Sustained release of plasmid DNA from PLLA/POSS nanofibers for angiogenic therapy

Angiogenesis plays a critical role to provide a desired microenvironment during tissue repair and regeneration. Gene-activated scaffold is increasingly showing potential in tissue engineering and regenerative medicine. Herein, functional polyhedral oligomeric silsesquioxane (POSS) nanoparticles, known for the organic-inorganic structure and biocompatibility, were incorporated into poly(L-lactic acid) (PLLA) matrix and processed by electrospinning into nanofibers as a delivery vehicle of plasmid DNA encoding angiopoietin-1 (pAng). The introduction of functional POSS nanoparticles increased the strength and toughness of the matrix simultaneously, and formed the porous fiber structure. PAng released from the nanofibrous scaffold showed sustained delivery over 35 days and maintained high transfection efficiency. A full-thickness skin wound model was used to evaluate the pAng delivery efficacy and angiogenesis capability of the plasmid DNA-based polymeric scaffold in vivo. The results indicated that the pAng loaded PLLA/POSS scaffold effectively promoted angiogenesis and dermal wound healing.