Transition of mesothelial cell to fibroblast in peritoneal dialysis: EMT, stem cell or bystander?

Area of Science:

• Nephrology
• Cell Biology
• Histology

Background:

• Long-term peritoneal dialysis (PD) is associated with peritoneal fibrosis, characterized by mesothelial cell (MC) loss and submesothelial thickening.
• The origin of myofibroblasts, key contributors to fibrosis, remains a critical question in peritoneal fibrosis research.

Purpose of the Study:

• To review the evidence for and against epithelial-mesenchymal transition (EMT) as the primary mechanism driving myofibroblast generation in PD-related peritoneal fibrosis.
• To discuss alternative sources of myofibroblasts, particularly the potential role of peritoneal mesothelial cells (MCs).

Main Methods:

• Literature review of clinical and experimental studies on peritoneal fibrosis and EMT.
• Analysis of recent findings from cell isolation and lineage-tracing experiments.

Main Results:

• While EMT has been a proposed mechanism for myofibroblast generation, recent studies cast doubt on its significance in organ fibrogenesis.
• Evidence suggests the existence of peritoneal progenitor cells capable of differentiating into myofibroblasts.

Conclusions:

• The role of EMT in peritoneal fibrosis requires re-evaluation.
• Peritoneal mesothelial cells (MCs) possess plasticity and may contribute to myofibroblast pools, warranting further investigation into their role in peritoneal fibrogenesis.