title: Improved cell infiltration of electrospun nanofiber mats for layered tissue constructs.
abstract: While achieving the spatial organization of cells within 3D assembled nanofiber/cell constructs via nanofiber-enabled cell layering, the small sizes of inter-fiber pores of the electrospun nanofiber mats could significantly limit cell penetration across the layers for rapid formation of an integrated tissue construct. To address this challenge, efforts were made to improve cell-infiltration of electrospun nanofiber mats by modulating the density distribution and spatial organization of the fibers during electrospinning. Collection of collagen-containing electrospun nanofibers (300-600 nm in diameter) onto the surface of a stainless steel metal mesh (1 mm × 1 mm in mesh size) led to the periodic alternation of fiber density from densely packed to loosely arranged distribution within the same mat, in which the densely packed fibers maintained the structural integrity while the region of loose fibers allowed for cell penetration. Along with improved cell infiltration, the distinct fiber organization between dense and loose fiber regions also induced different morphology of fibroblasts (stellate vs. elongated spindle-like). Assembly of cell-seeded nanofiber sheets into 3D constructs with such periodically organized nanofiber mats further demonstrated their advantages in improving cell penetration across layers in comparison to either random or aligned nanofiber mats. Taken together, modulation of nanofiber density to enlarge the pore size is effective to improve cell infiltration through electrospun mats for better tissue formation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1479-1488, 2016.
authors: Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, 07030.
authors: Seyed Babak
authors: SB
authors: Mahjour
authors: Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, 07030.
authors: Farshid
authors: F
authors: Sefat
authors: Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, 07030.
authors: Yevgeniy
authors: Y
authors: Polunin
authors: Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, 07030.
authors: Lichen
authors: L
authors: Wang
authors: Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, 07030.
authors: Hongjun
authors: H
authors: Wang
mesh_terms: D000818:Animals; D048430:Cell Shape; D003198:Computer Simulation; D004560:Electricity; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D011091:Polyesters; C016240:polycaprolactone
keywords: cell infiltration; collagen; layered tissue constructs; nanofibers; polycaprolactone (PCL)