VISUAL IDENTIFICATION OF INDIVIDUAL TRANSFECTED CELLS FOR ELECTROPHYSIOLOGY USING ANTIBODY-COATED BEADS

Electrophysiological study of transiently transfected cells requires t he identification of individual cells that express the protein of inte rest. We describe a simple, quick and inexpensive methods for visually identifying cells that have been co-transfected with an expression pl asmid for a lymphocyte surface antigen (CD8-alpha). Transfected cells are incubated briefly with polystyrene microspheres (4.5 mu m diameter ) that have been precoated with antibody to CD8. Cells expressing CD8 on their surface are decorated with many beads and are thus readily di stinguishable from untransfected cells. Beads already coated with anti body are available commercially. The method rakes less than five minut es and requires no reagent preparation or special equipment for visual ization of the beads.