Cloning and expression of 51-kDa antigenic protein of Neorickettsia risticii NR-JA1.
Neorickettsia (Ehrlichia) risticii is a causative agent of acute diarrheal syndrome in horses, commonly known as Potomac horse fever. Korean isolate of N. risticii NR-JA1 was cultivated in mouse macrophage cell line P388D1. A complete ORF of p51 antigenic protein gene was amplified and cloned into pQE32 and pcDNA3.1 vectors and the resultant clones were named as pQE32/Nr-51 and pcDNA3.1/Nr-51, respectively. Recombinant p51 (rp51) protein antigen was expressed in E. coli (pQE32/Nr-51) and cos-7 cell line (pcDNA3.1/Nr-51). The rp51 protein showed immunoreactivity with anti- mouse p51 antibodies. BALB/c mice were inoculated with recombinant plasmid DNA (pcDNA3.1/Nr-51). The serum samples collected from these BALB/c mice showed IgG ELISA titers of 1:128. In a Western immunoblot assay, these serum samples showed a strong reactivity to rp51 expressed in cos-7 cell line transfected with pcDNA3.1/Nr-51. The results of this preliminary indicate that N. risticii p51 protein is an immmuno-dominant antigen and may be a good target for the development of serological or a molecular diagnostic test and possibly an improved recombinant DNA based vaccine against Potomac horse fever.
Bio-Safety Research Institute and College of Veterinary Medicine, Chonbuk National University, Jeonju 561-756, Korea.
Myeong-Kyu
MK
Park
Eun-Ha
EH
Kim
Mae-Rim
MR
Cho
Ying-Hua
YH
Yi
Mi-Jin
MJ
Lee
Devendra H
DH
Shah
Jin-Ho
JH
Park
Bae-Keun
BK
Park
Seong-Kug
SK
Eo
John-Hwa
JH
Lee
Joon-Seok
JS
Chae
D000818:Animals; D000942:Antigens, Bacterial / Q000096:biosynthesis* / Q000235:genetics* / Q000276:immunology; D000947:Antigens, Helminth / Q000096:biosynthesis* / Q000235:genetics* / Q000276:immunology; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D007941:Leukemia P388; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D041103:Neorickettsia risticii / Q000235:genetics* / Q000276:immunology*
C415977:51-kDa antigen, Ehrlichia risticii; D000942:Antigens, Bacterial; D000947:Antigens, Helminth