Yvonne Théry Lanni

Dialyzable Factor in Allantoic Fluid Affecting Virus Hemagglutination-Inhibition Reactions.

Summary The difference between purified and unpurified swine influenza virus with respect to development of inhibitor sensitivity on heating is ascribed to a factor, identified as calcium, occurring in, normal and virus-infected allantoic fluids. The factor, which is lost, or considerably diminished, during purification, may be removed also by dialysis or neutralized by citrate and oxalate. Calcium, in low concentration, depresses the development of inhibitor sensitivity by swine influenza virus on heating; magnesium is ineffective. In contrast with the swine virus, influenza virus A (PR8 strain) is relatively insensitive to calcium. This difference between two viruses suggests a possible explanation for the generally observed variation among influenza viruses with respect to development of inhibitor sensitivity on heating.

Reações entre caolim, virus de influenza suína e inibidor de clara de ôvo da hemoaglutinação de vírus

Kaolin adsorbs inhibitory activity more rapidly than total nitrogen from crude egg-white and less rapidly than total nitrogen from semipurified inhibitor preparations. The adsorption of inhibitoris reversible. Treatment of semipurified preparations with active swine influenza virus causes a slight increase in the adsorption of activity and total nitrogen. Active virus combines with inhibitor-coated kaolin in the cold and can be recovered in great part at room temperature. A smaller amount of virus is bound by untreated kaolin. Heating the virus for 30 minutes at 53°C increases its adsortion by kaolin.

Inhibitory Effect of Cow's Milk on Influenza Virus Hemagglutination.

Summary Milk is capable of inhibiting hemagglutination by influenza viruses, the inhibitory effect being greater against heated than against unheated viruses. The inhibitor, which is non-dialyzable and moderately heat stable, occurs in the whey and can be salted out by half-saturation with ammonium sulfate. Evidence is presented that the inhibitor is a characteristic component of milk rather than a specific antibody.