The IgE-Mediated Release of an Eosinophil Leukocyte Chemotactic Factor from Human Lung

Abstract

Summary: Following antigenic challenge of human lung passively sensitized with serum from a ragweed-sensitive donor, the anaphylactic diffusate contained, in addition to histamine and slow reacting substance of anaphylaxis (SRS-A), a factor selectively chemotactic for human eosinophils (ECF-A). ECF-A evoked the migration of eosinophils obtained from the blood of a number of donors with eosinophilia. ECF-A was distinguished from histamine, bradykinin, serotonin, the prostaglandins PGE1, PGE2 and PGF2α and from SRS-A. The immunoglobulin mediating the release of ECF-A was IgE. Heating or absorption of ragweed-sensitive serum with a rabbit antibody specific for IgE removed its ability to passively sensitize lung for mediator release, and anti-IgE released ECF-A from normal lung. ECF-A, a unique mediator of the anaphylactic reaction, has been identified in human lung tissue.