Araya Dharmkrong at ChusattayanondSiriphan BoonsilpJitra KasisitAtsadang BoonmeeSaradee WaritMahidol UniversityThailand National Center for Genetic Engineering and Biotechnology2018-09-242018-09-242010-12-01Parasitology International. Vol.59, No.4 (2010), 512-516138357692-s2.0-77958478281https://repository.li.mahidol.ac.th/handle/20.500.14594/29165A Thai Acanthamoeba isolate named AS recovered from a corneal scraping of a keratitis patient was genotypically determined as T4. AS trophozoites were used for studying Acanthamoeba-induced apoptosis in mouse neuroblastoma NA cells during in vitro co-cultivation. The Acanthamoeba-exposed NA cells showed signs of apoptosis including cell shrinkage, nuclear condensation and DNA fragmentation. The effect was confirmed by DNA laddering electrophoresis. Involvement of caspase enzymes and mitochondrial pro- and anti-apoptotic proteins (Bax and Bcl-2) in AS-induced apoptosis was determined. The use of Z-VAD-FMK, a pan-caspase inhibitor, significantly reduced the apoptotic effect, while Bax/Bcl-2 ratio analysis showed a significant increase in the expression of apoptotic proteins in AS-exposed NA cells. These results strongly indicated that apoptosis induced by AS trophozoites is caspase-dependent and is mediated by over-expression of pro-apoptotic proteins in the mitochondrial pathway. This is the first report on the role of Bax in mediating apoptosis induced by Acanthamoeba. © 2010 Elsevier Ireland Ltd.Mahidol UniversityImmunology and MicrobiologyMedicineArticleSCOPUS10.1016/j.parint.2010.06.007