Cytogenetics and the major histocompatibility complex in a proliferating microcell-mediated hybrid clone

Summary By way of a microcell fusion, three chromosomes from a B82HTQ2 (TK^–) cell were introduced into a PG19 (HGPRT^–) cell. Analysis of this hybrid clone showed that the transferred chromosomes restored a positive HGPRT status but failed to produce heterozygosity for the major histocompatibility complex (H-2). The three chromosomes also proved stable in both long term culture in vitro and tumor testing in mice. It is suggested that the method could prove useful in correcting genetic defects or in introducing new genetic characteristics without the introduction of the genes coding for major histocompatibility antigens. The surface structure of the microcells was studied by scanning electron microscope. The optimum for induction of the microcells from B82HTQ2 cells and its' purification were reported here. Frequency of the sister chromatid exchange (SCE) of the hybrid cells and their sensitivity to mitomycin C (MMC) were also examined.