인체 기관지 상피세포에서 Mycoplasma pneumoniae 항원이 IL-8 유전자 발현에 미치는 영향

Abstract

Purpose : Mycoplasma pneumoniae is a common cause of lower respiratory disease. Several studies have suggested that M. pneumoniae respiratory infection is associated with re-active airway disease and asthma. It has been suggested that Interleukin-8(IL-8) has a role in the pathogenesis of allergic inflammation of bronchial asthma and is well known to be expressed in bronchial epithelial cells. Methods : In this study, we examined the effect of M pneumoniae extract and the role of mitogen-activated protein kinases(MAPKs) on IL-8 expression in human lung epithelial cells. IL-8 levels were determined by an enzyme linked-immunosorbent assay. Extracellular signal-regulated kinase(ERK) phosphorylation was assessed by western blotting. Results : In A549 cells, AT. pneumoniae extract induced IL-8 release in a tame- or dose-dependent manner. Pretreatment with PD98059, which blocks the activation of MAPK/ERK kinase 1, before M. pneumoniae extract stimulation inhibited the increase in the production of IL-8 by 64.4% at 25 M. Stimulation of A549 cells by extract caused an increase in the activity of ERK, compared with the non-stimulated cells. The extract stimulation had no effect on the activities of p38. Conclusion : These observations suggest that activation of ERK by M. pneumoniae ex-tract may be one of the mechanisms that result in the increase of the production of IL-8.