title: ELISAs based on rNcGRA7 and rNcSAG1 antigens as an indicator of Neospora caninum activation.
abstract: Bovine abortion caused by the Apicomplexa parasite Neospora caninum is a major economical problem in the livestock industry worldwide. However, the relationship between N. caninum infection and abortion is still unknown. Our study aimed to elucidate the relationship between parasite-specific antibody responses, parasite stages and abortion. In experimentally infected cattle, anti-NcGRA7 IgG1 antibody was predominantly detected during the acute infection stage, while the production of anti-NcSAG1 IgG1 antibody was observed during both acute and chronic stages. Furthermore, levels of anti-NcGRA7 IgG2 antibody were lower than those of anti-NcSAG1 IgG2 antibody. When tested on cattle with Neospora-associated abortion, positive rates of the anti-NcGRA7 IgG2 antibody were significantly lower than those of the anti-NcSAG1 antibody, although there was no difference in IgG1 antibody-positive rates between the two antigens. In addition, anti-NcGRA7 IgG2 antibodies were not detected in cattle for more than 30days after abortion. Our results suggested that anti-NcGRA7 and anti-NcSAG1 antibodies are suitable indicators for the activation stage of N. caninum infection and broad detection of the infection, respectively. In conclusion, the use of recombinant NcGRA7 and NcSAG1-based ELISAs will be useful for evaluating the abortion risk associated with N. caninum infection.
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Hiasa
authors.forename: Junko
authors.initials: J
authors.lastname: Kohara
authors.forename: Maki
authors.initials: M
authors.lastname: Nishimura
authors.forename: Xuenan
authors.initials: X
authors.lastname: Xuan
authors.forename: Hiromi
authors.initials: H
authors.lastname: Tokimitsu
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Nishikawa
mesh_terms: D000034:Abortion, Veterinary; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood / Q000145:classification; D000953:Antigens, Protozoan / Q000097:blood / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000175:diagnosis / Q000469:parasitology*; D003048:Coccidiosis / Q000097:blood / Q000175:diagnosis / Q000469:parasitology / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D005260:Female; D007074:Immunoglobulin G / Q000097:blood / Q000145:classification; D018688:Neospora / Q000502:physiology*; D011247:Pregnancy; D015800:Protozoan Proteins / Q000097:blood* / Q000276:immunology; D013997:Time Factors
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D015800:Protozoan Proteins