Toxin-antitoxin selection for isolating somatic cell fusion products between any cell types.

A selective system was developed that permits the isolation of heterokaryons and cell hybrids between any cell types without the use of selectable genetic markers. Antibodies were introduced into two populations of non-transformed normal diploid human fibroblasts by the osmotic lysis of pinosomes containing hypertonic antibody solutions. Heterokaryons formed by fusing antiricin-injected cells to antidiphtheria toxin-injected cells survived an overnight treatment in both ricin and diphtheria toxin. This approach should have general applicability to a variety of investigations such as the complementation analysis of human genetic syndromes, heterokaryon studies of cell differentiation, tumorigenesis and growth control, cell reconstruction experiments, and the production of hybridoma cells.