Enzymic Action of Influenza Virus on Human Erythrocyte Stroma Components.

Abstract
The presence in human erythrocyte stroma of a chromogenic substance giving absorption spectra (direct Ehrlich and Bial reactions) identical with those of crystalline sialic acid was confirmed. A potent water-soluble inhibitor of viral hemagglutination, containing 7-11% by weight of this chromogen, was isolated by partition dialysis from concentrated human erythrocyte stroma. Of the chromogen 30-40% in the crude stroma concentrate and up to 56% of that in the purified inhibitor was rendered dialyzable following treatment with concentrated infective influenza virus, which in most instances also destroyed receptors for indicator viruses. Limited chromatographic analysis indicated that the dialyzable chromogen is most probably sialic acid. These observations represent the first direct demonstration of split products resulting from enzymic action of influenza virus on human erythrocyte components.