Definition

A preparation of cytokine-induced killer (CIK) cells, with potential immunopotentiating and antineoplastic activities. CIK cells are generated from peripheral blood lymphocytes (PBLs) by sequential ex vivo incubation with a monoclonal antibody against CD3 (anti-CD3), interferon-gamma (IFN-g) and interleukin-2 (IL-2), followed by expansion. CIK cells are heterogeneous cells comprising CD3+CD56- T cells, CD3-CD56+ natural killer (NK) cells, and CD3+CD56+ natural killer T (NKT) cells. Upon administration of the CIK cells into the patient, the terminally differentiated CD3- and CD56-positive subset of the CIK cells primarily exert the direct MHC-unrestricted tumor killing activity.