Robotic winding of wet-spun fibers for biofabrication of aligned, perfusable, muscle-based tissue

Structural alignment of muscle and integrated vasculature enables the function of geometrically complex tissues in the body, such as the gastroesophageal junction and the ventricles. However, replicating this complexity is an ongoing challenge. Described here is the wet-spun & robotically articulated placement (WRAP) method for deposition of aligned cellular fibers on scaffolds, resulting in large structures fabricated from the inside-out. WRAP enables complex, multi-oriented muscle and vascular placement by creating a continuous cellular fiber through wet spinning, and then using a robotic arm programmed with a set of tissue profiles to maneuver the fiber around an organ scaffold. Wet-spun fibers, consisting of muscle cells combined with endothelial cell fibers via double-core spinning, exhibited the ability to mature, align, contract, and initiate tubulogenesis, creating perfusable fibers. Further, the robotic arm could accurately create physiologically relevant fiber patterns with high precision. The potential to generate perfusable blood vessels alongside functional muscle is paramount to fabricating muscle-based constructs. The WRAP method offers a high throughput and versatile solution to the scale-up problem plaguing the biofabrication of muscle-based tissues.