The investigators' preliminary study indicates that MSC is effective therapy in treating IBD. But the standard treatment is still lacking and the effect is not stable in IBD patients. This study is to explore the efficacy and standard strategy when using MSC in refractory IBD.

Inclusion Criteria:

• Failure or intolerance to GC, immune inhibitors and biological agents treatment
• CDAI between 250-450
• Weight between 40-150 kg
• Normal renal function
• endoscopic or imaging diagnosis of CD in the small intestine, colon ileocolon
• Signed informed consent

Exclusion Criteria:

• HIV or active hepatitis patients;
• Allergic to CT contrast agents, cattle or pig products;
• Stricture or perforation type CD;
• Recieved permanent colostomy;
• Used biological preparation in 3 months
• Used prednisone > 20 mg/day within 1 month ;
• Patients with short bowel syndrome;
• Need total parenteral nutrition;
• Liver meritorious service is abnormal;
• Suffering from malignant tumor during the last 5 years;
• Combined bacterial or viral enteritis;
• Suffering from intestinal typicality thickening of the living
• Patients with tuberculosis.