- 作者: Chien-Ying Liu Yun-Hen Liu Shu-Min Lin Chih-Ten Yu Chun-Hua Wang Horng-Chyuan Lin Chien-Chyuan Lin Chien-Huang Lin Han-Pin Kuo
- 作者服務機構: Department of Thoracic Medicine II and Thoracic Surgery, Chang-Gung Memorial Hospital, Department of Medical Technology, Taipei Medical University, Taipei, Taiwan, ROC
- 中文摘要: --
- 英文摘要: Clearance of apoptotic neutrophils by alveolar macro-phages plays an important role in the resolution phase oflung inflammation.If not cleared, apoptotic neutrophilsare postulated to release histotoxic granular contents.Since numerous cellular proteins are degraded duringapoptosis, we sought to determine whether functionalserine proteinases are indeed released by apoptosingneutrophils in vitro.In a coculture system,cytokine-acti-vated neutrophils induced detachment in the human epi-thelial cell line, A549.This process was CD18- and serineproteinase-dependent. Early apoptotic neutrophils in-duced significant detachment, but live, senescent, rest-ing neutrophils and terminal,secondary necrotic neutro-phils had a different effect. This detachment process wasCD18-independent but serine proteinase-dependent.Similarly, detachment occurred with primary humansmall airway epithelial cells. Notably, epithelial cell de-tachment correlated with the transition of early apoptoticneutrophils to secondary necrosis and with the accumu-lation of elastase in the supernatant. The membraneintegrity of lung epithelial cells was damaged in advanceof significant cell detachment. These observations sug-gest that not only live activated neutrophils but alsoapoptosing neutrophils can reveal functional elastaseactivities. Furthermore, the rapidity of the transition em-phasizes the importance of the prompt clearance ofapoptotic neutrophils before they progress to secondarynecrosis at the site of lung inflammation.
- 中文關鍵字: --
- 英文關鍵字: Apoptosis. Neutrophil. Protease. Phagocytosis. Lung injury