Bioprinting of Stem Cells: Interplay of Bioprinting Process, Bioinks, and Stem Cell Properties.

Combining the advantages of 3D bioprinting technology and biological characteristics of stem cells, bioprinting of stem cells is recognized as a novel technology with broad applications in biological study, drug testing, tissue engineering, regenerative medicine, etc. However, the biological performance and functional reconstruction of stem cells are greatly influenced by both the bioprinting process and post-bioprinting culture conditions, which are critical factors to consider for further applications. Here we review the recent development of stem cell bioprinting technology and conclude on the major factors regulating stem cell viability, proliferation, differentiation, and function from the aspects of the choice of bioprinting techniques, the modulation of bioprinting parameters, and the regulation of the stem cell niche in the whole lifespan of bioprinting practices. We aim to provide a comprehensive consideration and guidance regarding the bioprinting of stem cells for optimization of this promising technology in biological and medical applications.

[1]  Tao Xu,et al.  Viability and electrophysiology of neural cell structures generated by the inkjet printing method. , 2006, Biomaterials.

[2]  Roger J. Narayan,et al.  Stereolithography in tissue engineering , 2014, Journal of Materials Science: Materials in Medicine.

[3]  M. Damaser,et al.  Stem cells as drug delivery methods: application of stem cell secretome for regeneration. , 2015, Advanced drug delivery reviews.

[4]  Anthony Atala,et al.  3D bioprinting of tissues and organs , 2014, Nature Biotechnology.

[5]  M. Beal,et al.  Functional engraftment of human ES cell–derived dopaminergic neurons enriched by coculture with telomerase-immortalized midbrain astrocytes , 2006, Nature Medicine.

[6]  Bradley R Ringeisen,et al.  Laser printing of pluripotent embryonal carcinoma cells. , 2004, Tissue engineering.

[7]  A. Ueno,et al.  Cell patterning through inkjet printing of one cell per droplet. , 2012, Biofabrication.

[8]  Guifang Gao,et al.  Human cartilage tissue fabrication using three-dimensional inkjet printing technology. , 2014, Journal of visualized experiments : JoVE.

[9]  C. Highley,et al.  Direct 3D Printing of Shear‐Thinning Hydrogels into Self‐Healing Hydrogels , 2015, Advanced materials.

[10]  Vladimir Mironov,et al.  Organ printing: tissue spheroids as building blocks. , 2009, Biomaterials.

[11]  Marcy Zenobi-Wong,et al.  Nanostructured Pluronic hydrogels as bioinks for 3D bioprinting , 2015, Biofabrication.

[12]  Tao Xu,et al.  Inkjet-mediated gene transfection into living cells combined with targeted delivery. , 2009, Tissue engineering. Part A.

[13]  Guifang Gao,et al.  Bioactive nanoparticles stimulate bone tissue formation in bioprinted three-dimensional scaffold and human mesenchymal stem cells. , 2014, Biotechnology journal.

[14]  Yang Song,et al.  Osteogenic Differentiation of Three-Dimensional Bioprinted Constructs Consisting of Human Adipose-Derived Stem Cells In Vitro and In Vivo , 2016, PloS one.

[15]  Peter Pivonka,et al.  Handheld Co-Axial Bioprinting: Application to in situ surgical cartilage repair , 2017, Scientific Reports.

[16]  Deok‐Ho Kim,et al.  Printing three-dimensional tissue analogues with decellularized extracellular matrix bioink , 2014, Nature Communications.

[17]  Ken Doyle,et al.  Bioprinting: From Patches to Parts , 2014 .

[18]  Alexandra L. Rutz,et al.  A Multimaterial Bioink Method for 3D Printing Tunable, Cell‐Compatible Hydrogels , 2015, Advanced materials.

[19]  Xiaofeng Cui,et al.  Application of inkjet printing to tissue engineering , 2006, Biotechnology journal.

[20]  J. Hubbell,et al.  Synthetic biomaterials as instructive extracellular microenvironments for morphogenesis in tissue engineering , 2005, Nature Biotechnology.

[21]  A. Khademhosseini,et al.  Microfluidic Bioprinting of Heterogeneous 3D Tissue Constructs Using Low‐Viscosity Bioink , 2016, Advanced materials.

