Cytokine-induced killer (CIK) cells as feasible and effective adoptive immunotherapy for the treatment of solid tumors

Abstract

Introduction: Cytokine-induced killer (CIK) cells are heterogeneous ex vivo-expanded T lymphocytes with mixed T-NK phenotype and endowed with a wide MHC-unrestricted antitumor activity. CIK cells can be expanded from peripheral blood mononuclear cells (PBMC) cultured with the timed addition of IFN-γ, Ab anti-CD3 and IL2. A consistent subset of mature CIK cells presents a CD3⁺CD56⁺ phenotype. The CD3⁺CD56⁺ cellular subset is the main responsible for the tumor-killing activity, mostly mediated by the interaction of NKG2D receptor with MHC-unrestricted ligands (MIC A/B; ULBPs) on tumor cells.

Areas covered: In the present work, we described the biologic characteristics of CIK cells, focusing on those aspects that may favor their clinical translation. We reviewed preclinical data and analyzed reports from clinical trials. A specific paragraph is dedicated to future research perspectives in the field.

Expert opinion: CIK cells represent a realistic new option in the field of cancer immunotherapy. Crucial issues, favoring their clinical translation, are the easy availability of large amounts of expanded CIK cells and their MHC-unrestricted tumor killing, potentially effective against many tumor types. Intriguing future perspectives and open challenges are the investigation of synergisms with other immunotherapy approaches, targeted therapies or even conventional chemotherapy.

Keywords::

• adoptive cell therapy
• CIK cells
• immunotherapy
• solid tumors

Acknowledgements

This work was supported in part by grants from Associazione Italiana per la Ricerca sul Cancro (AIRC) (grant 2011/2014), Associazione Italiana contro le Leucemie-linfomi e mieloma (AIL) and Associazione Donatrici Italiane Sangue Cordone Ombelicale (ADISCO, ONLUS). Grant Rete Oncologica Piemonte e Valle D'Aosta 2010. D Sangiolo is supported in part by ‘Assegno di Ricerca' funded by Regione Piemonte; V Leuci is supported in part by fellowship funded by Associazione Piemontese contro le Leucemie (APL). G Mesiano is supported in part by a fellowship funded by Associazione Donatrici Italiane Sangue Cordone Ombelicale.

Notes

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