Human interferon-alpha increases the cytotoxic effect of CD56+cord blood-derived cytokine-induced killer cells on human B-acute lymphoblastic leukemia cell lines

Preemptive interferon-α treatment could protect against relapse and improve long-term survival of ALL patients after allo-HSCT

Relapse was the major cause of treatment failure in patients with acute lymphoblastic leukemia (ALL) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We aimed to identify the efficacy and safety of preemptive interferon-α (IFN-α) treatment in ALL patients who had minimal residual disease (MRD) after allo-HSCT. Multiparameter flow cytometry and polymerase chain reaction assays were applied for MRD monitoring. Recombinant human IFN-α-2b injections were administered subcutaneously twice weekly in every 4 weeks cycle. Twenty-four (35.3%), 5 (7.4%), 6 (8.8%), and 13 (19.1%) patients achieved MRD negativity at 1, 2, 3, and > 3 months, respectively, after treatment. Seven patients showed grade ≥ 3 toxicities after IFN-α treatment. The 4-year cumulative incidence of total acute graft-versus-host disease (aGVHD), severe aGVHD, total chronic GVHD (cGVHD), and severe cGVHD after treatment was 14.7%, 2.9%, 40.0%, and 7.5%, respectively. The 4-year cumulative incidences of relapse and non-relapse mortality after treatment was 31.9% and 6.0%, respectively. The 4-year probabilities of disease-free survival and overall survival after IFN-α treatment were 62.1% and 71.1%, respectively. Thus, preemptive IFN-α treatment could protect against relapse and improve long-term survival for ALL patients who had MRD after allo-HSCT. The study was registered at https://clinicaltrials.gov as #NCT02185261 (09/07/2014).

Umbilical cord blood: The promise and the uncertainty

Unfortunately, many patients referred for hematopoietic cell transplant will not have a fully matched related donor, and finding matched unrelated donors through the registry may be difficult, especially if the recipient is not of Northern European descent [N Engl J Med 2014;371:339‐348]. Umbilical cord blood (UCB) has been an available graft source for hematopoietic cell transplant for more than 30 years, since the first UCB transplant was performed in the late 1980s [N Engl J Med 1989;321:1174‐1178]. UCB is readily available, has low immunogenicity, and does not require as strict of human leukocyte antigen (HLA) matching compared to other graft sources [N Engl J Med 2004;351:2265‐2275]. According to data from the Center for International Blood and Marrow Transplant Research (CIBMTR), an estimated 500 patients in the US will have received a UCB transplant in 2018. Since 2014, haploidentical transplants have surpassed UCB transplants performed in the United States (CIBMTR Summary Slides, 2018, available at https://www.cibmtr.org). Increased use of haploidentical transplants has brought to light concerns about UCB transplants, including delayed engraftment and graft failure, increased nonrelapse mortality, increased infection risk, and UCB acquisition costs [Lancet Oncol 2010;11:653‐660; Biol Blood Marrow Transplant 2019;1456‐1464]. These concerns will need to be addressed for UCB to remain a viable option as a graft source for hematopoietic cell transplant. Other promising therapeutic benefits for UCB, in addition to hematopoietic cell transplant, is its use in regenerative medicine and immune modulation, which is currently being evaluated in ongoing clinical trials.

The biological macromolecule Nocardia rubra cell-wall skeleton as an avenue for cell-based immunotherapy

Promoting the antitumor effects of cell-based immunotherapy for clinical application remains a difficult challenge. Nocardia rubra cell-wall skeleton (N-CWS) is an immunotherapeutic agent for cancers that have been proven to possess the ability to activate immune response without showing toxicity. However, its effects on immune cells that are derived from tumor patients and cultured in vitro remain unclear. As expected, N-CWS can enhance the proliferation and viability of cytokine-induced killer (CIK) cells, dendritic cells (DCs), and natural killer (NK) cells. The maturation of DCs and specific cytotoxicity against NK cells and CIK cells were consistently promoted. The TUNEL-staining and the Annexin V/propidium iodide assay revealed that after treatment with N-CWS, the stimulated CIK/NK cells could induce DNA breaks in tumor cells. Furthermore, quantitative real-time polymerase chain reaction and western blot analysis showed upregulation of proapoptotic biomarkers (caspase-3 and caspase-9) and a downregulation of the antiapoptotic biomarker Bcl-2 in the tumor cells of the N-CWS-treated group, indicating that N-CWS could induce hepatocellular carcinoma cell apoptosis via CIK/NK cells. Finally, CIK/NK cells could notably suppress the invasion and migration of tumor cells in the presence of N-CWS. Our study provides evidence that N-CWS could significantly increase the growth of CIK cells, DCs, and NK cells, particularly due to its robust antitumor activities by inducing apoptosis, and attenuate the invasion and migration of tumor cells.

