Depressed mediator release by inflammatory exudate cells in immunized rats following antigen challenge

The aim of the present study was to characterize leukocytes present in a local inflammatory reaction with respect to production of prostaglandin E (PGE) and the release of factors affecting lymphocyte function, which are produced by macrophages (interleukin-1) or stimulated lymphocytes (interleukin-2). Lewis rats immunized against bovine serum albumin (BSA) were challenged by intraperitoneal injection of antigen. The PGE release by peritoneal cells (PEC) was tested in vitro and found to be enhanced in immunized rats before BSA challenge. However, PEC harvested after the injection of antigen showed a marked reduction in prostaglandin production during the first 24 hr. When these cells were tested for the secretion of lymphokines (IL-1, IL-2) the same depression was found.