Role of the Nfa1 protein in pathogenic Naegleria fowleri cocultured with CHO target cells.
Naegleria fowleri, a free-living amoeba, exists as a virulent pathogen which causes fatal primary amoebic meningoencephalitis in experimental animals and humans. Using infected and immune mouse sera, we previously cloned an nfa1 gene from a cDNA library of N. fowleri by immunoscreening. The nfa1 gene (360 bp) produced a recombinant 13.1-kDa protein, and the Nfa1 protein showed pseudopodium-specific immunolocalization on a trophozoite of N. fowleri. In this study, the role of the Nfa1 protein as a cell contact mechanism of N. fowleri cocultured with target cells was observed by an immunofluorescence assay with an anti-Nfa1 polyclonal antibody. Using confocal microscopic findings, the Nfa1 protein was located on the pseudopodia of N. fowleri trophozoites. The Nfa1 protein in N. fowleri trophozoites cocultured with CHO target cells was also located on pseudopodia, as well as in a food cup formed as a phagocytic structure in close contact with target cells. The amount of nfa1 mRNA of N. fowleri was strongly increased 6 h after coculture.
Department of Microbiology, Ajou University School of Medicine, Suwon 442-749, Korea.
Su-Yeon
SY
Kang
Kyoung-Ju
KJ
Song
Seok-Ryoul
SR
Jeong
Jong-Hyun
JH
Kim
Sun
S
Park
Kyongmin
K
Kim
Myung-Hee
MH
Kwon
Ho-Joon
HJ
Shin
D000818:Animals; D000913:Antibodies, Protozoan / Q000494:pharmacology; D000953:Antigens, Protozoan / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D016466:CHO Cells; D006224:Cricetinae; D004660:Encephalitis / Q000276:immunology / Q000469:parasitology; D051379:Mice; D016848:Naegleria fowleri / Q000166:cytology / Q000254:growth & development* / Q000472:pathogenicity; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*; D015800:Protozoan Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D011554:Pseudopodia / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C460560:Nfa1 protein, Naegleria fowleri; D015800:Protozoan Proteins; D012333:RNA, Messenger