[Comparison of methods of detection of bovine adenovirus serotype 3 in infected culture of calf kidney cells (MDBK)].

The comparative study of the dynamics of the main antigen (hexon) and viral DNA of the bovine adenovirus type 3 accumulation in the established cell line MDBK under the conditions of single- or multistep cycle of infection has been undertaken. The quantitative immunoelectrophoresis and immunoenzyme assay detected the viral antigens on the late stages of infection in the period of cellular monolayer degradation. The immunofluorescence reaction and histochemical immunoenzyme method detected the antigen in the infected cells concurrently with the primary expression of the viral cytopathic effect.

[Reduced malignancy of hybrids of tumor cells fused with lymph node lymphocytes of syngeneic rats].

Seven cloned hybrid cell lines were obtained by fusion of OAV2a GFRT cells with lymphocytes of syngeneic rats. Three of the cell lines showed a reduced malignity when injected subcutaneously and were incapable of infiltrative growth when injected intraperitoneally. They were partially or totally devoid of colony forming activity in soft agar.

[Transforming and oncogenic properties of the adenovirus genome].

Analysis of data on transforming and oncogenic properties of adenovirus genome has shown that oncogenic properties of the cells transformed by adenoviruses are not determined by the length (to a definite extent) and by the number of copies of integrating parts of the viral DNA molecules. There are numerous sites of virus genome integration into the genome of the cell. The E1 region of the viral genome (0 to 11% of the map unit) consists of two transcription units E1a and E1b and plays the leading role in the tumourigenicity of transformed cells.

[Comparative study of sialyltransferases in cultured cells of the rat embryo, transformed by DNA bovine adenovirus type 3].

The specific activities of membrane-bound sialyl transferases from six cultures of cells transformed by bovine adenovirus DNA type 3 (BA-3) before and after passage through host animal organism were compared. The sialyl transferase activity was increased with respect to the high molecular weight acceptor, asialylofetuin in the majority of transformed and tumour cultures. Identification of sialylation products by paper chromatography revealed that all cell cultures contain sialyltransferases synthesizing neuraminosyl-alpha (2----6)N-acetyllactosamine.