Recently, we have begun to image neutrophils loaded with calcium sensitive dyes (i.e. Fluo-4). Using this method, we have determined that calcium influx is closely linked to the deceleration of rolling neutrophils to an arrest. Furthermore, we have found that the process of rolling on a selectin bearing surface increases the base-line calcium concentration. Simultaneous measurements of neutrophil rolling velocity and calcium concentration would clearly not be possible with a static imaging technique.
LFA-1 localization and distribution on PMN crawling on recombinant ICAM-1 and E-selectin
PMN labeled with Fluo-5f Calcium dye. Real time calcium imaging at contact sites of PMN arresting on ICAM-1 and E-selectin susbtrate by TIRF
fMLP triggered neutrophil arrest and calcium flux on endothelial cell monolayer
High affinity CD18 in unactivated neutrophils on recombinant ICAM-1 substrate