Pediatric MSC-AFP Sub-study for Crohn's Fistula

Inclusion Criteria 1. Males and females 12-17 years of age. 2. Residents of the United States. 3. Crohn's disease with single or multiple draining complex perianal fistulae (definition as below) for at least three months despite standard therapy (definition below). 4. Concurrent therapies with corticosteroids, 5-aminosalicylate (5-ASA) drugs, thiopurines, methotrexate (MTX), antibiotics, and anti-tumor necrosis factor (TNF) therapy are permitted. 5. All patients should have undergone a colonoscopy in last 12 months to rule out malignant or premalignant condition 6. Have no contraindications to MR evaluations: e.g. pacemaker or magnetically active metal fragments, claustrophobia 7. Ability to comply with protocol 8. Competent and able to provide written informed consent (and assent where appropriate). 9. Must have failed standard medical therapy including anti-TNF agents Exclusion Criteria 1. Inability to obtain informed consent (and assent where appropriate). 2. Clinically significant medical conditions within the six months before administration of MSCs: e.g. sepsis, pneumonia active serious infection or other conditions that would, in the opinion of the investigators, compromise the safety of the patient. 3. Specific exclusions; a. Evidence of hepatitis B, C, or HIV 4. History of cancer including melanoma (with the exception of localized skin cancers) 5. Investigational drug within thirty (30) days of baseline 6. A resident outside the United States 7. Pregnant or trying to become pregnant, or breast feeding. 8. History of clinically significant auto-immunity (other than Crohn's disease) or any previous example of fat-directed autoimmunity 9. Previous allergic reaction to a perianal fistula plug. 10. If adipose tissue is not technically feasible 11. Weight less than 35 kg 12. Allergic to local anesthetics 13. Non-enterocutaneous tracts (i.e. recto-vaginal, entero-vesicular)