Normal chemotactic activity of granulocytes obtained by filtration leucapheresis.

The chemotactic activity of granulocytes obtained by the Terumo Filtration Leucapheresis System (F.L.) was examined by the method of Boyden's chamber. The number of cells migrating through the Millipore filter was expressed as the chemotactic activity. The mean values were 117 for the F.L. and 122 in a control, in which cells were collected from the same donor blood using dextran sedimentation. The results suggested that the in vitro chemotactic function of granulocytes obtained by F.L. was within normal limits.