gms | German Medical Science

Spider silk is one of the most promising biomaterials with effects not only in nerve regeneration but generally in regenerative applications. The development of this material for human applicability is of tremendous scientific and clinical interest. Biomaterials in use for biomedical applications have to meet a number of requirements like biocompatibility and a mild inflammatory response, biodegradability in a reasonable time and specific structural properties. These demands are perfectly met by the biomechanical and biomedical characteristics of native spider silk.

Cross-woven spider silk fibers can provide a model framework for adherent cell growth, which we used to study cellular reactions on spider silk. Skin cells were seeded on the silk scaffolds and kept in short-term and long-term culture showing metabolic activity and high vitality rates. Schwann cells adhered also sufficiently on native spider silk fibers with high vitality rates excluding any toxic or harmful effects on the cells. A nerve conduit was developed based on these data consisting of spider silk fibers aligned within a decellularized vein in which the supplemented Schwann cells aligned along the fibers.

Several groups are currently working with spider silk as material for tissue engineering. The silk is being used in different forms, e.g. natural occurring silk or in form of silk fibroins and potential application in clinical used are being explored. Natural occurring spider silk has been shown to be advantageous for cell attachment. Cell vitality and proliferation after in vitro seeding with fibroblasts could be demonstrated. Spider silk as used by our group, did not induce an inflammatory foreign body response when used nor result in nonphysiological pH changes, which could inhibit tissue regeneration. The use of silk fibroin proteins, however, is a basically different approach to the use of spider silk as technically processed material is used instead of native biomaterial. This difference stand for advantages as for disadvantages as well as the processing allows for technical adaption like tube formation by gel spinning or combination with other materials but might also be more reliant on modifications to enhance cytocompatibility than native spider silk.

Spider silk is a biopolymer with a huge number of possible technical and biomedical applications. For several inventions prototype status could be achieved, while most ideas are still of speculative nature. Here we present current status of the research in this field and discuss current advances with regard to potential clinical transfer.