The separation of human palatine tonsillar cells in the reorienting gradient zonal rotor: a large-capacity enrichment of plasma cells.

Velocity sedimentation by centrifugation in a previously described isokinetic gradient, at unit gravity, or with an elutriator has proved to be highly effective as a method for the enrichment of many kinds of cells. For many biochemical and immunological purposes, the available techniques for the separation of cells have been incapable of separating a sufficient number of cells. With a newly designed rotor, we have separated more than twenty-fold more human tonsillar cells that can be separated in the previously described isokinetic gradient. Without exceeding the band capacity, we separated 692 million tonsillar cells. Plasma cells were more than seven-fold enriched from human tonsillar cells. When 692 million tonsillar cells were separated in the rotor, the five most enriched, contiguous fractions of plasma cells contained 44 million cells. The most enriched fraction contained 27% plasma cells. We are not aware of any method for velocity sedimentation which will separate such large numbers of tonsillar cells.