Effect of Hematopoietic Stem Cells in Chronic Wounds Using a Pressure Sore Model: A Pilot Study on Feasibility, Safety and Potential Effects

Aim of the study:

Evaluation of feasibility, safety and potential effects of stem cells on chronic wounds using a pressure sore model.

Clinical relevance:

• Accelerated healing of uncomplicated wounds
• Enhanced healing of complicated (chronic, non-healing) wounds

Study design:

• Prospective controlled phase I/II study
• Cohort of 5 patients in pilot study, then reevaluation

Patients:

- Para- and tetraplegic patients with sacral pressure sores grade III-IVA according to the classification of Daniel and Seiler

Methods:

1. First surgical intervention:

• Radical debridement of pressure sore
• Bone marrow harvest from the iliac crest
• Isolation of hematopoietic stem cells, aiming to gain > 1 mio. CD 34+ cells per patient under GMP conditions

3. Stem cell therapy (after 2 days)

• Injection of stem cells in suspension (50'000 CD 34+ cells in 100 microliter saline per cm2 of wound surface) on one half of the total wound surface and cell-free saline on the other half as a control

4. Second surgical intervention (after 3-4 weeks):

• Complete excision of the wound
• Closure of the defect by fasciocutaneous flap

5. Evaluation of wound healing:

• Clinical
• 3D laser imaging
• Histology
• Growth factor assay