Inclusion Criteria:
1. Ability to understand the purpose and risks of the study and provide signed and dated informed consent and authorization to collect and use protected health information (PHI) in accordance with national and local subject privacy regulations.
2. Live within reasonable travel distance to center or have reliable mechanism to travel to the center.
3. Have a caregiver willing/able to assist in the transportation and care required by study participation.
4. Subject is 18 - 70 years of age (inclusive) on day of Screening Visit.
5. Subject is diagnosed with idiopathic TM within the past 120 months in accord with the Transverse Myelitis Consortium Working Group (2002).
6. Subject has an MRI with a single focus of T2 hyperintensity with its most rostral extent at or below C8 myotome/dermatome level.
7. Subject has negative NMO IgG (anti-AQP4) test at two separate time points, separated by at least 6 months.
8. Subject has brain MRI not consistent with multiple sclerosis or other autoimmune or demyelinating disease.
9. Subject is more than 12 months from TM onset.
10. Subject has ASIA A, B or C categorization, and is unable to ambulate (Cohort A) or unable to ambulate 100 feet without significant bilateral support. (Cohort B).
11. Subject's neurological deficits related to TM have been stable for at least 3 months.
12. Subject is medically able to undergo the study procedures and physically able to adhere to the visit schedule at the time of study entry.
13. For women of child bearing capacity, negative pregnancy test during the Screening Period and at the Pre-Operative Visit.
14. Males and females will agree to practice effective birth control during study participation and up to one year after.
15. Current, up to date, COVID vaccination.
16. Current, up to date, varicella zoster vaccination.
17. Current, seasonally up to date, influenza vaccination.
Exclusion Criteria:
1. Subject with causes of weakness, sensory loss and/or autonomic dysfunction other than TM have not been practically excluded.
2. Subject with significant cognitive impairment, clinical dementia, or major psychiatric illness including psychosis, bipolar disease, major depression, as determined by the DSM-V that will interfere with participation in the trial.
3. Subject with a diagnosis of a neurodegenerative disease (e.g., ALS, Parkinson's disease, Alzheimer's disease).
4. Subject suffering with medical conditions that impair nerve or muscle function (e.g., notable peripheral neuropathy, metabolic muscle disease) or any disease or condition that would impair the subject's neuromuscular function or impair the adequate assessment of the subject's function (e.g., severe osteoarthritis).
5. Subject with a clinically significant history of unstable cardiac, pulmonary, renal, hepatic, endocrine, hematologic, or active malignancy or infectious disease or other medically significant illness that may render them at an unacceptable risk for surgery or that may cause them to be unable to complete the scheduled duration of the trial.
6. History of spine surgery or anatomic variation incompatible with route of administration (as determined by neurosurgeon).
7. Severe spinal stenosis or cord compression causing myelopathy.
8. Abnormal flow voids on the surface of the spinal cord suggestive of arteriovenous malformation (AVM) or evidence of a vascular cause of a myelopathy (e.g., infarct of spinal artery).
9. Any evidence of CNS malignancy or clinically significant CNS lesions as defined by imaging studies of the CNS (MRI of brain and spinal cord).
10. Uncontrolled hypertension (Systolic BP\>180mmHg and/or Diastolic BP \>110mmHg).
11. Any poorly controlled medical conditions that, in the opinion of the site investigator and/or surgeon, increase risk of surgery to a medically unacceptable degree.
12. Subjects who cannot undergo MRI examination because of any contraindication to the procedure, including the presence of a pacemaker, an implanted defibrillator or certain other implanted electronic or metallic devices, or who have been or might have been exposed to metal fragments, or any reason the subject cannot undergo an MRI routinely for the duration of the trial.
13. Subject with clinically significant abnormal clinical laboratory values, as determined by the Investigator at the screening visit (Visit 1).
14. Subject who is immune compromised (by therapeutic agent or disease) or who has a condition contraindicated to treatment with immunosuppression agents (e.g., tuberculosis, latent infection) as determined by history or testing. Any subject with an ongoing infection until it has been adequately treated and it is deemed to be resolved.
15. Subject with aspartate aminotransferase (AST) or alanine aminotransferase (ALT) value \>3.0 times the upper limit of normal at the screening visit (Visit 1).
16. Subject with diabetes or HgbA1c \> 6.5.
17. Subject with a history of alcohol or drug abuse or dependence within 1 year of screening visit (Visit 1), per DSM-V criteria.
18. Subject unlikely to comply with study requirements, as determined by Investigator.
19. Subject who has been exposed to any other experimental agent (off-label use or investigational) within 60 days of screening visit (Visit 1). Biologic agents may need additional time for washout and will be evaluated by the Sponsor on a case-by-case basis.
20. Subject with pre-existing severe or high titer anti-human leukocyte antigen (HLA) class I or class II antibodies directed against the Q-Cells®, as determined by panel reactive antibody (PRA) assay.
21. Allergy to study treatment (Q-Cells®) or any of its constituents (e.g., chicken eggs), or allergy to any of the co-administered immunosuppressants or any of their excipients.
22. Subject with any medical condition or using concomitant medication that would contraindicate the use of tacrolimus, mycophenolate mofetil, or prednisone as determined by Investigator.
23. Subject has undergone stem cell transplantation (including T-cell or bone marrow transplants) at any time prior to study (within or outside the US).
24. Subject with prior embolus or evidence of deep vein thrombosis (DVT) by venous ultrasound without adequate treatment.
25. Subject has recent (1 year) or recurrent history of gastrointestinal bleeding or peptic ulcer disease or is under active treatment to prevent recurrence.
26. Subject with estimated glomerular filtration rate at screening of less than 60 mL/min/1.73m2.
27. Subjects with hereditary deficiency of hypoxanthine-guanine phosphoribosyl-transferase (HGPRT) such as Lesch-Nyhan and Kelley-Seegmiller syndrome.
28. Vaccination with live virus within 6 weeks of screening.
29. History or evidence of optic neuritis.
30. Any reason, in the judgment of the investigator, which would make the subject inappropriate for entry into this trial.
