Umbilical cord blood mononuclear cells (MNC) may improve the wound repair ability. This study aims to investigate the role of MNC in refractory diabetic foot ulcer by comparing the combination of PRP and MNC with PRP alone.

The difficulty in the healing of diabetic foot is related to the loss of local repair microenvironment. The platelet rich plasma (PRP) can improve the repair ability, however, the requirement for wound bed preparation is strict, or treatment failure may occur. Umbilical cord blood mononuclear cells (MNC) may provide a better repair environment through paracrine action. This study aims to investigate the role of MNC in refractory diabetic foot ulcer by comparing the combination of PRP and MNC with PRP alone.

Inclusion Criteria:

1. The age of the patients is 18-80 years old;
2. Diabetic foot is diagnosed and Wagner grade is above Ⅱ;
3. The duration of ulcer is 2 months or more, with no healing trend for 2 weeks or more.
4. Fasting blood glucose ≤ 9mmol / L, 2 hours postprandial blood glucose ≤ 13mmol / L;
5. The skin oxygen partial pressure around the wound is more than 20mmHg;
6. Sign written informed consent.

Exclusion Criteria:

1. Acute spreading infection of the wound, e.g. massive exudation, redness, swelling, heat, pain.
2. Acute myocardial infarction, heart failure, hepatitis;
3. Active bleeding or hematoma in the wound;
4. Serum albumin <25g/L;
5. Hemoglobin <80g/L;
6. Platelets <50×109/L;
7. Poor cooperate or compliance;The patient cannot cooperate or is.
8. Mentally disabled.

all IPD that underlie results in a publication

starting 6 months after publication, for 1 year

The IPD and supporting information will be shared by contact PI (Long Zhang)'s Email, upon the request of the scientific journal editor.