[State of the art in immuno-allergology: histamine-releasing factors (HRF)]

The present concepts on histamina releasing factors are discussed, their cellular origins, their effect on the target cells and its importance in asthma immunopathology. Personal results on the production of HRF by alveolar macrophages stimulated by allergen and its action on non atopic basophils are presented. Alveolar macrophages from atopic asthmatics release HRF in presence of allergen. Macrophage from non atopic do not. HRF has been tested in a Human Basophil Degranulation Test (HBDT) preparation, a significant degranulation induced by HRF from atopic patient being only observed when atopic basofils are used in HBDT. These results confirm that allergen could induce HRF production from alveolar macrophages and that this HRF could degranulate basophils in atopic and induce mediators release.