In an ordinary method, anchorage-dependent animal cells cultivated on a solid culture substrate, such as the surface of shale or micro-beads. This treatment may have detrimental effects such as the proteolysis of the cell membrane proteins. To avoid these effects, cell cultivation using a liquid-liquid interface system was used in the present study. The cells grow at the interface between a culture medium and a hydrophobic liquid. The animal cells cultivating at the interface spread less than the case of solid surface but the system Could have in situ conditions. In the present study, the following results were obtained :
(1) Quantity and kind of the surface active agent affected to the adhesion of the cells at the interface.
(2) Morphology of the cell was controlled by concentration of surface active agent which varied cell adhesion to the interface.
(3) Cell spreading at the interfaces was relatively small, so that the cells at an interface anchored. with one another and formed multicel
lular hemispherical aggregations shaped like a spheroid.
(4) Cultivation on the emulsion surface was also tried, as a result, it was found that the diameter distribution of the emulsion should be uniform for the purpose of recovery of the cells and preventing the coalescence of each other^<**>.
(5) Using emulsion with the systems of oil-in water and water-in-oil, cultivation efficiency was exceeded than the case of using flat plate in both cases.
^<**>Sato, M., Hishinuma, T., Terachi, K., Hatori, T and Saito, M. : "Electrostatic mono dispersion of insulating and viscous liquid in distillled water, "Electrostatics'95 (9th International Conference), P1.21, pp.65-66 (York, 1995) ; Sato, M., Hatori, T.and Saito, M. : "Experimental investigation of droplet formation mechanisms by electrostatic dispersion in a liquid-liquid system, "Conf.Rec.-IAS Annu.Meet (IEEE), pp.1485-1492 (Orlando, 1995) ; Sato, M., Kato, S.and Saito, M. : "Production of O/W type uniformly sized droplets using AC convergent eletric field, "IEEE Trans. Ind.Appl., 32,138-145 (1996) ; Sato, M., Kudo, N., and Saito, M., "Surface tension reduction of liquid by applied electric field using vibrating jet method, "Conf.Rec.-IAS Annu.Meet. (IEEE), pp.1762-1767 (San Diego, October, 1996) Less