Priming of eosinophil and neutrophil migratory responses by interleukin 3 and interleukin 5

In the present study the influence of interleukin 3 and interleukin 5 on the migration of normal eosinophil and neutrophil granulocytes has been investigated. LTB4, PAF, f-MLP, C5a and ZAS were used as chemoattractants, and HSA and pooled normal human serum were used as chemokinetic agents. Recombinant human IL-5 (rh-IL5) at a concentration of 4 x 10(-12) mol/l was chemotactic for eosinophils, while recombinant mouse IL-5 (rm-IL5) attracted both eosinophils and neutrophils. IL-3 (rh-IL3) at a concentration around 10(-12) mol/l exerted a priming effect on eosinophil and neutrophil migration, i.e. chemotactic and chemokinetic responses to all agents tested. Human IL-5 at a concentration of 2 to 20 x 10(-12) mol/l primed the chemotactic and chemokinetic responses of eosinophils to all agents tested. The migration of neutrophils was also primed by rh-IL5, but at higher concentrations, i.e. around 10(-10) mol/l. IL-5 of mouse origin primed the migration of both eosinophils and neutrophils. In conclusion, IL-3 primed the migratory function of both eosinophils and neutrophils, while IL-5 was a more potent primer of eosinophil than of neutrophil migration.