Hiroki Ebana1,2,3, Takuo Hayashi4,5, Keiko Mitani4,5, Etsuko Kobayashi6,5, Toshio Kumasaka7,5, Teruaki Mizobuchi8,5, Masatoshi Kurihara8,5, Fumiyuki Takahashi6, Kazuhisa Takahashi6, Kuniaki Seyama6,5. 1. Division of Respiratory Medicine, Faculty of Medicine, Graduate School of Medicine, Juntendo University, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. h-ebana@juntendo.ac.jp. 2. Division of Thoracic Surgery, Pneumothorax Research Center, Nissan Tamagawa Hospital, Tokyo, Japan. h-ebana@juntendo.ac.jp. 3. The Study Group for Pneumothorax and Cystic Lung Diseases, Tokyo, Japan. h-ebana@juntendo.ac.jp. 4. Division of Human Pathology, Faculty of Medicine, Graduate School of Medicine, Juntendo University, Tokyo, Japan. 5. The Study Group for Pneumothorax and Cystic Lung Diseases, Tokyo, Japan. 6. Division of Respiratory Medicine, Faculty of Medicine, Graduate School of Medicine, Juntendo University, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. 7. Department of Pathology, Japanese Red Cross Medical Centre, Tokyo, Japan. 8. Division of Thoracic Surgery, Pneumothorax Research Center, Nissan Tamagawa Hospital, Tokyo, Japan.
Abstract
PURPOSE: The pleural covering technique, i.e., wrapping a part of or the entire surface of the lung with oxidized regenerative cellulose (ORC), reinforces visceral pleura through pleural thickening for patients with pneumothorax and cystic lung diseases. However, it remains undetermined how ORC induces pleural thickening. METHODS: A histopathological examination was performed for lung specimens from patients who had recurrent pneumothoraces after pleural covering and re-operation (n = 5). To evaluate the influence of ORC on the pleura in vitro, we used MeT-5A cells (a human pleural mesothelial cell line). RESULTS: Pleural thickening was confirmed in all lung specimens examined. Three months after covering, the thickened pleura showed inflammatory cell infiltration, proliferation of myofibroblasts, and expression of fibronectin and TGF-β. However, after 1 year, those findings virtually disappeared, and the thickened pleura was composed mainly of abundant collagen. When MeT-5A cells were cultured in ORC-immersed medium, their morphology changed from a cobblestone to spindle-shaped appearance. The expression of E-cadherin decreased, whereas that of N-cadherin, α-smooth muscle actin, and fibronectin increased, suggesting mesothelial-mesenchymal transition (Meso-MT). CONCLUSIONS: Our results suggest that Meso-MT may be involved as a mechanism of pleural thickening induced by pleural covering with ORC.
PURPOSE: The pleural covering technique, i.e., wrapping a part of or the entire surface of the lung with oxidized regenerative cellulose (ORC), reinforces visceral pleura through pleural thickening for patients with pneumothorax and cystic lung diseases. However, it remains undetermined how ORC induces pleural thickening. METHODS: A histopathological examination was performed for lung specimens from patients who had recurrent pneumothoraces after pleural covering and re-operation (n = 5). To evaluate the influence of ORC on the pleura in vitro, we used MeT-5A cells (a humanpleural mesothelial cell line). RESULTS:Pleural thickening was confirmed in all lung specimens examined. Three months after covering, the thickened pleura showed inflammatory cell infiltration, proliferation of myofibroblasts, and expression of fibronectin and TGF-β. However, after 1 year, those findings virtually disappeared, and the thickened pleura was composed mainly of abundant collagen. When MeT-5A cells were cultured in ORC-immersed medium, their morphology changed from a cobblestone to spindle-shaped appearance. The expression of E-cadherin decreased, whereas that of N-cadherin, α-smooth muscle actin, and fibronectin increased, suggesting mesothelial-mesenchymal transition (Meso-MT). CONCLUSIONS: Our results suggest that Meso-MT may be involved as a mechanism of pleural thickening induced by pleural covering with ORC.
Authors: Richard P G Ten Broek; Martijn W J Stommel; Chema Strik; Cornelis J H M van Laarhoven; Frederik Keus; Harry van Goor Journal: Lancet Date: 2013-09-27 Impact factor: 79.321