Expression of secretory phospholipase A2 enzymes in lungs of humans with pneumonia and their potential prostaglandin-synthetic function in human lung-derived cells
- 22 March 2005
- journal article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 387 (1), 27-38
- https://doi.org/10.1042/bj20041307
Abstract
Although a number of sPLA2 (secretory phospholipase A2) enzymes have been identified in mammals, the localization and functions of individual enzymes in human pathologic tissues still remain obscure. In the present study, we have examined the expression and function of sPLA2s in human lung-derived cells and in human lungs with pneumonia. Group IID, V and X sPLA2s were expressed in cultured human bronchial epithelial cells (BEAS-2B) and normal human pulmonary fibroblasts with distinct requirement for cytokines (interleukin-1β, tumour necrosis factor α and interferon-γ). Lentivirus- or adenovirus-mediated transfection of various sPLA2s into BEAS-2B or normal human pulmonary fibroblast cells revealed that group V and X sPLA2s increased arachidonate release and prostaglandin production in both cell types, whereas group IIA and IID sPLA2s failed to do so. Immunohistochemistry of human lungs with pneumonia demonstrated that group V and X sPLA2s were widely expressed in the airway epithelium, interstitium and alveolar macrophages, in which group IID sPLA2 was also positive, whereas group IIA sPLA2 was restricted to the pulmonary arterial smooth muscle layers and bronchial chondrocytes, and group IIE and IIF sPLA2s were minimally detected. These results suggest that group V and X sPLA2s affect lung pathogenesis by facilitating arachidonate metabolism or possibly through other functions.Keywords
This publication has 53 references indexed in Scilit:
- Localization of various secretory phospholipase A2 enzymes in male reproductive organsBiochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids, 2004
- Human Group V Phospholipase A2 Induces Group IVA Phospholipase A2-independent Cysteinyl Leukotriene Synthesis in Human EosinophilsJournal of Biological Chemistry, 2003
- Novel Mammalian Group XII Secreted Phospholipase A2Lacking Enzymatic Activity,Biochemistry, 2003
- Perinuclear localization of cytosolic phospholipase A2α is important but not obligatory for coupling with cyclooxygenasesFEBS Letters, 2003
- Susceptibility of Cyclooxygenase-2-Deficient Mice to Pulmonary FibrogenesisThe American Journal of Pathology, 2002
- Phospholipase A2 enzymesProstaglandins & Other Lipid Mediators, 2002
- Cellular Arachidonate-releasing Function and Inflammation-associated Expression of Group IIF Secretory Phospholipase A2Journal of Biological Chemistry, 2002
- Ultrastructural Localization of Secretory Type II Phospholipase A 2 in Atherosclerotic and Nonatherosclerotic Regions of Human ArteriesArteriosclerosis, Thrombosis, and Vascular Biology, 1998
- Cytokine-stimulated secretion of group II phospholipase A2 by rat mesangial cells. Its contribution to arachidonic acid release and prostaglandin synthesis by cultured rat glomerular cells.JCI Insight, 1993
- Phospholipase A2 — a mediator between proximal and distal effectors of inflammationImmunology Today, 1991