Purification of morphologically and functionally intact human basophils to near homogeneity

Certain studies on basophils require highly purified functionally intact cell preparations. Here, a three-step procedure is described that meets these requirements. The procedure consists of a Ficoll density gradient step, counterflow elutriation and negative selection by magnetic cell sorting (MACS). The mean purity of basophils obtained from 30 donors was 97.6 +/- 3.96% with a viability of 99.6 +/- 0.83%. The recovery rate was 49.7 +/- 15.6%. The cells had a normal morphological appearance as assessed by May-Grunwald-stained cytospins and were functionally intact as shown by their unaltered capacity to release histamine and interleukin 4 (IL-4) following immunological activation. This procedure is a clear improvement over currently available techniques and should facilitate future investigations on basophils. (C) 1999 Elsevier Science B.V. All rights reserved.