NUCLEATED CELLS RESPONSE TO PROTEIN ELECTROINSERTION

Application of an electrical pulse field at a strength slightly below the value required for electroporation to a suspension of red blood ce lls in the presence of membrane xenoproteins leads to the insertion of those proteins in the erythrocyte plasma membrane. This observation i s extended to nucleated cells. In the presence of glycophorin A, appli cation of such pulses leads to the insertion of 10(4)-10(5) molecules of glycophorin A per cell in CEM-CM3, Hela S3, and bovine CD8+ T cells . Electroinserted glycophorin A is detected by flow cytometry using an ti-glycophorin monoclonal antibodies. The survival of the cells subjec ted to electroinsertion was 55% for CEM-CM3 cells, 69% for Hela S3 cel ls, and 65% for CD8+ T cells. Cells cultured after electroinsertion lo st the electroinserted glycophorin A, with two different rates, by a t emperature and cell type-dependent mechanism. During the first 2 h aft er electroinsertion, the CD8+ T cells lost 12.5% of the inserted glyco phorin A per h, the CEM-CM3 cells lost 7.7% per h, whereas the Hela S3 cells lost only 0.8% of the inserted protein per h. After 2 h, the ra te increased substantially, to 41.7% per h for the CD8+ T cells, 13.5% for the CEM-CM3 cells, and 8.9% for the Hela S3 cells. Cytochalasin D efficiently inhibited the disappearance of electroinserted glycophori n A during the first 2 h after electroinsertion only. (C) 1993 Wiley-L iss, Inc.