Cord Blood–Derived and Peripheral Blood–Derived Cytokine-Induced Killer Cells Are Sensitive to Fas-Mediated Apoptosis

Clinical Trials with Combination of Cytokine-Induced Killer Cells and Dendritic Cells for Cancer Therapy

Adoptive cellular immunotherapy (ACI) is a promising treatment for a number of cancers. Cytokine-induced killer cells (CIKs) are considered to be major cytotoxic immunologic effector cells. Usually cancer cells are able to suppress antitumor responses by secreting immunosuppressive factors. CIKs have significant antitumor activity and are capable of eradicating tumors with few side effects. They are a very encouraging cell population used against hematological and solid tumors, with an inexpensive expansion protocol which could yield to superior clinical outcome in clinical trials employing adoptive cellular therapy combination. In the last decade, clinical protocols have been modified by enriching lymphocytes with CIK cells. They are a subpopulation of lymphocytes characterized by the expression of CD3+ and CD56+ wich are surface markers common to T lymphocytes and natural killer NK cells. CIK cells are mainly used in two diseases: in hematological patients who suffer relapse after allogeneic transplantation and in patients with hepatic carcinoma after surgical ablation to eliminate residual tumor cells. Dendritic cells DCs could play a pivotal role in enhancing the antitumor efficacy of CIKs.

Efficacy and safety of cord blood-derived dendritic cells plus cytokine-induced killer cells combined with chemotherapy in the treatment of patients with advanced gastric cancer: a randomized Phase II study

Background

Cellular immunotherapy has been widely used in the treatment of solid tumors. However, the clinical application of cord blood-derived dendritic cells and cytokine-induced killer cells (CB-DC-CIK) for the treatment of gastric cancer has not been frequently reported. In this study, the efficacy and safety of CB-DC-CIK for the treatment of gastric cancer were evaluated both in vitro and in vivo.

Methods

The phenotypes, cytokines, and cytotoxicity of CB-DC-CIK were detected in vitro. Patients with advanced gastric cancer were divided into the following two groups: the experimental group (CB-DC-CIK combined with chemotherapy) and the control group (chemotherapy alone). The curative effects and immune function were compared between the two groups.

Results

First, the results showed that combination therapy significantly increased the overall disease-free survival rate (P=0.0448) compared with chemotherapy alone. The overall survival rate (P=0.0646), overall response rate (P=0.410), and disease control rate (P=0.396) were improved in the experimental group, but these changes did not reach statistical significance. Second, the percentage of T-cell subsets (CD4⁺, CD3⁻CD56⁺, and CD3⁺CD56⁺) and the levels of IFN-γ, TNF-α, and IL-2, which reflect immune function, were significantly increased (P<0.05) after immunotherapy. Finally, no serious side effects appeared in patients with gastric cancer after the application of cellular immunotherapy based on CB-DC-CIK.

Conclusion

CB-DC-CIK combined with chemotherapy is effective and safe for the treatment of patients with advanced gastric cancer.

The cytotoxic action of the CD56+ fraction of cytokine-induced killer cells against a K562 cell line is mainly restricted to the natural killer cell subset

BACKGROUND

Cytokine-induced killer cells are polyclonal T cells generated ex vivo and comprise two main subsets: the CD56- fraction, possessing an alloreactive potential caused by T cells (CD3+CD56-), and the CD56+ fraction, characterised by a strong antitumour capacity induced by natural killer-like T cells (NK-like T, CD3+CD56+) and natural killer cells (NK, CD3-CD56+ bright).

MATERIALS AND METHODS

We investigated the cytotoxic action of selected CD56+ cell subpopulations against a human chronic myeloid leukaemia (K562) cell line.

RESULTS

After immunomagnetic selection of the CD56+ cell fraction, NK bright cells (CD3-CD56+ bright) and two subsets of NK-like T cells (CD3+CD56+), called NK-like T CD56 dim and NK-like T CD56 bright, could be identified. The cytotoxic effect against K562 cells was mainly exerted by the NK bright subpopulation and resulted to be inversely correlated with the percentage of NK-like T CD56 dim cells in the culture. The lytic action appeared to be independent of cell degranulation as suggested by the lack of change in the expression of CD107a.

DISCUSSION

We conclude that the cytotoxic action of CD56+ cells against a K562 cell line is mainly due to the NK cells.

Efficacy and safety of cord blood-derived cytokine-induced killer cells in treatment of patients with malignancies

BACKGROUND AIMS

Adoptive immunotherapy with the use of cytokine-induced killer (CIK) cells represents an effective therapeutic option for treating malignancies. The characteristics and function of cord blood-derived CIK (CB-CIK) cells have been evaluated both in vitro and in vivo. In this study, we assessed the efficacy and safety of administering CB-CIK cells to patients with cancer.

METHODS

In this retrospective clinical trial, 15 patients with cancer received CB-CIK therapy with different cycles from April 2012 to August 2014. CB-CIK cells demonstrated a high percentage of main functional fraction CD3(+)CD56(+) and efficient anti-tumor activity in vitro.

RESULTS

After the infusion of CB-CIK cells, the subsets of CD3(+)CD4(+) T lymphocytes and CD3(-)CD56(+) T cells in the peripheral blood were significantly increased compared with those before the therapy. Of 15 patients, one patient with hepatocellular cancer and one patient with esophageal cancer achieved complete responses, two patients with ovarian cancer obtained partial remissions, 10 patients had stable disease and one patient with hepatocellular cancer had progressive disease. Acute toxicities including fever, slight fever, dizziness and other neurologic toxicities were few and occurred in patients after infusion of CB-CIK cells.

CONCLUSIONS

These results demonstrated the feasibility and safety of treating malignancies with CB-CIK cells. The study provides a potential therapeutic approach for the patients with poor health or older patients who cannot tolerate repeated collection of blood.