Chemotaxis of eosinophils and neutrophils by aggregated immunoglobulins

Abstract

Human myeloma proteins of all recognized immunoglobulin classes, including IgE, were purified and chemically aggregated. The chemotactic properties of these aggregated immunoglobulins for enriched preparations of human eosinophils and neutrophils were studied in vitro with the use of a modification of the Boyden chamber. Significant chemotactic effects were exerted on eosinophils and neutrophils by IgG and IgM in the presence of fresh human serum. IgE did not attract eosinophils either alone or in the presence of fresh serum. Inhibition of chemotaxis was observed when fresh human serum was heated at 56 °C. for 30 minutes and when the same concentration of chemotactic agents was placed in both compartments of the chambers. The results indicate that aggregated IgG and IgM, in the presence of fresh human serum, generate chemotactic factor(s) for eosinophils and neutrophils and that heatlabile serum factors are essential for chemotaxis of these cells. These results are discussed in terms of the eosinophil and neutrophil chemotactic factors derived from the complement system, ECF-C and NCF-C, and the eosinophil chemotactic factor of anaphylaxis, ECF-A, associated with immediate-type hypersensitivity reactions.