Purification of human CD41a⁺ cells.

An enriched population of MKs was isolated after labeling with anti–CD41a-FITC antibody and anti-FITC immunomagnetic microbeads in the presence of 2 inhibitors of MK activation, adenosine and theophylline. The cells were analyzed by flow cytometry after having been passed once (single pure) and twice (double pure) through a magnetic column. This technique resulted in the isolation of a 98% pure CD41a⁺ MK population.