Rapid micromeasurement of neutrophil exocytosis.

A simple method is described for the visual detection of neutrophil granule exocytosis. The microassay measures release of myeloperoxidase from azurophilic granules following neutrophil stimulation and can be accomplished in less than 30 min. The assay is sensitive, reproducible from day to day, and does not require separation of leukocytes from the reaction before enzyme assay. The procedure is also applicable to the rapid measurement of the suppression of degranulation by antiinflammatory agents.