In vitro and In vivo Performance of Bioabsorbable Scaffolds Suitable for Skin Regeneration

IGNACIO RUIZ; AMELIA NIEVA; ANA GONZÁLEZ WUSENER; GLADYS HERMIDA; CARLOS O. ARREGUI; ALBERTO BOLGIANI; ÉLIDA HERMIDA

Congreso; European Chapter Meeting of the Tissue Engineering and Regenerative Medicine International Society (TERMIS-EU 2013); 2013

Temporary scaffolds for tissue engineering require bioabsorbible materials that degrade into non-toxic substances once the tissue is repaired. Since polyhydroxyalkanoates satisfy these properties, many researchers have focused on them to build up bioabsorbable scaffolds to be harvested with osteoblasts, fibroblasts, vascular cells, among others. Drawbacks of these biopolyesters are their hydrophobic behaviour and the slow bioabsorption rate, which affect negatively the formation of the new tissue. Furthermore, these devices must have suitable mechanical properties to prevent friability, adapt to anatomical contours, facilitate handling by surgeons and, last but not least, a proper surface to enhance the adhesion, motility and proliferation of cells and the interaction with the surrounding tissue. This work shows that proper fabrication processes may allow getting a hydrophilic scaffold with proper biodegradation rate and suitable biomechanical properties for skin regeneration. On one hand, the decrease of the dry weight of samples stored at 37ºC and pH 7.4 in phosphate buffered saline (PBS) and PBS with lipases as well as changes in the molecular weight of PHBV show how the degradation rate depends on the meso-structures and the media. On the other hand, the scaffolds were implanted into excisional wounds on the abdomen of adult Wistar rats to test biological activity in a wound healing model. In some rats the scaffolds accelerated wound healing relative to the blank control; in all cases almost complete healing with reepithelization was achieved at day 10. H&E-stained sections show the absence of inflammatory response, the complete regeneration of the skin and a partial bioabsorption of the scaffold 10 days after implantation.