title: Influenza virus pyrogenicity: central role of structural orientation of virion components and involvement of viral lipid and glycoproteins.
abstract: Ultraviolet light-inactivated, non-infectious influenza virus is pyrogenic; virion components are probably responsible for this pyrogenicity. To try to identify the pyrogenic component, influenza virions were disrupted with either bromelain or sodium deoxycholate (DOC). Treatment of infectious virions with bromelain, under conditions that removed the surface glycoproteins (spikes), destroyed their pyrogenicity. The supernatant, containing non-aggregated and modified glycoproteins, was also non-pyrogenic. Disruption of virions with DOC considerably reduced pyrogenicity; however, some was retained by the sub-viral cores. Viral nucleoprotein and matrix protein, purified from the supernatant, were non-pyrogenic. Aggregated stellate clusters of surface glycoproteins separated on sucrose gradients were pyrogenic in half of numerous tests performed with different batches of material. Treatment of virus with ether resulted in complete loss of pyrogenicity. Liposomes made from extracted viral lipid were non-pyrogenic. In contrast, virosomes made from the viral lipid and the aggregated stellate clusters of surface glycoproteins were pyrogenic. Hence, optimum pyrogenicity depends upon the integrity of the virus particle, but haemagglutinin and/or neuraminidase appear essential, and lipid may be involved.
authors.affiliation: Microbial Molecular Genetics and Cell Biology Research Group, School of Biological Sciences, University of Birmingham, U.K.
authors.forename: J M
authors.initials: JM
authors.lastname: Pickering
authors.forename: H
authors.initials: H
authors.lastname: Smith
authors.forename: C
authors.initials: C
authors.lastname: Sweet
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001963:Bromelains / Q000494:pharmacology; D003840:Deoxycholic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005289:Ferrets; D005334:Fever / Q000382:microbiology*; D009980:Influenza A virus / Q000502:physiology* / Q000648:ultrastructure; D008055:Lipids / Q000502:physiology*; D008081:Liposomes / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron; D009976:Orthomyxoviridae Infections / Q000503:physiopathology*; D011749:Pyrogens; D014759:Viral Envelope Proteins / Q000502:physiology*
chemical_list: D008055:Lipids; D008081:Liposomes; D011749:Pyrogens; D014759:Viral Envelope Proteins; D003840:Deoxycholic Acid; D001963:Bromelains