Cord blood-derived cytokine-induced killer cells combined with blinatumomab as a therapeutic strategy for CD19+ tumors

BACKGROUND

Cytokine-induced killer cells (CIKs) are an advanced therapeutic medicinal product (ATMP) that has shown therapeutic activity in clinical trials but needs optimization. We developed a novel strategy using CIKs from banked cryopreserved cord blood units (CBUs) combined with bispecific antibody (BsAb) blinatumomab to treat CD19⁺ malignancies.

METHODS

CB-CIKs were expanded in vitro and fully characterized in comparison with peripheral blood (PB)-derived CIKs.

RESULTS

CB-CIKs, like PB-CIKs, were mostly CD3⁺ T cells with mean 45% CD3⁺CD56⁺ and expressing mostly TCR(T cell receptor)αβ with a TH1 phenotype. CB-CIK cultures had, however, a larger proportion of CD4⁺ cells, mostly CD56^-, as well as a greater proportion of naïve CCR7⁺CD45RA⁺ and a lower percentage of effector memory cells, compared with PB-CIKs. CB-CIKs were very similar to PB-CIKs in their expression of a large panel of co-stimulatory and inhibitory/exhaustion markers, except for higher CD28 expression among CD8⁺ cells. Like PB-CIKs, CB-CIKs were highly cytotoxic in vitro against natural killer (NK) cell targets and efficiently lysed CD19⁺ tumor cells in the presence of blinatumomab, with 30-60% lysis of target cells at very low effector:target ratios. Finally, both CB-CIKs and PB-CIKs, combined with blinatumomab, showed significant therapeutic activity in an aggressive PDX Ph⁺ CD19⁺ acute lymphoblastic leukemia model in NOD-SCID mice, without sign of toxicity or graft-versus-host disease. The improved expansion protocol was finally validated in good manufacturing practice conditions, showing reproducible expansion of CIKs from cryopreserved cord blood units with a median of 28.8 × 10⁶ CIK/kg.

DISCUSSION

We conclude that CB-CIKs, combined with bispecific T-cell-engaging antibodies, offer a novel, effective treatment strategy for leukemia.

Autologous cytokine-induced killer cell immunotherapy may improve overall survival in advanced malignant melanoma patients

AIMS

Our study was conducted to explore the efficacy of autologous cytokine-induced killer (CIK) cells in patients with advanced malignant melanoma. Materials & Methods: Here we reviewed 113 stage IV malignant melanoma patients among which 68 patients received CIK cell immunotherapy alone, while 45 patients accepted CIK cell therapy combined with chemotherapy. Results: We found that the median survival time in CIK cell group was longer than the combined therapy group (21 vs 15 months, p = 0.07). In addition, serum hemoglobin level as well as monocyte proportion and lymphocyte count were associated with patients' survival time.

CONCLUSIONS

These indicated that CIK cell immunotherapy might extend survival time in advanced malignant melanoma patients. Furthermore, serum hemoglobin level, monocyte proportion and lymphocyte count could be prognostic indicators for melanoma.

Anticancer cellular immunotherapies derived from umbilical cord blood

INTRODUCTION

The lack of highly effective drugs in many malignancies has prompted scientific interest in the development of alternative treatment strategies. Cellular immunotherapy involving the adoptive transfer of immune cells that potently recognize and eliminate malignantly transformed cells has become a promising new tool in the anticancer armory. Studies suggest that the unique biological properties of umbilical cord blood (UCB) cells could precipitate enhanced anticancer activity; hence, UCB could be an optimal source for immunotherapy with the potential to provide products with 'off-the-shelf' availability.

