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A unique installation and an original investigation method are described for studying mechanoluminescence of lymphocytes. The spectral content of mechanoluminescence of lymphocytes of human peripheral blood showed maxima of optical emission at 262, 291, 335 and 412 nm. Intraperitoneal administration of hydrocortisone in mice enhances thymocyte mechanoluminescence intensity after 2 and 3 days by 33 and 62%, resp. It is shown that Acridine orange, reacting with murine thymocytes and their nucleoids, affects intensity of their mechanoluminescence, depending on the value of concentration of the injected intercalator.

The alkaline phosphatase activity was studied in embryonic lung human fibroblasts grown in vitro. The total enzyme activity per flask was constant during the log-phase of culture growth to increase significantly after confluence. The increase in the activity did not depend on the rate of culture growth, and was seen to start after the mean density equal to (37.5 +/- 5.9) X 10(3) cells/cm2 flask surface. The stimulation of cell growth may presumably slow down the synthesis of alkaline phosphatase, which resumes after the contact inhibition of DNA replication.

A new strain of the embryonic human fibroblasts L-68 was obtained and thoroughly characterized. It completely met all the requirements of the International Committee on the Cells Cultures. This strain can be recommended as a substrate for production of viral vaccines, diagnostic preparations and for research purposes.

A study was made of the relationship between the activity of alkaline phosphatase and the proliferation of cultured human cells with different replicative potentials. It is shown that alkaline phosphatase plays a role as one of endogenic stimulators of cellular proliferation. The ageing of diploid cells is accompanied by a decrease in the enzyme activity. Maximum activity was observed during a period of logarithmic cell growth. Addition of placental alkaline phosphatase to the synchronized diploid cells stimulated DNA synthesis in the S-phase of the cell cycle. Heteroploid cells with a high growth rate possessed a 30-100 times higher alkaline phosphatase activity than in the diploid cells. Under certain conditions alkaline phosphatase may presumably function as a proteinkinase.

Using the analytic microscope "Parmoquant-2" (GDR), histograms were obtained demonstrating electrophoretic mobility (EPM) of lymphoid cells of C57BL/6 mice in the course of growth of the Lewis carcinoma (3LL) and melanoma B16 administered under the skin of the femur. Changes in the average values of EPM of thymic, splenic and lymph nodal cells in the process of tumor growth appeared similar. It is shown that the medium thymocyte EMP is growing towards the terminal stage of tumor growth, at the expense of the decrease in the share of PNA+ cells. Splenic cell bimodal distribution according to EPM became, in the course of tumor growth in intact mice, unimodal with some insignificant decrease in the median EPM values. The median EPM of regional and distant lymph nodes in the process of tumor growth is of phase character. It is supposed that investigation of lymph node EPM could be used for studying tumor growth kinetics.

Kinetics of acid-insoluble non-histone protein synthesis during S and G2 cell cycle phases of diploid human fibroblasts and heteroploid transformed cells was investigated. Two distinct groups of protein with different kinetic pattern depending on the cell culture type were revealed. Export of one group of protein and turnover of the other group of acid-insoluble non-histone protein is arrested in heteroploid transformed cells.