The release of histamine from human leukocytes is a useful in vitro model for studying allergic disease1. Many of the drugs used in the treatment of allergy and asthma (for example, isoprenaline and theophylline) are effective inhibitors of in vitro histamine release2. However, the anti-inflammatory steroids have not been found to inhibit the in vitro release of histamine from mast cells or basophils activated by immunological stimuli3-6. In view of the fact that the in vivo anti-allergic effects of steroids occur only 12-24 h after administration7, we have re-examined the effects of these drugs on IgE-mediated histamine release from human basophils after prolonged incubations. We report here a time-dependent inhibition of histamine release from human basophils by glucocortico-steroids. The relative activity of a series of steroids as inhibitors of histamine release correlates well with the relative in vivo anti-inflammatory activity of the same compounds. These results suggest that the basophil may be an in vivo target of the anti-inflammatory steroids and that inhibition of this cell type may account for some of the activity of steroids in preventing inflammation.
ASJC Scopus subject areas