Intrinsic Vascularization of Recombinant eADF4(C16) Spider Silk matrices in the AV Loop Model.

INTRODUCTION: The surgically induced angiogenesis by means of arteriovenous loops (AV loops) represents a powerful method to significantly enhance vascularization of biomaterials. Concerning Tissue Engineering applications, spider silk is a promising biomaterial with a good biocompatibility and slow biodegradation. The current study aims at investigating vascularization as well as de novo tissue formation of fibrous matrices made of electro- or wet-spun engineered ADF4(C16) spider silks in the rat AV loop model.

MATERIALS AND METHODS: Either electro- or wet-spun spider silk fibrous matrices were filled into Teflon chambers. Intrinsic vascularization was induced by means of an AV Loop. After 4 weeks vascularization, de novo tissue formation and biocompatibility were analyzed.

RESULTS: Regardless of their significantly differing fiber diameters, both electro- and wet-spun eADF4(C16) fiber matrices displayed a good biocompatibility and initiated de novo tissue formation as well as vessel formation. Both matrices demonstrated partial vascularization originating from the AV loop, with more vessels in spider silk matrices with lower fiber diameters.

CONCLUSION: We were able to demonstrate intrinsic vascularization of spider silk fibrous matrices by means of the AV loop. Moreover, our study indicates that the adjustment of the fiber diameter of engineered spider silks enables new possibilities to optimize vascularization.