Engineering three-dimensional nervous tissue constructs based on fiber-gel substrates

Three-dimensional (3D) nervous tissue constructs were developed using a compliant gel matrix and a fiber component for promoting contact-guided axon outgrowth. Rat embryonic (E15) dorsal root ganglion expiants (DRGs) were cultured on biodegradable poly-L-lactic acid (PLLA) and wet-spun type I collagen fibers embedded in soft collagen gels. Gel constructs containing fibers induced greater axon outgrowth distances with significantly more directionality along the aligned fibers. Interestingly, wet-spun type I collagen from rat tail tendon displayed a highly aligned outgrowth pattern from DRG axons suggesting potential use for peripheral nerve repair.