Decreasing effect of an anti-Nfa1 polyclonal antibody on the in vitro cytotoxicity of pathogenic Naegleria fowleri.
The nfa1 gene was cloned from a cDNA library of pathogenic Naegleria fowleri by immunoscreening; it consisted of 360 bp and produced a 13.1 kDa recombinant protein (rNfa1) that showed the pseudopodia-specific localization by immunocytochemistry in the previous study. Based on the idea that the pseudopodia-specific Nfa1 protein mentioned above seems to be involved in the pathogenicity of N. fowleri, we observed the effect of an anti-Nfa1 antibody on the proliferation of N. fowleri trophozoites and the cytotoxicity of N. fowleri trophozoites on the target cells. The proliferation of N. fowleri trophozoites was inhibited after being treated with an anti-Nfa1 polyclonal antibody in a dose-dependent manner for 48 hrs. By a light microscope, CHO cells co-cultured with N. fowleri trophozoites (group I) for 48 hrs showed severe morphological destruction. On the contrary, CHO cells co-cultured with N. fowleri trophozoites and anti-Nfa1 polyclonal antibody (1:100 dilution) (group II) showed less destruction. In the LDH release assay results, group I showed 50.6% cytotoxicity, and group II showed 39.3%. Consequently, addition of an anti-Nfa1 polyclonal antibody produced a decreasing effect of in vitro cytotoxicity of N. fowleri in a dose-dependent manner.
Jeong
Seok-Ryoul
SR
Department of Microbiology, Ajou University School of Medicine, Suwon 442-749, Republic of Korea.
Kang
Su-Yeon
SY
Lee
Sang-Chul
SC
Song
Kyoung-Ju
KJ
Im
Kyung-il
KI
Shin
Ho-Joon
HJ
D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology*; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D016466:CHO Cells; D006224:Cricetinae; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D016848:Naegleria fowleri / Q000254:growth & development / Q000276:immunology / Q000472:pathogenicity*; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C460560:Nfa1 protein, Naegleria fowleri; D015800:Protozoan Proteins; D011994:Recombinant Proteins