title: Preparation and characterization of a purified influenza virus neuraminidase vaccine.
abstract: Influenza virus neuraminidase (NA) has been shown to induce protective but infection-permissive immunity in experimental animals. Challenge infection following such immunization is attended by decreased viral replication and disease manifestations but is sufficient to provide antigenic stimulation and definitive immunity to the virus. The present report describes the preparation and characterization of a purified NA vaccine (NAV) used in Phase 1 (immunogenicity and toxicity) trials in humans. In essence, virion NA was isolated from detergent-disrupted virus by affinity chromatography on oxamic acid-agarose, treated with formalin and tested for its enzymatic activity and for its immunogenicity in Balb/c mice and New Zealand rabbits. The preparation was essentially free of viral hemagglutinin but contained residual NP and M1 proteins. Both dispersed and aggregated NA tetrameric heads were seen in electron micrographs. Enzymatic activity was preserved, and minimal immunogenic doses in mice and rabbits, respectively, were 3.7 and 0.027 micrograms per kg.
authors.affiliation: Department of Microbiology and Immunology, New York Medical College, Valhalla 10595, USA.
authors.forename: M
authors.initials: M
authors.lastname: Hocart
authors.forename: B
authors.initials: B
authors.lastname: Grajower
authors.forename: A
authors.initials: A
authors.lastname: Donabedian
authors.forename: B
authors.initials: B
authors.lastname: Pokorny
authors.forename: C
authors.initials: C
authors.lastname: Whitaker
authors.forename: E D
authors.initials: ED
authors.lastname: Kilbourne
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000276:immunology*; D005260:Female; D007252:Influenza Vaccines / Q000276:immunology* / Q000302:isolation & purification; D051379:Mice; D008807:Mice, Inbred BALB C; D008854:Microscopy, Electron; D009439:Neuraminidase / Q000276:immunology*
chemical_list: D000956:Antigens, Viral; D007252:Influenza Vaccines; D009439:Neuraminidase