[Antigenic differences in the glycoproteins of the Newcastle disease virus].

The two glucoproteins of the Newcastle disease virus - hemagglutinin-neuraminidase (HN) and F-protein - were isolated in a pure state from two strains of the virus: the La Sota apathogenic strain and the Roussev strain pathogenic for birds. It was found that the large HN glucoprotein of each of the strains was not identical antigenically with the F-protein. These seemed to be partial antigenic relatedness between the HN of the two strains. On the other hand, the F-proteins of the strains were identical.