Hemagglutination inhibition of Asian influenza viruses: A new pattern of response

Bovine and mouse serum beta inhibitors of influenza A viruses are mannose-binding lectins.

“…y inhibitors are active against human influenza A viruses of the H2 and H3 subtypes but not the H1 subtype (8,9). 'y inhibitors are present at high titer in horse and guinea pig sera and have been identified as a2-macroglobulins.…”

“…These and other properties distinguished them from the other class of serum inhibitor known at the time, the so-called Francis or a inhibitors (6), which were heat stable and inhibited hemagglutination but not virus infectivity. A third class of inhibitor, y inhibitor, was identified after the emergence in 1957 of the Asian (H2N2) influenza subtype (7,8). y inhibitors had many of the properties of a inhibitors but, like (3 inhibitors, also possessed virus-neutralizing activity.…”

The Haemagglutination Inhibitor in Edible Bird-Nest: its Biological and Physical Properties

“…for detecting cc activity. In additional tests the A2 strain A/Singapore w was included to test for y activity (Cohen & Belyavin, 1959). From time to time other strains were used as indicated.…”

“…These inhibitors have been divided into a and / 3 types on the basis of their thermostability, their sensitivity to Vibrio chobrae neuraminidase, and the strain of influenza virus most susceptible to their action . In more recent years a third class of inhibitor present in certain animal sera and characterized by its specific activity against A2 virus strains has been described (Shimojo, Sugiura, Aka0 & Enomoto, 1959;Cohen & Belyavin, 1959). This third type of inhibitor as it occurs in horse serum has been shown to be a potent infectivity-neutralizing substance in addition to its effectiveness as a simple haemagglutination inhibitor (Cohen & Belyavin, 1959).…”

“…In more recent years a third class of inhibitor present in certain animal sera and characterized by its specific activity against A2 virus strains has been described (Shimojo, Sugiura, Aka0 & Enomoto, 1959;Cohen & Belyavin, 1959). This third type of inhibitor as it occurs in horse serum has been shown to be a potent infectivity-neutralizing substance in addition to its effectiveness as a simple haemagglutination inhibitor (Cohen & Belyavin, 1959). Other naturally occurring neutralizing inhibitors have been described, notably urinary mucoprotein (Tamm & Horsfall, 1952).…”