Expanded Access - Autologous Human Schwann Cells in Peripheral Nerve Repair

Inclusion Criteria: * Persons with severe sciatic nerve injury, brachial plexus injury, and/or major injury at the upper or lower extremity with nerve loss within previous year; * Peripheral nerve injury with large gap (5 - 10 cm) between healthy nerve endings; Exclusion Criteria: * Persons unable to safely undergo an MRI (may include persons with an implanted device or metallic fragments which may interfere with MRI safety); * Persons with pre-existing conditions that would preclude satisfactory sural nerve harvest (may include amputation or major injury to lower limb, or disease affecting the sural nerve); * Persons with severe peripheral nerve injury gap length \> 10 cm in length; * Persons with history of radiation or local cancer in area of nerve injury, including primary tumors of the nerve; * Pregnant women or a positive pregnancy test in those women with reproductive potential prior to transplantation; * Presence of disease that might interfere with participant