Abstract
A method is presented which allows the quantification of the effects of chemotactic factors on polymorphonuclear leukocytes on the basis of a sensitive ATP measurement using bioluminescence. The assay measures those cells which have migrated through a commercial 3 μm filter system (Transwell™). The assay was tested under standardized conditions with different chemotactic agents (leukotriene B4 [LTB4], N‐formyl‐methionyl‐leucyl‐phenylalanine [FMLP], N‐formyl‐methionyl‐leucyl‐phenylalanine‐methyl ester [M‐FMLP]). Under appropriate conditions the migration of PMN‐cells is time‐dependent and linear for 60 minutes. Spontaneous migration of PMN cells is simultaneously quantified in a simple way, and the value obtained allows a determination of the actual chemotactic stiuation of the PMN cells. In healthy humans the spontaneous migration varied between 4.2% and 14.4% of the total number of PMN cells. An optimal chemotactic activity was detected at 10^−8^/mol/I for FMLP and 10^−7^ mol/l for M‐FMLP in PMN leukocytes, which correlates with literature values. It was also found that in contrast to EDTA blood, heparinized blood lowers the ATP level of PMN cells (by about 50%) and therefore heparinized blood is not recommended for chemotactic experiments. This assay is a simple tool for quantification of the spontaneous migration, and the chemotactic response to specific factors and their inhibitors in particular for pharmacological experiments. In contrast to the ‘classical’ chemotactic assays this method also permits the simultaneous testing of the influence of chemotactic substances on cellular ATP levels.