515 A Novel Hand-Held Bioprinter Enhances Skin Regenration and Wound Healing in a Burn Porcine Model

Skin regeneration after a severe burn injury is crucial for survival. Current treatment options are limited. Mesenchymal Stem Cells (MSCs) are known to promote wound healing and tissue regeneration but delivery of these cells remains a challenge. Bioprinting represents a promising delivery strategy. We have designed, validated in vitro as well as in a large animal wound healing model a novel intraoperatively usable hand-held bio-printer, that delivers MSCs directly and conformally onto wounds, embedded within an extracellular matrix layer. Aim: Determine postburn skin wound regeneration after MSC deposition with a novel intraoperatively usable bioprinter. We conducted a study in a full-thickness porcine burn wound model where we in situ delivered umbilical cord mesenchymal stem cells (UC-MSC) conformally via our hand-held bio-printer. An acellular collagen-based dressing that is the clinical gold standard was seeded with MSC and used as a control. Wound healing and skin regeneration were determined at day 28 (remodeling) and followed until day 49 (maturation) post-intervention for full tissue remodeling assessment. Our data (day 28) show accelerated wound healing after stem cell application, with significantly increased collagen regeneration (