Contact-Independent Cell Death of Human Microglial Cells due to Pathogenic Naegleria fowleri Trophozoites.
10.3347/kjp.2008.46.4.217
- Author:
Jong Hyun KIM
1
;
Daesik KIM
;
Ho Joon SHIN
Author Information
1. Department of Microbiology, and Department of Molecular Science & Technology, Ajou University School of Medicine, Suwon 443-721, Korea. kdaesik@dongnam.ac.kr
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
Naegleria fowleri;
cell death;
cytotoxicity;
microglial cells
- MeSH:
Animals;
Apoptosis;
Cell Line;
Humans;
Microglia/*cytology/*parasitology;
Naegleria fowleri/*physiology;
Phagocytosis/physiology
- From:The Korean Journal of Parasitology
2008;46(4):217-221
- CountryRepublic of Korea
- Language:English
-
Abstract:
Free-living Naegleria fowleri leads to a fatal infection known as primary amebic meningoencephalitis in humans. Previously, the target cell death could be induced by phagocytic activity of N. fowleri as a contact-dependent mechanism. However, in this study we investigated the target cell death under a non-contact system using a tissue-culture insert. The human microglial cells, U87MG cells, co-cultured with N. fowleri trophozoites for 30 min in a non-contact system showed morphological changes such as the cell membrane destruction and a reduction in the number. By fluorescence-activated cell sorter (FACS) analysis, U87MG cells co-cultured with N. fowleri trophozoites in a non-contact system showed a significant increasse of apoptotic cells (16%) in comparison with that of the control or N. fowleri lysate. When U87MG cells were co-cultured with N. fowleri trophozoites in a non-contact system for 30 min, 2 hr, and 4 hr, the cytotoxicity of amebae against target cells was 40.5, 44.2, and 45.6%, respectively. By contrast, the cytotoxicity of non-pathogenic N. gruberi trophozoites was 10.2, 12.4, and 13.2%, respectively. These results suggest that the molecules released from N. fowleri in a contact-independent manner as well as phagocytosis in a contact-dependent manner may induce the host cell death.
