The Morphologic Characteristics of 19S Antibody

Abstract

Using foot-and-mouth-disease virus as an antigen, the negative staining technique has been employed to study the morphologic differences between 7S and 19S antibody. 7S antibody was purified by the use of diethylaminoethyl cellulose chromatography and 19S antibody by means of sucrose gradient centrifugation. Complexes were made with the virus and each of the two antibody species and examined in the electron microscope. 7S antibody appeared as a filament measuring roughly 27 × 250 Å. 19S antibody also appeared as a filament but had dimensions approximately 50 × 370 Å. Attachment to the virus particle seemed to be mainly by sites at either end of the 19S molecule but other binding sites may be present. Looping was found to be a frequent occurrence in preparations of virus and 19S antibody.