Biomaterial Database

[Improved method of determining the infectivity of the influenza virus]. 1981

O P Zhirnov, and A V Ovcharenko, and A G Bukrinskaia

The infectious activity of influenza A virus preparations with different ratios of unsplit (HA) and split (HA1 + HA2) hemagglutinin was studied. For this purpose the virus was cultivated in chick embryos (the virus with split hemagglutinin), chick fibroblast culture (unsplit hemagglutinin) and in chick fibroblast culture to the medium of which chick embryo allantoic fluid was added (partially split hemagglutinin). Proteins were analysed by polyacrylamide gel electrophoresis followed by the scanning of the gels. An improved plaque method in cell cultures under the agar overlay was used to assay the infectious activity of the virus preparations. This method gave more accurate determinations of the infectious titre of the preparations tested. The routine titration method gave higher infectious titres of the preparations particularly for the virus with unsplit hemagglutinin. Employing the new method, a ratio of infectious and physical particles in preparations with different HA/HA1 + HA2 contents was determined and the productive activity of cells of the chorioallantoic membrane in chick embryos and chick fibroblast cell cultures infected with influenza virus was evaluated.

UI	MeSH Term	Description	Entries
D009980	Influenza A virus	The type species of the genus ALPHAINFLUENZAVIRUS that causes influenza and other diseases in humans and animals. Antigenic variation occurs frequently between strains, allowing classification into subtypes and variants. Transmission is usually by aerosol (human and most non-aquatic hosts) or waterborne (ducks). Infected birds shed the virus in their saliva, nasal secretions, and feces.	Alphainfluenzavirus influenzae,Avian Orthomyxovirus Type A,FLUAV,Fowl Plague Virus,Human Influenza A Virus,Influenza Virus Type A,Influenza Viruses Type A,Myxovirus influenzae-A hominis,Myxovirus influenzae-A suis,Myxovirus pestis galli,Orthomyxovirus Type A,Orthomyxovirus Type A, Avian,Orthomyxovirus Type A, Human,Orthomyxovirus Type A, Porcine,Pestis galli Myxovirus,Fowl Plague Viruses,Influenza A viruses,Myxovirus influenzae A hominis,Myxovirus influenzae A suis,Myxovirus, Pestis galli,Myxoviruses, Pestis galli,Pestis galli Myxoviruses,Plague Virus, Fowl,Virus, Fowl Plague
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
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D006387	Hemagglutination, Viral	Agglutination of ERYTHROCYTES by a virus.	Hemagglutinations, Viral,Viral Hemagglutination,Viral Hemagglutinations
D006389	Hemagglutinins, Viral	Specific hemagglutinin subtypes encoded by VIRUSES.	Viral Hemagglutinin,Viral Hemagglutinins,Hemagglutinin, Viral
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
D014764	Viral Proteins	Proteins found in any species of virus.	Gene Products, Viral,Viral Gene Products,Viral Gene Proteins,Viral Protein,Protein, Viral,Proteins, Viral
D014776	Virus Cultivation	Process of growing viruses in live animals, plants, or cultured cells.	Viral Cultivation,Cultivation, Viral,Cultivation, Virus,Cultivations, Viral,Cultivations, Virus,Viral Cultivations,Virus Cultivations