Separation of lipase-positive cells from suspensions of pancreas cells in an isokinetic gradient of Ficoll in tissue culture medium.

Lipase-positive cells were separated from suspensions of pancreas cells both by velocity sedimentation and by isopycnic sedimentation. Lipase-positive cells were 51.0 +/- 9.6% of the disaggregated pancreas cells in the starting sample suspension. The purest gradient fractions from experiments using velocity sedimentation for cell separation contained a mean of 98.8 +/- 0.6% lipase-positive cells. Cell separation using isopycnic centrifugation was less effective than cell separation using velocity sedimentation and resulted in a mean purity of only 89.8 +/- 6.8% lipase-positive cells. Lipase positivity was assessed using the Gomori technic with the conditions for fixation slightly modified to be suitable for disaggregated cells.