COMPARISON OF TECHNIQUES FOR THE ASSESSMENT OF POLYMORPHONUCLEAR LEUKOCYTE POLARIZATION IN SUSPENSION

Polarisation of polymorphonuclear leukocytes (PMN) in suspension was a ssessed using three techniques: 1) visual classification; 2) computeri sed morphometry; and 3) flow cytometry. While visual classification de tected the formation, polarisation and type of cytoplasmic extensions produced by PMN, morphometry and flow cytometry detected only the form ation of extensions. The area, perimeter and ellipticity were, in gene ral, statistically different for each subtype of PMN-shape identified by visual classification. Furthermore, the magnitude and direction of changes detected by flow cytometry were affected by the use of erythro cyte lysis (during isolation of the cells) and the fixative used prior to analysis. The findings of this study demonstrate that visual class ification is a more sensitive, reliable and appropriate assay of PMN p olarisation than current morphometric and flow cytometric methods.