Choi Kang-Seuk, Kye Soo-Jeong, Kim Ji-Ye, Seul Hee-Jeong, Lee Hee-Soo, Kwon Hyuk-Moo, Sung Haan-Woo
OIE Reference Laboratory for Newcastle Disease, Avian Diseases Division, Animal and Plant Quarantine Agency, Anyang 430-757, Republic of Korea.
College of Veterinary Medicine & Institute of Veterinary Science, Kangwon National University, Chuncheon, Kangwon 200-701, Republic of Korea.
J Virol Methods. 2014 Mar;198:12-7. doi: 10.1016/j.jviromet.2013.12.010. Epub 2013 Dec 24.
Avian paramyxovirus 2 (APMV-2) infections are associated with respiratory diseases in poultry worldwide. The hemagglutination inhibition (HI) test is a useful tool for surveillance and monitoring of this virus. In this study, full-length hemagglutinin (HN) gene of APMV-2 was chemically synthesized based on its published sequence, cloned and expressed in Spodoptera frugiperda insect cells using recombinant baculoviruses. The biological, antigenic and immunogenic properties of the expressed protein were evaluated to assess its ability to produce diagnostic reagents for HI testing. Recombinant APMV-2 HN protein showed two distinct bands with molecular masses of 64 and 75kDa, which showed hemagglutination (HA) and neuraminidase activities, respectively. The recombinant HN (rHN) protein extracted from infected cells produced high HA titers (2(13) per 25μL). HA activity of the protein was inhibited by APMV-2 antiserum, although there were weak cross reactions with other APMV serotype antisera. The rHN protein induced high titers of APMV-2-specific antibodies in immunized chickens based on the HI test. These results indicated that recombinant APMV-2 HN protein is a useful alternative to the APMV-2 antigen in HI assays.
