Antigen-promoted cell fusion: antigen-coated myeloma cells fuse with antigen-reactive spleen cells

We report here that the immunizing ligand, when conjugated to the membrane of the myeloma cell, selectively binds to sheep red blood cells coated with antibodies that bind the immunizing ligand. When the antigen-coated myeloma cells are incubated with spleen cells from immunized mice, fusion occurs between the myeloma cells and the spleen cells. The fusion occurs without PEG, and we have recovered stable antibody-forming cell hybrids specific for dextran and the hapten phthalate using the antigen-promoted fusion protocol described here. In most cases, the percentage of hybrids secreting antibody specific for the immunizing ligand is substantially greater than that observed with PEG.