Rapid method for purification of CD56+ natural killer cells with preferential enrichment of the CD56bright+ subset

A rapid method for the purification of CD56+ natural killer (NK) cells with the preferential enrichment of the CD56bright+ subset is described. The method is based on the adsorption of CD56+ cells indirectly stained with a biotinylated antibody on an avidin-coated column. The adsorbed CD56+ cells can then be squeezed out mechanically without damaging the viability or the function of the cells. Starting from peripheral mononuclear cells from adult donors, the recovery of the CD56+ cells was 11.9 +/- 9.0% (n = 8), the purity 93.0 +/- 4.9% (n = 10), and the enrichment factor 7.5 +/- 1.7 (n = 8). Further phenotypic classification of the CD56+ cells into CD56dim+ and CD56bright+ cells showed a preferential enrichment of the CD56bright+ phenotype with a recovery of 40.5 +/- 19.6% (n = 8), a purity of 30.3 +/- 13.2% (n = 8), and an enrichment factor of 29.8 +/- 7.2 (n = 8). In conclusion, the described method allows the rapid purification of CD56+ NK cells with the preferential enrichment of the CD56bright+ subset.