AREAS COVERED

In this review, the authors summarize data on the transfer of naturally occurring or genetically modified UCB cells to treat cancer. The focus within is on the phenotypic and functional differences compared to other sources, the alloreactive and anticancer properties, and manufacturing of these products. Therapies utilizing cytokine-induced killer (CIK) cells, natural killer (NK) cells and chimeric antigen receptor (CAR) T-cells, are discussed.

EXPERT OPINION

The cellular immunotherapy field has become a growing, exciting area that has generated much enthusiasm. There is evidence that anticancer immunotherapy with UCB-derived products is feasible and safe; however, considering the limited number of clinical trials using UCB-derived products, further studies are warranted to facilitate translation into clinical practice.

A comparison between cytokine- and bead-stimulated polyclonal T cells: the superiority of each and their possible complementary role

Cytokine-induced killer (CIK) cells and T cells expanded by co-stimulation with beads presenting anti-CD3 and -CD28 antibodies are both polyclonal T cells under intensive laboratory and clinical studies, but there has not been any direct comparison between both. We compared the expansion, memory T cell subsets and cytotoxicity for T cells expanded in parallel by the two methods. Bead-stimulated T cells showed superior expansion as compared to CIK cells on D14 of culture. Bead-stimulated T cells consisted of a significantly higher CD4(+) subset and significantly lower CD8(+) subset as compared to CIK cells, as well as a higher proportion of less terminally differentiated T cells and a higher proportion of homing molecules. On the other hand, CIK cells exhibited significantly superior cytotoxicity against two myelomonocytic leukemia cell lines (THP-1 and U937) and two RCC cell lines (786.0 and CaKi-2). The cytotoxicity on D14 against THP-1 was 58.1 % for CIK cells and 8.3 % for bead-stimulated T cells at E:T of 10:1 (p < 0.01). Cytotoxicity correlated positively with the proportion of the CD8 subset in the culture and was independent of NKG2D recognition of susceptible targets. Polyclonal T cells expanded by different methods exhibit different characteristics which may define the specific role of each in different clinical scenario. We postulate that the more potent CIK cells may offer short term benefit while bead-stimulated T cells may offer a more sustained immune response.

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.

Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts

We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML.

Cytokine-induced killer cells: A novel immunotherapy strategy for leukemia

Cytokine-induced killer (CIK) cells are NK-like T cells derived from peripheral blood mononuclear cells that are co-stimulated and expanded using cytokines for 14–21 days in vitro. CIK cells are a heterogeneous subset of highly-efficient cytotoxic T effector cells that mediate major histocompatibility complex-unrestricted cytotoxicity against a broad array of tumor cells. These effector cells are generated from patients with leukemia or healthy donors who demonstrate similar cytotoxic activity against leukemia blasts. Allogeneic CIK cells retain the ability to produce the graft versus tumor response and generate minimal graft versus host disease. In addition, CIK cells possess no cytotoxicity against normal hematopoietic stem cells in vivo. Leukemia recurrence remains a formidable obstacle, but adoptive immunotherapy offers promise for the eradication of minimal residual disease and prevention of leukemia relapse following hematopoietic stem cell transplantation. CIK cell infusion started a novel generation of adoptive immunotherapy and exhibits particular potential applications in the area of hematological malignancy. In the present study, the previous strategies of leukemia immunotherapy using CIK cells are reviewed and the future directions of development are discussed.

Phenotypic characterization and anti-tumor effects of cytokine-induced killer cells derived from cord blood

BACKGROUND AIMS

Cytokine-induced killer (CIK) cell therapy represents a feasible immunotherapeutic option for treating malignancies. However, the number of anti-tumor lymphocytes cannot be easily obtained from the cancer patients with poor immunity status, and older patients cannot tolerate repeated collection of blood. Cord blood-derived CIK (CB-CIK) cells have shown efficacy in treating the patients with cancer in several clinical trials. This study was conducted to evaluate the biological characteristics and anti-tumor function of CB-CIK cells.

METHODS

The immunogenicity, chemokine receptors and proliferation of CB-CIK cells were analyzed by flow cytometry. The CIK cells on day 13 were treated with cisplatin and the anti-apoptosis capacity was analyzed. The function of CB-CIK cells against the human cancer was evaluated both in vitro and in vivo.

