Aggregation of orientated materials from viscous fibronectin gels for CNS tissue engineering

Fibronectin materials prepared from human plasma have been used in various forms as substrates for tissue engineering. Such purposes require that the soluble protein aggregates into insoluble fibrous structures which encourage the attachment and migration of cells. The method of aggregation due to mechanical shear was investigated by applying fluid shear forces directly to a viscous solution of Fn. Structural analysis revealed that mechanical shear resulted in the formation of an orientated fibrous protein structure that was less soluble than its non-sheared counterpart. The suitability of this shear aggregated Fn material for CNS repair purposes was assessed in vitro where it supported the growth of three cell types. Implantation of the shear aggregated Fn material into a rat model of spinal cord injury provided a permissive environment for axonal growth.