The nfa1 Gene Contributed on the Contact-dependent Pathogenic Mechanisms of Naegleria fowleri.
10.7599/hmr.2010.30.3.204
- Author:
Ho Joon SHIN
1
Author Information
1. Department of Microbiology, and Department of Molecular Science and Technology, Ajou University School of Medicine, Suwon, Korea. hjshin@ajou.ac.kr
- Publication Type:In Vitro ; Review
- Keywords:
Naegleria fowleri;
nfa1 gene;
Cytotoxicity;
Protective immunity;
Recombinant protein
- MeSH:
Amoeba;
Animals;
Child;
Clone Cells;
Coculture Techniques;
Gene Library;
Humans;
Immunization;
Immunohistochemistry;
Meningoencephalitis;
Mice;
Naegleria;
Naegleria fowleri;
Nucleotides;
Rats;
RNA, Messenger;
RNA, Small Interfering;
Survival Rate;
Trophozoites;
Young Adult
- From:Hanyang Medical Reviews
2010;30(3):204-212
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Free-living Naegleria fowleri is a causal agent of primary amoebic meningoencephalitis in mainly children and young adults. An nfa1 gene, encoding 360 bp of nucleotides, was cloned from a N. fowleri cDNA library by SEREX method. By immunohistochemistry and a confocal microscope, Nfa1 protein was found in amoebic pseudopods, especially in food-cups, when amoeba was in contact with target cells. When an anti-Nfa1 antibody was added to the coculture system, the cytotoxicity of N. fowleri trophozoites onto target cells was decreased, and the severe morphological destruction of rat microglial cells cocultured with N. fowleri trophozoites was reduced. In a tansfection system, an expression vector with an nfa1 gene was successful transfected into nonpathogenic N. gruberi, and transgenic N. gruberi showed the increasing in vitro cytotoxicity. The siRNA decreased the expression levels of nfa1 mRNA and Nfa1 protein in transfected N. fowleri trophozoites. On the immunization of mice with the rNfa1 protein, the protective immunity of host was induced. Thus, mice showed the prolonged mean survival times in PAM-developed mice. In final, the nfa1 gene and Nfa1 protein play an important role in the pathogenesis of N. fowleri infection.
