Isolation of human eosinophils: microbead method has no impact on IL-5 sustained viability

Please cite this paper as: Isolation of human eosinophils: microbead method has no impact on IL‐5 sustained viability. Experimental Dermatology 2009; 19: 467–469. Background/purpose: In a recent issue of Experimental Dermatology (18, 2009, 654), Schefzyk et al. concluded that multi‐antibody eosinophil isolation (Miltenyi) should be abandoned, as differential purity was minimal, and eosinophils underwent accelerated apoptosis when compared with those isolated with traditional anti‐CD16 microbeads. Our intent was to investigate the universality of these findings. Methods: We isolated eosinophils from normal donor granulocyte packs using two methods, and evaluated purity, viability and annexin‐V/propidium‐iodide staining. Results: Purity was substantially greater when multi‐antibody isolation was used for eosinophil isolation from granulocyte packs (98% vs 69%). No differential survival was detected when eosinophils were maintained in culture with or without interleukin‐5. Conclusions: Multi‐antibody eosinophil isolation represents a substantial advantage over anti‐CD‐16 microbeads when isolating large numbers of eosinophils from concentrated leucocyte preparations. No differential survival was observed. While appropriate consideration of methods is always crucial, multi‐antibody eosinophil isolation should not be abandoned completely.