title: Deterministic encapsulation of single cells in thin tunable microgels for niche modelling and therapeutic delivery.
abstract: Existing techniques to encapsulate cells into microscale hydrogels generally yield high polymer-to-cell ratios and lack control over the hydrogel's mechanical properties. Here, we report a microfluidic-based method for encapsulating single cells in an approximately six-micrometre layer of alginate that increases the proportion of cell-containing microgels by a factor of ten, with encapsulation efficiencies over 90%. We show that in vitro cell viability was maintained over a three-day period, that the microgels are mechanically tractable, and that, for microscale cell assemblages of encapsulated marrow stromal cells cultured in microwells, osteogenic differentiation of encapsulated cells depends on gel stiffness and cell density. We also show that intravenous injection of singly encapsulated marrow stromal cells into mice delays clearance kinetics and sustains donor-derived soluble factors in vivo. The encapsulation of single cells in tunable hydrogels should find use in a variety of tissue engineering and regenerative medicine applications.
authors: Wyss Institute for Biologically Inspired Engineering at Harvard University, Cambridge, Massachusetts 02138, USA.|School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Angelo S
authors: AS
authors: Mao
authors: Wyss Institute for Biologically Inspired Engineering at Harvard University, Cambridge, Massachusetts 02138, USA.|School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.|Department of Pharmacology and Department of Bioengineering, University of Illinois College of Medicine, Chicago, Illinois 60612, USA.
authors: Jae-Won
authors: JW
authors: Shin
authors: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Stefanie
authors: S
authors: Utech
authors: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.|Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.|Biomaterials and Tissue Engineering Laboratory, School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
authors: Huanan
authors: H
authors: Wang
authors: Wyss Institute for Biologically Inspired Engineering at Harvard University, Cambridge, Massachusetts 02138, USA.|School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Oktay
authors: O
authors: Uzun
authors: Wyss Institute for Biologically Inspired Engineering at Harvard University, Cambridge, Massachusetts 02138, USA.|School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Weiwei
authors: W
authors: Li
authors: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Madeline
authors: M
authors: Cooper
authors: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Yuebi
authors: Y
authors: Hu
authors: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.|Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Liyuan
authors: L
authors: Zhang
authors: Wyss Institute for Biologically Inspired Engineering at Harvard University, Cambridge, Massachusetts 02138, USA.|School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.|Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: David A
authors: DA
authors: Weitz
authors: Wyss Institute for Biologically Inspired Engineering at Harvard University, Cambridge, Massachusetts 02138, USA.|School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: David J
authors: DJ
authors: Mooney
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004867:Equipment Design; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D051379:Mice; D055153:Stem Cell Niche; D033581:Stem Cell Transplantation / Q000295:instrumentation* / Q000379:methods; D013234:Stem Cells / Q000166:cytology* / Q000502:physiology; D023822:Tissue Engineering / Q000295:instrumentation* / Q000379:methods; D054457:Tissue Scaffolds
chemical_list: D020100:Hydrogels