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Spider silk (SPSI) is a promising candidate for use as a filler material in nerve guidance conduits (NGCs), facilitating peripheral nerve regeneration by providing a scaffold for Schwann cells (SCs) and axonal growth. However, the specific properties of SPSI that contribute to its regenerative success remain unclear. In this study, the egg sac silk of Trichonephila (T.) inaurata is investigated, which contains two distinct fiber types: tubuliform (TU) and major ampullate (MA) silk. These fibers serve as models to derive material parameters governing SC migration on natural silk substrates, since they are produced by the same spider, yet exhibiting distinct composition and morphology. In this paper, detailed characterization of the fibers’ material properties and in vitro evaluation of their SC-guiding performance were conducted. Live cell imaging revealed significantly enhanced SC mobility and directionality on TU silk compared to MA silk, which is remarkable, given the lack of studies on TU silk for nerve regeneration. Our results suggest that the distinct morphological and material properties of these fibers are critical to their nerve-guiding potential. These insights contribute to the optimization of NGC filler materials by identifying key parameters essential for effective nerve regeneration.
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Comparative Analysis of Various Spider Silks in Regard to Nerve Regeneration: Material Properties and Schwann Cell Response
Peripheral nerve reconstruction through the employment of nerve guidance conduits with Trichonephila dragline silk as a luminal filling has emerged as an outstanding preclinical alternative to avoid nerve autografts. Yet, it remains unknown whether the outcome is similar for silk fibers harvested from other spider species. This study compares the regenerative potential of dragline silk from two orb‐weaving spiders, Trichonephila naurata and Nuctenea umbratica, as well as the silk of the jumping spider Phidippus regius. Proliferation, migration, and transcriptomic state of Schwann cells seeded on these silks are investigated. In addition, fiber morphology, primary protein structure, and mechanical properties are studied. The results demonstrate that the increased velocity of Schwann cells on Phidippus regius fibers can be primarily attributed to the interplay between the silk's primary protein structure and its mechanical properties. Furthermore, the capacity of silk fibers to trigger cells toward a gene expression profile of a myelinating Schwann cell phenotype is shown. The findings for the first time allow an in‐depth comparison of the specific cellular response to various native spider silks and a correlation with the fibers’ material properties. This knowledge is essential to open up possibilities for targeted manufacturing of synthetic nervous tissue replacement.
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- PAR ID:
- 10527897
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 13
- Issue:
- 8
- ISSN:
- 2192-2640
- Subject(s) / Keyword(s):
- Tissue Engineering, Biomaterials, Migration, Mechanical Properties, Morphology, Transcriptomics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/adhm.202302968
