Use Of Somatic Cell Hybrids Research Articles

Molecular cloning and chromosomal assignment of the human homolog of int-1, a mouse gene implicated in mammary tumorigenesis.

Viral mammary tumorigenesis in mice is frequently initiated by proviral activation of a highly conserved cellular gene called int-1. We have cloned the human homolog of this putative mammary oncogene and compared its structure to that of the mouse gene by heteroduplex analysis. The human int-1 gene was localized on chromosome 12 by use of somatic cell hybrids.

Antisera Recognising HLA‐A, ‐B and DRW Antigens Raised in Rhesus Monkeys

Rhesus monkeys were immunized with partially purified HLA-A, -B, -C and DR antigens. The resulting sera were shown to have activity against species-specific determinants on both HLA-A, -B, -C chains and beta 2 microglobulin by the use of somatic cell hybrids. When this was removed by absorption, the sera showed activity against three of the four HLA-A and -B antigens in the immunogen when tested on a panel of peripheral blood lymphocytes and T cells. Antibodies recognizing HLA-DR antigens were detected by testing platelet absorbed sera on a panel of typed lymphoblastoid cell lines. After absorption to remove activity against species-specific determinants on the HLA-DR antigens, two cross reacting specificities were defined. One consisted of a determinant in common between HLA-DRw1, 2 and 6 and the other a putative determinant in common between HLA-DRw4, and 5. The nature and significance of these cross-reacting groups of HLA-DR antigens is discussed in the light of current HLA-DR serology and the nature of HLA antigens in general.

A standard procedure for gene assignment by use of somatic cell hybrids.

A standard procedure for gene assignment by use of somatic cell hybrids.

A human chromosomal determinant for susceptibility to herpes simplex virus.

THE susceptibility of mammalian cells to virus infection has been studied in many virus–host systems. In certain instances1–6, the comparison of cells which do not permit productive infection with those that do has made it possible to identify the host factors which allow entry of the virus and support its subsequent growth. In the case of poliovirus the use of somatic cell hybrids between permissive and non-permissive cells has led to the assignment to human chromosome 19 of a gene coding for virus susceptibility7. Although cells from a wide variety of organisms, including many rodents and man, are susceptible to lytic infection by herpes simplex virus type 1 (HSV-1) resistance to HSV-1 infection has been reported in certain Chinese hamster cell lines8–10, in dog kidney cells11, and in a line of rat cells12. In these cell lines HSV-1 is either non-infectious or exhibits virus titres several orders of magnitude lower than in Syrian hamster or rabbit cells. The cellular factors involved in this resistance to infection and in the genetic control of susceptibility to HSV-1 have not yet been identified.

Use of somatic cell hybrids for analysis of the differentiated state.

Use of somatic cell hybrids for analysis of the differentiated state.

Use of somatic cell hybrids for analysis of the differentiated state.

Use of somatic cell hybrids for analysis of the differentiated state.

Cytological mapping of human X-linked genes by use of somatic cell hybrids involving an X-autosome translocation (mouse-hamster-human X-linked markers).

Man-mouse and man-Syrian hamster somatic hybrid cell lines were prepared by fusion of mouse A9 or hamster TG2 cells, which are deficient in hypoxanthine-guanine phosphoribosyl transferase, with cells of a diploid fibroblastic strain, KOP-1, derived from a woman heterozygous for an X-autosome translocation. 61 clones were derived in nonselective medium and 85 sublines of these were derived in selective media: 53 in hypoxanthine-aminopterine-thymidine and 32 in 8-azaguanine. All three human X-linked markers studied, i.e., hypoxanthineguanine phosphoribosyl transferase (EC 2.4.2.8), glucose-6-phosphate dehydrogenase (EC 1.1.1.49), and phosphoglycerate kinase (EC 2.7.2.3), were present together, or absent together, in most of these clones and sublines. However, loss or retention of only phosphoglycerate kinase was occasionally observed, even in the absence of selective growth, while no evidence of separation of hypoxanthine-guanine phosphoribosyl transferase from glucose-6-phosphate dehydrogenase occurred. Cytological examination of eight man-hamster clonal lines by the quinacrine fluorescent technique showed that human phosphoglycerate kinase was only present when the translocation chromosome carrying most of the long arm of the X chromosome was present. The presence of human glucose-6-phosphate dehydrogenase and hypoxanthine-guanine phosphoribosyl transferase was not related to the presence or absence of this chromosome, but appeared to be correlated with the presence of the other translocation chromosome.