Structural and rheological characterization of hyaluronic acid-based scaffolds for adipose tissue engineering

In this study the attention has been focused on the ester derivative of hyaluronic acid (HA), HYAFF®11, as a potential 3D scaffold in adipose tissue engineering. Different HYAFF®11 sponges having different pore sizes, coated or not coated with HA, have been studied from a rheological and morphological point of view in order to correlate their structure to the macroscopic and degradation properties both in vitro and in vivo, using rat model. The in vitro results indicate that the HYAFF®11 sponges posses proper structural and mechanical properties to be used as scaffolds for adipose tissue engineering and, among all the analysed samples, uncoated HYAFF®11 large pore sponges showed a longer lasting mechanical stability. From the in vivo results it was observed that the elastic modulus of scaffolds seeded with pre adipocytes, the biohybrid constructs, and explanted after 3 months of implantation in autologous rat model are over one order of magnitude higher than the corresponding value for the native tissue. These results could suggest that the implanted scaffolds can be invaded and populated by different cells, not only adipocytes, that can produce new matrix having different properties from that of adipose tissue.