatronic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU) , Suwon 440-746, South Korea.
authors.forename: Geun Hyung
authors.initials: GH
authors.lastname: Kim
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000464:Alginates / Q000737:chemistry; D002470:Cell Survival; D003094:Collagen / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D066330:Printing, Three-Dimensional / Q000295:instrumentation*; D013234:Stem Cells / Q000166:cytology*; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D003094:Collagen