The autoradiographic localization of intracellular antibody.

A method developed for localizing antibody in imprints of lymphoid organs of immunized animals involves treating the fixed imprints with radio-iodinated homologous antigen, washing to remove uncombined antigen and then making an autoradiograph. Finally the imprints are stained with the autoradiographic film . A number of artefacts interfere with this procedure, and steps have been taken to overcome them. Antibody is localized by this method in plasma cells. The number of grains over an individual cell is proportional to the amount of radioactive material it has fixed, so that the method is potentially capable of yielding quantitative results.