Abstract
The relative efficiency of microcell-mediated chromosome transfer vs. somatic cell hybridization was determined. The prolonged mitotic arrest generally used to micronucleate donor [human and experimental animal] cells also reduced the fusion efficiency to 1/10th-1/5th of that in whole cell hybridizations. An alternative micronucleation protocol involving sequential treatment of the donor cells with colcemid and cytochalasin B, which yielded micronucleated cells that hybridized with the same efficiency as whole cells, is reported. The enucleation, purification and fusion steps of the microcell procedure were also refined. By using these modifications the practical yield of microcell hybrid clones can be increased 50- to 100-fold.