A new fluorochromasia method using a fluorescence microplate reader for assay of cytotoxic activity of carp leucocytes

A new fluorochromasia method using a fluorescence microplate reader has been established to assay spontaneous cytotoxic activity of carp leucocytes. This method is characterized by using propidium iodide (PI) for staining dead target cells and a fluorescence microplate reader for measurement of the fluorescence of PI. K562 as target cells were prepared in 96-well flat-bottom microplates, and carp leucocytes were added as effector cells. After 2.5 h incubation, PI was added to each well. After an additional 1.5 h incubation, fluorescence of each well was measured. ation between this method and 51Cr-release assay was obtained. The results demonstrated that this new fluorochromasia method can be used to assay cytotoxic activity of carp leucocytes.