[22]  James J. Yoo,et al.  Bioprinted Amniotic Fluid‐Derived Stem Cells Accelerate Healing of Large Skin Wounds , 2012, Stem cells translational medicine.

[23]  S. Yamanaka,et al.  Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors , 2006, Cell.

[24]  B. Holmes,et al.  3D printed nanocomposite matrix for the study of breast cancer bone metastasis. , 2016, Nanomedicine : nanotechnology, biology, and medicine.

[25]  S. Levenberg,et al.  Vascularization : The Conduit to Viable Engineered Tissues , 2010 .

[26]  A. Johnson,et al.  Multimaterial polyacrylamide: fabrication with electrohydrodynamic jet printing, applications, and modeling , 2014, Biofabrication.

[27]  D. Cho,et al.  Biomimetic 3D tissue printing for soft tissue regeneration. , 2015, Biomaterials.

[28]  Todd C McDevitt,et al.  Pre-conditioning mesenchymal stromal cell spheroids for immunomodulatory paracrine factor secretion. , 2014, Cytotherapy.

[29]  Wei Zhu,et al.  Improved Human Bone Marrow Mesenchymal Stem Cell Osteogenesis in 3D Bioprinted Tissue Scaffolds with Low Intensity Pulsed Ultrasound Stimulation , 2016, Scientific Reports.

[30]  V. Mironov,et al.  Modeling fusion of cellular aggregates in biofabrication using phase field theories. , 2012, Journal of theoretical biology.

[31]  Ying Mei,et al.  3D printing facilitated scaffold-free tissue unit fabrication , 2014, Biofabrication.

[32]  J. Temenoff,et al.  Cell number and chondrogenesis in human mesenchymal stem cell aggregates is affected by the sulfation level of heparin used as a cell coating. , 2016, Journal of biomedical materials research. Part A.

[33]  Ying Mei,et al.  3D Bioprinting for Vascularized Tissue Fabrication , 2016, Annals of Biomedical Engineering.

[34]  D W Hutmacher,et al.  Three-Dimensional Bioprinting for Regenerative Dentistry and Craniofacial Tissue Engineering , 2015, Journal of dental research.

[35]  Liliang Ouyang,et al.  A Generalizable Strategy for the 3D Bioprinting of Hydrogels from Nonviscous Photo‐crosslinkable Inks , 2017, Advanced materials.

[36]  James J. Yoo,et al.  Complex heterogeneous tissue constructs containing multiple cell types prepared by inkjet printing technology. , 2013, Biomaterials.

[37]  Seung-Joon Song,et al.  Sodium alginate hydrogel-based bioprinting using a novel multinozzle bioprinting system. , 2011, Artificial organs.

[38]  Matthew J. Dalby,et al.  Nanotopographical Control of Stem Cell Differentiation , 2010, Journal of tissue engineering.

[39]  M. Foss,et al.  The influence of glancing angle deposited nano-rough platinum surfaces on the adsorption of fibrinogen and the proliferation of primary human fibroblasts , 2009, Nanotechnology.

[40]  F. Marga,et al.  Toward engineering functional organ modules by additive manufacturing , 2012, Biofabrication.

[41]  Jian Tang,et al.  The regulation of stem cell differentiation by cell-cell contact on micropatterned material surfaces. , 2010, Biomaterials.

[42]  F. Lin,et al.  Biomimetic injectable HUVEC‐adipocytes/collagen/alginate microsphere co‐cultures for adipose tissue engineering , 2013, Biotechnology and bioengineering.

[43]  Scott A. Wilson,et al.  Shear-Thinning and Thermo-Reversible Nanoengineered Inks for 3D Bioprinting. , 2017, ACS applied materials & interfaces.

[44]  Rashid Bashir,et al.  Three-dimensional photopatterning of hydrogels using stereolithography for long-term cell encapsulation. , 2010, Lab on a chip.

[45]  Feng Xu,et al.  Embryonic stem cell bioprinting for uniform and controlled size embryoid body formation. , 2011, Biomicrofluidics.

