Abstract: | Purified allergenic constituents from Dermatophagoides farinae mite (Df 11 and Df 6) and from orchard grass (Dactylis glomerata) pollen (F 34) are able to trigger, in the absence of IgE and IgG antibodies, human adherent cells, leading to the secretion of interleukin 1, (IL 1). This secretion was observed with adherent peripheral blood mononuclear cells from normal donors as well as from atopic patients. The IL 1 activity was evaluated by the mice thymocyte mitogenesis in the presence of suboptimal doses of Con A. The secretion of IL 1 by adherent cells was not affected by a cytotoxic treatment with OKT3 monoclonal antibody in the presence of complement, implying a direct action of allergenic fractions, on monocytes, and not through a T-cell pathway. The challenge of human monocytes with allergens in the presence of indomethacin led to culture supernatants for which a higher 3H-thymidine incorporation by mice thymocytes was detected; thus, purified allergens could also trigger the secretion of prostaglandins by human monocytes. |