Umbilical Cord Blood Cell (MC001) Transplant Into Injured Spinal Cord Followed by the Locomotor Training

Inclusion Criteria: * Male and female subjects' ≥18 to ≤60 years. * Traumatic SCI at a neurological level (the lowest contiguous spinal cord segmental level that has intact motor and sensory score) between C5 and T11 by MRI. Note: For the first three subjects at each study center, the neurological level of SCI will be limited to thoracic region (between T1 and T11). * Subjects with chronic SCI (defined as ≥ 12 months post- initial SCI surgery) with stable neurologic findings for at least six months and be able stand at least 1 hour/day using a standing frame, tilt table, or equivalent device. * Subjects with a current neurological status of ASIA impairment grade A (complete). * The injured site of the spinal cord is within three vertebral levels as confirmed by MRI scan. * Subject must be in good enough physical health to tolerate the surgery and participate in the intensive walking program. * Clinically normal resting 12-lead ECG at Screening Visit or, if abnormal, considered not clinically significant by the Principal Investigator. * Both male and female subjects and their partners of childbearing potential must agree to use medically accepted methods of contraception. * Willing and able to participate in all aspects of the study, including completion of subjective evaluations, attendance at scheduled clinic visits, and compliance with all protocol requirements as evidenced by providing written informed consent. * At least one frozen HLA-matched (≥4:6 to a specific patie…