What is the efficacy of stem cell (Stem Cell) replacement in wound care?

Stem Cell Replacement in Wound Care: Limited Evidence for Clinical Benefit

Based on current evidence, stem cell therapy is not recommended as a routine adjunct therapy for wound healing due to insufficient high-quality evidence supporting its efficacy and cost-effectiveness.

Current Evidence and Recommendations

The most recent guidelines from the International Working Group on Diabetic Foot (IWGDF) specifically address various cell therapies for wound healing:

• The IWGDF suggests not using other cell therapy (including adipocytes, fibroblasts, keratinocytes, bone marrow-derived stem cells, and mesenchymal stromal cells) as an adjunct therapy to standard of care for wound healing in diabetic foot ulcers (Conditional recommendation; Low quality evidence) 1

• Studies investigating stem cell therapies show heterogeneity of outcomes with some showing no improvement in healing, and those reporting positive benefits being at high risk of bias 1

• The single study of periwound autologous bone marrow stem cells in patients with critical limb ischemia had high loss to follow-up with only per-protocol analysis presented 1

Types of Stem Cell Therapies Evaluated

Several types of stem cell therapies have been studied for wound healing:

1. Autologous adipocyte-derived stem cells

   • Limited evidence with only two outcome-blinded studies 1
   • One high-quality but small RCT showed autologous adipose tissue grafting was effective for digital ulcer healing in systemic sclerosis patients 1

2. Bone marrow-derived stem cells

   • Studies had significant methodological limitations 1
   • One study designed to stimulate the release of bone marrow stem cells was not powered to show a difference in healing 1

3. Mesenchymal stromal cells

   • A study of allogeneic bone marrow mesenchymal stromal cells was at high risk of bias 1
   • Results from trials on mesenchymal stromal cells for digital ulcers are still awaited 1

Practical Considerations

Resource Implications and Feasibility

• Stem cell therapies require significant resources:
  • Access to cell culture facilities
  • Specialized expertise for cell harvesting and processing
  • Regular patient follow-up
  • These requirements decrease equity and feasibility, particularly in healthcare systems in low-income countries 1

Cost-Effectiveness

• Most studies lack formal health economic analyses 1
• The high resource use involved in these interventions suggests moderate to high costs 1
• Cost-effectiveness does not currently favor stem cell therapies over standard of care

Current Status in Clinical Practice

The American Diabetes Association's Standards of Care categorizes stem cell therapies as one of nine broad categories of advanced wound therapies, but notes that they should only be considered when wounds fail to show a reduction of 50% or more after 4 weeks of appropriate standard wound management 1

Research Limitations

Despite promising preclinical data showing that:

• Mesenchymal stromal cells may accelerate wound healing by modulating immune response and promoting angiogenesis 2
• BM-MSCs promote wound healing through differentiation and release of proangiogenic factors 3

Clinical translation remains limited by:

• High risk of bias in existing studies
• Lack of standardization in protocols
• Small sample sizes
• Inadequate blinding
• High dropout rates
• Lack of long-term follow-up data

Conclusion

While stem cell therapy shows theoretical promise for wound healing based on preclinical studies, current clinical evidence does not support its routine use. The balance of effects may favor the intervention in some cases, but this is based on limited studies with high risk of bias.

Standard wound care principles (offloading, debridement, revascularization, infection management, and appropriate dressings) remain the foundation of treatment, with advanced therapies considered only when standard approaches fail to produce adequate healing.