Cord blood as a source of non-senescent lymphocytes for tumor immunotherapy

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.

Immunity Enhancement in Immunocompromised Gastrointestinal Cancer Patients with Allogeneic Umbilical Cord Blood Mononuclear Cell Transfusion

Objectives. In order to enhance the immunity of cancer patients to prevent relapse or to prolong survival time, umbilical cord blood mononuclear cells (UCMCs) were transplanted to cancer patients. Patients and Methods. UCMCs were transfused to 63 immunocompromised gastrointestinal cancer patients with nonmyeloablative (NMA) conditioning regimen. Results. The clinical study showed that the number of both T and B cells increased much more rapidly after transfusion of UCMCs than that of the control group without transplantation (p < 0.01). Proinflammation cytokines IFNγ and TNFα in serum increased to or above the normal range in 80.9% of patients at 12 weeks after UCMC transfusion. However, they recovered to the normal range in 21.7% of patients at the same time point in the control group only. In addition, the clinical investigation also showed that the transfusion of UCMC increased stable disease (SD) and reduced progressive disease (PD) significantly (p < 0.01); however, it did not have significant effects on complete response (CR), partial response (PR), or mortality rates compared with the control group (p > 0.05). Conclusions. UCMCs have powerful repairing effects on damaged cells and tissues and may reconstruct the impaired immunity. Transfusion of UCMCs could reconstruct the immunity of cancer patients with immunosuppression.

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.

Predicting cytotoxic T-cell age from multivariate analysis of static and dynamic biomarkers

Adoptive T-cell transfer therapy relies upon in vitro expansion of autologous cytotoxic T cells that are capable of tumor recognition. The success of this cell-based therapy depends on the specificity and responsiveness of the T cell clones before transfer. During ex vivo expansion, CD8+ T cells present signs of replicative senescence and loss of function. The transfer of nonresponsive senescent T cells is a major bottleneck for the success of adoptive T-cell transfer therapy. Quantitative methods for assessing cellular age and responsiveness will facilitate the development of appropriate cell expansion and selection protocols. Although several biomarkers of lymphocyte senescence have been identified, these proteins in isolation are not sufficient to determine the age-dependent responsiveness of T cells. We have developed a multivariate model capable of extracting combinations of markers that are the most informative to predict cellular age. To acquire signaling information with high temporal resolution, we designed a microfluidic chip enabling parallel lysis and fixation of stimulated cell samples on-chip. The acquisition of 25 static biomarkers and 48 dynamic signaling measurements at different days in culture, integrating single-cell and population based information, allowed the multivariate regression model to accurately predict CD8+ T-cell age. From surface marker expression and early phosphorylation events following T-cell receptor stimulation, the model successfully predicts days in culture and number of population doublings with R2=0.91 and 0.98, respectively. Furthermore, we found that impairment of early signaling events following T cell receptor stimulation because of long term culture allows prediction of costimulatory molecules CD28 and CD27 expression levels and the number of population divisions in culture from a limited subset of signaling proteins. The multivariate analysis highlights the information content of both averaged biomarker values and heterogeneity metrics for prediction of cellular age within a T cell population.