The application of the fluorescent-antibody technique to haemagglutinating systems

The Coons' technique has been modified for the detection of antibodies on erythrocytes agglutinated by fluorescein-conjugated antisera. The results of experiments with several haemagglutinating systems suggested that specific fluorescence was found only on erythrocytes which had been agglutinated by species-specific antibodies. The significance of these findings is discussed.