Engineering of fibrillar decorin matrices for a tissue-engineered trachea

Decorin is a structural and functional proteoglycan (PG) residing in the complex network of extracellular matrix (ECM) proteins in many connective tissues. Depending on the protein core and the glycosaminoglycan chain, PGs support cell adhesion, migration, proliferation, differentiation, ECM assembly and growth factor binding. For applications in tissue engineering, it is crucial to develop reliable, ECM-mimicking biomaterials. Electrospinning is a suitable method for creating three-dimensional (3D), fibrillar scaffolds. While there are numerous reports on the electrospinning of proteins including collagen, to date, there are no reports on the electrospinning of PGs. In the following study, we used electrospinning to generate decorin-containing matrices for tracheal tissue engineering applications. The electrospun scaffolds were analyzed using scanning electron microscopy, atomic force microscopy, contact angle measurements and dynamic mechanical analysis. Additionally, we confirmed PG functionality with immunostaining and 1,9-dimethylmethylene blue. To determine cell-matrix-interactions, tracheal cells (hPAECs) were seeded and analyzed using an FOXJ1-antibody. Moreover, interactions of the electrospun scaffolds with immune-mediated mechanisms were analyzed in detail. To conclude, we demonstrated the feasibility of electrospinning of decorin to generate functional 3D scaffolds with low immunogenicity for hPAEC expansion. Our data suggest that these hybrid materials may be suitable as a substrate for tracheal tissue engineering.