Micro- and nano-environment dual-modulated anti-tendon adhesion barrier membranes

Despite promise in preventing peritendinous adhesion, electrospun membranes face many challenges related to their complex fabrication process, untargeted/uncontrolled drug delivery and consequently low therapeutical effect. Here, a micro-and nano-environment dual-modulated barrier membrane (MNBM) with on-demand gene delivery capability is presented. Our MNBM is developed by first preparing extracellular signal-regulated kinase-2 (ERK2) siRNA-loaded gelatin methacryloyl (GelMA) nanogels via facile nano-emulsification technique, then incorporating these nanogels into poly-L-lactic acid (PLLA) fibers via simple blending electrospinning. The GelMA nanogels offer a nano-niche for ERK2-siRNA encapsulation and allow for a nano-environment controlled siRNA release by readily tuning the GelMA concentrations during nano-emulsification, while the resultant MNBM can mediate a micro-environment controlled siRNA delivery in response to the matrix metalloproteinase-2 (MMP-2) enriched micro-environment at the tendon repair site. Such MNBM can not only biologically orchestrate fibroblast behaviors by silencing the target gene expression, but also physically shield the tendon from extrinsic cell/tissue invasion. This study provides a proof-of-concept of anti-adhesion barrier membrane as an intelligent gene delivery system to offer a spatiotemporal and biophysical dual control over tendon recovery according to disease state and ensure long-term therapeutic efficacy. We envision such MNBM represents a promising therapeutic platform with great efficacy to achieve adhesion-free tendon repair.