Induction of IL-8 by Chlamydia trachomatis through MAPK pathway rather than NF-_κB pathway

Objective: To determine the signaling pathway required for Chlamydial induction of IL-8 expression in epithelial cells. Methods: The production and localization of IL-8 in Chlamydiainfected Hela 229 cells were monitored using Western blot, immunoflourescence, and ELISA. Activation of MAPK and NF- _κB signaling pathways were detected by Western blot and immunoflourescence. The effect of different signaling pathways on Chlamydia-induced Il-8 was measured by experiments of chemical inhibitors. Results: IL-8 was induced by Chlamydia and was time-dependant. Chlamydial infection activated MAPK/ERK and MAPK/p38 pathways but not NF- _κkB pathway. Chlamydial induction of IL-8 was blocked by small molecule inhibitors targeting the ERK and p38 pathways. Conclusion: Chlamydia-induced IL-8 in cervical epithelial cells, the natural target cell type of Chlamydia trachomatis infection, is dependent on MAPK pathway but not NF-_κB pathway, which provides important information for further understanding the molecular mechanism of Chlamydia-induced inflammatory pathologies.