Genetic manipulation by means of microcell-mediated transfer of normal human chromosomes into recipient mouse cells.

Abstract

Microcell-mediated chromosome transfer is an innovative approach to the production of karyotypically simple hybrids. This method of gene transfer, employing micronuclei formed by prolonged colcemid treatment, was utilized for rodent systems. Expansion of this technology to include transfer of normal human genetic material was hindered because large micronucleate populations from diploid human cells were unobtainable. The production of micronuclei in 40-60% of normal human fibroblasts tested is described. These micronucleated cells were enucleated by combining centrifugation and cytochalasin B treatment, and the resultant microcells were purified and fused to recipient mouse (LMTK-) cells. Microcell hybrid clones containing a single human chromosome were isolated from 3 separate fusion experiments. The time course for production of these hybrids, from fusion to karyotypic analysis, was 6 wk. With a transfer frequency of about 2 .times. 10-6, a single intact human chromosome has become a functioning element of the murine genome.