[A comparative study of the ectophosphatase activity in different subpopulations of tumor cells]. / Sravnitel'noe izuchenie aktivnosti éktofosfataz u opukholevykh razlichnykh subpopuliatsii.

Activities of ectophosphatases (alkaline phosphatase, 5'-nucleotidase and ecto-ATPase) from different subpopulation of lymphoma NKLy and ovary tumor of rats were investigated. A strong positive correlation has been shown between these activities in different subpopulations. A negative correlation between proliferative activity and activities of ectophosphatases was determined. The role of ectophosphatases in cell proliferation is discussed.

[Osmotic homeostasis and radiosensitivity of NKLy lymphosarcoma cells]. / Osmoticheskii gomeostaz i radiochuvstvitel'nost' kletok limfosarkomy NKLy.

In experiments with cells of ascites NKLy lymphoma differing in ploidy and position in the cell cycle, a study was made of the radiosensitivity, osmotic homeostasis peculiarities and thermoradiation changes in potassium content. It was shown that the resistance of osmotic homeostasis of NKLy cells to thermoradiation correlated with their radioresistance and was maximally displayed in cells at the stage of DNA synthesis.

[The surface charge of NKLy ascitic tumor cells differing in their proliferative activity, in their place in the cell cycle and in their ploidy]. / Poverkhnostnyi zariad kletok astsitnoi opukholi NKLy, razlichaiushchikhsia proliferativnoi aktivnost'iu, polozheniem v kletochnom tsikle i ploidnost'iu.

The NKLy ascitic tumor cells in the stationary phase of growth were fractionated by velocity sedimentation method. Cells from the obtained fractions were characterized by measurements of DNA contents and 3H-thymidine incorporation. The surface properties of the cells from five fractions, differing in proliferative capacity, stage of the cell cycle and ploidy were considered using cell electrophoresis, two polymer aqueous phase system and Alcian blue sorption. A correlation between electrophoretic mobility and cell partition constant for these fractions has been obtained. No correlation was found between these parameters and dye absorption. The surface charge of the cells from G0/G1 and S fractions was higher than that of other cells. The polyploid NKLy cells demonstrated a lower surface charge. The surface properties of the tumor cells differing in proliferative capacity, stage of the cell cycle and ploidy are discussed.

[Effect of irradiation on the cellular sensitivity of separate NKLy tumor subpopulations to the membrane-toxic action of natural killers]. / Vliianie oblucheniia na chuvstvitel'nost' kletok iz otdel'nykh subpopuliatsii opukholi NKLy k membranotoksicheskomu deistviiu estestvennykh killerov.

A study was made of sensitivity of NKLy tumor fractions, differing in the proliferative activity, position in the cell cycle, and ploidy, to membrane-toxic action of natural killer cells from mouse spleen. The membrane toxicity index for cells of three out of five fractions under study was shown to decrease after exposure to 4 Gy radiation. It is concluded that there is no correlation between NKLy cell sensitivity to membrane-toxic effect of natural killer cells and their radiosensitivity as well as their ability to repair potentially lethal damages.

[Effect of x-rays on the sensitivity of cells of the murine NKLy tumor to the membrane toxic effect of natural killers]. / Vliianie rentgenovskogo izlucheniia na chuvstvitel'nost' kletok opukholi NKLy myshei k membranotoksicheskomu deistviiu estestvennykh killerov.

A study of membrane toxicity of allogenic splenocytes with regard to irradiated mouse NKLy lymphosarcoma cells (tested by the release of 3H-uridine label from target cells in the presence of exogenous RNAses) has displayed an insignificant increase, as compared with the control, in the membrane toxicity with radiation doses of 1-2 Gy and its decrease at higher doses.

[Clonogenic capacity, radiosensitivity and recovery from potentially lethal damage in individual subpopulations of the murine NKLy ascitic tumor]. / Klonogennaia sposobnost', radiochuvstvitel'nost' i voostanovlenie ot potentsial'no letal'nykh povrezhdenii otdel'nykh subpopuliatsii astsitnoi opukholi NKLy myshei.

Effectiveness of the diffusion chamber cloning of subpopulations of cells isolated by the sedimentation method from intact and exposed (5 Gy) mouse tumors NKLy was determined. It was shown that cells at the G2-M stages were highly radiosensitive. The recovery from potentially lethal damages was maximum at the G0-G1 stages of the cell cycle.