ISSN:1424-8581    

DOI:10.1159/000131487

出版商:S. Karger AG    

年代:1980

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000131488

出版商:S. Karger AG    

年代:1980

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000131489

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Characteristic rearranged human chromosome markers have been observed in a variety of HeLa cell sublines and in five suspected HeLa contaminant lines originally thought to be derived from differentiated tissues of different individual patients. The allozyme genetic signatures, representing the composite enzyme phenotype at eight polymorphic loci, of each of the studied contaminant lines were identical to each other and to those of HeLa cells. The probability that each of these lines would have an identical genetic signature (since the frequency of the HeLa genotype is 0.0017) is 4.2×10–15. Differences between cell lines, however, could be detected by isoelectric focussing of the isoenzymes for glucose-6-phosphate dehydrogenase. The cell lines, including CLL 74, the older Chang liver line, failed to express five liver-specific proteins. One protein was detected in a new liver cell culture. Variations in cytogenetic, biochemical, and differentiated functions during continuous cell culture are discuss

ISSN:1424-8581    

DOI:10.1159/000131490

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Concordant segregation of human brain-type creatine kinase, CK(BB), expression with nucleoside phosphorylase (NP) expression and the presence of chromosome 14 was observed in 53 independently derived cell hybrids between CK(BB)-positive human cells and CK(BB)-negative rodent cells. Further analysis of 26 subclones of two CK(BB)-positive human-mouse cell hybrids confirmed the positive correlation of CK(BB) expression with NP expression. The results suggest that the gene coding for human CK(BB) can be assigned to chromosome 14.

ISSN:1424-8581    

DOI:10.1159/000131491

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

The chromosome localization and gene synteny of the major histocompatibility complex (MHC) of the great apes and rhesus monkey were investigated using somatic cell hybrids. The presence of the MHC antigens was determined either with a microadsorption technique employing primate alloantisera, or with a radioimmune assay. The enzymes phosphoglucomutase 3 (PGM3), glyoxalase 1 (GLOl), mitochondrial superoxide dismutase (SOD2), and soluble maleic enzyme (ME1) were assayed in those hybrids where electrophoretic separations could be achieved. A chromosome homologous to the human No. 6 was found in the chimpanzee, gorilla, orangutan and rhesus monkey, and its genomic organization is similar to that of man.

ISSN:1424-8581    

DOI:10.1159/000131492

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

The order of termination of DNA replication of ten human chromosomes remaining in a hybrid between normal human skin fibroblasts and mouse RAG cells has been analyzed. The human chromosomes were Nos. 2, 3, 4, 5, 6, 7, 10, 16, 17 and the Y. The order of replication of these chromosomes was essentially the same as that of the corresponding chromosomes in normal fibroblasts. This hybrid contained four human chromosomes, 6, 16, 17, and the Y, which were not present in a related hybrid (RRP5-4) which had been studied previously. Several chromosomes in RRP5-4, including 4, 5, and 7, had been shown to replicate at different times than the same chromosomes in the normal parental fibroblasts. These results suggest that there may be specific genes which are important for the control of the precise order of replication of human fibroblast chromosomes. These genes could be located on chromosomes which were retained in the hybrid analyzed here but which were missing from RRP5-4.

ISSN:1424-8581    

DOI:10.1159/000131493

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Cell hybrids between nontumorigenic human diploid and tumorigenic heteroploid cells of the D98AH2 strain initially contain a complete or nearly complete chromosome complement of both parental lines. Of 35 such independent isolates all failed to form tumors when inoculated at 146 different sites in nude mice, even at cell doses 40 fold greater than those at which D98AH2 cells produce tumors. This agrees with observations of others in similar intraspecific systems. These hybrids remained nontumorigenic after subcloning and prolonged culture. However, they had not lost their tumorigenic potential since tumorigenic isolates could be recovered at a low incidence either by selecting in semisolid medium or by backselecting in 6-thioguanine supplemented medium. These tumorigenic isolates had lost chromosomes, primarily those of the diploid parent, suggesting that these chromosomes convey the suppressor information. Only specific chromosomes can carry such information, since other isolates with equally low chromosome numbers were not tumorigenic. A series of cell phenotypes often found in tumorigenic cells, such as infinite life span, anchorage independence, loss of contact inhibition, decreased fibronectin production, and ability to grow at low serum concentration, were found to segregate independently of tumorigenicity, clearly indicating that they are under separate control and that they are not cell properties that by themselves, or in concert, are essential for the tumorigenic phenotype. This agrees with observations of others. However, there was some indication that these characters may potentiate tumorigenicity.

ISSN:1424-8581    

DOI:10.1159/000131494

出版商:S. Karger AG    

年代:1980

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000131495

出版商:S. Karger AG    

年代:1980

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000131496

出版商:S. Karger AG    

年代:1980

数据来源: Karger