[46]  P. Calvert Printing Cells , 2007, Science.

[47]  Ying Tang,et al.  Projection Stereolithographic Fabrication of BMP-2 Gene-activated Matrix for Bone Tissue Engineering , 2017, Scientific Reports.

[48]  Debby Gawlitta,et al.  Scaffold porosity and oxygenation of printed hydrogel constructs affect functionality of embedded osteogenic progenitors. , 2011, Tissue engineering. Part A.

[49]  Alan Faulkner-Jones,et al.  Development of a valve-based cell printer for the formation of human embryonic stem cell spheroid aggregates , 2013, Biofabrication.

[50]  Umut A. Gurkan,et al.  Engineering Anisotropic Biomimetic Fibrocartilage Microenvironment by Bioprinting Mesenchymal Stem Cells in Nanoliter Gel Droplets , 2014, Molecular pharmaceutics.

[51]  W. Świȩszkowski,et al.  Microfluidic-enhanced 3D bioprinting of aligned myoblast-laden hydrogels leads to functionally organized myofibers in vitro and in vivo. , 2017, Biomaterials.

[52]  Wim E Hennink,et al.  25th Anniversary Article: Engineering Hydrogels for Biofabrication , 2013, Advanced materials.

[53]  Ryan S. Udan,et al.  Understanding vascular development , 2013, Wiley interdisciplinary reviews. Developmental biology.

[54]  I. Noh,et al.  Recent trends in bioinks for 3D printing , 2018, Biomaterials Research.

[55]  Anthony Atala,et al.  Tissue-specific extracellular matrix coatings for the promotion of cell proliferation and maintenance of cell phenotype. , 2009, Biomaterials.

[56]  Tao Xu,et al.  3D bioprinted glioma stem cells for brain tumor model and applications of drug susceptibility , 2016, Biofabrication.

[57]  David T Corr,et al.  The maintenance of pluripotency following laser direct-write of mouse embryonic stem cells. , 2011, Biomaterials.

[58]  K. Metzeler,et al.  Molecular Genetic Characterization of Individual Cancer Cells Isolated via Single-Cell Printing , 2016, PloS one.

[59]  S. Hsu,et al.  3D bioprinting of neural stem cell-laden thermoresponsive biodegradable polyurethane hydrogel and potential in central nervous system repair. , 2015, Biomaterials.

[60]  Harrie Weinans,et al.  Sustained Release of BMP-2 in Bioprinted Alginate for Osteogenicity in Mice and Rats , 2013, PloS one.

[61]  F. Lin,et al.  Injectable cell/hydrogel microspheres induce the formation of fat lobule-like microtissues and vascularized adipose tissue regeneration , 2012, Biofabrication.

[62]  Anthony Atala,et al.  A 3D bioprinted complex structure for engineering the muscle–tendon unit , 2015, Biofabrication.

[63]  Ryan B. Wicker,et al.  Stereolithography of Three-Dimensional Bioactive Poly(Ethylene Glycol) Constructs with Encapsulated Cells , 2006, Annals of Biomedical Engineering.

[64]  X. Ren,et al.  On the road to bioartificial organs , 2014, Pflügers Archiv - European Journal of Physiology.

[65]  Ursula Graf-Hausner,et al.  Standardized 3D Bioprinting of Soft Tissue Models with Human Primary Cells , 2016, Journal of laboratory automation.

[66]  W. Hennink,et al.  Hydrogels as extracellular matrices for skeletal tissue engineering: state-of-the-art and novel application in organ printing. , 2007, Tissue engineering.

[67]  Xiaofeng Cui,et al.  Bioprinting Cartilage Tissue from Mesenchymal Stem Cells and PEG Hydrogel. , 2017, Methods in molecular biology.

[68]  R. Wells The role of matrix stiffness in regulating cell behavior , 2008, Hepatology.

[69]  J. Lewis,et al.  3D Bioprinting of Vascularized, Heterogeneous Cell‐Laden Tissue Constructs , 2014, Advanced materials.

[70]  Chwee Teck Lim,et al.  Microfluidic cell trap array for controlled positioning of single cells on adhesive micropatterns. , 2013, Lab on a chip.

