Technique for internal channelling of hydroentangled nonwoven scaffolds to enhance cell penetration

Abstract

An important requirement in thick, high-porosity scaffolds is to maximise cellular penetration into the interior and avoid necrosis during culture in vitro. Hitherto, reproducible control of the pore structure in nonwoven scaffolds has proved challenging. A new, channelled scaffold manufacturing process is reported based on water jet entanglement of fibres (hydroentangling) around filamentous template to form a coherent scaffold that is subsequently removed. Longitudinally-oriented channels were introduced within the scaffold in controlled proximity using 220 µm diameter cylindrical templates. In this case study, channelled scaffolds composed of poly(l-lactic acid) were manufactured and evaluated in vitro. Environmental scanning electron microscope and µCT (X-ray microtomography) confirmed channel openings in the scaffold cross-section before and after cell culture with human dermal fibroblasts up to 14 weeks. Histology at week 11 indicated that the channels promoted cell penetration and distribution within the scaffold interior. At week 14, cellular matrix deposition was evident in the internal channel walls and the entrances remained unoccluded by cellular matrix suggesting that diffusion conduits for mass transfer of nutrient to the scaffold interior could be maintained.

Novel In Situ-Cross-Linked Electrospun Gelatin/Hydroxyapatite Nonwoven Scaffolds Prove Suitable for Periodontal Tissue Engineering

“…Cellular properties, including deformability and the secretion of proteolytic enzymes, also play a role in this process [131]. Although some studies have addressed the question of how to enhance cellular penetration into nonwoven scaffolds, it is still unclear what therapeutic effect results from these efforts [132][133][134]. Thus, detailed, comparative in vivo studies on these issues are needed in the periodontal context.…”

The Regeneration of Large-Sized and Vascularized Adipose Tissue Using a Tailored Elastic Scaffold and dECM Hydrogels

“…Durham et al manufactured and evaluated channeled scaffolds composed of poly(Ï-lactic acid) in vitro. They reported that channels in thick scaffolds promoted cell penetration and tissue formation by the mass transfer of nutrients to the scaffold interior [28].…”

Microporous cellulosic scaffold as a spheroid culture system modulates chemotherapeutic responses and stemness in hepatocellular carcinoma

“…16 The cell-seeded and unseeded scaffolds were harvested after different days of culture and fixed in 10% (vol/vol) neutral-buffered formalin (NBF) from Sigma-Aldrich. 16 The cell-seeded and unseeded scaffolds were harvested after different days of culture and fixed in 10% (vol/vol) neutral-buffered formalin (NBF) from Sigma-Aldrich.…”

“…2.6 | Histological analysis and immunohistochemistry Histological examination was performed on each scaffold with or without cells, to analyze the general histoarchitecture, the cell density, and spheroids retained in the pores. 16 The cell-seeded and unseeded scaffolds were harvested after different days of culture and fixed in 10% (vol/vol) neutral-buffered formalin (NBF) from Sigma-Aldrich. Postfixation, samples were dehydrated and embedded in paraffin wax.…”