Activating and Propagating Polyclonal Gamma Delta T Cells with Broad Specificity for Malignancies

Abstract

Purpose To activate and propagate populations of γδT cells expressing polyclonal repertoire of γ and δ TCR chains for adoptive immunotherapy for cancer, which has yet to be achieved. Experimental Design Clinical-grade artificial antigen presenting cells (aAPC) derived from K562 tumor cells were used as irradiated feeders to activate and expand human γδT cells to clinical scale. These cells were tested for proliferation, TCR expression, memory phenotype, cytokine secretion, and tumor killing. Results γδT cell proliferation was dependent upon CD137L expression on aAPC and addition of exogenous IL-2 and IL-21. Propagated γδT cells were polyclonal as they expressed Vδ1, Vδ2, Vδ3, Vδ5, Vδ7, and Vδ8 with Vγ2, Vγ3, Vγ7, Vγ8, Vγ9, Vγ10, and Vγ11 TCR chains. Interferon-γ production by Vδ1, Vδ2, and Vδ1negVδ2neg subsets was inhibited by pan-TCRγδantibody when added to co-cultures of polyclonal γδT cells and tumor cell lines. Polyclonal γδT cells killed acute and chronic leukemia, colon, pancreatic, and ovarian cancer cell lines, but not healthy autologous or allogeneic normal B cells. Blocking antibodies demonstrated that polyclonal γδT cells mediated tumor cell lysis through combination of DNAM1, NKG2D, and TCRγδ. The adoptive transfer of activated and propagated γδT cells expressing polyclonal versus defined Vδ TCR chains imparted a hierarchy (polyclonal>Vδ1>Vδ1negVδ2neg>Vδ2) of survival of mice with ovarian cancer xenografts. Conclusions Polyclonal γδT cells can be activated and propagated with clinical-grade aAPC and demonstrate broad anti-tumor activities, which will facilitate the implementation of γδT cell cancer immunotherapies in humans.

Delta One T Cells for Immunotherapy of Chronic Lymphocytic Leukemia: Clinical-Grade Expansion/Differentiation and Preclinical Proof of Concept

“…Although several methods have been described in the past 5 years that can generate substantial numbers of tumor-targeting Vd2 neg T cells in vitro, key unresolved problems still excluded a clinical application of these cells: (i) the use of unsafe reagents and materials (such as plant lectins and plastic culture plates) in the manufacturing process; (ii) the high level of variation in the composition of the final cell products, especially between different donors; and/or (iii) the low antitumor activity of the final product (6,18,30,31). In a previous study, Deniger and colleagues developed tumor-derived artificial antigen presenting cells (aAPC) to propagate high numbers of gd T cells expressing a polyclonal repertoire of g and d TCR chains (32). However, as pointed out by the authors (33), the method could not resolve critical obstacles associated with clinical application of gd T cells.…”

“…Of note, this interesting study confirmed the greater antitumor efficacy of Vd1 þ cells over Vd2 þ gd T cells, which correlated with their expression of NCRs, suggesting that colon carcinoma could be an interesting target for DOT cells. Along the same line, Deniger and colleagues showed that, among gd T-cell subsets, Vd1 þ T cells were the most efficient at targeting ovarian cancer xenografts in vivo (32). We used an in vivo xenograft CLL model previously shown to reproduce several aspects of human disease (26,27).…”

Adoptive Immunotherapy of Epithelial Ovarian Cancer with Vγ9Vδ2 T Cells, Potentiated by Liposomal Alendronic Acid

“…Adoptive immunotherapy using haploidentical purified gd T cells has recently achieved impressive results in a small-scale clinical study in lymphodepleted patients with treatment-refractory hematologic malignancy (36). Furthermore, Cooper et al (37) have developed an efficient K562-based feeder system that expands polyclonal gd T cells with cytolytic activity against tumor cells and derived xenografts that are naturally sensitive to these cells. Although Vg9Vd2 T cells have modest intrinsic antitumor activity, a key advantage associated with the use of these cells is the potential to target and regulate their activity in a pharmacologically dependent manner, as demonstrated in this article.…”

Adoptive Cell Therapy for Sarcoma

“…Ex vivo activated γδ T cells kill OS cell lines in vitro through several mechanisms including granzyme/perforin and Fas/Fas–ligand interaction [93]. These studies highlight the potential antisarcoma activity of γδ T cells and provide rationale to evaluate γδ T cells in clinical studies in the future, which should be feasible due to the recent advances in ‘clinical grade’ ex vivo expansion of γδ T cells [94]. …”