Repeated infusions of donor-derived cytokine-induced killer cells in patients relapsing after allogeneic stem cell transplantation: a phase I study.

BACKGROUND AND OBJECTIVES: Cytokine-induced killer (CIK) cells have shown anti-leukemic activity and little graft-versus-host disease (GVHD) in several animal models. The safety of these cells in autologous settings has been shown. We performed a phase I study of allogeneic (donor's) CIK cells in patients relapsing after allogeneic haematopoietic stem cell transplantation (HSCT). DESIGN AND METHODS: Eleven patients with acute myelogenous leukemia (n=4), Hodgkin's disease (n=3), chronic myelomonocytic leukemia, (n=1), pre-B acute lymphoblastic leukemia (n=1) and myelodysplasia (n=2), all of whom had relapsed after sibling (n=6) or matched unrelated donor (n=5) HSCT, entered this study. RESULTS: Before CIK administration, six patients had received other salvage treatments including chemotherapy (n=5), radiotherapy (n=1) and unmanipulated donor lymphocytes (n=6) without any significant tumor response. The median number of CIK infusions was two (range 1-7) and the median number of total CIK cells was 12.4x106/kg (range 7.2-87.4). The infusions were well tolerated and no acute or late infusion-related reactions were recorded. Acute GVHD (grade I and II) was observed in four patients, 30 days after the last CIK infusion, and progressed into extensive chronic GVHD in two cases. Disease progression and death occurred in six patients. One patient had stable disease, one had hematologic improvement and three achieved complete responses. INTERPRETATION AND CONCLUSIONS: This study shows that the production of allogeneic CIK cells is feasible under clinical-grade conditions, well tolerated and may contribute to clinical responses.

Cytokine-induced killer cells are terminally differentiated activated CD8 cytotoxic T-EMRA lymphocytes.

OBJECTIVE: Cytokine-induced killer cells (CIK) are CD3(+)CD56(+) T cells with natural killer (NK)-like cytotoxic activity used for the immunotherapy of tumors. We aimed to fully characterize CIK cells and define their ontogeny. MATERIALS AND METHODS: CIK were generated in vitro by stimulation of peripheral blood mononuclear cells or T-cell subsets with interferon-gamma, anti-CD3 and interleukin-2. They were fully characterized in terms of phenotype, cytotoxic activity, and gene expression with respect to circulating CD3(+)CD56(+) cells, NK cells, and CD56(-) T cells present in CIK cultures. RESULTS: We demonstrate that CIK are terminally differentiated CD8 T cells that derive from proliferating CD3(+)CD56(-)CD8(+) T cells. They express polyclonal T-cell receptor Vbeta chains and have acquired CD56, NKG2D, and large granular lymphocyte morphology, but lack expression of most NK-specific activating (NKp30, NKp44, NKp46) and inhibitory (KIR2DL1, KIR2DL2, KIR3DL1, NKG2A, CD94) receptors, and can kill K562 targets. Circulating CD3(+)CD56(+) cells are also CD8(+)CD16(-), but are oligoclonal, poorly cytotoxic for K562, and express lower levels of CD56 and NKG2D. Gene profiling of CIK, CD56(-) T and NK cells present at the end of culture shows that differences are much more limited between CIK and CD56(-) T compared to CIK and NK cells. Most of the genes upregulated in CIK cells compared to CD56(-) T cells are part of the tumor necrosis factor gene network. CONCLUSIONS: The CIK phenotype, that is CD45RA(+), CCR7(-), CD62L-weakly positive, CD11a(+), CD27(+), CD28(-), macrophage inflammatory protein 1alpha(+), perforin(+), Fas ligand(+) coincides almost exactly with that described for the T RA(+) effector memory CD27 single positive subset of terminally differentiated human memory T cells.