title: Efficient One-Step Production of Microencapsulated Hepatocyte Spheroids with Enhanced Functions.
abstract: Hepatocyte spheroids microencapsulated in hydrogels can contribute to liver research in various capacities. The conventional approach of microencapsulating spheroids produces a variable number of spheroids per microgel and requires an extra step of spheroid loading into the gel. Here, a microfluidics technology bypassing the step of spheroid loading and controlling the spheroid characteristics is reported. Double-emulsion droplets are used to generate microencapsulated homotypic or heterotypic hepatocyte spheroids (all as single spheroids <200 μm in diameter) with enhanced functions in 4 h. The composition of the microgel is tunable as demonstrated by improved hepatocyte functions during 24 d culture (albumin secretion, urea secretion, and cytochrome P450 activity) when alginate-collagen composite hydrogel is used instead of alginate. Hepatocyte spheroids in alginate-collagen also perform better than hepatocytes cultured in collagen-sandwich configuration. Moreover, hepatocyte functions are significantly enhanced when hepatocytes and endothelial progenitor cells (used as a novel supporting cell source) are co-cultured to form composite spheroids at an optimal ratio of 5:1, which could be further boosted when encapsulated in alginate-collagen. This microencapsulated-spheroid formation technology with high yield, versatility, and uniformity is envisioned to be an enabling technology for liver tissue engineering as well as biomanufacturing.
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.|Department of Biomedical Engineering, Columbia University, New York, NY, 10032, USA.
authors.forename: Hon Fai
authors.initials: HF
authors.lastname: Chan
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.|Department of Biomedical Engineering, Columbia University, New York, NY, 10032, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.|Department of Biomedical Engineering, Columbia University, New York, NY, 10032, USA.
authors.forename: Kam W
authors.initials: KW
authors.lastname: Leong
mesh_terms: D000464:Alginates / Q000737:chemistry; D000818:Animals; D003094:Collagen / Q000378:metabolism; D020723:Glucuronic Acid / Q000737:chemistry; D022781:Hepatocytes / Q000166:cytology* / Q000378:metabolism; D006603:Hexuronic Acids / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry; D044085:Microfluidics / Q000379:methods; D051381:Rats; D018874:Spheroids, Cellular / Q000166:cytology / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D023822:Tissue Engineering / Q000379:methods
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020100:Hydrogels; D020723:Glucuronic Acid; D003094:Collagen
keywords: encapsulation; hepatocyte spheroids; microdroplets; microfluidics; tissue engineering