[71]  N. Leipzig,et al.  Short Duration Electrical Stimulation to Enhance Neurite Outgrowth and Maturation of Adult Neural Stem Progenitor Cells , 2014, Annals of Biomedical Engineering.

[72]  Wei Sun,et al.  Effect of bioink properties on printability and cell viability for 3D bioplotting of embryonic stem cells , 2016, Biofabrication.

[73]  O. Stojadinović,et al.  Stem Cells in Skin Regeneration, Wound Healing, and Their Clinical Applications , 2015, International journal of molecular sciences.

[74]  Horst Fischer,et al.  Controlling Shear Stress in 3D Bioprinting is a Key Factor to Balance Printing Resolution and Stem Cell Integrity , 2016, Advanced healthcare materials.

[75]  Ibrahim T. Ozbolat,et al.  The bioink: A comprehensive review on bioprintable materials. , 2017, Biotechnology advances.

[76]  Jackie Y Ying,et al.  The effect of matrix stiffness on mesenchymal stem cell differentiation in a 3D thixotropic gel. , 2010, Biomaterials.

[77]  O. Hermanson,et al.  Inkjet printing of macromolecules on hydrogels to steer neural stem cell differentiation. , 2007, Biomaterials.

[78]  D Stamatialis,et al.  Fabrication of three-dimensional bioplotted hydrogel scaffolds for islets of Langerhans transplantation , 2015, Biofabrication.

[79]  Xi Chen,et al.  Three-dimensional bioprinting of embryonic stem cells directs highly uniform embryoid body formation , 2015, Biofabrication.

[80]  K. Burridge,et al.  From mechanical force to RhoA activation. , 2012, Biochemistry.

[81]  Hyeongjin Lee,et al.  Fabrication of hASCs-laden structures using extrusion-based cell printing supplemented with an electric field. , 2016, Acta biomaterialia.

[82]  T. Boland,et al.  Cell damage evaluation of thermal inkjet printed Chinese hamster ovary cells , 2010, Biotechnology and bioengineering.

[83]  Rashid Bashir,et al.  Patterned Three‐Dimensional Encapsulation of Embryonic Stem Cells using Dielectrophoresis and Stereolithography , 2013, Advanced healthcare materials.

[84]  Yilin Cao,et al.  Recent progress in stem cell differentiation directed by material and mechanical cues , 2016, Biomedical materials.

[85]  P. Ajayan,et al.  An open-pored gelatin/hydroxyapatite composite as a potential bone substitute , 2008, Journal of materials science. Materials in medicine.

[86]  P Koltay,et al.  Single-cell PCR of genomic DNA enabled by automated single-cell printing for cell isolation. , 2015, Biosensors & bioelectronics.

[87]  Mark A. Skylar-Scott,et al.  Three-dimensional bioprinting of thick vascularized tissues , 2016, Proceedings of the National Academy of Sciences.

[88]  Zhijian Shen,et al.  Effects of hierarchical micro/nano-topographies on the morphology, proliferation and differentiation of osteoblast-like cells. , 2016, Colloids and surfaces. B, Biointerfaces.

[89]  P. Yuen,et al.  Microstructured multi-well plate for three-dimensional packed cell seeding and hepatocyte cell culture. , 2014, Biomicrofluidics.

[90]  FischerHorst,et al.  The stiffness and structure of three-dimensional printed hydrogels direct the differentiation of mesenchymal stromal cells toward adipogenic and osteogenic lineages. , 2015 .

[91]  MyungGu Yeo,et al.  An Innovative Collagen-Based Cell-Printing Method for Obtaining Human Adipose Stem Cell-Laden Structures Consisting of Core-Sheath Structures for Tissue Engineering. , 2016, Biomacromolecules.

[92]  Jeroen Rouwkema,et al.  Vascularization in tissue engineering. , 2008, Trends in biotechnology.

[93]  R. Samanipour,et al.  A simple and high-resolution stereolithography-based 3D bioprinting system using visible light crosslinkable bioinks , 2015, Biofabrication.

[94]  Fan Yang,et al.  Sliding Hydrogels with Mobile Molecular Ligands and Crosslinks as 3D Stem Cell Niche , 2016, Advanced materials.

