Table 1.
Potential criteria for potency assay for MSC based on secretion of paracrine factors alone.
| Soluble factors* | Important in |
|---|---|
| Keratinocyte growth factor | Apoptosis |
| Hepatocyte growth factor | Surfactant synthesis |
| Epidermal growth factor | Alveolar fluid transport Endothelial permeability? |
| Angiopoietin-1 | Epithelial & endothelial permeability? |
| IL-1 receptor antagonist (IL-1RA) | Anti-inflammatory |
| IL-10 | |
| Prostaglandin E2 |
A correlation between the level of cytokines, growth and anti-permeability factors secreted will need to be made with its therapeutic efficacy in animal and human models of ALI/ARDS. For example, will MSC improve alveolar fluid clearance, lung water or lung endothelial permeability to protein or reduce the inflammatory milieu within the injured alveolus.
*
Secretion of some soluble factors may be dependent on cell-cell contact or the alveolar milieu itself, such as IL-10 or prostaglandin E2.