Spider silk scaffolds

Though, so far relatively sparsely explored, functionalized recombinant spider silk scaffolds for cell culture might provide a broad range of solutions for in vitro cell culture and possibly also for tissue engineering apphcations. 

Gellynck, K., Verdonk, P.C., Van Nimmen, E., Ahnqvist, K.F., Gheysens, T., Schoukens, G., Van Langenhove, L., Kiekens, R, Mertens, J., Verbruggen, G., 2008. Silkworm and spider silk scaffolds for chondrocyte support. Journal of Materials Science Materials in Medicine 19 (11), 3399-3409. 

Although the amino acid sequence as well as the secondary structure of fibroin differs from those of spidroin, the fibers spun from these proteins, that is, silkworm silk and spider silk have comparable mechanical properties. These may be attributed to the structural characteristics, both at the molecular and filament level. The superior mechanical properties of silk-based materials, such as films, coatings, scaffolds, and fibers produced using reconstituted or recombinant silk proteins, are determined by their condensed structures. 

In contrast, spider silk is devoid of sericin and hence does not evoke the same biological or immunological reactions. Thus, spider silk has better biocompatibility and is a preferred biomaterial for suture applications. It has also been studied as a material for regenerative nerve conduits to promote peripheral nerve regeneration [33]. Silk s unique mechanical properties coupled with its ability to be fabricated into different textile structures enable its use in tissue engineering scaffolds that mimic the mechanical properties of native tissues. For example, silk filaments have been converted into a braided rope stracture that acts as a scaffold for the regeneration of anterior cruciate ligaments (ACL) [34]. 

Figure 1. Scaffolds of recombinant spider silk. Upper row photograph of a wet fiber (left) and scanning electron micrograph of a dried fiber (right). Lower row photograph of a wetfoam (left) and scanning electron micrograph of a dried foam (right). All scaffolds were made from the miniature spidroin 4RepCT (see Table 1).

Agapov, I. I., Pustovalova, O. L., Moisenovich, M. M., Bogush, V. G., Sokolova, O. S., Sevasty-anov, V. I., Debabov, V. G., and Kirpichnikov, M. P. (2009). Three-Dimensional Scaffold Made from Recombinant Spider Silk Protein for Tissue Engineering. Dokl. Biochem. Biophys. 426, 127-130. 

Wang, H., Wei, M., Zue, Z., and Li, M. (2009). [Cytocompatibility study of Arg-Gly-Asp-re-combinant spider silk protein/poly vinyl alcohol scaffold] Chinese 23, 747-750. 

To study the effect of CNT and fiber size on cell prohferation, silkworm silk natural micrometer sized fibers, silkworm silk nanofibers with and without CNT and spider silk nanofibers with and without CNT were used. Human chondrosarcoma cells (ATCC HTB94) were maintained in culture using DMEM (Dulbecco s modified Eagle s medium Mediatech) supplemented with 10% fetal bovine serum (FBS), 1% penicillin-streptomycin and 1% L-glutamine. For cell seeding on scaffolds, cells from the tissue culture flasks were trypsinized for 5 minutes at 37 °C, neutralized with DMEM, centrifuged for 5 minutes at 1200 rpm and resuspended in DMEM. A sum of 1000000 cells was seeded per scaffold over 48 hours on a shaker at 37 C. The culture medium was supplemented with ascorbic acid (40 pg/ml) on the first day. The cell-scaffold constructs were maintained in the culture environment and... 

Figure 2.12 shows the morphology of cells after 3, 7 and 14 days on spider silk nanofibers. Figure 2.13 shows the morphology on spider silk nanofibers with 1% CNT. On day 3 the cells were attached to the nanofibrous scaffolds... 

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