Site of the Chorioallantoic Inhibitor of Influenza Virus Hæmagglutinin

Abstract

THE chorioallantoic inhibitor of influenza virus hæmagglutinin is destroyed during the multiplication of influenza virus in the allantois^1–3. It is not, however, destroyed by V. cholerae receptor-destroying enzyme inoculated into the allantoic cavity⁴, and only partly destroyed when the chorioallantois is exposed to the enzyme in vitro ^1,4. Because of this inaccessibility to receptor-destroying enzyme the inhibitor has been taken by most workers to be inside the allantoic cells and therefore potentially an index of the intracellular action of influenza virus enzyme. For example, the finding that massive inocula of virus inactivated by ultra-violet do not destroy the inhibitor has prompted the suggestion² that infecting particles lose their enzyme on entering the cell, the only virus enzyme to occur inside cells being that of progeny particles.