The purpose of this study is to determine whether umbilical cord Mesenchymal Stem Cells of treatment for diabetic foot is safe and effective in the management of diabetic foot ischemia, the therapeutic effect of stem cells is caused by improving blood circulation in ischemic limb which would in turn promote ulcer healing, prevent amputation of limb and relieve the Sevier pain of ischemia.

Type 2 diabetic patients with diabetic foot were enrolled and randomized to either transplanted group or control group. Patients in transplanted group received the stem cells treatment,Patients in control group received the standard treatment. After culture in vitro, umbilical cord mesenchymal stem cells should go through safety evaluation which include culture and check of pathogenic microorganisms (bacteria, mycoplasma, chlamydia, eumycete and viruses) of the cells medium and karyotype analysis of the mesenchymal stem cells. Only the safe cells were harvested and transplanted by multiple intramuscular injections into the impaired lower limbs. Follow-up index include: efficacy (pain,ulcer healing rate, lower limb amputation rate and ,ankle-brachial index,magnetic resonance angiography,electromyogram) and safety (infection of the injection site, fever, and tumour generation).

Inclusion Criteria:

• Diabetes mellitus Type 2
• Age 18 - 75 years
• Subject has an Ankle-brachial index < 0.9
• Subject has had previous conservative treatment which resulted in little or no improvement
• Subject has had no stem cell treatment within the past 6 months
• No sufficient response to best standard care delivered for six weeks.
• No surgical or radiological interventional option for revascularisation as confirmed by a vascular surgeon and an interventional radiologist
• Signed informed consent
• Absence of life-threatening complications from the ischemic limb
• Life expectancy more than 2 years
• Negative pregnancy test when applicable

Exclusion Criteria:

• Diabetic retinopathy
• History of neoplasm or hematological disease
• Uncontrolled high blood pressure (>180/110)
• Severe cardiac insufficiency (New York Heart Association [NYHA] IV) or ejection fraction<30%
• Malignant ventricular arrythmia
• Deep venous thrombosis during the last 3 months
• Active bacterial infection
• Body mass index > 35 Kg/m2
• Stroke or myocardial infarction during the last 3 months