RESULTS

Compared with peripheral blood-derived CIK (PB-CIK) cells, CB-CIK cells demonstrated lower immunogenicity and increased proliferation rates. CB-CIK cells also had a higher percentage of main functional fraction CD3(+)CD56(+). The anti-apoptosis ability of CB-CIK cells after treatment with cisplatin was higher than that of PB-CIK cells. Furthermore, CB-CIK cells were effective for secreting interleukin-2 and interferon-γ and a higher percentage of chemokine receptors CCR6 and CCR7. In addition, tumor growth was greatly inhibited by CB-CIK treatment in a nude mouse xenograft model.

CONCLUSIONS

CB-CIK cells exhibit more efficient anti-tumor activity in in vitro analysis and in the preclinical model and may serve as a potential therapeutic approach for the treatment of cancer.

Phenotypic and functional characterization of cytokine-induced killer cells derived from preterm and term infant cord blood

Cord blood has gradually become an important source for hematopoietic stem cell transplantation (HSCT) in the human, particularly in pediatric patients. Adoptive cellular immunotherapy of patients with hematologic malignancies after umbilical cord blood transplant is crucial. Cytokine‑induced killer (CIK) cells derived from cord blood are a new type of antitumor immune effector cells in tumor prevention and treatment and have increasingly attracted the attention of researchers. On the other hand, it has been suggested that preterm infant cord blood retains an early differentiation phenotype suitable for immunotherapy. Therefore, we determined the phenotypic and functional characterization of CIK cells derived from preterm infant cord blood (PCB-CIK) compared with CIK cells from term infant cord blood (TCB-CIK). Twenty cord blood samples were collected and classified into two groups based on gestational age. Cord blood mononuclear cells (CBMCs) were isolated, cultured and induced to CIK cells in vitro. We used flow cytometry to detect cell surface markers, FlowJo software to analyze the proliferation profile and intracellular staining to test the secretion of cytokines. Finally, we evaluated the antitumor activity of CIK cells against K562 in vitro. Compared with TCB-CIK, PCB-CIK cells demonstrated faster proliferation and higher expression of activated cell surface markers. The secretion of IL-10 was lower in PCB-CIK cells while the expression of perforin and CD107a had no significant difference between the two cell groups. PCB-CIK cells exhibited a high proliferation rate while the cytotoxic activity had no difference between the PCB-CIK and TCB-CIK cells. Hence preterm infant cord blood may be a potential source for immunotherapy.

Implication of different effector mechanisms by cord blood-derived and peripheral blood-derived cytokine-induced killer cells to kill precursor B acute lymphoblastic leukemia cell lines

BACKGROUND AIMS

Cytokine-induced killer (CIK) cells ex vivo-expanded from cord blood (CB) or peripheral blood (PB) have been shown to be cytotoxic against autologous and allogeneic tumor cells. We have previously shown that CD56(+) CIK cells (CD3(+)CD56(+) and CD3(-)CD56(+)) are capable of killing precursor B-cell acute lymphoblastic leukemia (B-ALL) cell lines. However, the lytic pathways used by CD56(+) PB and CB-CIK cells to kill B-ALL cell lines have not been studied.

METHODS

CB and PB-CIK cells were differentiated. CD56(+) CB- and PB-CIK cells were compared for expression of different phenotypic markers and for the lytic pathways used to kill B-ALL cell lines.

RESULTS

We found that cytotoxic granule proteins were expressed at higher levels in CD56(+) PB-CIK than in CD56(+) CB-CIK cells. However, CD56(+) CB-CIK cells expressed more tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) compared with CD56(+) PB-CIK cells. We observed that CD56(+) CB-CIK cells used both the NKG2D and TRAIL cytotoxic pathways and were more effective at killing REH cells than CD56(+) PB-CIK cells that used only the NKG2D pathway. In contrast, CD56(+) PB-CIK cells used both NKG2D and TRAIL pathways to kill NALM6 cells, whereas CD56(+) CB-CIK cells used only the NKG2D pathway.

CONCLUSIONS

Our results suggest that both the source of CIK and the type of B-ALL cell line have an impact on the intensity of the cytolytic activity and on the pathway used. These findings may have clinical implications with respect to optimizing therapeutic efficacy, which may be dependent on the source of the CIK cells and on the target tumor cells.