Electrospun Fibrous Mats with High Porosity as Potential Scaffolds for Skin Tissue Engineering

TLDR

Diffusional limitations of mass transport hinder the engineering of highly vascularized tissues, and conventional electrospinning often fails to produce large pores needed for cell infiltration. The study aims to develop a slow rotating frame cylinder collector to extend pore size and increase porosity of electrospun fibrous scaffolds. The slow rotating frame cylinder was employed to fabricate mats with 92.4 % porosity and 132.7 μm pores, onto which human dermal fibroblasts were seeded using a cell‑culture ring to prevent shrinkage. Highly porous mats supported greater HDF viability, uniform distribution, infiltration beyond 100 μm, and collagen secretion, indicating their potential as skin tissue engineering scaffolds.

Abstract

Diffusional limitations of mass transport have adverse effects on engineering tissues that normally have high vascularity and cellularity. The current electrospinning method is not always successful to create micropores to encourage cell infiltration within the scaffold, especially when relatively large-sized pores are required. In this study, a slow rotating frame cylinder was developed as the collector to extend the pore size and increase the porosity of electrospun fibrous scaffolds. Fibrous mats with porosity as high as 92.4% and average pore size of 132.7 μm were obtained. Human dermal fibroblasts (HDFs) were seeded onto these mats, which were fixed on a cell-culture ring to prevent the shrinkage and contraction during the incubation. The viability test indicated that significantly more HDFs were generated on highly porous fibrous mats. Toluidine blue staining showed that the highly porous scaffold provided mechanical support for cells to maintain uniform distribution. The cross-section observations indicated that cells migrated and infiltrated more than 100 μm inside highly porous fibrous mats after 5 d incubation. The immunohistochemistry analysis demonstrated that cells began secreting collagen, which is the main constituent of extracellular matrix. It is supposed that highly porous electrospun fibrous scaffolds could be constructed by this elaboration and may be used for skin tissue engineering.