title: Preparing hemagglutinating antigen from isolates of infectious bronchitis virus.
abstract: The hemagglutinating (HA) activity of 14 strains of infectious bronchitis virus (IBV) was investigated. The optimal conditions for IBV antigen preparation include inoculation of 10- or 11-day-old specific pathogen-free embryonated eggs and incubation for 30 hours at 37 C. Embryos were inoculated via the allantoic cavity with 0.1 ml of a low embryonic passage of the virus (10(7) to 10(8) EID50/ml). Allantoic fluid was harvested and pooled, and a 100-fold concentration of virus particles was achieved by centrifugation for 3 hours at 30,000 x g. Virus pellets were resuspended in Tris-hydrochloride buffer containing 3 units of phospholipase-C (type-1) enzyme/ml and incubated for 2 hours at 37 C. All IBV strains tested demonstrated positive HA activity with chicken red blood cells. The antigen was stored in liquid state or lyophilized at 4 C.
mesh_terms: D000818:Animals; D002642:Chick Embryo / Q000382:microbiology; D003332:Coronaviridae / Q000276:immunology*; D006386:Hemagglutination Tests / Q000662:veterinary; D006389:Hemagglutinins, Viral / Q000276:immunology / Q000302:isolation & purification*; D001351:Infectious bronchitis virus / Q000254:growth & development / Q000276:immunology*; D013047:Specific Pathogen-Free Organisms; D014776:Virus Cultivation
chemical_list: D006389:Hemagglutinins, Viral