[95]  Johnny Huard,et al.  Engineering spatial control of multiple differentiation fates within a stem cell population. , 2011, Biomaterials.

[96]  H. Iwata,et al.  Maturation of human iPS cell-derived dopamine neuron precursors in alginate-Ca(2+) hydrogel. , 2015, Biochimica et biophysica acta.

[97]  Xiaofeng Yang,et al.  In-silico analysis on biofabricating vascular networks using kinetic Monte Carlo simulations , 2014, Biofabrication.

[98]  Guifang Gao,et al.  Three-dimensional bioprinting in tissue engineering and regenerative medicine , 2015, Biotechnology Letters.

[99]  Wonhye Lee,et al.  Bio-printing of collagen and VEGF-releasing fibrin gel scaffolds for neural stem cell culture , 2010, Experimental Neurology.

[100]  Teng Ma,et al.  Facile functionalization and assembly of live cells with microcontact-printed polymeric biomaterials. , 2015, Acta biomaterialia.

[101]  Xiaofeng Cui,et al.  Improved properties of bone and cartilage tissue from 3D inkjet-bioprinted human mesenchymal stem cells by simultaneous deposition and photocrosslinking in PEG-GelMA , 2015, Biotechnology Letters.

[102]  Jeffrey A. Hubbell,et al.  Polymeric biomaterials with degradation sites for proteases involved in cell migration , 1999 .

[103]  Dominique Shum-Tim,et al.  Neovascularization in Tissue Engineering , 2012, Cells.

[104]  J Ciurana,et al.  The first systematic analysis of 3D rapid prototyped poly(ε-caprolactone) scaffolds manufactured through BioCell printing: the effect of pore size and geometry on compressive mechanical behaviour and in vitro hMSC viability , 2013, Biofabrication.

[105]  F. Guillemot,et al.  Laser assisted bioprinting of engineered tissue with high cell density and microscale organization. , 2010, Biomaterials.

[106]  Hyeongjin Lee,et al.  A New Approach for Fabricating Collagen/ECM‐Based Bioinks Using Preosteoblasts and Human Adipose Stem Cells , 2015, Advanced healthcare materials.

[107]  S. Sen,et al.  Matrix Elasticity Directs Stem Cell Lineage Specification , 2006, Cell.

[108]  T. Boland,et al.  Inkjet printing for high-throughput cell patterning. , 2004, Biomaterials.

[109]  Dongsheng Liu,et al.  Rapid formation of a supramolecular polypeptide-DNA hydrogel for in situ three-dimensional multilayer bioprinting. , 2015, Angewandte Chemie.

[110]  F. Guillemot,et al.  Controlling laser-induced jet formation for bioprinting mesenchymal stem cells with high viability and high resolution , 2014, Biofabrication.

[111]  Ji-Seon Lee,et al.  A novel cell-printing method and its application to hepatogenic differentiation of human adipose stem cell-embedded mesh structures , 2015, Scientific Reports.

[112]  Boris N. Chichkov,et al.  Laser assisted cell printing. , 2013 .

[113]  Bradley R. Ringeisen,et al.  Laser Printing of Single Cells: Statistical Analysis, Cell Viability, and Stress , 2005, Annals of Biomedical Engineering.

[114]  Yong Huang,et al.  Laser-based direct-write techniques for cell printing , 2010, Biofabrication.

[115]  F. Gage,et al.  Mammalian neural stem cells. , 2000, Science.

[116]  L. Koch,et al.  Human stem cell based corneal tissue mimicking structures using laser-assisted 3D bioprinting and functional bioinks. , 2018, Biomaterials.

[117]  Ibrahim T. Ozbolat,et al.  Bioprinting for vascular and vascularized tissue biofabrication. , 2017, Acta biomaterialia.

[118]  Jun-Ha Hwang,et al.  Extracellular Matrix Stiffness Regulates Osteogenic Differentiation through MAPK Activation , 2015, PloS one.

[119]  Eric D. Miller,et al.  Microenvironments Engineered by Inkjet Bioprinting Spatially Direct Adult Stem Cells Toward Muscle‐ and Bone‐Like Subpopulations , 2008, Stem cells.

