3D-Printed Multi-Channel Scaffolds for Investigating the Foreign Body Response

Abstract

The success of implantable biomaterials is often limited by the foreign body response (FBR), a chronic immune reaction that results in a thick, fibrous capsule that sometimes leads to complete implant failure. Recent research has demonstrated the importance of porosity to mitigate the FBR; however there is much that is still unknown regarding the role that porosity, and the channel regions in between the pores have on the FBR. As such, porous scaffolds with 40 μm rectangular channels of different sizes were designed and fabricated using a stereolithography (SLA) 3D printing approach. By adjusting the printing modulation, velocity and focus values, we demonstrated the capability to produce various porous scaffold designs with high precision in a single print. Furthermore, additional in vivo studies showcased that these porous scaffolds with a 40 μm cubical cross-section, rectangular channels can reduce the fibrotic capsule thickness, albeit at lower levels of cellularization. This research showcased, however, the potential for utilizing 3D printers to create new porous scaffolds, and provided valuable information towards engineering biomaterials to better mitigate the foreign body response.