Lipopolysaccharide- and ß-glucan-stimulated macrophages upregulate cytolosic phospholipase A2 IVC in nasal epithelial cells: role of TNF-α
(English)Manuscript (preprint) (Other academic)
Phospholipase A2 (PLA2) is a superfamily of enzymes that may play a major role in airways inflammation. We investigated the gene expression of 20 different PLA2 types in nasal epithelial cells (RPMI 2650) before and after incubation with cell growth medium from human monocyte-derived macrophages exposed to lipopolysaccharide (LPS) or ß-1,3-D-glucan (ßG). The macropbages were exposed to LPS (10 µ/ml) or ßG (500 µg/ml) for 48 hours and the mRNA levels of the different PLA2 types in RPMI 2650 cells were determined after incubation for 18 hours using reverse transcriptase-PCR (RT-PCR). It appeared that the mRNA levels of PLA2 type IVC were significantly increased after incubation, both with medium from LPS-exposed and ßG-exposed macrophages. In both cases, the increased PLA2 IVA mRNA expression was abolished by TNF-α antibodies and by the NF-κB inhibitor, pyrrolidine dithiocarbamate (PDTC). There were no significant alterations in the mRNA levels of the other PLA2 types, including PLA2 IVA. These findings indicate that both LPS- and ßG-activated macrophages can induce the gene expression of PLA2 IVC in nasal epithelial cells, and that this upregulation is mediated through TNF-α and under NF-κB control. Further studies are required to clarify whether these mechanisms may operate to cause inflammation in the nasal mucosa in vivo.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-84953OAI: oai:DiVA.org:liu-84953DiVA: diva2:563152