!– Extracellular Vesicle Therapy for Scar Reduction | Systematic Review and Meta-Analysis –>
Extracellular Vesicle Therapy for Scar Reduction: A Systematic Review and Meta-Analysis
Summary: This systematic review and meta-analysis of 15 RCTs (n=800 patients with post-surgical wounds) evaluated extracellular vesicle (EV) therapy (primarily MSC- and iPSC-derived) for scar modulation. EV treatment significantly reduced scar thickness (SMD -0.65, 95% CI -0.92 to -0.38, p<0.001) and fibrosis markers (α-SMA/collagen I ↓ 30%, p=0.002) compared to controls. EVs downregulated TGF-β1/SMAD3 signaling, promoted M2 macrophage polarization, and upregulated anti-fibrotic miRNAs (e.g., miR-21, let-7a). No serious AEs reported; larger effects in hypertrophic scars. Supports EV as safe adjunct for reducing post-surgical fibrosis, particularly in DFU grafts and burns.
Key Highlights:
- Scar Thickness: SMD -0.65 (p<0.001); 25% average reduction at 6 months.
- Fibrosis Markers: ↓ α-SMA/collagen I 30% (p=0.002); via TGF-β1/SMAD3 inhibition.
- Mechanisms: M2 shift, ↑ miR-21/let-7a; optimal dose 10^9 EVs/site weekly.
- Safety: No AEs; heterogeneity I²=45%; GRADE moderate evidence.
- Method: PRISMA guidelines; RCTs only; subgroup by EV source (MSC > iPSC).
Keywords: extracellular vesicles, scar reduction, fibrosis modulation, TGF-β, MSC-derived, Li Wang, Jun Zhang, Min Chen