Three-dimensional meltblowing as a high-speed fabrication process for tendon tissue engineered scaffolds

Rotator cuff tears continue to be a critical challenge for successful repair due to the formation of fibrotic scar tissue during healing. Tendon tissue engineering seeks to improve these outcomes using nonwoven fabrication methods to produce biomimetic scaffolds. Meltblowing has several advantages over other nonwoven approaches including non-toxic fabrication processes and being high-throughput and economical, while accurately producing fiber diameters comparable to native tendon microstructure. Recently 3D meltblowing (3DMB) introduced high degrees of tunability to the core process, allowing for production of highly aligned fiber mats at anatomically relevant dimensions. Here, we evaluated 3DMB scaffolds fabricated using poly-L-lactic acid (PLA) and poly-ε-caprolactone (PCL) by characterizing scaffold properties before and after culture with human adipose stem cells (hASCs). Mechanical and fiber characterization of 3DMB scaffolds closely resembled tendon microarchitecture by exhibiting high fiber alignment and mechanical anisotropy. hASC-seeded 3DMB scaffolds after 28 days of culture proliferated and deposited aligned tendon-like extracellular matrix. Furthermore, cell culture enhanced the Young's modulus of PLA 3DMB scaffolds and improved yield stress, yield stretch, and stiffness of both 3DMB scaffolds. The proteome of cultured 3DMB scaffolds increased expression of tendon-related proteins after 28 days of culture, but polymer-dependent differences in glycoprotein composition was observed. Together, 3DMB is a promising method for tendon tissue engineering, by showing improved fiber and mechanical properties compared to meltblown scaffolds. However, while an improvement on prior iterations, continued development of this 3DMB technology is needed to better mimic the mechanical properties and biologic composition of native tendon.