CONCLUSION

Pathogenic N. fowleri, a brain-eating amoeba associated with swimming and other recreational water activities, results in intense inflammatory reactions in the forebrain tissue:a condition known as acute PAM. To investigate what kinds of inflammasome-related molecules are expressed in target cells due to N. fowleriinfection,human macrophage THP-1 cells were co-cultured with N. fowleritrophozoites under the non-contact system using a transwell, and consequently IL-1β production was estimated.

In THP-1 cells co-cultured with N. fowleritrophozoites in a non-contact system, the activation of caspase-1 and production of IL-1β were evaluated by Western blot and ELISA analysis. Also, the formation of NLRP3/ASC inflammasome complex in THP-1 cells induced the caspase-1 activation and consequent IL-1β secretion. In addition, both, the activation of caspase-1 andthe production of IL-1β from THP-1 cells,wereinhibited by pretreatment of THP-1 cells with inhibitors, such as KCl, CA-074, Glybenclamide, Z-VAD-FMK, and Bay 11-7082.

In conclusion, this study suggests that N. fowleriinfection induces caspase-1 activation through the NLRP3-inflammasome formation,withsubsequent IL-1β secretion, which consequently causes the inflammation.

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３５ cytochalasin D (phagocytosis inhibitor), Z-VAD-FMK (caspase-1 inhibitor), KCl (K⁺ channel inhibitor), Glybenclamide (ATP-dependent K⁺ channel inhibitor), CA-074 (cathepsin B inhibitor), Bay 11-7082 (NF-κB inhibitor) 를 표적세포에 전처리하여파울러자유아메바와 함께 비접촉적으로 배양하였다. 억제