Detection and quantitation of cell-cell electrofusion products by flow cytometry

A cytometric method for detecting and quantitating hybrid cells that resulted from cell-cell electrofusion was developed. Cells from two different lines and two vital fluorescent dyes were used in conjunction with a flow cytometer to demonstrate the method. Each dye was used to stain one cell type prior to electrofusion. Hybrid cells exhibited dual fluorescence while unfused cells retained their single fluorescence. Flow cytometry was used to detect dual fluorescing hybrid cells that resulted from electrofusion. Fluorescent microscopy was used to confirm that 92% of the cytometrically detected cells were hybrids. Flow cytometry was also used to quantitatively show differences in hybrid yields for samples fused using different electrical conditions. These results demonstrate that the method can be used for detection and quantitation of electrofusion products. The methodologies presented are not specific to the cell types used; they can be adapted for use with other cell types.