Comparative toxicity of the horse eosinophil peroxidase-H2O2-halide system and granule basic proteins.

摘要: Stimulated eosinophils release cytotoxic granule constituents, including eosinophil peroxidase (EPO) and a group of basic proteins (GBP). EPO reacts with H2O2 formed by the respiratory burst halide to form oxidants. The relative potency EPO-H2O2-halide system GBP is considered here. Horse were induced degranulate, degranulation products separated chromatography on Sephadex G-50 comparable volumes column fractions tested for toxicity Escherichia coli schistosomula Schistosoma mansoni in presence absence halides. Both toxic. However, peak fraction could be diluted 1000-fold at pH 7.0 5000-fold 5.0, 10-fold dilution incubation time reduced 5 s, retention bactericidal activity halides, whereas had small effect 1 h which increased prolongation 24 h. A less than log fall E. viable cell count was produced under all conditions as compared total destruction (greater fall) system. schistosomulocidal observed 2 dilution. In contrast, no 18 fractions. 5- or 50-fold increase concentration maximum between two major protein peaks. Thus, employed, contributed considerably greater degree toxic components did GBP.