Investigation of the properties and potential medical applications of natural silk fibers produced by Eupackardia calleta

Silk has been considered biocompatible and used for medical applications for centuries. However, most of the silk currently used is produced by the domesticated silkworm, Bombyx mori. Recently, it has been demonstrated that silk produced by saturniidae insects such as Antheraea mylitta, Phylisomia ricini, and Antheraea pernyi had unique properties and suitable for medical applications. Therefore, efforts are being made to identify and study the structure and properties of silks produced by wild insects (non B. mori), spiders, and ants to understand their suitability for various medical applications. Eupackardia calleta belongs to the Saturniidae family of insects, but the structure, properties, and potential medical uses of silk fibers produced by E. calleta are not known. In this research, we have characterized the properties of silk fibers produced by E. calleta and the ability of the fibers to support the attachment and proliferation of mouse fibroblast cells. Silk produced by E. calleta had considerably different amino acid composition than B. mori and A. mylitta, P. ricini, and A. pernyi silks. Breaking tenacity of the E. calleta silk fibers at 400 MPa was between that of B. mori silk and A. mylitta, P. ricini, and A. pernyi silks. E. calleta showed good attachment and spreading of mouse fibroblast cells suggesting potential for medical applications.