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A scaffold was fabricated to synergistically encapsulate living human adipose-derived stem cells (hASCs) and platelet-rich plasma (PRP) based on a vapor-phase sublimation and deposition process. During the process, ice templates were prepared using sterile water as the solvent and were used to accommodate the sensitive living cells and PRP molecules. Under controlled processing conditions, the ice templates underwent vapor sublimation to evaporate water molecules, while at the same time, vapor-phase deposition of poly- p -xylylene (Parylene, USP Class VI highly biocompatible) occurred to replace the templates, and the final construction yielded a scaffold with Parylene as the matrix, with simultaneously encapsulated living hASCs and PRP molecules. Evaluation of the fabricated synergistic scaffold for the proliferation activities toward the encapsulated hASCs indicated significant augmentation of cell proliferation contributed by the PRP ingredients. In addition, osteogenic activity in the early stage by alkaline phosphatase expression and later stage with calcium mineralization indicated significant enhancement toward osteogenetic differentiation of the encapsulated hASCs, which were guided by the PRP molecules. By contrast, examinations of adipogenic activity by lipid droplet formation revealed an inhibition of adipogenesis with decreased intracellular lipid accumulation, and a statistically significant downregulation of adipogenic differentiation was postulated for the scaffold products when compared to the osteogenetic results and the control experiments. The reported fabrication method featured a clean and simple process to construct scaffolds that combined delicate living hASCs and PRP molecules inside the structure. The resultant synergistic scaffold and the selected commercially available hASCs and PRP are emerging as tissue engineering tools that provide multifunctionality for tissue repair and regeneration.

In this study, a porous, three-dimensional material of parylene (poly- p -xylylene) incorporating keratin was fabricated. As an FDA-approved material, parylene is highly stable and biocompatible. Keratin is an abundant natural material that can enhance cell adhesion and wound healing. A unique vapor deposition construction technique dispersed keratin homogenously in the parylene system. Instead of using a conventional template, a sublimating template was applied. This composite porous scaffold was investigated mechanically and biologically. In addition, human adipose stem cells were cultured on the scaffold. The synergistic functions, including biocompatibility, permeability, cell adhesion, and stem cell differentiation, were investigated. A mouse excisional wound-healing model further verified that using the porous composite scaffold with stem cells accelerated the wound healing process, supporting its in vivo efficacy. The positive results demonstrated that this material has the potential to serve as a wound repair platform.