Studies on the Major Common Precipitating Antigen of Capripoxvirus

Western blot analysis of virus-specific antibody responses for capripox and contagious pustular dermatitis viral infections in sheep

“…The soluble antigens used in AGID tests were prepared from tissue cultures and scabs, thus it was difficult to determine whether cross-reactive antibodies were directed against structural or non-structural proteins of the virus. A major common precipitating antigen (67 kDa) found in all CPV that also reacts with CPDV serum has been reported to be a viral envelope protein [8].…”

“…The CPV used for the study was a Kenya sheep and goat pox isolate (KS-1) that had been developed for a vaccine [8]. The CPDV was obtained from an infected sheep as a dried scab ground in sterile sand supplied by Dr G. R. Scott of the Centre for Tropical Veterinary Medicine, Edinburgh, UK.…”

“…The KS-I isolate of CPV was grown on secondary lamb testis cell monolayers in 175 cm2 flasks and purified as described by Kitching and colleagues [8]. CPDV was purified from scabs obtained from an experimentally inoculated sheep.…”

“…The supernatant was used as an antigen in the AGID test. Soluble antigen from CPV was also prepared as described previously [8] for use in the AGID test.…”

“…The viruses can easily be differentiated from each other by electron microscopy [6], and genomic comparison [7]. However, a major common precipitating antigen shown to be present in strains of CPV also reacts with CPDV positive serum [8]. Many serodiagnostic assays such as agargel immunodiffusion, complement-fixation, counter-immunoelectrophoresis, or ELISA, because they detect total antibody response including that from cross-reactive antibodies, are not reliable for differention between these infections.…”