Graft-versus-host disease can be separated from graft-versus-lymphoma effects by control of lymphocyte trafficking with FTY720 (original) (raw)

Prevention of acute graft-versus-host disease by blocking T-cell entry to secondary lymphoid organs

Blood, 2008

In acute graft-versus-host disease (aGVHD), donor T cells attack the recipient's gastrointestinal tract, liver, and skin. We hypothesized that blocking access to distinct lymphoid priming sites may alter the specific organ tropism and prevent aGVHD development. In support of this initial hypothesis, we found that different secondary lymphoid organs (SLOs) imprint distinct homing receptor phenotypes on evolving alloreactive effector T cells in vivo. Yet preventing T-cell entry to specific SLOs through blocking monoclonal antibodies, or SLO ablation, did not alter aGVHD pathophysiology. Moreover, transfer of alloreactive effector T cells into conditioned secondary recipients targeted the intestines and liver, irrespective of their initial priming site. Thus, we demonstrate redundancy of SLOs at different anatomical sites in aGVHD initiation. Only prevention of T-cell entry to all SLOs could completely abrogate the onset of aGVHD.

A crucial role for antigen-presenting cells and alloantigen expression in graft-versus-leukemia responses

Nature Medicine, 2005

Graft-versus-leukemia (GVL) response after allogeneic bone marrow transplantation (BMT) represents one of the most potent forms of immunotherapy against malignant diseases 1 . Antigen-presenting cells (APCs) are crucial for the induction of graft-versus-host disease (GVHD) 2-6 , the most serious complication of allogeneic BMT, but their role in GVL responses is unclear. Using a series of clinically relevant mouse GVL tumor models, we found that APCs and alloantigen expression on tumors are crucial for GVL. Moreover, APCs of host origin predominated in GVL responses although donor APCs contributed as the acuity of tumor burden decreased.

Leucyl-leucine methyl ester-treated haploidentical donor lymphocyte infusions can mediate graft-versus-leukemia activity with minimal graft-versus-host disease risk.

Fas ligand pathways in a murine model, we hypothesized that LLME might be useful for treatment of delayed DLIs for potential GVL activity with a decreased risk of GVHD induction. In regard to the clinical setting, the ex vivo use of LLME for this purpose would circumvent any toxicity issues for donor stem cells, because by that time patients would have already achieved successful engraftment. For our preclinical studies, we used the haploidentical C57BL/6 (B6) (H2 b ) → ( (B6 × DBA/2)F 1 (H2 b/d ) murine model with lethally irradiated hosts that had received transplants of T-cell-depleted bone marrow cells and were challenged with the MMD2-8 myeloid leukemia line (H2 d ) of DBA/2 origin. A DLI of LLME-treated donor splenocytes, from B6 mice presensitized to recipient alloantigens, was administered in varying doses 14 days post-marrow transplantation, and the potential for both GVHD and GVL activity was assessed. All mice that received any dose of LLME-treated DLI survived indefinitely, without evidence of cachexia nor B-cell hypoplasia, in contrast to the severe and lethal GVHD induced by mock-treated DLI. Histological analysis largely correlated with the symptomatic findings and revealed no GVHD-like lesions in the spleens of LLME-treated DLI recipients, although some mice displayed various degrees of hepatic mononuclear infiltration. Most notably, mice given LLME-treated DLI also experienced DLI dose-dependent increases in survival against the challenge with the MMD2-8 leukemia. LLME-treated splenocytes remained immunocompetent, as these cells could proliferate in response to mitogens and to restimulation with ovalbumin when used as a recall antigen. In conclusion, LLME-treated DLI possesses immune potential and, in particular, GVL activity without inducing clinically evident GVHD.

In vitro separation of host specific graft-versus-host and graft-versus-leukemia cytotoxic T cell activities

Bone Marrow Transplantation

The association of graft-versus-host disease (GVHD) with lower relapse rates following allogeneic bone marrow transplantation (BMT) in humans led us to analyse post HLA-identical BMT derived anti-host cytotoxic Τ cells (CTL) for their putative anti-Ieukemic activity. To establish whether graft-versus-host (GVH) and graftversus-leukemia (GVL) activities are separate, CTL lines were generated at different time points post-BMT from three patients suffering from acute GVHD. These CTL lines, which exhibited lysis of host normal lymphocytes and neoplastic cells, were analysed at the clonal level. Three functionally different types of clones were characterized: clones directed at host specific minor Histocompatibility (mH) antigens which are shared by patient's periphera! blood lymphocytes (PBL) and leukemic cells; clones recognizing only host PBL but not host leukemic cells; and putative GVL clones directed at patient's neoplastic cells only. These data could explain the long controversies on dissection of GVH and GVL activities. Our results demonstrate that GVH and GVL activities can be dissected, while nonseparable effector cells which exhibit both activities do exist as well.

Secondary Lymphoid Organs Contribute to, but Are Not Required for the Induction of Graft-versus-Host Responses following Allogeneic Bone Marrow Transplantation: A shifting Paradigm for T Cell Allo-activation

Biology of Blood and Marrow Transplantation, 2010

Graft-versus-host disease (GVHD) remains the major complication of allogeneic bone marrow transplantation (allo-BMT). GVHD fundamentally depends upon the activation of donor T cells by host antigenpresenting cells (APCs), but the precise location of these interactions remains uncertain. We examined the role of secondary lymphoid organs (SLO) in the induction of GVHD by using homozygous aly/aly mice that are deficient in lymph nodes (LNs) and Peyer's patches (PPs). Lethally irradiated, splenectomized, aly/ aly (LN/PP/Sp2/2) mice and sham-splenectomized, aly/1 (LN/PP/Sp1/1) mice received BMT from either syngeneic (aly/aly) or allogeneic, major histocompatibility complex (MHC) disparate donors. Surprisingly, although LN/PP/Sp2/2 allo-BMT recipients experience a survival advantage, they developed significant systemic and target organ GVHD that is comparable to LN/PP/Sp1/1 controls. Early after allo-BMT, the activation and proliferation of donor T cells was significantly greater in the BM cavity of LN/PP/Sp2/2 mice compared to LN/PP/Sp1/1 controls. Donor T cells in LN/PP/Sp2/2 mice demonstrated cytolytic activity in vitro, but Graft vs Leukemia (GVL) activity could be overcome by increasing the tumor burden. These data suggest that SLO contribute to, but are not required for, allogeneic T cell responses, and suggest that the BM may represent an alternative, albeit less efficient site for T cell activation following allo-BMT.

Graft-versus-host disease after allogeneic hematopoietic stem cell transplantation induces a CD8+ T cell-mediated graft-versus-tumor effect that is independent of the recognition of alloantigenic tumor targets

Blood, 2004

Cure of hematologic malignancies after allogeneic hematopoietic stem cell transplantation is partially attributable to immunocellular antitumor reactions termed graft-versus-tumor (GvT) effect. GvT effects are heterogeneous with respect to effector cell populations, target antigens, and their interrelation with graft-versus-host disease (GvHD). In the present study, allogeneic parent-into-F1 murine transplantation models (BALB/c or C57BL/6 → [C57BL/6 × BALB/c]F1) with different tumors derived from either parental strain were used to evaluate tumor-specific GvT effects. Compared with syngeneic F1-into-F1 controls, significant CD8+ T cell-mediated GvT effects occurred in both allogeneic transplantation models, even in the absence of histoincompatibilities between donor cells and host tumor. Identical genetic background of donor and tumor precluded allorecognition of tumor cells, indicating that tumor-associated antigens (TAAs) were targeted. With allowance made for selective major his...