Chemotactic stimulation by cell surface immune reactions

Abstract

CHEMOTAXIS of migratory leukocytes is of special interest to immunologists as it is intimately associated with tissue reactions initiated by immune responses. Chemotactic activity as measured in vitro with the Boyden chamber has been exclusively associated with chemotactic factors of various origins which all have in common the inherent ability to attract the responding cells. Immune-related chemotactic factors attracting neutrophils (polymorphonuclear leukocytes, PMNs) and macrophages are either complement (C)-derived as a result of C activation or they are products of activated lymphocytes. Thus, their activity is secondary to a specific humoral or cellular immune reaction taking place independent of and at a distance from the responding cell. Here we present a new concept of chemoattraction in which the chemotactic stimulus is a direct result of an immune reaction that proceeds on the surface of the responding cell itself. This concept originated from the discovery of the chemotactic stimulation of PMNs by cytotoxic sera at subcytotoxic doses.