Figure 1. Proposed mechanisms for the predilection of fibrosis with aging.
Aging may result in “immunosenescence” that results in impaired antigen clearance and autoimmunity; additionally, senescence of epithelial cells and fibroblasts result in impaired regeneration and aberrant recapitulation of developmental genes. These processes may perpetuate epithelial injury/apoptosis and fibroblast activation that results in failed re-epithelialization, fibroblast persistence and progressive fibrosis.