A Comparative Analysis of the Structure and Biological Properties of Films and Microfibrous Scaffolds Based on Silk Fibroin

A comparative analysis of the structure and biological properties of silk fibroin constructions was performed. Three groups of constructions were obtained: films obtained by casting an aqueous solution of silk fibroin and electrospun microfibrous scaffolds based on silk fibroin, with the addition of 30% gelatin per total protein weight. The internal structures of the films and single fibers of the microfibrous scaffolds consisted of densely packed globule structures; the surface area to volume ratios and volume porosities of the microfibrous scaffolds were calculated. All constructions were non-toxic for cells and provide high levels of adhesion and proliferation. The high regenerative potential of the constructions was demonstrated in a rat full-thickness skin wound healing model. The constructions accelerated healing by an average of 15 days and can be considered to be promising constructions for various tasks of tissue engineering and regenerative medicine.

The effect of biodegradable silk fibroin-based scaffolds containing glial cell line-derived neurotrophic factor (GDNF) on the corneal regeneration process

Corneal injury due to ocular trauma or infection is one of the most challenging vision impairing pathologies. The aim of the work was to study the effect of biodegradable silk fibroin-based scaffolds containing GDNF on the corneal regeneration process. During cultivate the highest keratocytes proliferative activity was registered with scaffolds containing 250 ng/ml and 500 ng/ml GDNF. In mice with an experimental model of epithelial-stromal damage to the cornea, silk fibroin-based scaffolds containing GDNF in various concentrations were used (in groups 1, 2 and 3 silk fibroin-based scaffolds containing GDNF in a concentration of 50 ng/ml, 250 ng/ml and 500 ng/ml, respectively; in group 4 - silk fibroin-based scaffolds without GDNF; in group 5 - a solution of GDNF with concentration of 500 ng/ml; group 6- control). The area of the corneal epithelial defect in groups 2, 3, and 5 was less than in the other groups. The most pronounced positive immunohistochemical reaction with antibodies to Bcl2, Bax, phosphoERK1/2 and phospho-JNK1/2, Ki67, Gap43 was observed in groups 2 and 3. Thus, silk fibroin-based scaffolds with GDNF stimulate the epithelialization process, proliferative activity of epithelial cells and keratocytes, accelerate the formation of the stromal nerve plexus and exhibit anti-apoptotic activity.