The investigators propose to study the safety of autologous mesenchymal stromal cell transfer using a biomatrix (the Gore® Bio-A®; Fistula Plug) in a Phase I study using a single dose of 20 million cells. Twenty adult patients (age 18 years or older) with refractory, complicated perianal fistulizing Crohn's disease will be enrolled. Subjects will undergo standard adjuvant therapy including drainage of infection and placement of a draining seton with continuation of pre-existing anti-Crohn's therapy. Six weeks post placement of the draining seton, the seton will be replaced with the MSC loaded Gore® Bio-A® fistula plug as per current clinical practice. The subjects will be subsequently followed for fistula response and closure for 24 months. This is an autologous product derived from the patient and used only for the same patient.

Inclusion Criteria

• Males and females 18-65 years of age.
• Residents of the United States.
• Crohn's disease with single or multiple draining complex perianal fistulae (definition as below) for at least three months despite standard therapy (definition below).
• Concurrent therapies with corticosteroids, 5-ASA drugs, thiopurines, MTX, antibiotics, and anti-TNF therapy are permitted.
• All patients should have undergone a colonoscopy in last 12 months to rule out malignant or premalignant condition
• Have no contraindications to MR evaluations: e.g. pacemaker or magnetically active metal fragments, claustrophobia
• Ability to comply with protocol
• Competent and able to provide written informed consent
• Must have failed standard medical therapy including anti-TNF agents

Exclusion Criteria

• Inability to give informed consent.
• Clinically significant medical conditions within the six months before administration of MSCs: e.g. myocardial infarction, active angina, congestive heart failure or other conditions that would, in the opinion of the investigators, compromise the safety of the patient.
• Specific exclusions: Evidence of hepatitis B, C, or HIV
• History of cancer including melanoma (with the exception of localized skin cancers)
• Investigational drug within thirty (30) days of baseline
• A resident outside the United States
• Pregnant or breast feeding.
• History of clinically significant auto-immunity (other than Crohn's disease) or any previous example of fat-directed autoimmunity
• Previous allergic reaction to a perianal fistula plug.
• If liposuction is not technically feasible
• Allergic to local anesthetics
• Pregnant patients or trying to become pregnant.
• Non-enterocutaneous tracts (ie recto-vaginal, entero-vesicular)