Engineering hematopoietic grafts: Purified allogeneic hematopoietic stem cells plus expanded CD8+ NK-T cells in the treatment of lymphoma

Abstract

A major benefit of allogeneic hematopoietic cell transplantation (HCT) in the treatment of malignancies is the graft-versus-tumor (GVT) effect conferred by lymphocytes contained within the graft. However, lymphocytes can also induce the potentially lethal complication of graft-versus-host disease (GVHD). We have previously reported a method of generating large numbers of ex vivo activated and expanded T cells with antitumor activity after culture with interferon-y, cross-linking antibodies to CD3, and interleukin-2. Murine splenocytes expanded under these conditions are a heterogeneous population of which approximately 20% to 60% of cells express natural killer (NK)-cell markers (NK1.1 and DX5) and display major histocompatibility complex (MHC)-unrestricted antitumor activity. Here we demonstrate the in vivo antitumor activity of this population of expanded CD8+ NK-T cells when transplanted across MHC barriers into tumor-bearing hosts. In cotransfer studies with purified allogeneic hematopoietic stem cells, expanded CD8+ NK-T cells confer GVT activity with minimal to no GVHD. In vitro studies show that, although expanded NK-T cells lyse normal allogeneic bone marrow cells, they preferentially mediate cytolysis against tumor targets. These cells persist in the peripheral circulation of host animals for at least 3 weeks posttransfer. GVT activity is dependent on perforin, but not on Fas-ligand. We conclude that expanded CD8+ NK-T cells may serve as a valuable adjuvant population for allogeneic HCT because they mediate GVT effects with minimal GVHD.

The anti-tumour activity of allogeneic cytokine-induced killer cells in patients who relapse after allogeneic transplant for haematological malignancies

“…The lower incidence of GHVD of allogeneic CIK cells have been convincingly shown in mouse models, 28 and was postulated to be due to less trafficking of CIK cells to GVHD sites. 29 This was also consistent with an earlier report on activated donor lymphocytes expanded with CD3/CD28 coated beads, where GVHD was observed in 7 out of 18 patients.…”

Silencing Human NKG2D, DAP10, and DAP12 Reduces Cytotoxicity of Activated CD8+ T Cells and NK Cells

“…From previous studies we had characterized cytolysis by activated and expanded T cells as being MHC unrestricted and TCR independent, requiring cell-cell contact, and relying on an intact granule release pathway; more recently, we identified NKG2D as the critical activating intermediary (23,29,42,43). Our finding that killing by activated and expanded CD8 ϩ T cells is sensitive to DAP10 silencing by RNAi is predictable given the exquisite relationship between cytolysis and Ab-mediated NKG2D blockade that we had observed from previous studies.…”

“…These T cells have broad in vitro and in vivo biological activity against inoculated tumors after both syngeneic and allogeneic bone marrow transplantation in rodent models (29,30). Autologous infusion of cells of this type in patients has been associated with minimal toxicity, can reduce the risk of tumor recurrence in patients with hepatocellular carcinoma after surgical resection, and may induce partial remissions in patients with relapse of lymphoma after bone marrow transplantation (31,32).…”

Repeated infusions of donor-derived cytokine-induced killer cells in patients relapsing after allogeneic stem cell transplantation: a phase I study

“…[17][18][19][20][21][22] Furthermore, CIK cells have shown potent anti-tumor activity in vivo in several animal models, and protected SCID mice more effectively than lymphokine-activated killer (LAK) cells. [15][16][17]19,[23][24][25] Moreover, the same cells did not interfere with bone marrow engraftment in vivo and had little GVHD activity in several allogeneic models. 19,23 Two phase I studies have been performed so far, using single or repeated injections of autologous CIK cells in a total of 22 patients, including lymphoma and hepatocellular carcinoma patients.…”

“…[15][16][17]19,[23][24][25] Moreover, the same cells did not interfere with bone marrow engraftment in vivo and had little GVHD activity in several allogeneic models. 19,23 Two phase I studies have been performed so far, using single or repeated injections of autologous CIK cells in a total of 22 patients, including lymphoma and hepatocellular carcinoma patients. [26][27][28] The total number of cells inoculated ranged from 3×10 9 to 22×10 9 .…”