PLGA/Gelatin/Hyaluronic Acid Fibrous Membrane Scaffold for Therapeutic Delivery of Adipose-Derived Stem Cells to Promote Wound Healing.

Hyaluronic acid (HA) has been suggested to be a preferential material for the delivery of adipose-derived stem cells (ASCs) in wound healing. By incorporating HA in electrospun poly (lactide-co-glycolide) (PLGA)/gelatin (PG) fibrous membrane scaffolds (FMS), we aim to fabricate PLGA/gelatin/HA (PGH) FMS to provide a milieu for 3D culture and delivery of ASCs. The prepared FMS shows adequate cytocompatibility and is suitable for attachment and growth of ASCs. Compared with PG, the PGH offers an enhanced proliferation rate of ASCs, shows higher cell viability, and better maintains an ASC-like phenotype during in vitro cell culture. The ASCs in PGH also show upregulated expression of genes associated with angiogenesis and wound healing. From a rat full-thickness wound healing model, a wound treated with PGH/ASCs can accelerate the wound closure rate compared with wounds treated with PGH, alginate wound dressing, and gauze. From H&E and Masson's trichrome staining, the PGH/ASC treatment can promote wound healing by increasing the epithelialization rate and forming well-organized dermis. This is supported by immunohistochemical staining of macrophages and α-smooth muscle actin, where early recruitment of macrophages, macrophage polarization, and angiogenesis was found due to the delivered ASCs. The content of type III collagen is also higher than type I collagen within the newly formed skin tissue, implying scarless wound healing. Taken together, using PGH FMS as a topical wound dressing material for the therapeutic delivery of ASCs, a wound treated with PGH/ASCs was shown to accelerate wound healing significantly in rats, through modulating immunoreaction, promoting angiogenesis, and reducing scar formation at the wound sites.