RELATIONSHIP BETWEEN LIGHT-SCATTERING IN FLOW-CYTOMETRY AND CHANGES IN SHAPE, VOLUME, AND ACTIN POLYMERIZATION IN HUMAN POLYMORPHONUCLEAR LEUKOCYTES

Using two different cytometers, an Epics Profile II and a FACScan, we determined the extent to which changes in forward and right angle scat ter are a reliable measure for changes in polymorphonuclear leukocyte (PMN) shape, volume, and actin polymerization and whether distinct typ es of shape changes in PMNs can be recognized, PMN stimulation can sub stantially change the positions of PMNs in the scatter diagram of the FACScan but not of the Epics Profile II. Within the limits of the expe riments, it has been possible to determine whether or not a shape chan ge has taken place using the FACScan but not using the Epics Profile I I. However, using either cytometer, it has not been possible to determ ine which type of shape change (e.g., spherical vs, polarized vs, nonp olar cells) has taken place, Furthermore, forward or right angle scatt er changes are not a reliable measure for changes in cell volume or ac tin polymerization of human PMNs.