Spider Silk as Guiding Biomaterial for Human Model Neurons

Abstract

Over the last years, a number of therapeutic strategies have emerged to promote axonal regeneration. An attractive strategy is the implantation of biodegradable and nonimmunogenic artificial scaffolds into injured peripheral nerves. In previous studies, transplantation of decellularized veins filled with spider silk for bridging critical size nerve defects resulted in axonal regeneration and remyelination by invading endogenous Schwann cells. Detailed interaction of elongating neurons and the spider silk as guidance material is unknown. To visualize direct cellular interactions between spider silk and neurons in vitro, we developed an in vitro crossed silk fiber array. Here, we describe in detail for the first time that human (NT2) model neurons attach to silk scaffolds. Extending neurites can bridge gaps between single silk fibers and elongate afterwards on the neighboring fiber. Culturing human neurons on the silk arrays led to an increasing migration and adhesion of neuronal cell bodies to the spider silk fibers. Within three to four weeks, clustered somata and extending neurites formed ganglion-like cell structures. Microscopic imaging of human neurons on the crossed fiber arrays in vitro will allow for a more efficient development of methods to maximize cell adhesion and neurite growth on spider silk prior to transplantation studies.

Characterization and Schwann Cell Seeding of up to 15.0 cm Long Spider Silk Nerve Conduits for Reconstruction of Peripheral Nerve Defects

“…Recently, it was reported that spider silk served as guidance material for human model neurons in vitro and that spider silk enhanced the development of ganglion like structures within one month [33]. Previously it was shown that NIH/3T3-fibroblasts can grow on spider silk and lead to a dense network on the woven spider silk frames [34].…”

Spider Silk for Tissue Engineering Applications

“…Almelling et al and Roloff et al [42,43] collected dragline silk from Nephila species on frames with 20 to 30 fibers in parallel orientation and used this as a scaffold for guiding human model neurons. Neuronal cell bodies contacted the spider silk fibers, and ganglion-like structures were formed within four weeks.…”

Silk‐Based Biomaterials in Biomedical Textiles and Fiber‐Based Implants

“…Tang et al (2009) also demonstrated SF fiber nerve scaffolds with feasibility as CNS substitutes due to good biocompatibility when studied with primary cultured hippocampal neurons [135] . Roloff et al (2014) developed an in vitro crossed silk fiber array to visualize direct cellular interactions between spider silk and neurons in vitro [136, 137] . Silk films were used to modulate the conductance of astroglia and sacrificial silk fibroin films (dissolution times of 15–20 min) were used for neural interfaces [138] .…”