Primary human CD56+ cells were isolated from peripheral blood (PB) mononuclear cells (MNCs) using positive immunomagnetic separation techniques. PB was collected using acid-citrate-dextrose solution A (ACDA) as the anticoagulant. CD56 antigen is expressed primarily on natural killer (NK) cells, as well as NKT cells in PB.Cells were obtained using Institutional Review Board (IRB)-approved consent forms and protocols.Certain products are only available in select territories. Please contact your local Sales representative or Product & Scientific Support at techsupport@stemcell.com for further information.Browse our Frequently Asked Questions (FAQs) (https://www.stemcell.com/primary-cells-faq) on Primary Cells.NOTE: This product was formerly named "Human Peripheral Blood CD56+ NK Cells, Frozen"; the product itself and manufacturing procedures have not changed, but the name has been updated to more accurately reflect the cell type provided.