Plasma-Activated Substrate with a Tropoelastin Anchor for the Maintenance and Delivery of Multipotent Adult...

Conventional wound therapy utilizes wound coverage to prevent infection, trauma, and fluid and thermal loss. However, this approach is often inadequate for large and/or chronic wounds, which require active intervention via therapeutic cells to promote healing. To address this need, a patch which delivers multipotent adult progenitor cells (MAPCs) is developed. Medical-grade polyurethane (PU) films are modified using plasma immersion ion implantation (PIII), which creates a radical-rich layer capable of rapidly and covalently attaching biomolecules. It is demonstrated that a short treatment duration of 400 s maximizes surface activation and wettability, minimizes reduction in gas permeability, and preserves the hydrolytic resistance of the PU film. The reactivity of PIII-treated PU is utilized to immobilize the extracellular matrix protein tropoelastin in a functional conformation that stably withstands medical-grade ethylene oxide sterilization. The PIII-treated tropoelastin-functionalized patch significantly promotes MAPC adhesion and proliferation over standard PU, while fully maintaining cell phenotype. Topical application of the MAPC-seeded patch transfers cells to a human skin model, while undelivered MAPCs repopulate the patch surface for subsequent cell transfer. The potential of this new wound patch as a reservoir for the sustained delivery of therapeutic MAPCs and cell-secreted factors for large and/or non-healing wounds is indicated in the findings.