The Preparation Of The Monoclonal Antibodies To The Fusion Protein Of The Newcastle Disease Virus

Chinese challenge strain F48E8 of newcastle disease virus(NDV) was papagated in the allantoic cavity of 10-day old embiyonated SPF chicken eggs. The allantoic fluid of NDV F48E8 was purified and concentrated by centrifugation with 10-60% continuous sucrose gradient. The indirect ELISA was developed by using the purified NDV as antigen and used to screen monoclonal antibodies (MAbs). Recombinant fowlpox vivus(rFPV) were selected and purified many times in chicken embryo fibroblast (CEF) cultures overlaid with agarose gel containing x-gal by blue plaques screening. The expression of the NDV F gene in recombinant FPV was confirmed by indirect immunofluorescence(IIF) with ployclonal chicken antiserum against NDV. The 1W with the CEF infected by the purified rFPV as the second screening system was used to select the clones which had been positive in indirect ELISA. The BALBIC mice were immunized by the intact NDV and the F protein of the sodium dodecyl sufate 梩reated NDV (SD SNDV). By using the hybridoma technique seven MAbs with specificity to the NDV F protein were established. They were named C5-2-A7, F7-G5, F9-2-G5, B2-C8-F10, Ci 1-C6-E2, 55-C2- A9, 51 -F6-F7 respectively. The first five MAbs were derived from fusions with the intact NDV as immunogen, and the other two were abtained from the F protein of the SDSNDV. All of the MAbs were negative in HI test while only three of them neutralized viral infectivity in embryonated eggs. The first five of them bound to the virus at higher titers than the others in indirect ELISA. These MAbs were able to recognize the protein about 56KD in western blot with the exception of the Mabs F7-G5 ,C11-C6-E2. The reacting patterns of MAbs with different NDV strains indicated that all of the MAbs were against the conserved antigenic epitopes of the F protein of NDV.