Granulocytes (the red, white, and blue) in hypersensitivity reactions: A review

This review is an attempt to summarize studies which demonstrate the participation of all three kinds of granulocytes in reactions of both immediate and delayed hypersensitivity. The focus is on the biologic control of these cell types by various mediator substances, in particular the lymphokines and the complement-derived factors. These factors collectively mobilize, attract, activate, immobilize, and otherwise affect granulocyte function in vitro and in vivo. These mechanisms which lead to control of the distribution and properties of the granulocytes are of prime importance in the production of an inflammatory reaction following an underlying immunologic event. This interface between inflammation and immunity underlies all of clinical and experimental hypersensitivity.