Inhibition of human lung mast cell sensitization by IgE in allergic sera

Passive sensitization of mast cells in human lung tissue by antigen-specificity IgE was inhibited by allergic sera containing IgE of other specificities.IgE-free sera and heat-treated sera failed to inhibit. Inhibition by purified myeloma IgE was quantitatively similar to that produced by serum IgE. It is concluded that IgE antibodies of different antigen specificity at concentrations found in allergic sera compete for cell surface receptors on human mast cells.