title: Dewetting based fabrication of fibrous micro-scaffolds as potential injectable cell carriers.
abstract: Although regenerative medicine utilizing tissue scaffolds has made enormous strides in recent years, many constraints still hamper their effectiveness. A limitation of many scaffolds is that they form surface patches, which are not particularly effective for some types of "wounds" that are deep within tissues, e.g., stroke and myocardial infarction. In this study, we reported the generation of fibrous micro-scaffolds feasible for delivering cells by injection into the tissue parenchyma. The micro-scaffolds (widths<100μm) were made by dewetting of poly(lactic-co-glycolic acid) thin films containing parallel strips, and cells were seeded to form cell/polymer micro-constructs during or post the micro-scaffold fabrication process. Five types of cells including rat induced vascular progenitor cells were assessed for the formation of the micro-constructs. Critical factors in forming fibrous micro-scaffolds via dewetting of polymer thin films were found to be properties of polymers and supporting substrates, temperature, and proteins in the culture medium. Also, the ability of cells to attach to the micro-scaffolds was essential in forming cell/polymer micro-constructs. Both in vitro and in vivo assessments of injecting these micro-scaffolding constructs showed, as compared to free cells, enhanced cell retention at the injected site, which could lead to improved tissue engineering and regeneration.
authors.affiliation: Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, United States.
authors.forename: Hokyung
authors.initials: H
authors.lastname: Song
authors.affiliation: Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 SR44, PO Box 95, Rootstown, OH 44272, United States.
authors.forename: Liya
authors.initials: L
authors.lastname: Yin
authors.affiliation: Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 SR44, PO Box 95, Rootstown, OH 44272, United States.
authors.forename: William M
authors.initials: WM
authors.lastname: Chilian
authors.affiliation: Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, United States. Electronic address: bimin@uakron.edu.
authors.forename: Bi-Min
authors.initials: BM
authors.lastname: Zhang Newby
mesh_terms: D000818:Animals; D018914:Cells, Immobilized / Q000378:metabolism / Q000637:transplantation; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D051381:Rats; D017207:Rats, Sprague-Dawley; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000378:metabolism*; D054457:Tissue Scaffolds / Q000737:chemistry*
keywords: Cell retention; Dewetting; Fibrous micro-constructs; Injectable constructs; Tissue engineering and regeneration