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Natural Killer Cells

Natural killer (NK) cells were first identified for their ability to kill tumor cells without activation. NK cells are a focus of many cancer immunotherapies, as they display rapid and potent immunity to metastasis or hematological cancers.

Measuring the activity of natural killer cells is necessary for many immune applications. ATCC’s Human Primary CD56+ NK Cells provide researchers with a physiologically relevant and highly validated source of natural killer cells for cytotoxic killing activity assays. Combined with ATCC’s K-562-GFP cells, scientists can perform cytotoxicity assays with no upstream preparation in a manner which addresses the drawbacks of previous methods.

Cytotoxic Killing Activity in ATCC Natural Killer Cells

Cytotoxic Killing Activity in ATCC Natural Killer Cells

Three lots of human natural killer cells (ATCC® PCS-800-019™) were tested for cytotoxic killing activity using GFP-expressing K-562 cells in a flow cytometry-based assay. Depending on the effector:target ratio and the donor, the extent of lysis ranged from 4% to a maximum of 54%.

Natural Killer Cells

Primary CD56+ Natural Killer (NK) Cells
Natural Killer Cell Lines

ATCC offers both human primary natural killer cells and NK cell lines for the research of Cancer Immunology.


K-562-GFP Cell Line
K-562-luc2 Cell Line
K-562 Cell Line

ATCC maintains numerous cell lines which can be used as target cells for natural killer cells. These cells are useful in any experiment which seeks to observe or characterize the activity of NK cells.