A simplified Boyden chamber assay for neutrophil chemotaxis based on quantitation of myeloperoxidase.

Cell locomotion and chemotaxis are usually assayed by the Boyden chamber technique, in which the response is measured by microscopical counting of the cells migrated into a micropore filter. We report a simplified Boyden chamber method which utilizes myeloperoxidase (MPO) specific to neutrophilic and monocytic leukocytes. The chamber is incubated for a period long enough for the neutrophils to migrate through the first of two superimposed filters. The cells entering the second filter are then lysed and the released MPO activity is quantitated. Random migration, chemokinesis, and chemotaxis measurements of neutrophils were compared by the enzymatic and the conventional cell count methods. There was good agreement between the two methods (0.84 less than r less than 0.98). The intraassay precision of the enzymatic and the cell count methods was equal; the coefficients of variation were 14 and 15%, respectively. The enzymatic method provides a more objective, reliable, and rapid modification of the Boyden chamber assay for analysis of neutrophil chemotaxis.