Biomaterial Database

Serotyping of avian infectious bronchitis viruses by the virus-neutralization test. 1975

B S Cowen, and S B Hitchner

The antigenic relationships of 12 strains of infectious bronchitis virus (IBV) were evaluated by a virus-neutralization procedure similar to that used in typing human rhinoviruses. Such a procedure consists of reciprocal neutralization tests performed by reacting 32-320 EID50 or plaque-forming units of virus with 20 antibody units of antiserum. Eight serologic groups were identified by chicken embryo assay, and 4 by plaque-reduction (90%). In general, serologic groupings were not distinct but reflected numerous intergroup relationships. The contrasting results exhibited by indicator systems are viewed as differences in the accuracy of the methods employed. It is suggested that before an IBV classification scheme can be proposed, agreement must be reached on the most suitable indicator system, techniques must be standardized, and reference viruses and antisera distributed to several institutions for comparison testing. In addition, cross-protection studies are needed to determine the importance of IBV serotypes and/or variants on vaccine efficacy.

UI	MeSH Term	Description	Entries
D009500	Neutralization Tests	The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).	Neutralization Test,Test, Neutralization,Tests, Neutralization
D010948	Viral Plaque Assay	Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.	Bacteriophage Plaque Assay,Assay, Bacteriophage Plaque,Assay, Viral Plaque,Assays, Bacteriophage Plaque,Assays, Viral Plaque,Bacteriophage Plaque Assays,Plaque Assay, Bacteriophage,Plaque Assay, Viral,Plaque Assays, Bacteriophage,Plaque Assays, Viral,Viral Plaque Assays
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick
D003332	Coronaviridae	Spherical RNA viruses, in the order NIDOVIRALES, infecting a wide range of animals including humans. Transmission is by fecal-oral and respiratory routes. Mechanical transmission is also common. There are two genera: CORONAVIRUS and TOROVIRUS.	Bafinivirus,Coronavirinae,Torovirinae,White bream virus,Bafiniviruses,White bream viruses
D003429	Cross Reactions	Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.	Cross Reaction,Reaction, Cross,Reactions, Cross
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000956	Antigens, Viral	Substances elaborated by viruses that have antigenic activity.	Viral Antigen,Viral Antigens,Antigen, Viral
D001351	Infectious bronchitis virus	A species of CORONAVIRUS causing infections in chickens and possibly pheasants. Chicks up to four weeks old are the most severely affected.	Avian Infectious Bronchitis Virus,Infectious Bronchitis Virus, Avian,Infectious bronchitis viruses,bronchitis viruses, Infectious
D012703	Serotyping	Process of determining and distinguishing species of bacteria or viruses based on antigens they share.	Serotypings