Attachment of Antibody to Influenza Virus

Abstract

A KINETIC analysis of the neutralization of influenza virus by rabbit antibody indicated that the combination proceeds in two stages¹. The first stage is the formation of a freely dissociable union between the virus and antibody. This is followed by a second stage which leads to the stabilization of the complex between the virus and antibody. The reaction kinetics also indicated that a single antibody molecule could form a stable combination with the virus particle. In an attempt to elucidate the nature of the stage of stabilization, the interaction between influenza virus and the univalent antibody fragments, produced by papain digestion², was investigated³. This investigation demonstrated that although the monovalent fragments could combine reversibly with the virus and neutralize its infectivity, they were unable to form a stable combination with the virus. It could be concluded that the stabilization of the combination between the virus and antibody depended on the divalent nature of the antibody molecule. On the basis of the foregoing conclusions and observations the following hypothesis emerged. The first stage in neutralization would be the attachment of the antibody molecule to the surface of the virus through one combining site and the second and stabilizing stage would be brought about by the attachment of the second combining site on the divalent antibody molecule to the same virus particle.