Three-Dimensional Melt-Electrowritten Polycaprolactone/Chitosan\nScaffolds Enhance Mesenchymal Stem Cell Behavior

Abstract

Melt\nelectrowriting (MEW) is an emerging technique that precisely\nfabricates microfibrous scaffolds, ideal for tissue engineering, where\nbiomimetic microarchitectural detail is required. Polycaprolactone\n(PCL), a synthetic polymer, was selected as the scaffold material\ndue to its biocompatibility, biodegradability, mechanical strength,\nand melt processability. To increase PCL bioactivity, a natural polymer,\nchitosan, was added to construct MEW fibrous composite scaffolds.\nTo date, this is the first study of its kind detailing the effects\nof stem cell behavior on PCL containing chitosan MEW scaffolds. The\naim of this study was to melt electrowrite a range of PCL/chitosan\ntissue-engineered constructs (TECs) and assess their suitability to\npromote the growth of human bone-marrow-derived mesenchymal stem cells\n(hBMSCs). <i>In vitro</i> physical and biological characterizations\nof melt-electrowritten TECs were performed. Physical characterization\nshowed that reproducible, layered micron-range scaffolds could be\nsuccessfully fabricated. As well, cell migration and proliferation\nwere assessed via an assay to monitor cell infiltration throughout\nthe three-dimensional (3D) melt-electrowritten scaffold structure.\nA statistically significant increase (∼140%) in hBMSC proliferation\nin 1 wt % chitosan PCL blends in comparison to PCL-only scaffolds\nwas found when monitored over two weeks. Overall, our study demonstrates\nthe fabrication of melt-electrowritten PCL/chitosan composite scaffolds\nwith controlled microarchitecture and their potential use for regenerative,\ntissue engineering applications.