Gene-Modified Human α/β-T Cells Expressing a Chimeric CD16-CD3ζ Receptor as Adoptively Transferable Effector Cells for Anticancer Monoclonal Antibody Therapy

Abstract

The central tumoricidal activity of anticancer monoclonal antibodies (mAb) is exerted by FcgR IIIa (CD16)-expressing effector cells in vivo via antibody-dependent cell-mediated cytotoxicity (ADCC), as observed for natural killer (NK) cells. In practice, chemotherapy-induced leukopenia and exhaustion of NK cells resulting from ADCC often hamper the clinical efficacy of cancer treatment. To circumvent this drawback, we examined in vivo the feasibility of T cells, gene-modified to express a newly generated affinity-matured (158V/V) chimeric CD16-CD3z receptor (cCD16z-T cells), as a transferable alternative effector for cancer mAb therapy. cCD16z-T cells were readily expandable in ex vivo culture using anti-CD2/CD3/CD28 beads and recombinant human interleukin-2 (rhIL-2), and they successfully displayed ADCC-mediated tumoricidal activity in vitro. During ADCC, ligation of opsonized cancer cells to the introduced cCD16z-T cells stimulated the effector cells to produce proinflammatory cytokines and release toxic granules through the activation of the Nuclear factor of activated T cells (NFAT) pathway after phosphorylation of the CD3z chain. In parallel, these stimulated cCD16z-T cells transiently proliferated and differentiated into effector memory T cells. In contrast, NK cells activated by rhIL-2 displayed similar ADCC activity, but failed to proliferate. Human cCD16z-T cells infused concomitantly with anti-CD20 mAb synergistically inhibited the growth of disseminated Raji cells, a CD20þ lymphoma cell line, in immunodeficient mice, whereas similarly infused rhIL-2-treated NK cells survived for a shorter time and displayed less effective tumor suppression. Our findings strongly suggest the clinical feasibility of cCD16z-T cells as adoptively transferable ADCC effector cells that could potentially enhance the clinical responses mediated by currently available anticancer mAbs.

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

“…In our previous study, as adoptively transferable ADCC effector cells, NK cells seemed less advantageous, mainly because they did not proliferate after execution of ADCC activity, leading to their shorter survival after infusion and limited efficacy both in vitro and in vivo (23). On the other hand, cCD16z-T cells proliferated transiently for about a week following execution of ADCC, resulting in longer survival in vivo and greater tumor suppression (23). (Fig.…”

“…S1A) was synthesized and inserted into the lentiviral vector, pRRLSIN. cPPT.MSCV/GFP.WPRE (26), as described elsewhere (23).…”

“…cCD16z gene-transduced T cells (cCD16z-T cells) were established as described elsewhere (23 (25) and subsequently subjected to functional assays.…”

“…In addition, accumulated evidence has confirmed the long-term safety of retro-or lentivirally gene-modified T cells for adoptive cell therapy in terms of the risk of leukemogenesis (21,22). In this context, we have previously examined whether lentivirally gene-modified CD3 þ T cells can express a newly designed FcgRIIIa-158(V/V)-CD3z chimeric receptor (cCD16z-T cell) as an alternative ADCC effector (23).…”

FCγ Chimeric Receptor-Engineered T Cells: Methodology, Advantages, Limitations, and Clinical Relevance

“…With a similar purpose, later Ochi and collaborators (36) proposed a variant of the CD16-CR obtained by linking the CD16 with the TM and the intracellular portion of CD3ζ (CD16ζ). The chimeric receptor was successfully expressed by lentiviral transduction on T cell surface of a healthy donor, and ADCC activity was reported against CD20 + lymphoma, Her2/neu + breast cancer and T-cell leukemia cell lines coated with rituximab, trastuzumab, and mogamulizumab (Mog), respectively.…”