Localization of antigen in tissue cells; improvements in a method for the detection of antigen by means of fluorescent antibody

Improvements in a method for the specific microscopic localization of antigen in tissue cells are described. This method employs antibody labelled with fluorescein isocyanate as a histochemical stain, the specific antigen-antibody precipitate being made visible under the fluorescence microscope. Two isomeric series derived from nitrofluorescein are described.