Development of Engineered T Cells Expressing a Chimeric CD16-CD3ζ Receptor to Improve the Clinical Efficacy of Mogamulizumab Therapy Against Adult T-Cell Leukemia

Abstract

Purpose: Mogamulizumab (Mog), a humanized anti-CC chemokine receptor 4 (CCR4) mAb that mediates antibody-dependent cellular cytotoxicity (ADCC) using FcγR IIIa (CD16)-expressing effector cells, has recently been approved for treatment of CCR4-positive adult T-cell leukemia (ATL) in Japan. However, Mog failure has sometimes been observed in patients who have accompanying chemotherapy-associated lymphocytopenia. In this study, we examined whether adoptive transfer of artificial ADCC effector cells combined with Mog would overcome this drawback. Experimental Design: We lentivirally gene-modified peripheral blood T cells from healthy volunteers and ATL patients expressing the affinity-increased chimeric CD16-CD3ζ receptor (cCD16ζ-T cells). Subsequently, we examined the ADCC effect mediated by those cCD16ζ-T cells in the presence of Mog against ATL tumor cells both in vitro and in vivo. Results: cCD16ζ-T cells derived from healthy donors killed in vitro Mog-opsonized ATL cell line cells (n = 7) and primary ATL cells (n = 4) depending on both the number of effector cells and the dose of the antibody. cCD16ζ-T cells generated from ATL patients (n = 3) also exerted cytocidal activity in vitro against Mog-opsonized autologous ATL cells. Using both intravenously disseminated model (n = 5) and subcutaneously inoculated model (n = 4), coadministration of Mog and human cCD16ζ-T cells successfully suppressed tumor growth in xenografted immunodeficient mice, and significantly prolonged their survival (P < 0.01 and P = 0.02, respectively). Conclusions: These data strongly suggest clinical feasibility of the novel combined adoptive immunotherapy using cCD16ζ-T cells and Mog for treatment of aggressive ATL, particularly in patients who are ineligible for allogeneic hematopoietic stem cell transplantation. Clin Cancer Res; 22(17); 4405–16. ©2016 AACR.

Extended half-life target module for sustainable UniCAR T-cell treatment of STn-expressing cancers

“…Previous studies using conventional CARs have reported attenuated activation signaling due to the formation of longer immunological synapses and variations in the antigen location and density on target cells [31,32]. Interestingly, recent reports highlight the effective formation of the immunological synapse and consequent T cell activation using different modular CAR formats, demonstrating a surprising plasticity and variability of such approaches [3,33,34]. Here, we demonstrate that the immunological synapse formed by the large αSTn-IgG4 TMs does not affect the activation nor cytotoxic potential of UniCAR T-cells targeting the STn antigen.…”

Fc γ receptor compositional heterogeneity: Considerations for immunotherapy development

“…Antibodies have been the focus of many engineering efforts likely due to the rapidly deployable and highly generalizable nature of mAbs with relatively little attention paid to FcgRs themselves (55). Though FcgRs provide useful modules for chimeric protein design, these designs generally do not enhance FcgR functionality and, with one exception, will not be discussed here (a few examples include (56)(57)(58)(59)). These early FcgR engineering reports provide a strong justification for further engineering to increase affinity and increase the activity of engineered leukocytes.…”

CARs: Beyond T Cells and T Cell-Derived Signaling Domains

“…Fcγ CRs have been pre-clinically tested by different groups [213][214][215][216][217][218][219]. Summarizing these studies, CD16A or a high-affinity variant (V158) was either coupled directly or via a CD8α linker and TM domain to a signaling tail, consisting of CD3ζ, 4-1BB/CD3ζ, or FcεRIγ (Figure 1).…”

“…These constructs have been retrovirally transduced or transfected [214,215] into human T cells, murine MD45 T cells, human peripheral blood NK cells, or NK-92 cells. These cells have been employed in combination with a variety of mAbs (anti-CD19, anti-CD20 (Rituximab), anti-HER2 (Trastuzumab), anti-GD2, anti-Panc1, anti-EGFR (Cetuximab, Panitumumab), or anti-CSPG4) against different cancer cells (Daudi, Raji, and adult T cell lymphoma, neuroblastoma, osteosarcoma, pancreatic cancer, colorectal cancer, and A375 melanoma cells) in vitro, as well as against lymphoma-xenografted mice [213][214][215][216][217][218][219]. Fcγ CR cells showed promising anti-tumor activity in all these studies [213][214][215][216][217][218][219], and via the attached signaling domains, activated the NF-AT pathway [213].…”