[120]  Michele Marcolongo,et al.  Characterization of cell viability during bioprinting processes. , 2009, Biotechnology journal.

[121]  Bin Duan,et al.  Optimizing Photo-Encapsulation Viability of Heart Valve Cell Types in 3D Printable Composite Hydrogels , 2016, Annals of Biomedical Engineering.

[122]  Buddy D Ratner,et al.  The surface molecular functionality of decellularized extracellular matrices. , 2011, Biomaterials.

[123]  Brian Derby,et al.  Printing and Prototyping of Tissues and Scaffolds , 2012, Science.

[124]  M. Pittenger,et al.  Multilineage potential of adult human mesenchymal stem cells. , 1999, Science.

[125]  Qi Wang,et al.  A phase field approach for multicellular aggregate fusion in biofabrication. , 2013, Journal of biomechanical engineering.

[126]  Kai Zhang,et al.  Block-Cell-Printing for live single-cell printing , 2014, Proceedings of the National Academy of Sciences.

[127]  Peter F. M. Choong,et al.  Chondrogenesis of Infrapatellar Fat Pad Derived Adipose Stem Cells in 3D Printed Chitosan Scaffold , 2014, PloS one.

[128]  Alan Faulkner-Jones,et al.  Bioprinting of human pluripotent stem cells and their directed differentiation into hepatocyte-like cells for the generation of mini-livers in 3D , 2015, Biofabrication.

[129]  Ryan Wicker,et al.  Stereolithography of spatially controlled multi-material bioactive poly(ethylene glycol) scaffolds. , 2010, Acta biomaterialia.

[130]  Stuart K Williams,et al.  Three-dimensional bioassembly tool for generating viable tissue-engineered constructs. , 2004, Tissue engineering.

[131]  U. Demirci,et al.  Bioprinting for stem cell research. , 2013, Trends in biotechnology.

[132]  Vladimir Mironov,et al.  Organ printing: from bioprinter to organ biofabrication line. , 2011, Current opinion in biotechnology.

[133]  Anthony Atala,et al.  Biomaterials for Integration with 3-D Bioprinting , 2014, Annals of Biomedical Engineering.

[134]  Seyed Jamaleddin Mousavi,et al.  Role of Mechanical Cues in Cell Differentiation and Proliferation: A 3D Numerical Model , 2015, PloS one.

[135]  John A Reid,et al.  Accessible bioprinting: adaptation of a low-cost 3D-printer for precise cell placement and stem cell differentiation , 2016, Biofabrication.

[136]  Xiaofeng Cui,et al.  Inkjet-bioprinted acrylated peptides and PEG hydrogel with human mesenchymal stem cells promote robust bone and cartilage formation with minimal printhead clogging. , 2015, Biotechnology journal.

[137]  Wei Sun,et al.  Mesenchymal stem cell printing and process regulated cell properties , 2015, Biofabrication.

[138]  L. Niklason,et al.  Scaffold-free vascular tissue engineering using bioprinting. , 2009, Biomaterials.

[139]  Jaesoon Choi,et al.  Cellular behavior in micropatterned hydrogels by bioprinting system depended on the cell types and cellular interaction. , 2013, Journal of bioscience and bioengineering.

[140]  Min Zhu,et al.  Human adipose tissue is a source of multipotent stem cells. , 2002, Molecular biology of the cell.

[141]  Wei Sun,et al.  Effects of dispensing pressure and nozzle diameter on cell survival from solid freeform fabrication-based direct cell writing. , 2008, Tissue engineering. Part A.

[142]  Ralph Müller,et al.  Tunable hydrogel composite with two-step processing in combination with innovative hardware upgrade for cell-based three-dimensional bioprinting. , 2014, Acta biomaterialia.

[143]  Ardo Illaste,et al.  Functional Characterization and Comparison of Intercellular Communication in Stem Cell‐Derived Cardiomyocytes , 2015, Stem cells.

[144]  P. Gatenholm,et al.  3D Bioprinting Human Chondrocytes with Nanocellulose-Alginate Bioink for Cartilage Tissue Engineering Applications. , 2015, Biomacromolecules.

