Chemokinesis and necrotaxis of human granulocytes: the important cellular organelles.

The directed and non-directed locomotion of human polymorphonuclear leukocytes on a glass surface was compared to Brownian and drift motion. The average track velocity was measured under different conditions. The track velocity of colchicine treated cells was the same as control cells. However, cytochalasin B treated cells and cytokineplasts had a reduced track velocity compared with the control cells. The non-directed locomotion was investigated by measuring the mean square displacement as a function of time. The diffusion constant, D, which quantitates the random walk process, and the characteristic time, tau, which governs the migration of the cell, was calculated. The value of the diffusion constant depended on the cell treatment: For control cells 261 micron2/min, for colchicine treated cells 145 micron2/min, for cytochalasin B treated cells 55 micron2/min, and for cytokineplasts 47 micron2/min. The characteristic time was about 40 s. The measurement showed that the nondirected locomotion can be described by the Brownian motion. The directed locomotion was investigated by a necrotactic assay and quantitated by the McCutcheon index. This index was for control cells 0.85 +/- 0.07, for colchicine treated cells 0.8 +/- 0.07, and for cytokineplasts 0.75 +/- 0.1. The measurement showed that the directed locomotion can be described by a process which is called drift mode. From this method of analysis it was determined that the important organelles of the cell for the directed and the non-directed locomotion are: (i) A part of the plasma membrane, (ii) the microfilaments, and (iii) an unstructurated part of the cytoplasme. The microtubules of the cell are only of minor importance for the directed and the non-directed locomotion.