Flow-cytometric analysis of human basophil degranulation. I. Quantification of human basophils and their degranulation by flow-cytometry.

Quantification of human basophils and their degranulation were performed using a flow-cytometric system. It was shown that the number of basophils among total leukocytes, before and after the effect of degranulating agents, can be obtained rapidly and reproducibly, following alcian blue staining. Dose-response curves of degranulation by anti-IgE and anti-IgG4 were studied, and it was shown that these antibodies can induce basophil degranulation in a Ca++ dependent manner. It was also shown that degranulation is completed within 10 min. Values obtained by flow-cytometry and microscopic evaluation, as well as comparison made between percent basophil degranulation and percent histamine release, agreed well with each other in our system. Flow-cytometric analysis of human basophil degranulation provides a new reliable method to assess in vitro the morphological basis of immediate hypersensitivity.