Neutrophil degranulation detected by right angle light scattering: spectroscopic methods suitable for simultaneous analyses of degranulation or shape change, elastase release, and cell aggregation

We have used simultaneous spectrometric analysis of right angle scattering and elastase release from human neutrophils to demonstrate the similarity of these two measures of degranulation. Both responses depend on the presence of cytochalasin B, and are similar in kinetics, dose-response, and dependence on receptor occupancy at the formyl peptide receptor. This scattering response is shown to be largely independent of cell aggregation. In the absence of cytochalasin B, a rapid and transient right angle scatter response of a different character, probably associated with cell ruffling, is detected. Either right angle response can be detected by flow cytometry.