Novel nanofibrous bilayer scaffolds incorporated with different cells for regenerating complex body tissues

Abstract

Tissue engineering has advanced significantly but regenerating complex body tissues is still a formidable task. Complex tissues generally display multilayer structures involving different cells. It is therefore important to develop multilayered scaffolds incorporated with different cells. In this study, a continuous process of concurrent electrospinning and electrospray was investigated to produce nanofibrous scaffolds with a bilayer structure incorporated with different cells. PLGA (LA:GA at 50:50 and 75:25) was electrospun into bilayer scaffolds: one layer of PLGA(50/50) fibers and another layer of PLGA(75/25) fibers. Coaxial electrospray was used to fabricate cell-encapsulated sodium alginate (SA) microspheres. SA microspheres containing human umbilical vein endothelial cell (HUVEC) or human aortic smooth muscle cell (HASMC) were respectively incorporated in the PLGA(50/50) layer and PLGA(75/25) layer. After dissolving SA shell, cells were released in scaffolds. The structure of cell-laden scaffolds was studied. The viability, distribution and proliferation of HUVECs and HASMCs in scaffolds were investigated. Results showed cell viability was well maintained in the scaffold fabrication process and cells were distributed in respective layers of the scaffolds. This study demonstrates the potential of the new technology for making novel cell-laden scaffolds.