Studies on Molecular Biology, Monoclonal Antibody and Cross-Protectivity of Newcastle Disease Virus

• Main Authors: Chao-Chuan Huang, 黃兆銓
• Other Authors: Maw-Yeong Lin
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/58059741112840701262

碩士 === 國立屏東科技大學 === 生物科技研究所 === 92 === Newcastle disease (ND) is a highly contagious viral disease in causing respiratory, digestive and nervous disturbance in domestic poultrys and birds. Phylogenetical analysis of the 13 isolates ND virus (NDV) of 2002-2003 year (TW02-TW/03) revealed that 9 and 2 isolates providing the sequence 112RRQKR/F117 and 112RRKKR/F117 respectively at the cleavage site of the F glycoprotein was grouped into subgenotype VIId, viscerotropic velogenic NDV (VVNDV). The nucleotide sequence of the 11 isolates VVNDV had 3.5-5.3% difference with China VVNDV isolates. The nucleotide sequence of the remaining 2 isolates were grouped into subgenotype II of lentogenic type. Which provided 1.1-4.6% difference in nucleotide sequence with the lentogenic vaccine strains. In vitro evaluation the level of cross reactivity in hemagglutination- inhibition (HI) test revealed that all the TW/02-TW/03 isolates had high level of cross HI reaction among them; moderated cross reactivity with 6 of 1999 Taiwan VVNDV Isolates (TW/99) and 1 of 1984 Taiwan isolate and very mild cross reactivity with the 2 TW/02 and TW/03 isolates of lentogenic type NDV. In vivo evaluation the cross protectivity of TW/02-TW/03 isolates against the TW/02-TW/03 isolates challenge revealed that the group of the chickens immunized with the inactivated vaccine prepared from the TW/02-TW/03 VVNDV isolates gave less HI antibody jump after challenge. Result of the in vitro and in vivo evaluation imply that the newly VVNDV isolates had high antigenic variance on HN gene. A good cross protection commercial ND inactivated vaccine now a day has to be prepared from them. Ten monoclonal antibodies (mAb) prepared from TW/99-V157 isolates were used for serotyping the 23 isolates or strains of NDVs stocked in this laboratory. TW/02-isolates provided a great antigenic variance at the site 1, 2 and 3 of the F glycoprotein. HN gene of NDV was cloned in the vector of baculovirus expression system and the expressed NDV-rHN glycoprotein was firmly proved with Western blot mast production of the glycoprotein shall be done in this laboratory for further research works.