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Biomedical subjects

L Weiss

Publications and source records attributed to L Weiss.

At least 685 records · Page 38Linked to original sources

Studies on cell deformability. 3. Some effects of EDTA on sarcoma 37 cells.

The nonlethal procedure of incubation in EDTA solution makes the peripheral regions of ascites sarcoma 37 cells more easily deformable, as reflected in measurements of the decreased amount of negative pressure required to suck out standard hemispherical bulges from the cells into micropipettes. The facilitation of deformability was abolished after reincubation of cells in calcium-containing saline, and this mechanical parameter was partially restored to normal after reincubation in magnesium-containing saline; the mechanical effect of EDTA treatment is, therefore, thought to be due mainly to the removal of calcium from the cell periphery. As EDTA treatment produces no detectable change in cellular electrophoretic mobility, it is concluded that peripheral calcium must be bound to anionic sites deeper than about 10 A from the cellular hydrodynamic slip plane. The data are discussed with emphasis on the view that they should not be extrapolated freely to other cell types.

Animals↗

Studies of cell deformability. IV. A possible role of calcium in cell contact phenomena.

Cells grown in suspension culture were incubated with EDTA-disodium salt and shown to have more easily deformable surfaces and raised electrophoretic mobility than controls, following this treatment. The reversibility of these observations by the addition of calcium ions, and other parallel experiments, support the conclusion that, in these cells, calcium is bound to anionic sites at the cell periphery, some of which are located at the cellular electrokinetic surface. These cells should, therefore, exhibit demonstrable calcium-sensitive aggregation, if current theories on the role of calcium in the physiological situation are correct. The fact that no calcium-sensitive aggregation was observed suggests that calcium does not form "bridges" between the adjacent anionic sites on different cells, and does not act directly by its effects on the diffuse electrical double-layer in this situation. An alternative hypothesis is advanced for the role played by calcium in cell adhesion and separation processes.

Calcium↗