Isolation and immunochemical properties of mouse IgE

Abstract

Through physical, chemical and immunochemical techniques, a greater than 450-fold purification of mouse reagin was achieved from reaginic ascitic fluid. Antiserum to this reagin pool, appropriatealy absorbed with normal mouse serum, mouse gamma globulin, and mouse Fab, specifically reacted with mouse IgE since it abolished the 48-hr but not the 2-hr passive cutaneous anaphylaxis reaction of reaginic serum. this antiserum also precipitated a component in the reagin pool which was immunochemically distinct from any known class of mouse immunoglobulins, but was immunoglobulin in nature because it reacted with rabbit antiserum to mouse Fab. This precipitin was partially identical to rat IgE myeloma protein, and had an electrophoretic mobility similar to it was detected in normal or reaginic mouse serum or reaginic ascitic fluid, but not in serum isolated from SJL/J mice, a strain that is a poor producer of reaginic antibody. Through use of a specific immunoadsorbent, the component was isolated from normal mouse serum and was shown to be identical to that from reaginic ascitic fluid. Based on these studies, it was concluded that this precipitin was mouse IgE.