Abstract: Compositions are administered to block IgE binding to receptors and ultimately displace native IgE from mast cells and related cell types, to prevent the activation of these cells during an allergic response. The compositions consist of a pharmaceutically acceptable carrier for systemic or local administration and an amount of compound binding specifically to the Fc&egr;RI IgE binding sites, and more preferably, Fc&egr;RI and Fc&egr;RII IgE binding sites, to prevent activation and degranulation of mast cells in response to exposure to allergens. The compounds can consist of IgE molecules and fragments and modifications thereof, such as IgE fragments, humanized or single chain IgE antibodies or fragments thereof, IgE with a modified Fab, non-crosslinkable IgE, or peptidomimetics which bind to the same site on the receptor as the IgE, jointly referred to herein as “IgE fragments” unless otherwise stated.

Abstract: It has been discovered that one can predict the likelihood a child will outgrow an allergy, especially a food allergy, by screening for IgE antibodies immunoreactivities with linear versus conformational epitopes. The child is first screened using standard techniques to determine what antigens the child is allergic to. The immunoglobulins in the sample from the patient are then characterized either using the natural purified antigen, recombinant antigen, reduced and alkylated antigen, proteolytic fragments of the antigen or synthetic peptides of between four and 40 amino acids in length, preferably six to ten amino acids, which can be immobilized for rapid and accurate screening. The antibodies from the patient, typically present in a serum or plasma sample, are reacted with the protein or peptides to determine which peptides are bound by the antibodies. These antibodies are then characterized to determine if the epitopes they bind are linear or conformational.