Construction of Neospora caninum stably expressing TgSAG1 and evaluation of its protective effects against Toxoplasma gondii infection in mice.
Toxoplasma gondii and Neospora caninum are closely related apicomplexan parasites. The surface antigen 1 of T. gondii (TgSAG1) is a major immunodominant antigen and, therefore, is considered to be a good candidate for the development of an effective recombinant vaccine against toxoplasmosis. In this study, N. caninum stably expressing the TgSAG1 gene (Nc/TgSAG1) was constructed using pyrimethamine-resistant DHFR-TS and GFP genes as double-selection markers. The expression level, molecular weight, and antigenic property of recombinant TgSAG1 expressed by the Nc/TgSAG1 were similar to those of the native TgSAG1. The mice immunized with Nc/TgSAG1 induced TgSAG1-specific Th1-dominant immune responses and protected the mice from a lethal challenge infection with T. gondii. These results indicate that N. caninum may provide a new tool for the production of a live recombinant vector vaccine against toxoplasmosis in animals. To our knowledge, this is the first report to evaluate the usefulness of N. caninum-based live vaccine.
Zhang
Guohong
G
National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
Huang
Xiaohong
X
Boldbaatar
Damdinsuren
D
Battur
Banzragch
B
Battsetseg
Badgar
B
Zhang
Houshuang
H
Yu
Longzheng
L
Li
Yan
Y
Luo
Yuzi
Y
Cao
Shinuo
S
Goo
Youn-Kyong
YK
Yamagishi
Junya
J
Zhou
Jinlin
J
Zhang
Shoufa
S
Suzuki
Hiroshi
H
Igarashi
Ikuo
I
Mikami
Takeshi
T
Nishikawa
Yoshifumi
Y
Xuan
Xuenan
X
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D005260:Female; D056724:Immunity, Humoral; D016056:Immunodominant Epitopes / Q000235:genetics / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D018688:Neospora / Q000235:genetics*; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D016052:Protozoan Vaccines / Q000276:immunology*; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D014122:Toxoplasma / Q000276:immunology; D014124:Toxoplasmosis, Animal / Q000276:immunology / Q000517:prevention & control*; D014162:Transfection
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016056:Immunodominant Epitopes; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D011994:Recombinant Proteins; C047168:SAG1 antigen, Toxoplasma