Lymphocyte locomotion. I. The initiation, velocity, pattern, and path of locomotion in vitro.

The locomotive behaviour of human lymphocytes in coverslip preparations of clotted autoplasma was studied at +37 degrees C. Lymphocytes isolated from peripheral blood or from the tonsils did not move prior to membrane activation by means of incubation with phytohemagglutinin (PHA). After PHA stimulation the locomotion of 19 lymphocytes was analysed by time-lapse fliming. The locomotion was random, as evidenced by a median locomotive index of 0.64 (Q1-Q3 0.04-0.75) and comparatively slow, median velocity 15 mum/min (Q1-Q3 12-18). The locomotion of 5 other lymphocytes was studied at high magnification. It is suggested that the characteristic polarity of wandering lymphocytes, indicating the direction of movement, can be utilized in the analysis of the lymphocyte traffic in tissue sections of post-capillary high-endothelium venules.