Theory 04/Regenerative Biology/Regeneration
Regeneration Is a Ratio
Why some tissues regenerate and others scar is usually explained by progenitors. The other term may be the deciding one.
Regenerative capacity is set by the ratio of progenitor pool to inflammatory load rather than by the size of the progenitor pool, so a tissue with many progenitors can fail to regenerate if inflammation consumes them.
01The evidence
Regeneration is age-dependent and inflammation-dependent in organisms that retain progenitors, and blocking inflammation restores regeneration in otherwise refractory states.
02The tension
Models emphasise progenitor abundance and developmental competence. They predict regeneration where progenitors exist, which fails in adults and in inflamed tissue.
03The mechanism
Progenitors must survive and proliferate to rebuild tissue. Inflammation recruits cells that consume them and signals that bias differentiation toward repair rather than replacement.
That makes the ratio the determinant, and predicts that reducing inflammation should restore regeneration without adding progenitors, while adding progenitors should fail in an inflamed bed.
04What this is not
Those count stem cells. This counts them relative to the injury environment, which explains failure despite abundance.
05Predictions
- P1Regeneration should track the ratio.
- P2Anti-inflammatory treatment should restore it at constant progenitors.
- P3Progenitor transplantation should fail in inflamed beds.
06Refutation
Regeneration tracking progenitor number at controlled inflammation would remove the ratio.
07What it changes
It would make inflammation control a regenerative therapy.