The structure of the hemagglutinin, a determinant for the pathogenicity of influenza viruses

摘要: Abstract Comparative studies on naturally occurring avian influenza viruses have been carried out in order to investigate the determinant(s) for pathogenicity chickens. At least one virus isolate from each of nine different hemagglutinin (HA) subtypes was included. The polypeptides these were studied by analyzing infected cell extracts SDS-polyacrylamide gels. Both viral glycoproteins, HA and neuraminidase, showed remarkable variation their electrophoretic mobility even among serologically closely related viruses. Pulse-chase experiments revealed that most strains had an which not susceptible proteolytic cleavage MDCK, turkey (TEC), chicken embryo cells (CEC). Only belonging subtype Hav5 some Hav1 possessed a cleaved cells. with produced infectious form CEC, TEC, as well duck (DEC) quail (QEC). other plaques only presence trypsin. There strict correlation between cleavability HA, potential be wide range host cells, No evidence obtained involvement neuraminidase determining pathogenicity. For nonpathogenic it could shown they can replicate produce progeny organs chicken. results permit conclusion structure hemagglutinin, is its susceptibility broad spectrum factor