FLUORESCENCE OF EOSINOPHIL LEUKOCYTE GRANULES INDUCED BY THE FLUOROGENIC REAGENT 2-METHOXY-2,4-DIPHENYL-3 (2H)-FURANONE

The fluorogenic reagent MDPF forms highly fluorescent products specifi cally with primary amino groups (e.g., from lysine). Although widely u sed in analytical biochemistry, MDPF has infrequently been employed in cytochemical techniques for proteins. In this work, we describe the a pplication of MDPF in fluorescence microscopy studies of horse, rat, a nd human blood cells. Under ultraviolet excitation, MDPF selectively i nduces an intense white-blue fluorescence reaction in the granules of eosinophil leukocytes, which contain strongly basic proteins. The adva ntages of MDPF for identification to reveal protein components in hema tological cytochemistry are briefly discussed.