The Sedimentable Components of Influenza Virus Propagated in Deembryonated Eggs

Abstract

The PR8 strain of type A influenza virus diluted to 10⁻¹ or 10⁻⁵ with Tyrode's solution was propagated in deembryonated eggs. The preparations obtained in this manner were concentrated by ultracentrifugation, examined in the analytical ultracentrifuge and tested for hemagglutinating and infectious capacities. It was found that preparations obtained when the inocula were diluted 10 times were of low infectivity, moderately high hemagglutinating capacity and contained one major component sedimenting at approximately 480 S. Preparations obtained when the inocula were diluted to 10⁻⁵ also contained only one major component, but this exhibited a sedimentation constant of approximately 630 S, a high infectivity, and the hemagglutinating capacity was comparable to that of the 480 S preparations. It has been concluded from these and from other data that the infectious principle of the PR8 strain of Type A influenza virus resides primarily in the heavy component, while the hemagglutinative capacity is distributed between heavy and light components.