In vivo analyses of early events in acute graft-versus-host disease reveal sequential infiltration of T-cell subsets

Abstract

Graft-versus-host disease (GVHD) is a major obstacle in allogeneic hematopoietic cell transplantation. Given the dynamic changes in immune cell subsets and tissue organization, which occur in GVHD, localization and timing of critical immunological events in vivo may reveal basic pathogenic mechanisms. To this end, we transplanted luciferase-labeled allogeneic splenocytes and monitored tissue distribution by in vivo bioluminescence imaging. High-resolution analyses showed initial proliferation of donor CD4 ؉ T cells followed by CD8 ؉ T cells in secondary lymphoid organs with subsequent homing to the intestines, liver, and skin. Transplantation of purified naive T cells caused GVHD that was initiated in secondary lymphoid organs followed by target organ manifestation in gut, liver, and skin. IntroductionAllogeneic hematopoietic cell transplantation (HCT) has proven to be an effective therapy for a variety of life-threatening malignancies. 1 The beneficial effects of HCT are due to the graft-versustumor reaction, which is capable of destroying residual tumor cells that persist after chemotherapy or radiation therapy. 2 However, allogeneic HCT is limited by the immunologic recognition and destruction of host tissues, termed graft-versus-host disease (GVHD). Acute GVHD continues to be a major source of morbidity and mortality following HCT, which limits treatment of a broader spectrum of diseases, such as autoimmune diseases or organ transplant rejection. 3,4 Tissue-specific destruction of GVHD target organs, as gastrointestinal tract, liver, and skin, underlines the importance of migration capacities of alloreactive T lymphocytes. 5,6 In the current study we aimed to determine the time points of organ infiltration and focused on the role of different lymphoid organs in initiating acute GVHD. We used in vivo bioluminescence imaging (BLI) to analyze the migration pattern of whole splenocytes after transplantation into allogeneic recipients. BLI has already proven to be a sensitive and accurate means of characterizing engraftment patterns of hematopoietic stem cells, of monitoring tumor cell growth, and of assessing response to conventional and biological therapies. [7][8][9] We also aimed to clarify the role of different T-cell subsets during GVHD development. It is reported in the literature [10][11][12] that CD4 ϩ effector memory T (T EM ) cells do not cause GVHD. This prompted us to characterize their trafficking and proliferation pattern in vivo, while comparing it to purified naive CD4 ϩ T lymphocytes. Materials and methods MiceFVB/N (H-2 q , Thy1.1) mice and Balb/c mice (H-2 d , Thy1.2) were purchased from Jackson Laboratory (Bar Harbor, ME). The luciferaseexpressing (luc ϩ ) transgenic FVB/N line was generated as previously described. 9 Female heterozygous luc ϩ offspring of the transgenic founder line FVB-L2G85 were used for all transplantation experiments. All animal studies were performed under institutional approval. Flow cytometric cell purification and analysisThe following antibodies were purchased from...

Expression of α4β7 integrin on memory CD8+ T cells at the presentation of acute intestinal GVHD

“…11,12 Defining the specific adhesion molecules involved in this process of lymphocyte trafficking may provide novel opportunities for the monitoring, prophylaxis and treatment of acute GVHD after HCT.…”

Organ-derived dendritic cells have differential effects on alloreactive T cells

“…Three days after adoptive transfer of CFSE-labeled naive allogeneic T cells (B10.BR) into lethally irradiated hosts (C57BL/ 6), we found significant up-regulation of LPAM-1 on rapidly dividing alloreactive T cells in MLNs compared with PLNs ( Figure 1A,B). 37 The expression of E-lig and P-lig was up-regulated in PLNs but not in MLNs. We conclude that alloreactive T cells in MLNs up-regulate LPAM-1, whereas alloreactive T cells in PLNs express more E-lig and P-lig.…”

“…37,59 We chose our experimental approach to at least partially recapitulate this initial priming and imprinting phase circumventing the need for trafficking to secondary lymphoid organs. Despite an earlier report that Peyer patches are crucial for the initiation of a graft-versus-host reaction (GVHR), 60 there is evidence that this may not apply to GVHD and that secondary lymphoid organs may compensate for each other.…”

In vitro-established alloantigen-specific CD8+ CTLs mediate graft-versus-tumor activity in the absence of graft-versus-host disease

“…3 These T-cell subsets contribute differently to the pathogenesis of GVHD. CD4 þ T EM from non-alloantigen-primed donors fail to induce GVHD [4][5][6] because of an impaired cytotoxic immune response towards the alloantigen. 7 However, in vivo priming of CD4 þ T cells with recipient alloantigen induces alloantigenspecific CD4 þ T EM with GVHD-mediating capacities.…”

“…5,7,10 After transfer, naïve T cells immediately migrate to secondary lymphoid organs, followed by massive expansion and subsequent infiltration into GVHD target organs. 6,13 Allogeneic priming in the host enables transplanted naïve T cells not only to induce GVHD but also to mediate an efficient anti-tumor response. Despite their lack of GVHDinducing capacity, memory T cells can also eradicate tumor cells, indicating that GVHD induction and tumor elimination are not only dependent on antigen recognition of target cells but might additionally depend on microenvironment, cell numbers and proliferative capacities.…”