Rapid quantitative assessment of phagocytic activity of Indium-111 labeled leukocytes by chemiluminescence

Indium-111 labeled leukocyte imaging is gaining widespread acceptance. A rapid method for assaying changes in leukocyte viability and phagocytic function during the labeling process would facilitate the evaluation of new labeling techniques and testing of labeled cells before pt injection. The authors have conducted preliminary investigations of chemiluminescence in the clinical evaluation of leukocyte labeling. The chemiluminescence assay may be performed in 30 minutes with only 0.1 ml of whole blood. Zymossan is rapidly introduced to the blood or cell suspension resulting in the emission of light which is then counted by photometer. The amount of light given off by the reaction reflects both the phagocytic function of the cells and the ability of activated phagocytes to generate activated oxygen species. They have evaluated the chemiluminescent activity of normal human leukocyte suspensions both before and after labeling with Indium-111 oxine. The chemiluminescence assay provides a rapid means of evaluating granulocyte function. Correlations of this activity with image quality may provides clues for optimization of labeling techniques