Spin filter culture: the propagation of mammalian cells in suspension.

A spin filter device has been used for the propagation in vitro of cells of mnouse leukemia L1210 to densities approaching 10(8) cells per milliliter. By manipulation of flow rates, cells may be exposed to exponentially declining, drug concentrations with half-times of 1.5 hours or less, providing a more realistic parallel to in vivo drug treatment than is obtained by other culture methods.