title: Ex vivo generation of highly purified and activated natural killer cells from human peripheral blood.
abstract: Adoptive immunotherapy using natural killer (NK) cells has been a promising treatment for intractable malignancies; however, there remain a number of difficulties with respect to the shortage and limited anticancer potency of the effector cells. We here established a simple feeder-free method to generate purified (>90%) and highly activated NK cells from human peripheral blood-derived mononuclear cells (PBMCs). Among the several parameters, we found that CD3 depletion, high-dose interleukin (IL)-2, and use of a specific culture medium were sufficient to obtain highly purified, expanded (∼200-fold) and activated CD3(-)/CD56(+) NK cells from PBMCs, which we designated zenithal-NK (Z-NK) cells. Almost all Z-NK cells expressed the lymphocyte-activated marker CD69 and showed dramatically high expression of activation receptors (i.e., NKG2D), interferon-γ, perforin, and granzyme B. Importantly, only 2 hours of reaction at an effector/target ratio of 1:1 was sufficient to kill almost all K562 cells, and the antitumor activity was also replicated in tumor-bearing mice in vivo. Cytolysis was specific for various tumor cells, but not for normal cells, irrespective of MHC class I expression. These findings strongly indicate that Z-NK cells are purified, expanded, and near-fully activated human NK cells and warrant further investigation in a clinical setting.
authors.affiliation: Department of Frontier Surgery, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Saito
authors.forename: Yui
authors.initials: Y
authors.lastname: Harada
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Morodomi
authors.forename: Mitsuho
authors.initials: M
authors.lastname: Onimaru
authors.forename: Kumi
authors.initials: K
authors.lastname: Yoshida
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Kyuragi
authors.forename: Hisahiro
authors.initials: H
authors.lastname: Matsubara
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Yonemitsu
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D020014:K562 Cells; D015979:Killer Cells, Lymphokine-Activated / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism; D051379:Mice; D016688:Mice, Inbred NOD; D023041:Xenograft Model Antitumor Assays; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D007371:Interferon-gamma; D037181:Lectins, C-Type; D000099192:CD69 Antigens