[145]  Soyoung Hong,et al.  Inhibition of Rho-Associated Protein Kinase Increases the Angiogenic Potential of Mesenchymal Stem Cell Aggregates via Paracrine Effects. , 2016, Tissue engineering. Part A.

[146]  Wesley R. Legant,et al.  Degradation-mediated cellular traction directs stem cell fate in covalently crosslinked three-dimensional hydrogels , 2013, Nature materials.

[147]  H. Imaishi,et al.  Microarrays of phospholipid bilayers generated by inkjet printing. , 2013, Langmuir : the ACS journal of surfaces and colloids.

[148]  Brian A. Aguado,et al.  Improving viability of stem cells during syringe needle flow through the design of hydrogel cell carriers. , 2012, Tissue engineering. Part A.

[149]  N. Jones Science in three dimensions: The print revolution , 2012, Nature.

[150]  I. Weissman,et al.  Stem cells, cancer, and cancer stem cells , 2001, Nature.

[151]  M Nakamura,et al.  Biomatrices and biomaterials for future developments of bioprinting and biofabrication , 2010, Biofabrication.

[152]  J. Thomson,et al.  Embryonic stem cell lines derived from human blastocysts. , 1998, Science.

[153]  Gordon G Wallace,et al.  Functional 3D Neural Mini‐Tissues from Printed Gel‐Based Bioink and Human Neural Stem Cells , 2016, Advanced healthcare materials.

[154]  Thomas Boland,et al.  Synthesis and characterization of biodegradable elastomeric polyurethane scaffolds fabricated by the inkjet technique. , 2008, Biomaterials.

[155]  R. Zengerle,et al.  Cytocompatibility testing of hydrogels toward bioprinting of mesenchymal stem cells. , 2017, Journal of biomedical materials research. Part A.

[156]  Guillermo A. Gomez,et al.  Biomechanics of epithelial cell islands analyzed by modeling and experimentation , 2016 .

[157]  Pu Chen,et al.  Towards artificial tissue models: past, present, and future of 3D bioprinting , 2016, Biofabrication.

[158]  D T Corr,et al.  Generating size-controlled embryoid bodies using laser direct-write , 2014, Biofabrication.

[159]  Hwan-You Chang,et al.  Recent advances in three‐dimensional multicellular spheroid culture for biomedical research , 2008, Biotechnology journal.

[160]  D. Grijpma,et al.  Differentiation of adipose stem cells seeded towards annulus fibrosus cells on a designed poly(trimethylene carbonate) scaffold prepared by stereolithography , 2017, Journal of tissue engineering and regenerative medicine.

[161]  Sylvain Catros,et al.  Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration , 2016, BioMed research international.

[162]  I. Hutchings,et al.  Adult rat retinal ganglion cells and glia can be printed by piezoelectric inkjet printing , 2013, Biofabrication.

[163]  Dong-Woo Cho,et al.  Biomaterials-based 3D cell printing for next-generation therapeutics and diagnostics. , 2018, Biomaterials.

[164]  J.V.L. da Silva,et al.  Scalable robotic biofabrication of tissue spheroids , 2011, Biofabrication.

[165]  W. Dhert,et al.  Three-dimensional fiber deposition of cell-laden, viable, patterned constructs for bone tissue printing. , 2008, Tissue engineering. Part A.

[166]  Gordon G. Wallace,et al.  Biofabrication: an overview of the approaches used for printing of living cells , 2013, Applied Microbiology and Biotechnology.

[167]  David J Odde,et al.  Micropatterning of living cells by laser-guided direct writing: application to fabrication of hepatic–endothelial sinusoid-like structures , 2006, Nature Protocols.

[168]  Fabien Guillemot,et al.  Cell patterning technologies for organotypic tissue fabrication. , 2011, Trends in biotechnology.

[169]  Wei Sun,et al.  The influence of printing parameters on cell survival rate and printability in microextrusion-based 3D cell printing technology , 2015, Biofabrication.

[170]  K H Kang,et al.  Quantitative optimization of solid freeform deposition of aqueous hydrogels , 2013, Biofabrication.