Regenerative abilities of a nanofiber wound dressing based on polylactide.

Introduction: The development of an ideal dressing for wound healing remains an unresolved issue. Thanks to the development of electrospinning technology, polymers in the form of nanofibers have come to the forefront of research interest. A modern and very promising dressing material is a “nonwoven” based on nanofibers of the synthetic polymer polylactide (PLA). The aim of this work was to assess the regenerative abilities of PLA in a standardized wound in a porcine model and compare our results to the literature data.

Methods: We applied PLA-based nanofiber dressings to the standardized wounds created in the porcine model. On the third, tenth, seventeenth and twenty-fourth days after the formation of the defect, we changed the wound dressing while taking a tissue sample for histopathological examination. We continuously monitored serum levels of acute phase proteins.

Results: PLA stimulated an inflammatory response. From the third day, the thickness of the fibrin layer with granulocytes increased. It reached its maximum values on the tenth day (mean 340 μm); at the same time the level of serum amyloid A, as a marker of inflammation, culminated. The individual phases of healing intertwined. The highest thickness values of the granulation tissue with cellular connective tissue (diameter 8463 μm) were reached on the seventeenth day. On the twenty-fourth day, the defects were healed macroscopically with a mean reepithelialization layer of 9913 μm.

Conclusion: PLA-based nanofiber dressing potentiates the inflammatory, proliferative and reepithelialization phases of healing. Its structure perfectly mimics the extracellular matrix and serves as a 3D network for the growth and interaction of cellular elements. In addition to biocompatibility, PLA has a unique ability of two-phase biodegradation. It is a promising material for industrial production of dressing materials. Most of the available studies were performed in vitro. In vivo comparative studies approximating the use of PLA to daily practice are still missing.