TABLE 1.

Hemagglutination inhibition titers of ISAV agglutinated with rabbit erythrocytesa

Inhibitor%bHemagglutination inhibition titer
Neu5,9Ac2Neu4,5Ac2
BSM (2 mg/ml)>35<11/512
BSM control preparation<1<11/512
Rat serumNDcND0
Rat serum control preparationNDND0
Guinea pig serum<115-201/512
Guinea pig control preparation<1<10
Horse serum<1251/1,024
Horse serum control preparation<1<10
Rabbit serumND51/256
Rabbit serum control preparationND<10
  • a Four hemagglutination units of virus was incubated with serially diluted inhibitor, followed by addition of 0.75% rabbit erythrocytes. Control preparations of each inhibitor were made by removal of O-acetyl groups by mild alkali treatment.

  • b Data indicate the ratio of O-acetylated sialic acids to the total sialic acid content.

  • c ND, not determined.