Improved sero-monitoring assay for classical swine fever (CSF) using the recombinant E2 protein of a recent Korean isolate.
Classical swine fever (CSF) is a highly contagious disease of pigs that causes fever, diarrhea and paralysis, often resulting in death. E2 is the major structural protein of the CSF virus (CSFV) and mediates the entrance of the virus, subsequently inducing a neutralizing immune response. In this study, the E2 gene of a recent Korean isolate of CSF, SW03, was cloned and the DNA sequence was compared to other strains via phylogenetic analysis. With the purified E2 protein, an enzyme-linked immunosorbent assay (ELISA) was developed for the serodiagnosis of CSFV infection. The sensitivity and specificity of the E2-ELISA were 96.1% and 94.8%, respectively. A total of 17 out of 485 field-collected pig sera tested demonstrated conflicting results between two ELISA methods, a commercial kit and the E2-ELISA. Of these sera, 60% were determined to be CSFV positive by a virus neutralization test (VNT), suggesting involvement of different immune responses in the cases of CSFV infection. As the E2-ELISA was developed using a recent Korean isolate, SW03, this assay is capable of rapidly identifying newly emerging CSFV strains.
Sung
Ji-Hyun
JH
Department of Infectious Diseases, College of Veterinary Medicine, KRF Priority Zoonotic Disease Research Institute and Brain Korea 21 Program for Veterinary Science, Seoul National University, Seoul 151-742, South Korea.
Kang
Mi-Lan
ML
Lee
Won-Jung
WJ
Shin
Min-Kyoung
MK
Lim
Sung-In
SI
Kim
Byoung-Han
BH
Song
Jae-Young
JY
Yoo
Han Sang
HS
D000818:Animals; D006691:Classical Swine Fever / Q000097:blood / Q000453:epidemiology / Q000821:virology*; D006692:Classical Swine Fever Virus / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics*; D012680:Sensitivity and Specificity; D012698:Serologic Tests; D013552:Swine; D014759:Viral Envelope Proteins / Q000235:genetics*
D018076:DNA, Complementary; D012367:RNA, Viral; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins; C087086:glycoprotein E2, classical swine fever virus