RT Journal Article T1 Peritoneal repairing cells: a type of bone marrow derived progenitor cells involved in mesothelial regeneration A1 Carmona-Mejías, Rita María A1 Cano, E A1 Grueso, E A1 Ruiz-Villalba, A A1 Bera, TK A1 Gaztambide, J A1 Segovia, JC A1 Muñoz-Chápuli, R K1 Peritoneo - Enfermedades AB The peritoneal mesothelium exhibits a high regenerative ability. Peritoneal regeneration is concomitant with the appearance, in the coelomic cavity, of a free-floating population of cells whose origin and functions are still under discussion. We have isolated and characterized this cell population and we have studied the process of mesothelial regeneration through flow cytometry and confocal microscopy in a murine model lethally irradiated and reconstituted with GFP-expressing bone marrow cells. In unoperated control mice, most free cells positive for mesothelin, a mesothelial marker, are green fluorescent protein (GFP). However, 24 hrs after peritoneal damage, free mesothelin+/ GFP+ cells appear in peritoneal lavages. Cultured lavage peritoneal cells show colocalization of GFP with mesothelial (mesothelin, cytokeratin) and fibroblastic markers. Immunohistochemical staining of the peritoneal wall also revealed colocalization of GFP with mesothelial markers and with procollagen-1 and smooth muscle α-actin. This was observed in the injured area as well as in the surrounding not-injured peritoneal surfaces. These cells, which we herein call peritoneal repairing cells (PRC), are very abundant 1 week after surgery covering both the damaged peritoneal wall and the surrounding uninjured area. However, they become very scarce 1 month later, when the mesothelium has completely healed. We suggest that PRC constitute a type of monocyte-derived cells, closely related with the tissue-repairing cells known as ‘fibrocytes’ and specifically involved in peritoneal reparation. Thus, our results constitute a synthesis of the different scenarios hitherto proposed about peritoneal regeneration, particularly recruitment of circulating progenitor cells and adhesion of free-floating coelomic cells. PB Wiley Online Library YR 2011 FD 2011-05 LK https://hdl.handle.net/10630/34011 UL https://hdl.handle.net/10630/34011 LA eng NO Carmona, R., Cano, E., Grueso, E., Ruiz-Villalba, A., Bera, T.K., Gaztambide, J., Segovia, J.C. and Muñoz-Chápuli, R. (2011), Peritoneal repairing cells: a type of bone marrow derived progenitor cells involved in mesothelial regeneration. Journal of Cellular and Molecular Medicine, 15: 1200-1209. https://doi.org/10.1111/j.1582-4934.2010.01087.x NO This work was supported by grants BFU2008–02384 and SAF2008–1883, (Ministerio de Ciencia e Innovación), RD06/0010/0015 (TerCel network, ISCIII), P06-CTS-01614, P08-CTS-03618 (Junta de AndalucÌa) and LSHM-CT-2005–018630 (VI framework, UE). DS RIUMA. Repositorio Institucional de la Universidad de Málaga RD 20 ene 2026