title: Myofibroblastic Conversion and Regeneration of Mesothelial Cells in Peritoneal and Liver Fibrosis.
abstract: Mesothelial cells (MCs) form a single epithelial layer and line the surface of body cavities and internal organs. Patients who undergo peritoneal dialysis often develop peritoneal fibrosis that is characterized by the accumulation of myofibroblasts in connective tissue. Although MCs are believed to be the source of myofibroblasts, their contribution has remained obscure. We determined the contribution of peritoneal MCs to myofibroblasts in chlorhexidine gluconate (CG)-induced fibrosis compared with that of phenotypic changes of liver MCs. CG injections resulted in disappearance of MCs from the body wall and the accumulation of myofibroblasts in the connective tissue. Conditional linage tracing with Wilms tumor 1 (Wt1)-CreERT2 and Rosa26 reporter mice found that 17% of myofibroblasts were derived from MCs in peritoneal fibrosis. Conditional deletion of transforming growth factor-β type II receptor in Wt1(+) MCs substantially reduced peritoneal fibrosis. The CG treatment also induced myofibroblastic conversion of MCs in the liver. Lineage tracing with Mesp1-Cre mice revealed that Mesp1(+) mesoderm gave rise to liver MCs but not peritoneal MCs. During recovery from peritoneal fibrosis, peritoneal MCs, but not liver MCs, contribute to the regeneration of the peritoneal mesothelium, indicating an inherent difference between parietal and visceral MCs. In conclusion, MCs partially contribute to myofibroblasts in peritoneal and liver fibrosis, and protection of the MC layer leads to reduced development of fibrous tissue.
authors.affiliation: Department of Pathology, Southern California Research Center for Alcoholic Liver and Pancreatic Diseases (ALPD) and Cirrhosis, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Lua
authors.affiliation: Department of Pathology, Southern California Research Center for Alcoholic Liver and Pancreatic Diseases (ALPD) and Cirrhosis, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Yuchang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Division of Nephrology, Los Angeles County+University of Southern California Medical Center, Los Angeles, California.
authors.forename: Lamioko S
authors.initials: LS
authors.lastname: Pappoe
authors.affiliation: Department of Pathology, Southern California Research Center for Alcoholic Liver and Pancreatic Diseases (ALPD) and Cirrhosis, Keck School of Medicine, University of Southern California, Los Angeles, California. Electronic address: asahina@usc.edu.
authors.forename: Kinji
authors.initials: K
authors.lastname: Asahina
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D002710:Chlorhexidine / Q000031:analogs & derivatives; D015536:Down-Regulation / Q000187:drug effects; D004847:Epithelial Cells / Q000473:pathology / Q000502:physiology; D017353:Gene Deletion; D005786:Gene Expression Regulation / Q000187:drug effects; D008103:Liver Cirrhosis / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology*; D008822:Mice, Transgenic; D058628:Myofibroblasts / Q000473:pathology* / Q000502:physiology; D010529:Peritoneal Cavity / Q000166:cytology; D056627:Peritoneal Fibrosis / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology*; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis / Q000235:genetics; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics; D012038:Regeneration / Q000502:physiology; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology
chemical_list: D018125:Receptors, Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II; C010882:chlorhexidine gluconate; D002710:Chlorhexidine