Macrophages do not inhibit the participation of the nuclei of nonmalignant proliferating cells in DNA synthesis in heterokaryons

Journal Article · Mon Jul 01 04:00:00 EDT 1985 · Dokl. Biol. Sci. (Engl. Transl.); (United States)

OSTI ID:5841831

Egorov, E E; Prudovskii, I A; Zelenin, A V

The authors continue their investigations into types of heterokaryons in an effort to detect an inhibition of nondividing macrophages (differentiated cells) on the entry of the nuclei of proliferating cells into replication. For the experiments described in this paper, the authors used asynchronous cultures of mouse diploid fibroblasts (MDF), 3T3 mouse cells from continuous culture, and malignant SV3T3 cells (3T3 cells transformed by SV40). Fusion of the cells of the cultures with macrophages was performed using PEG at various periods after deposition (2, 8, 12, and 20 h). The authors used double isotope marking to identify DNA synthesis in the heterokaryons. For this purpose, the nuclei of the culture cells were labeled with (/sup 3/H)thymidine before fusion with macrophages. All the nuclei of the culture cells intensively incorporated the label. After fusion, (/sup 14/C)thymidine was introduced into the incubation medium. If the cell nucleus began to synthesize DNA, it incorporated (/sup 14/C)thymidine, and a supplementary relatively weak label appeared on the auto-radiographic preparations, both above the nuclei themselves and next to them. The nuclei of macrophages in which DNA synthesis was reactivated contained only the (/sup 14/C)label. Fixation was performed 26 h after stimulation (in the case of 3T3) or 35 h after stimulation (for MDF). The percentages of nuclei of culture cells labeled with (/sup 14/C)thymidine were determined in the heterokaryons and free-lying cells.

• Research Organization: Institute of Molecular Biology, Moscow, USSR
• OSTI ID: 5841831
• Journal Information: Dokl. Biol. Sci. (Engl. Transl.); (United States), Journal Name: Dokl. Biol. Sci. (Engl. Transl.); (United States) Vol. 280:1-6; ISSN DKBSA
• Country of Publication: United States
• Language: English

Related Subjects

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59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMALS
AZINES
BIOCHEMISTRY
BIOLOGICAL EFFECTS
BIOSYNTHESIS
CARBON 14 COMPOUNDS
CELL CONSTITUENTS
CELL CULTURES
CELL NUCLEI
CELL PROLIFERATION
CHEMISTRY
CONNECTIVE TISSUE CELLS
DNA
DNA REPLICATION
DOUBLE LABELLING
FIBROBLASTS
HETEROCYCLIC COMPOUNDS
INHIBITION
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LABELLING
MACROPHAGES
MAMMALS
MICE
NUCLEIC ACID REPLICATION
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHAGOCYTES
PYRIMIDINES
RADIONUCLIDE KINETICS
RIBOSIDES
RODENTS
SOMATIC CELLS
SYNTHESIS
THYMIDINE
TRACER TECHNIQUES
TUMOR CELLS
UPTAKE
VERTEBRATES