title: The effect of immunity to core lipopolysaccharides (LPS) on the production of thromboxane and prostacyclin by equine peritoneal macrophages.
abstract: An experiment was designed to determine whether a change in the ability of macrophages to respond to lipopolysaccharides (LPS) of gram-negative bacteria was involved in the development of cross-reactive immunity to endotoxemia. The endotoxin-induced production of thromboxane A2(TxA2) and prostacyclin (PGI2) by peritoneal macrophages from horses which were hyperimmunized against the common core region of LPS were compared to those in unimmunized horses. Bacterins used for induction of core LPS immunity were prepared from the J-5 mutant of Escherichia coli 0111:B4, and the R 595 mutant of Salmonella minnesota. Serum antibody titers to core LPS were determined by an indirect enzyme-linked immunosorbent assay. Immunized horses had a marked increase in titer to core LPS (p less than 0.05), while there was no change in titer in unimmunized control horses. The only significant difference in the in vitro LPS-induced production of TxA2 and PGI2 by peritoneal macrophages between immunized and control horses was a greater production of TxA2 by macrophages from immunized horses in response to 10 ng/ml LPS (p less than 0.05). Results of this experiment do not support the concept that cross-reactive immunity to LPS is attended by reduced production of TxA2 and PGI2 by equine peritoneal macrophages.
authors.affiliation: Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602.
authors.forename: D D
authors.initials: DD
authors.lastname: Morris
authors.forename: J N
authors.initials: JN
authors.lastname: Moore
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D003429:Cross Reactions; D004731:Endotoxins / Q000097:blood*; D011464:Epoprostenol / Q000096:biosynthesis*; D004926:Escherichia coli; D006736:Horses; D007074:Immunoglobulin G / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D012475:Salmonella; D013928:Thromboxane A2 / Q000096:biosynthesis*
chemical_list: D000907:Antibodies, Bacterial; D004731:Endotoxins; D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D013928:Thromboxane A2; D011464:Epoprostenol