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Biomedical subjects

R Ber

Publications and source records attributed to R Ber.

7 recordsLinked to original sources
PubMed1978

Somatic cell hybrids between human lymphoma cell lines. V. IdUrd inducibility and P3HR-1 superinfectability of Daudi/HeLa (DAD) and Daudi/P3HR-1 (DIP-1) cell lines.

We have studied two types of somatic cell hybrid with regard to expression of the Epstein-Barr virus (EBV) cycle and its regulation. The first, DIP-1, a hybrid formed between two human lymphoma EBV producers (Daudi and P3HR-1), contained EBV DNA, expressed the virus-determined nuclear antigen (EBNA), andwas a producer of the EBV-associated antigens EA (early antigen) and VCA (viral capsid antigen). The second, DAD, a hybrid series of clones formed between Daudi and a HeLa cell derivative (D98), differed with regard to the expression of EBNA, EA, VCA and the content of EBV DNA. EA was regularly induced in the EBV DNA-containing hybrids following treatment with iododeoxyuridine (IdUrd). This induction was greater in lines spontaneously expressing EA. In two hybrids, DIP-1 and DAD10, VCA and virus DNA synthesis were also induced in the presence of IdUrd, the latter being detected by in situ hybridization with P3HR-1 EBV complementary RNA. Finally, while DIP-1 was superinfectable by the P3HR-1 EBV strain, the DAD series of hybrids were refractory to P3HR-1 superinfection and lacked EBV receptors.

Antigens, Viral↗
PubMed1978

Proof of in vivo fusion of murine tumor cells with host cells by universal fusers.

Two mouse cell lines (A9HT CI.3C and 501-1), each carrying both a recessive and a dominant mutation (and therefore designated "universal fusers"), were utilized for selection of in vivo hybrids from tumors produced intraperitoneally and subcutaneously in appropriated hosts. The double selective medium eliminated both parental (tumor and host) cells but allowed the survival and proliferation of the fused product. This proved that hybridization between tumor and host cells occurred in vivo.

Animals↗