New method for the measurement of eosinophil migration.

A new application of the Boyden chamber method for the measurement of eosinophil migration, without the need of eosinophil isolation, has been developed. A cell suspension containing a mixture of granulocytes, neutrophils to the greater part, was used. The eosinophils were identified by staining their granules with Chromotrope 2R. The method made it possible to study the migration of eosinophils from normal individuals without eosinophilia. Control experiments demonstrated that the chemotactic and chemokinetic response of eosinophils in the granulocyte mixture was in accordance with the response of isolated eosinophils from the same donor. Normal eosinophils demonstrated a significant chemotactic response to C5f, platelet-activating factor (PAF), leukotriene B4 (LTB4), and f-meth-leu-phe (f-MLP). Furthermore, PAF was demonstrated to be significantly more eosinophil chemotactic than neutrophil chemotactic.