Ex vivo expansion of natural killer cells from human peripheral blood mononuclear cells co-stimulated with anti-CD3 and anti-CD52 monoclonal antibodies.

Background Aims: This study developed a new method to expand CD3(-)CD56(+) natural killer (NK) cells from human peripheral blood mononuclear cells (PBMCs) without feeder cells for clinical trials.

Methods: PBMCs from healthy subjects were co-stimulated with anti-CD3 and anti-CD52 monoclonal antibodies and cultured for 14 days in newly developed NKGM-1 medium containing autologous plasma and interleukin-2. Expanded NK cells were examined for cell number, phenotype, in vitro and in vivo cytotoxicity and interferon (IFN)-γ secretion.